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1.
We measured the self-diffusion coefficients of water in a Nafion membrane and two sulfonated polyethersulfone (SPES) membranes
with varying ion-exchange capacities (IEC) in terms of relative humidity using the pulse field gradient NMR (PFG-NMR) technique.
The self-diffusion coefficients were plotted against the number of water molecules per sulfonic acid group, λ, and compare these values with the results of molecular dynamics (MD) simulations. Classical MD simulations for all membranes
were carried out using a consistent force field at λ = 3, 6, 9, 12, and 15. The dynamic properties of water (H2O) and hydronium (H3O+) on a molecular level were estimated as self-diffusion coefficients and residence times around a sulfonate group (
\textSO3- {\text{SO}}_3^{-} ). The diffusion coefficients of H2O and H3O+ followed the order, Nafion > SPES with IEC = 1.4 > SPES with IEC = 1.0 > SPES with IEC = 0.75, which agreed with the experimental
data. The residence time distribution of H2O around
\textSO3- {\text{SO}}_3^{-} in Nafion was in the range of 1–6 ps, whereas H2O in the SPES exhibited a residence time of greater than 20 ps. 相似文献
2.
Nonenzymatic glycation of long-lived proteins has been implicated in several complications related to age and diabetes. Dicarbonyl
compounds such as methylglyoxal (MGO) have been identified as the predominant source for the formation of advanced glycation
end-products (AGEs) in various tissues. We investigated the effect of 13 micronutrients on MGO-mediated in vitro glycation
of bovine serum albumin (BSA), as formation of AGEs and protein carbonyls. BSA (10 mg/ml) was incubated at 37°C with 100 mM
MGO for 24 hours, in presence of ascorbic acid, Trolox (water-soluble α-tocopherol analog), β-carotene, retinol, riboflavin,
thiamin, folic acid, niacin, pyridoxine, zinc, iron, manganese, and selenium. Fluorescence was measured at the wavelength
pair of 370 and 440 nm as an index of the formation of AGEs and spectra were recorded for promising interactions at λex = 280 nm and λex = 370 nm. Within four standard antiglycating agents, aminoguanidine showed highest inhibitory response for BSA glycation
followed by quercetin, gallic acid, and tannic acid. Promising antiglycation potential was seen for Trolox, riboflavin, Zn,
and Mn as evidenced by decrease in the formation of AGEs and protein carbonyls. 相似文献
3.
Timo Vihma 《International journal of biometeorology》2010,54(3):297-306
The effects of air temperature, relative and specific humidity, wind speed, solar shortwave radiation, thermal longwave radiation,
and rain on the performance of participants in the annual Stockholm Marathon from 1980 to 2008 were analysed statistically.
The objective was to validate and extend previous studies by including data on finishing times of slower male and female runners
and on the percentage of non-finishers. Due to decadal trends in the finishing time not related to weather, the finishing
time anomaly (FTA) was calculated as the deviation of the annual finishing time from the linear trend of the finishing time.
In all categories of runners, the single weather parameter with highest correlation with the FTA was the air temperature (correlation
coefficient r = 0.66–0.73, with the highest values for slowest runners). Also, the solar shortwave radiation (r = 0.41–0.71), air relative humidity (r = −0.57 to −0.44) and, for male runners, the occurrence of rain (r = −0.51 to −0.42) reached a statistically significant correlation with the FTA, but the effects of the relative humidity
and rain only arose from their negative correlation with the air temperature. The percentage of non-finishers (PNF) was significantly
affected by the air temperature and specific humidity (r = 0.72 for multiple regression), which is a new result. Compared to faster runners, the results of slower runners were more
affected by unfavourable weather conditions; this was previously known for runners with finishing times of 2.1–3 h, and now
extended to finishing times of 4.7 h. Effects of warm weather were less evident for female than male runners, which was probably
partly due to female runners’ larger ratio of surface area to body mass and slower running speed. 相似文献
4.
