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1.
T. Rütting H. Brandt W. Clauβ V. Dzapo D. Selzer 《European Journal of Wildlife Research》2007,53(3):171-177
The aim of the study was to determine differences in the behaviour of chicks of three different pheasant subspecies. The timidity
of the pheasant chicks was of special interest, therefore behaviour traits were analysed using an open-field test and a tonic
immobility test. In total, 137 pheasant chicks were tested including the copper pheasant (Ph. c. colchicus; n = 87), the green pheasant (Ph. c. versicolor; n = 12) and the melanistic pheasant (Ph. c. tenebrosus; n = 38). In both tests, the chicks of the versicolor group showed the highest timidity, whereas the other two groups were similar
in timidity. In the open-field test, the chicks of the colchicus group showed the lowest timidity, and in the tonic immobility
test, the tenebrosus group showed the lowest values. Assuming a relationship between the test results and predator avoidance
behaviour, it can be concluded that the chicks of the versicolor group show the best predator avoidance behaviour. Further
investigations are needed to find out whether the differences in the analysed behaviour traits result in higher survival rates
after releasing to the wild. 相似文献
2.
A new species of the genus Paracobitis, Paracobitis nanpanjiangensis is described from tributaries of the Nanpanjiang River drainage in China. It is distinguished from its congeners, except
P. oligolepis and P. wujiangensis, by body scaleless or with rudimentary scales (caudal peduncle with several deeply embedded scales). It can be differentiated
from P. wujiangensis by the complete lateral line (vs. incomplete), lower dorsal crest reaching the vertical of origin of anal fin (vs. shorter
and higher dorsal crest not reaching the base of anal fin). It is distinguished from P. oligolepis by the following characters: branched dorsal fin with 81/2 (a few 91/2) rays (vs. 91/2), interspaces between bars in front
of dorsal fin conspicuously thinner than those behind (vs. vermiform markings), dorsal head without vermiform markings or
obscure (vs. clearly vermiform markings on dorsal head), vertebrae 4 + 36–38 (vs. 4 + 39–41). 相似文献
3.
Kimotsuki T Niwa N Hicks MN Dunne M Cobbe SM Watanabe MA 《Journal of biological physics》2010,36(3):299-315
Roughly speaking, restitution is the dependence of recovery time of cardiac electrical activity on heart rate. Increased restitution
slope is theorized to be predictive of sudden death after heart injury such as from coronary artery occlusion (ischemia).
Adrenaline analogs are known to increase restitution slope in normal hearts, but their effects in failing hearts are unknown.
Twenty-six rabbits underwent coronary ligation (n = 15) or sham surgery (n = 11) and implantation of a lead in the heart for recording electrocardiograms. Eight weeks later, unanesthetized rabbits
were given 0.25–2.0 ml of 1 μmol/L isoprenaline intravenously, which increased heart rate. Heart rate was quantified by time
between QRS peaks (RR) and heart activity duration by R to T peak time (QTp). Ligated rabbits (n = 6) had lower ejection fraction than sham rabbits (n = 7, p < 0.0001) indicative of heart failure, but similar baseline RR (269 ± 15 vs 292 ± 23 ms, p = 0.07), QTp (104 ± 17 vs 91 ± 9 ms, p = 0.1), and isoprenaline-induced minimum RR (204 ± 11 vs 208 ± 6 ms, p = 0.4). The trajectory of QTp vs TQ plots displayed hysteresis and regions of negative slope. The slope of the positive slope
region was >1 in ligated rabbits (1.27 ± 0.66) and <1 in sham rabbits (0.35 ± 0.14, p = 0.004). The absolute value of the negative slope was greater in ligated rabbits (− 0.81 ± 0.52 vs − 0.35 ± 0.14, p = 0.04). Isoprenaline increased heart rate and slopes of restitution trajectory in failing hearts. The dynamics of restitution
trajectory may hold clues for sudden death in heart failure patients. 相似文献
4.