Warangkana Prakoon Suriyan Tunkijjanukij Thuy T. T. Nguyen Uthairat Na-Nakorn 《Marine biotechnology (New York, N.Y.)》2010,12(5):506-515
The culture of green mussel (Perna viridis) in the Gulf of Thailand depends on natural spat which are believed to come from spawning grounds adjacent to major river
mouths. In the present paper, genetic diversity of spatial and temporal populations of green mussel in the Gulf of Thailand
was investigated using five microsatellite loci. The results showed moderate genetic variation of all 11 populations (averaged
number of alleles per locus, A = 10.4–12.2; effective number of alleles per locus, A
e = 5.36–6.59; mean allelic richness, A
r = 10.23–12.06; observed heterozygosity, H
o = 0.52–0.63, and expected heterozygosity, H
e = 0.66–0.73) without significant differences among populations. No sign of bottleneck or genetic disequilibrium was observed.
Genetic differentiation among spatial populations was low (F
ST = 0.0046, CI0.95 = 0.0020–0.0083 for the samples collected in January, 2007, and F
ST = 0.0088, CI0.95 = 0.0010–0.0162 for the samples collected in July, 2007) while temporal variation was significant as revealed by the analysis
of molecular variance. Multidimensional scaling separated temporal population groups with minor exception. The assignment
test revealed that most of the recruits were from other populations. 相似文献
5.
Amaia Larruskain Esmeralda Minguijón Koldo García-Etxebarria Bernardino Moreno Inmaculada Arostegui Ramón A. Juste Begoña M. Jugo 《Immunogenetics》2010,62(2):75-83
Ovine pulmonary adenocarcinoma (OPA) and Maedi–Visna (Maedi) are two chronic respiratory diseases of retroviral origin which
occur worldwide. It is known that different host genetic factors influence the outcome of viral infections. To determine if
variation in the Mhc-DRB1 gene was associated with progression to these ovine diseases, sheep lungs with and without OPA and Maedi lesions were collected.
A sequence-based method was applied and 40 different alleles were detected in the sample analysed. In the allele-by-allele
association analysis, allele DRB1*0325 had a significant association with susceptibility to Maedi (P = 0.045). For OPA, DRB1*0143 and DRB1*0323 were significantly associated with susceptibility (P = 0.024 and P = 0.029), and allele DRB1*0702 was significantly associated with resistance (P = 0.012). Based on these results, the Mhc-DRB1 alleles were classified by effect in three categories—susceptible (S), resistant (R) and neutral (N)—and animals were reassigned
the genotypes as S/S, S/R, S/N, R/R, R/N and N/N. In a second analysis, penalised logistic regression models including a flock
effect were run. In Maedi, significant association was detected for the N/S heterozygote (P = 0.0007), but not for the S/S homozygote, probably as a result of the low number of S/S animals. In OPA, association was
detected for both the S/S and R/R homozygotes (P = 0.005 and P = 0.047). This allele grouping method may be applied in association studies with highly variable genes. This is the first
study demonstrating significant associations between sheep Mhc-DRB1 alleles and susceptibility to OPA and Maedi. Therefore, both diseases are suitable candidates for more comprehensive genetic
studies. 相似文献
6.
Kandhro GA Kazi TG Afridi HI Kazi N Arain MB Sarfraz RA Sirajuddin Syed N Baig JA Shah AQ 《Biological trace element research》2008,125(3):203-212
In many developing countries, women are at high risk of goiter and iron deficiency anemia (IDA). Iron deficiency adversely
affects thyroid metabolism and may decrease the efficiency of thyroid hormones in areas of endemic goiter. The aim of the
present study was to compare the level of iron (Fe) in biological samples (serum and urine) and serum thyroid hormones, thyroid
stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) of goitrous female patients (GFPs; n = 69) with those of nongoitrous women as control subjects (n = 117), age range 21–45 years. The biological samples were analyzed for Fe concentration using flame atomic absorption spectrophotometer,
prior to microwave-assisted wet acid digestion. The validity and accuracy of the method was checked by the certified sample
and with those obtained by conventional wet acid digestion method on the same CRM and real samples. The overall recoveries
of Fe in serum and urine were found in the range of 97.2–98.6% of certified values. The results of this study showed that
the mean values of Fe in serum and urine samples of GFPs were significantly reduced as compared to control subjects (p = 0.002 and p = 0.015, respectively). The mean values of FT3 and FT4 were found to be lower in GFPs than in the age-matched healthy control
women; in contrast, high mean values of TSH were detected in GFPs (p = 0.003). There was a positive correlation between serum Fe concentration and TSH (r = 0.85, p = 0.01), FT3 (r = 0.95, p = 0.003), and FT4 levels (r = 0.98, p = 0.007) in GFPs. It was observed that iron deficiency is prevalent in GFPs, so the need of Fe supplementation will be required
to improve the efficacy of thyroid metabolism in goitrous women. 相似文献
7.