Data on the concentration of the elements in the human body are important, for example, to estimate the amounts required to
maintain a good healthy state or find their connections with morbidity and mortality. In this paper, the concentration of
copper (by flame atomic absorption spectrometry) in material obtained from autopsy cases of nonpoisoned people (n = 130), aged from 14 to 80 years, between 1990–2006, is presented. The following values were found (mean ± SD in micrograms
of copper per gram or per milliliter): brain 3.32 ± 1.50 (n = 43), liver 3.47 ± 1.51 (n = 79), kidney 2.15 ± 0.90 (n = 76), stomach 1.10 ± 0.76 (n = 65), intestines 1.54 ± 1.19 (n = 25), lung 1.91 ± 1.30 (n = 27), spleen 1.23 ± 0.28 (n = 3), heart 3.26 ± 0.59 (n = 5), bile 3.60 ± 1.67 (n = 13), and blood 0.85 ± 0.19 (n = 73). 相似文献
5.
Public acceptance of evolution in Northeastern U.S. is the highest nationwide, only 59%. Here, we compare perspectives about
evolution, creationism, intelligent design (ID), and religiosity between highly educated New England faculty (n = 244; 90% Ph.D. holders in 40 disciplines at 35 colleges/universities) and college students from public secular (n = 161), private secular (n = 298), and religious (n = 185) institutions: 94/3% of the faculty vs. 64/14% of the students admitted to accepting evolution openly and/or privately,
and 82/18% of the faculty vs. 58/42% of the students thought that evolution is definitely true or probably true, respectively.
Only 3% of the faculty vs. 23% of the students thought that evolution and creationism are in harmony. Although 92% of faculty
and students thought that evolution relies on common ancestry, one in every four faculty and one in every three students did
not know that humans are apes; 15% of the faculty vs. 34% of the students believed, incorrectly, that the origin of the human
mind cannot be explained by evolution, and 30% of the faculty vs. 72% of the students was Lamarckian (believed in inheritance
of acquired traits). Notably, 91% of the faculty was very concerned (64%) or somehow concerned (27%) about the controversy
evolution vs creationism vs ID and its implications for science education: 96% of the faculty vs. 72% of the students supported
the exclusive teaching of evolution while 4% of the faculty vs. 28% of the students favored equal time to evolution, creationism
and ID; 92% of the faculty vs. 52% of the students perceived ID as not scientific and proposed to counter evolution or as
doctrine consistent with creationism. Although ≈30% of both faculty and students considered religion to be very important
in their lives, and ≈20% admitted to praying daily, the faculty was less religious (Religiosity Index faculty = 0.5 and students = 0.75) and, as expected, more knowledgeable about science (Science Index faculty = 2.27 and students = 1.60) and evolution (Evolution Index faculty = 2.48 and students = 1.65) than the students. Because attitudes toward evolution correlate (1) positively with understanding
of science/evolution and (2) negatively with religiosity/political ideology, we conclude that science education combined with
vigorous public debate should suffice to increase acceptance of naturalistic rationalism and decrease the negative impact
of creationism and ID on society’s evolution literacy. 相似文献
6.
Nina Dehnhard Maud Poisbleau Laurent Demongin Katrin Ludynia Petra Quillfeldt 《Ibis》2014,156(3):548-560
Juvenile survival is an important demographic parameter. Southern Rockhopper Penguins Eudyptes chrysocome have undergone a dramatic population decline in the past century across their distribution, but the demographic processes are poorly understood. To estimate juvenile annual survival probabilities, Rockhopper Penguin chicks from two cohorts on New Island, Falkland Islands, were marked with transponders and recorded in subsequent years using an automated gateway. We first estimated annual survival and detection probabilities using a Cormack‐Jolly‐Seber (CJS) model, and found that both probabilities were extremely high (81% in the first and 98% in the second, third and fourth years of life), even in comparison with adult birds. Because detection probability after 3 years was effectively 1, and our sample size (n = 114) was too small to explore the effects of individual traits on survival in a CJS model, we assessed whether sex, cohort, body mass and laying sequence affected whether juveniles returned to the colony during their first 3 years of life using a simple generalized linear model that assumed perfect detection. Juveniles from the first cohort and males showed a higher return probability than juveniles from the second cohort and females. There was no clear effect of fledging body mass on return rate, probably related to the favourable environmental conditions during the study period. The laying sequence did not markedly affect the return probability of chicks, indicating that, once fledged, first‐laid A‐chicks have the same probability to return as second‐laid B‐chicks despite a much larger initial maternal investment in B‐eggs in this species. This study demonstrates extraordinarily high juvenile survival probabilities and will help to understand the recent changes in the population dynamics of the Falkland Islands Southern Rockhopper Penguins. 相似文献
7.