J. B. Gaughan T. L. Mader S. M. Holt M. L. Sullivan G. L. Hahn 《International journal of biometeorology》2010,54(6):617-627
Cattle production plays a significant role in terms of world food production. Nearly 82% of the world’s 1.2 billion cattle
can be found in developing countries. An increasing demand for meat in developing countries has seen an increase in intensification
of animal industries, and a move to cross-bred animals. Heat tolerance is considered to be one of the most important adaptive
aspects for cattle, and the lack of thermally-tolerant breeds is a major constraint on cattle production in many countries.
There is a need to not only identify heat tolerant breeds, but also heat tolerant animals within a non-tolerant breed. Identification
of heat tolerant animals is not easy under field conditions. In this study, panting score (0 to 4.5 scale where 0 = no stress
and 4.5 = extreme stress) and the heat load index (HLI) [HLIBG<25°C = 10.66 + 0.28 × rh + 1.30 × BG – WS; and, HLI BG> 25°C = 8.62 + 0.38 × rh + 1.55 × BG – 0.5 × WS + e(2.4 – WS), where BG = black globe temperature (oC), rh = relative humidity (decimal form), WS = wind speed (m/s) and e is the base of the natural logarithm] were used to
assess the heat tolerance of 17 genotypes (12,757 steers) within 13 Australian feedlots over three summers. The cattle were
assessed under natural climatic conditions in which HLI ranged from thermonuetral (HLI < 70) to extreme (HLI > 96; black globe
temperature = 40.2°C, relative humidity = 64%, wind speed = 1.58 m/s). When HLI > 96 a greater number (P < 0.001) of pure bred Bos taurus and crosses of Bos taurus cattle had a panting score ≥ 2 compared to Brahman cattle, and Brahman-cross cattle. The heat tolerance of the assessed breeds
was verified using panting scores and the HLI. Heat tolerance of cattle can be assessed under field conditions by using panting
score and HLI. 相似文献
8.
The carbon-flux via algal bloom events involves bacteria as an important mediator. The present study, carried out during the
spring inter-monsoon month of April 2008 onboard CRV Sagar Manjusha-06 in the Eastern Arabian Sea, addresses the bloom-specific
flow of carbon to bacteria via chromophoric dissolved organic matter (CDOM). Eleven stations monitored were located in the
coastal, shelf and open-ocean areas off Ratnagiri (16°59′N, 73°17′E), Goa (15°30′N, 73°48′E) and Bhatkal (13°58′N, 74°33′E)
coasts. Visible bloom of “saw-dust” color in the Ratnagiri shelf were microscopically examined and the presence of cyanobacteria
Trichodesmium erythraeum and T. thieabautii with cell concentrations as high as 3.05 × 106 trichomes L−1 was recorded. Total bacterial counts (TBC) varied between 94.09 × 108 cells L−1 in the bloom to 1.34 × 108 cells L−1 in the non-bloom area. Chromophoric dissolved organic matter (CDOM) concentrations averaged 2.27 ± 3.02 m−1 (absorption coefficient 325 nm) in the bloom to 0.28 ± 0.07 m−1 in the non-bloom waters respectively. CDOM composition varied from a higher molecular size with lower aromaticity in the
bloom to lower molecular size and increased aromaticity in the non-bloom areas respectively. Strong positive relationship
of TBC with Chlorophyll a (R
2 = 0.65, p < 0.01) and CDOM concentrations (R
2 = 0.8373, p = 0.01) in the bloom area indicated hydrolysis and/or uptake of CDOM by bacteria. Absorption by mycosporine-like amino acid
palythene (λ
max = 360 nm) was recorded in the filtrate of bloom. Morphotypes of Trichodesmium-associated bacteria revealed a higher frequency of Gram-positive rods. The role of bacteria in relation to changing CDOM
nature and as a factor in affecting oxygen content of the water column is discussed in context of the Arabian Sea. 相似文献
9.
Two responses to elicitins are described in cultivars of radish (Raphanus sativus L.). Type I, exhibited by the cultivar Daikon, is characterised by wilting and desiccation within 24 h of elicitin application
and was previously reported as the sensitive response (S. Kamoun et al. 1993, Mol Plant-Microbe Interact 6: 15–25). At 1 μg
elicitin · g−1 FW radish tissue, symptoms appeared after 8 h, a sensitivity comparable to that shown by tobacco to β elicitins (J.-C. Pernollet
et al., 1993, Physiol Mol Plant Pathol 42: 53–67; S. Kamoun et al., 1993, Mol Plant-Microbe Interact 6: 15–25). Elicitin failed
to induce these symptoms in the cultivar White Icicle, even at 100 μg · g−1 FW of tissue. However, a different response (Type II) with symptoms resembling senescence appeared in White Icicle after
48 h and were fully developed by 72 h. The Type II response was induced at levels of elicitin above 0.3 μg · g−1 FW. Elicitin-treated Daikon leaves held at 100% relative humidity, rather than ambient (50–60%) did not wilt and by 72 h
displayed Type II symptoms. When treated Daikon leaves were removed to ambient humidity at any time during the latent period,
they developed Type I symptoms within 2 h. Although Type I symptoms were suppressed in Daikon at high humidity, there was
no indication that leaf diffusion resistance or plant water conductance were affected. Protoplasts from the cultivar Daikon
responded to elicitin by H+ uptake and K+ release, with maximal response at 300 pM. The response was eliminated by K252a or staurosporine. Daikon protoplasts also
showed transient uptake/secretion of Ca2+ on elicitin addition. Protoplasts from White Icicle gave neither of these responses. Both Daikon and White Icicle phenotypes
could be transferred to progeny of Daikon-White Icicle crosses and in the F2 generation three phenotypes, including a null,
segregated. Only those F2 plants which exhibited the Daikon phenotype produced protoplasts which responded to elicitin.
Received: 13 May 1997 / Accepted: 27 August 1997 相似文献
10.
Esma Ucisik-Akkaya Charronne F. Davis Clara Gorodezky Carmen Alaez M. Tevfik Dorak 《Cell stress & chaperones》2010,15(5):475-485
Three heat shock protein 70 (HSP70) genes, HSPA1L, HSPA1A, and HSPA1B, are located within the human leukocyte antigen (HLA) class III region. HSPs act as stress signals and regulate natural killer
cell response to cancer. HSP70 gene polymorphisms show disease associations partly due to their linkage disequilibrium with HLA alleles. To systematically evaluate their associations with childhood acute lymphoblastic leukemia (ALL), we examined the
three functional single nucleotide polymorphisms (SNPs) rs2227956 (T493M) in HSPA1L, rs1043618 in HSPA1A 5′UTR, and rs1061581 (Q351Q) in HSPA1B by TaqMan assays or polymerase chain reaction–restriction fragment length polymorphism in 114 ALL cases and 414 controls
from Wales (UK), in 100 Mexican Mestizo ALL cases and 253 controls belonging to the same ethnic group, and in a panel of 82
HLA-typed reference cell line samples. Homozygosity for HSPA1B rs1061581 minor allele G was associated with protection (odds ratio (OR) = 0.37, 95% confidence interval (CI) = 0.16–0.78;
P = 0.007) with gene-dosage effect (additive model) reaching significance (P = 0.0001) in the Welsh case–control group. This association was replicated in the second case–control group from Mexico (OR
(recessive model) = 0.49, 95% CI = 0.24–0.96; P = 0.03), and the pooled analysis yielded a strong association (Mantel–Haenszel OR = 0.43, 95% CI = 0.27–0.69, P = 0.0004). The association was stronger in males in each group and in the pooled analysis. A three-SNP haplotype including
the major allele A of rs1061581 showed a highly significant increase in Welsh cases compared with respective controls (6.7%
vs 1.8%; P = 0.0003) due to the difference between male cases and controls. The protective allele of rs1061581 occurred more frequently
on the HLA-DRB3 haplotypes (especially DRB1*03) in the cell line panel, but the HSPA1B association was independent from the HLA-DRB4 association previously detected in the same case–control group from Wales (adjusted P = 0.001). Given the cancer promoting roles played by HSPs intracellularly as well as roles in immune surveillance when expressed
on the cell surface and the known correlations between expression levels and the HSP polymorphisms, these results are likely to indicate a primary association and warrant detailed assessment in childhood ALL
development. 相似文献
11.