Atle Wibe Anna-Karin Borg-Karlson Torbjörn Norin Hanna Mustaparta 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,180(6):585-595
Naturally produced plant volatiles, eliciting responses of single olfactory receptor neurons in the pine weevil, have been
identified by gas chromatography linked with mass spectrometry. The receptor neurons (n = 72) were classified in 30 types, according to the compound which elicited the strongest response in each neuron, 20 of
which compounds were identified. Most potent for 14 types of neurons (n = 50) were monoterpenes, including bicyclic (e.g. α-pinene, camphor and myrtenal) for 8 types (n = 32), monocyclic (limonene, carvone, α-terpinene) for 3 types (n = 12) and acyclic (e.g. β-myrcene and linalool) for 3 types (n = 6). Other compounds eliciting strongest responses of a neuron were five sesquiterpenes, including α-copaene and a farnesene-isomer,
and an anethole type which has no biosynthetic relationship with terpenes. Within one type, receptor neurons with quite selective
responses to the most potent compound as well as neurons with additional responses to several, structurally similar compounds
were found, indicating that the neurons may have the same functional types of membrane receptors, but different sensitivities.
Response spectra of neurons within the bicyclic-, mono-cyclic and acyclic types showed more overlapping than across the neuron
types. Minimal overlapping response spectra was found between monoterpene and sesquiterpene neurons. The results suggest that
this structure-activity relationship is significant for encoding plant odour information in the pipe weevil.
Accepted: 6 January 1997 相似文献
8.
Kerstin Müller Rainer Altenkamp Jens Raila Daniel Schmidt Robert Dietrich Andrea Hurtienne Michael Wink Oliver Krone Leo Brunnberg Florian J. Schweigert 《European Journal of Wildlife Research》2011,57(5):1043-1049
In this study, we investigated the α-tocopherol plasma concentrations in healthy free-ranging nestlings of the white-tailed
sea eagle (Haliaeetus albicilla) (n = 32), osprey (Pandion haliaetus) (n = 39), northern goshawk (Accipiter gentilis) (n = 25), common buzzard (Buteo buteo) (n = 31), and honey buzzard (Pernis apivorus) (n = 18) as well as of free-ranging adults of the white-tailed sea eagle (n = 10), osprey (n = 31), and northern goshawk (n = 45). α-Tocopherol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. α-Tocopherol
plasma concentrations in nestlings of osprey, white-tailed sea eagle, and northern goshawk did not differ significantly amongst
the species, but the common buzzard and honey buzzard nestlings had significantly lower α-tocopherol plasma concentrations
than nestlings of the other species (both P < 0.001). Adult male ospreys and white-tailed sea eagles had significantly higher α-tocopherol concentrations compared to
adult females (both P < 0.005). Adult ospreys and northern goshawks had significantly higher α-tocopherol plasma concentrations compared to their
nestlings (both P < 0.001). In adult female northern goshawks, plasma concentrations of α-tocopherol increased significantly before egg laying
(P < 0.001). These results demonstrate α-tocopherol plasma concentrations in birds of prey to be species specific and influenced
by age and reproductive status. 相似文献
9.
Karel Weidinger 《Polar Biology》1997,17(5):469-472
Timing and duration of the breeding cycle of the Cape petrel Daption capense were studied during two breeding seasons (1990/1991 and 1991/1992) at Nelson Island, South Shetland Islands, Antarctica.
In 1991/1992 the copulatory period extended over 53 days, with median date and a peak about 28 and 19 days respectively, before
the median date of laying. Laying began 85 days after arrival, with mean (= median) date on 2 December (SD = 2.5 days). The
distributions of laying, hatching and fledging dates showed a similar degree of synchrony and did not differ between years.
Incubation and chick period were equally long (46 days), the former being less variable (coefficient of variation = 2.8% and
4.6%, respectively). Mean completed nesting cycle (92 days) was about 2 days shorter at Nelson Island than elsewhere and tended
to shorten as the breeding season progressed. Its mean length represented 86% of the whole nesting period (107 days), which
in turn represented 56% of the period of continuous colony attendance. Timing and duration of nesting stages did not differ
between colonies or sets of nests subjected to various levels of disturbance.
Received: 8 July 1996 / Accepted: 11 November 1996 相似文献
10.
Meal size of chinstrap penguins (Pygoscelis antarctica) was estimated through weighing adult breeders before and after food transfer during the crèche phase. Mean meal size delivered
by each parent was 630.2 ± 178.3 g and was independent of breeding date, number of chicks and sex. Only body size as estimated
by flipper length had a significant effect on meal size, suggesting an advantage of large body size which allows maximization
of food carried per visit.