The microsolvation of taurine (TA) with one, two or three water molecules was investigated by a density functional theory
(DFT) approach. Quantum theory of atoms in molecules (QTAIM) analyses were employed to elucidate the hydrogen bond (H-bond)
interaction characteristics in TA-(H2O)n (n = 1–3) complexes. The results showed that the intramolecular H-bond formed between the hydroxyl and the N atom of TA are
retained in most TA-(H2O)n (n = 1–3) complexes, and are strengthened via cooperative effects among multiple H-bonds from n = 1–3. A trend of proton transformation exists from the hydroxyl to the N atom, which finally results in the cleavage of
the origin intramolecular H-bond and the formation of a new intramolecular H-bond between the amino and the O atom of TA.
Therefore, the most stable TA-(H2O)3 complex becomes a zwitterionic complex rather than a neutral type. A many-body interaction analysis showed that the major
contributors to the binding energies for complexes are the two-body energies, while three-body energies and relaxation energies
make significant contributions to the binding energies for some complexes, whereas the four-body energies are too small to
be significant. 相似文献
12.
N. J. Adams B. Pinshow L. Z. Gannes H. Biebach 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1999,169(3):195-199
We examined the relationship between body temperature (Tb) of free flying pigeons and ambient water vapor pressure and temperature. Core or near core Tb of pigeons were measured using thermistors inserted into the cloaca and connected to small transmitters mounted on the tail
feathers of free flying tippler pigeons (Columba livia). Wet and dry bulb temperatures were measured using modified transmitters mounted onto free-flying pigeons. These allowed
calculation of relative humidity and hence water vapor pressure at flight altitudes. Mean Tb during flight was 42.0 ± 1.3 °C (n = 16). Paired comparisons of a subset of this data indicated that average in-flight Tb increased significantly by 1.2 ± 0.7 °C (n = 7) over that of birds at rest (t = −4.22, P < 0.05, n = 7) within the first 15 min of takeoff. In addition, there was a small but significant increase in Tb with increasing ambient air (Ta) when individuals on replicate flights (n = 35) were considered. Inclusion of water vapor pressure into the regression model did not improve the correlation between
body temperature and ambient conditions. Flight Tb also increased a small (0.5 °C) but significant amount (t = 2.827, P < 0.05, n = 8) from the beginning to the end of a flight. The small response of Tb to changing flight conditions presumably reflects the efficiency of convection as a heat loss mechanism during sustained
regular flight. The increase in Tb on landing that occurred in some birds was a probable consequence of a sudden reduction in convective heat loss.
Accepted: 2 February 1999 相似文献
13.
Toshihiro Yokoo Kouki Kanou Masato Moteki Hiroshi Kohno Prasert Tongnunui Hisashi Kurokura 《Ichthyological Research》2006,53(4):330-336
Juveniles of three eleotrid Butis species (B. butis, B. humeralis, and B. koilomatodon) are described; their occurrence patterns were examined in Sikao Creek, a mangrove estuary located in southern Thailand.
Juveniles of each species were distinguished by the following characters: B. butis with no bands on body and pale pelvic fins; B. humeralis with no bands on body and densely pigmented pelvic fins; and B. koilomatodon with 5–6 regular bands on body and a fleshy process (preorbital knob) on the snout. Although B. butis shared the aforementioned characters with B. amboinensis found in the same estuary, the former was distinguished from the latter by having a greater number of pectoral fin rays (18–21
vs. 17) and a deeper caudal peduncle. Distribution patterns of the three Butis species in Sikao Creek were distinguishable from each other. Smaller B. butis [mean ± SD = 22.7 ± 16.9 mm in standard length (SL), n = 32] occurred in the upper reach of the estuary, while larger specimens (52.4 ± 26.2 mm SL, n = 18 and 51.5 ± 29.7 mm SL, n = 10, respectively) were found in the middle and lower reaches and none in the marine area. In B. humeralis and B. koilomatodon, only juveniles were caught except for one adult specimen each. Juveniles (8.9–16.5 mm SL, n = 79) of B. humeralis occurred in the upper and middle reaches and the marine area. B. koilomatodon juveniles (9.9–13.7 mm SL, n = 30) were distributed in all areas from the lower to upper reaches. 相似文献
14.
Mohamed A. Haidara Mohamed D. Morsy Hesham A. Abdel-Razek Dimitri P. Mikhailidis Esma R. Isenovic 《Journal of physiology and biochemistry》2010,66(3):255-264
Septicemia leads to oxidative stress with overproduction of reactive-oxygen species (ROS) and consumption of endogenous antioxidant
enzymes. We tested a twofold hypothesis: (1) does oxidative stress (OxS) induced by sepsis acting alone or in concert with
augmented inflammatory processes contributes to sepsis-related vascular dysfunction, and, (2) whether ozone (O3) and l-canavanine (CAV) mitigate the negative impact of the aforementioned phenomena. We investigated the relative impact of treatment
with CAV and/or O3 on vascular OxS associated vascular functional changes in septicemic rats. For this study, 60 male Sprague–Dawley rats were
used and divided into six experimental groups (n = 10): control group (C), sham-operated (Sham), septicemic rats (S), S rats treated with CAV (100 mg/kg. i.p; S + CAV), S
rats treated with O3 (1.2 mg/kg, i.p.; S + O3) and S rats treated with both O3 and CAV (S + O3 + CAV). After 22 h, the mean arterial blood pressure (MAP), the aortic ring vascular reactivity to phenylephrine, abdominal
aortic blood flow (AABF), serum tumor necrosis factor-α (TNF-α) and plasma nitrite/nitrate (NOx) concentration were measured.
In addition, hepatic antioxidant enzyme activities sodium dismutase (SOD) and glutathione peroxidase (GSH-Px) were estimated.
Septicemia caused significant elevation of serum TNF-α (p < 0.001) and plasma NOx (p < 0.001) and significant (p < 0.001) reduction of AABF (p < 0.001), aortic vascular response to phenylephrine (p < 0.001), MAP (p < 0.001) and hepatic SOD and GSH-Px activity (p < 0.001) compared with the C group, while treatment with O3 and/or CAV induced significant amelioration of all those increases. Abnormalities were attenuated to a similar extent with
treatment with both O3 and CAV. These results suggested that concomitant administration of O3 and CAV alleviated the compromised vascular reactivity in septicemic conditions and prevent its progression into septic shock
compared with each alone. 相似文献
15.
This work mainly studies the effects of the position (there are two possible hydrated sites) and the manner (i.e., whether
water acts as a proton donor or acceptor) of hydration by various numbers of water molecules on the stability of 14 solvated
N-methylacetamide structures, NMA-(H2O)
n
(n = 1–3), as well as the binding strength between the NMA and the water cluster, using molecular dynamics (MD) and B3LYP methods.
Natural bond orbital (NBO) analysis is used to explore the origin of these effects. Some novel observations are obtained from
the work. Our results show that monohydration at the carbonyl site favors stability and binding strength compared to monohydration
at the amino site. Similarly, the preferred hydration at the carbonyl site is observed for dihydrated NMAs when the second
water is added as a proton donor to the C=O group or the first water is H-bonded to the C=O group. However, unfavorable hydration
at the C=O site occurs if the second water acts as a proton acceptor. Trihydration by a ring cluster of three water molecules
at either the carbonyl site or the amino one yields relatively stable complexes, but significantly disfavors binding strength.