Received: 22 September 1997 / Accepted: 16 December 1997 相似文献
11.
Zhang X Fei Y Zhang M Wei D Li M Ding W Yang J 《Biological trace element research》2008,121(3):233-242
Insulin plays an important role in bone prevention of diabetic osteoporosis, but little is known about the relation between
the bone mineral density (BMD) increase and the change of mineral element content after treated with insulin. To address this
problem, male Wistar rats were randomly divided into three groups: normal group (n = 6), streptozotocin-induced diabetic group (n = 5), and streptozotocin-induced diabetic group with insulin treatment (n = 5). The femoral BMD was measured by dual energy X-ray absorptiometry, and the element content was determined by inductively
coupled plasma atomic emission spectrometry (ICP-AES). The results showed that the femoral BMD in diabetic group was significantly
lower than that in normal group (P < 0.01) but restored by insulin treatment (P < 0.01 vs diabetic group). ICP-AES analysis revealed that the element content of calcium (Ca), phosphorous (P), magnesium
(Mg), strontium (Sr), and potassium (K) in diabetic group were remarkably lower than those in normal group (P < 0.01) but only Ca, P, and Mg content were significantly increased compared with diabetic group (P < 0.05) after insulin treatment. However, no significant differences were observed in element zinc (Zn) content among three
groups. Our findings suggested that the loss of Ca, P, Mg, Sr, and K content accounted for the lower BMD in streptozotocin-induced
diabetes rats, insulin treatment could restore BMD by increasing the content of Ca, P, and Mg. 相似文献
12.
The mortality of Sandwich tern Sterna sandvicensis chicks held in enclosures was studied in colonies on Griend, in the Dutch Wadden Sea, from 1992 to 1999, and on Hirsholm, in the Danish Kattegat, in 1997. Survival of chicks until fledging was 73% for chicks hatching from first-laid eggs or single-egg clutches and 59–64% for partially hatched two-egg clutches, whereas 6% of second hatchlings survived until fledging. Less than 2% of all two-chick broods actually fledged two chicks. Because 18% of the two-egg clutches only hatched one egg, 7% of fledglings of two-egg clutches originated from a second-laid egg. In nests where both eggs hatched, the number of chicks was usually reduced soon after hatching. Within five days of hatching more than 50% of the second hatchlings died of starvation or were preyed upon. It seems that overproduction commonly occurs in Sandwich terns and that investment in a surplus egg mainly serves as an insurance mechanism. On Griend and Hirsholm, chick productivity of two-egg clutches was somewhat higher than for one-egg clutches. Undernourishment was an important cause of death, either directly by starvation or by selective predation of chicks in poor condition. This, in combination with earlier, studies suggests that Sandwich tern parents on Griend are exposed to severe food stress. 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.
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
15.
Visser GH Boon PE Meijer HA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2000,170(5-6):365-372
The Doubly Labeled Water (DLW) method was validated against respiration gas analysis in growing Japanese Quail chicks (between
1 week and 3 weeks of age) as well as in birds after having achieved sexual maturity (7 weeks of age). A comparison was made
between a strain selected for high growth rates (P-strain, n=18), and a non-selected strain (C-strain, n=18). Relative growth rates of individual chicks during the measurement ranged from −13.8% day−1 to 23.1% day−1. When employing a single-pool model (eq. 34, Lifson and McClintock 1966), it was found that the relative error of the DLW
method was sensitive to assumptions concerning fractional evaporative water loss. The best fit was obtained after taking a
fractional evaporative water loss value of 0.33. When applying this value for all chicks, it was found that neither strain,
relative growth rate of the chick during measurement, nor age significantly contributed to the explained variance. When employing
two-pool models, it was found that the DLW method significantly underestimated the true rates of CO2 production at all assumed levels of fractional evaporative water loss. Based on an evaluation of DLW validation studies in
growing shorebirds, terns, and quail we recommend Speakman's Eq. 7.17 (Speakman 1997) for general use in young birds.
Accepted: 14 April 2000 相似文献
16.