The other trihydrated NMAs show similar behavior to dihydrated NMAs. In addition, our results show that the C=O and N–H frequencies
can still be utilized to examine the H-bond effects of the water cluster. 相似文献
16.
Data on zinc concentration in the human body may be used to interpret the results obtained in cases of chronic and acute poisonings
with zinc compounds, i.e., in clinical and forensic toxicology. In this paper, the concentrations of zinc in human tissues
and body fluids obtained from autopsy cases concerning non-poisoned people (n = 203), aged from 14 to 80 years, between 1995 and 2008, are presented. The following values were found by the flame atomic
absorption method (mean ± SD, median, range, in microgram per gram or microgram per milliliter): brain 10.3 ± 1.36, 10.2,
7.99–13.8 (n = 48); stomach 14.2 ± 3.63, 13.6, 8.00–22.5 (n = 71); intestines 15.7 ± 5.22, 15.8, 8.36–28.1 (n = 35); liver 39.6 ± 16.1, 36.6, 16.0–78.8 (n = 109); kidney 33.8 ± 10.1, 31.8, 16.4–60.9 (n = 93); lung 12.0 ± 3.88, 11.0, 6.13–18.7 (n = 26); spleen 14.7 ± 2.53, 14.6, 11.4–18.3 (n = 5); heart 26.5 ± 3.63, 26.7, 22.5–31.8 (n = 5); blood 6.81 ± 1.21, 7.00, 4.02–8.68 (n = 50); urine 0.69 ± 1.70, 0.60, 0.39–1.00 (n = 5), and bile 4.92 ± 1.64, 3.75, 3.20–7.09 (n = 9). The accuracy of the method was checked through the use of SRM Bovine Liver 1577b (certified: 127 ± 16 μg Zn/g, found:
117 ± 0.7 μg Zn/g (n = 6)). 相似文献
17.
The aim of the study was to determine the relationship of fluoride in drinking water to liver function in individuals living
in normal and seven endemic fluorosis areas of Punjab, India. The concentration of fluoride in drinking water of different
areas varied from 5.9 to 24.5 mg/L. Study group consisted of 705 patients in the age group between 20 and 60 years (mean age
of 39.35 ± 11.27) affected with osteodental fluorosis were compared with 300 age- and sex-matched controls (with mean age
of 35.28 ± 8.25 years). Biochemical data was analyzed by one-way analysis of variance (ANOVA) with post hoc Tukey–Kramer and
Bonferroni multiple comparison tests. The relationship between hepatic enzymes was calculated by Pearson’s correlation and
linear regression. The results revealed significantly (P < 0.001) higher concentration of serum fluoride in patients when compared to control. The mean activities of cyclic adenosine
monophosphate (AMP), alkaline phosphatase (ALKP), acid phosphatase (ACP), aspartate aminotransaminase (AST), and alanine aminotransaminase
(ALT) were significantly (P < 0.05–0.001) elevated in patients from all fluoride areas. ANOVA with post hoc Turkey–Kramer and Bonferroni multiple comparison
test demonstrated a significant (P < 0.0001) variance in the activities of cAMP, ALKP, ACP, AST, and ALT in fluorotic patients, with elevation in water fluoride
levels. Maximum elevation of 196.14% (ACP), 99.31% (cyclic adenosine monophosphate; cAMP), 72.08% (ALT), 60.14% (AST), and
least 21.35% (ALKP) was recorded in patients exposed to 24.5 mg/L fluoride in drinking water. There was positive correlation
between water fluoride, serum fluoride and AST (r = 0.77, 0.91), ALT (r = 0.82, 0.90), ALKP (r = 0.88, 0.97), and ACP (r = 0.74, 0.85). Pearson’s correlation demonstrated highly significant (P < 0.05) positive relationship between water fluoride and cAMP (regression equation: Y = 0.9807 ×+ 22.081 Y = 0.9807 \times + 22.081 , = 0.84; r = 0.92, P < 0.05). The increased levels of transaminases in fluorotic patients suggest alteration in liver functions. The level of
alkaline and acid phosphatase was increased during fluoride intoxication which is also an early marker of hepatic cell damage
because of its specificity and catalytic activity. The elevated levels of enzymes are reflective of bone disorders, which
are characterized by increased osteoblastic activity. There levels increased several times if cellular damage occurs in the
liver. The results suggest that fluoride exposure intensifies the activities of hepatic function enzymes in osteofluorosis. 相似文献
18.
A new species Dolichopteryx minuscula is described on the basis of three specimens [49.4–59.6 mm in standard length (SL)] collected from the Indo-West Pacific.
The new species is characterized by pouchlike eyes with a small lens (lens diameter 2.2% SL), an adipose fin, the anal fin
base originating posterior to the dorsal fin base, and 16–17 (= 5–6 + 1 + 10–11) gill rakers. Total fecundity was relatively
low, only 658 ova being obtained from one specimen, despite the ovary being mature. Ovarian eggs were clearly subdivided into
“undeveloped” (0.1–0.7 mm diameter classes, n = 561) and “developed” (1.0–1.3 mm classes, n = 97) groups, based on their frequency distribution. Such relatively low fecundity and frequency distributions of ovarian
eggs suggest that Dolichopteryx species spawn iteratively during spawning season. 相似文献
19.
Solovchenko A Khozin-Goldberg I Recht L Boussiba S 《Marine biotechnology (New York, N.Y.)》2011,13(3):527-535
In order to develop a practical approach for fast and non-destructive assay of total fatty acid (TFA) and pigments in the
biomass of the marine microalga Nannochloropsis sp. changes in TFA, chlorophyll, and carotenoid contents were monitored in parallel with the cell suspension absorbance.
The experiments were conducted with the cultures grown under normal (complete nutrient f/2 medium at 75 μmol PAR photons/(m2 s)) or stressful (nitrogen-lacking media at 350 μmol PAR photons/(m2 s)) conditions. The reliable measurement of the cell suspension absorbance using a spectrophotometer without integrating
sphere was achieved by deposition of cells on glass–fiber filters in the chlorophyll content range of 3–13 mg/L. Under stressful
conditions, a 30–50% decline in biomass and chlorophyll, retention of carotenoids and a build-up of TFA (15–45 % of dry weight)
were recorded. Spectral regions sensitive to widely ranging changes in carotenoid-to-chlorophyll ratio and correlated changes
of TFA content were revealed. Employing the tight inter-correlation of stress-induced changes in lipid metabolism and rearrangement
of the pigment apparatus, the spectral indices were constructed for non-destructive assessment of carotenoid-to-chlorophyll
ratio (range 0.3–0.6; root mean square error (RMSE) = 0.03; r
2 = 0.93) as well as TFA content of Nannochloropsis sp. biomass (range 5.0–45%; RMSE = 3.23 %; r
2 = 0.89) in the broad band 400–550 nm normalized to that in chlorophyll absorption band (centered at 678 nm). The findings
are discussed in the context of real-time monitoring of the TFA accumulation by Nannochloropsis cultures under stressful conditions. 相似文献
20.
Cedrus libani of Lebanon is a valuable natural resource and the dominant species in its natural ecosystem. Intense and diverse anthropogenic
pressures over historical times raised concerns about its genetic vigor and continued survival. Our investigation of the genetic
diversity included samples from all remnant natural populations. Assessment of the genetic diversity using random amplified
polymorphic DNA markers revealed the persistence of considerable variation distributed within populations with low population
differentiation corroborated by Bayesian and analysis of molecular variance estimates (G
ST = 0.07, Φ
ST = 0.09). Individual assignment tests were carried out to investigate measures of gene flow. Inferences concluded that this
natural heritage is not currently threatened by inbreeding or by random genetic drift. Correlation studies investigated possible
effects of spatial distribution and environmental conditions on genetic structure. A climatic trend corresponding to a temperature–humidity
gradient correlated significantly with the level of genetic diversity, while the edaphic variation did not. 相似文献