P. J. Edmunds 《Coral reefs (Online)》2000,19(1):69-74
To determine what happens to scleractinian corals that have been killed by black band disease (BBD), massive corals with
BBD were monitored for 11 years on a shallow reef (<10 m depth) in St. John, US Virgin Islands. Small quadrats (0.039 m2) were used to compare the rates of scleractinian recruitment to the skeletons of corals killed by either BBD or physical
disturbance (Hurricane Hugo 1989). Coral recruitment was also quantified on the adjacent fringing reef using larger quadrats
(0.25 m2) to detect possible biases associated with using small, permanent quadrats to assess recruitment to BBD-killed corals. Of
28 tagged colonies with BBD in 1988, 43% were lost to Hurricane Hugo in 1989, 7% were lost to unknown causes between 1991
and 1992, and 14 were monitored annually for 11 years; of these, 71% were dead and still in their original growth position
in 1998. Between 1988 and 1997, corals recruited to the BBD-killed surfaces at a rate of 1.1 ± 0.3 recruits · 0.039 m−2 · decade−1 (mean ± SE, n = 14), although mortality reduced the density to 0.3 ± 0.2 recruits · 0.039 m−2 by 1997. The rate of recruitment and the taxonomic composition of the coral recruits to BBD-killed corals were indistinguishable
statistically from those to corals killed by Hurricane Hugo. This demonstrates that BBD creates space that is functionally
the same as other dead coral surfaces in providing a substratum for coral recruitment. However, because coral recruits are
dispersed widely, clumped in distribution and temporally variable in density on the fringing reef as a whole, it is unlikely
that they will be found on monitored coral colonies that have been killed by BBD. While this hypothesis is consistent with
the higher density of recruits on the fringing reef compared with BBD-killed corals, further studies are required to investigate
alternative explanations such as the role of substratum age in favoring recruitment to surfaces other than those killed recently
by BBD.
Accepted: 26 August 1999 相似文献
17.
We tested a staining method on uteri for counting placental scars on red fox. We estimated reproduction parameters on 358
females collected in three study areas in western France from 1st February 2002 to 31st January 2005. Placental scars (n = 103) were described by macroscopic examinations using the following variables: (1) the width and (2) the aspect of placental
scars, (3) the abundance of macrophages or the presence of blood, (4) the presence of swellings, (5) the presence and colour
of a central band and (6) the presence and colour of lateral bands. A factorial correspondence analysis showed strong associations
between the month when scars were examined and categories of variables. Staining on placental scars made macrophages more
visible, facilitating identification of ‘active’ placental scars, i.e. related to the last pregnancy. However, distinction
between placental scars due to earlier pregnancies and resorptions was not possible. The staining method used provides a standard
that could be useful for obtaining comparable and repeatable results. The mean number of placental scars was 4.85 ± 1.46 (n = 103) per vixen. The mean number of embryos per vixen was 4.66 ± 1.35 (n = 68) for yearlings and 5.53 ± 1.50 (n = 96) for older females. Including percentages of barren vixens, the total population productivity was significantly smaller
for yearlings (3.62 ± 1.86, n = 158) than for older females (4.28 ± 1.75, n = 186). We discuss these results in relation to fox densities, culling and food availability. 相似文献
18.
Frequency of Antibiotic Resistance in a Swine Facility 2.5 Years After a Ban on Antibiotics 总被引:1,自引:0,他引:1
The addition of antibiotics to livestock feed has contributed to the selection of antibiotic-resistant bacteria in concentrated
animal feeding operations and agricultural ecosystems. The objective of this study was to assess the occurrence of resistance
to chlortetracycline and tylosin among bacterial populations at the Swine Complex of McGill University (Province of Quebec,
Canada) in the absence of antibiotic administration to pigs for 2.5 years prior to the beginning of this study. Feces from
ten pigs born from the same sow and provided feed without antibiotic were sampled during suckling (n = 6 for enumerations, n = 10 for PCR), weanling (n = 10 both for PCR and enumerations), growing (n = 10 both for PCR and enumerations), and finishing (n = 10 both for PCR and enumerations). The percentage of chlortetracycline-resistant anaerobic bacterial populations (TetR) was higher than that of tylosin-resistant anaerobic bacterial populations (TylR) at weanling, growing, and finishing. Prior to the transportation of animals to the slaughterhouse, resistant populations
varied between 6.5 and 9.4 Log colony-forming units g humid feces−1. In all pigs, tet(L), tet(O), and erm(B) were detected at suckling and weanling, whereas only tet(O) was detected at growing and finishing. The abundance of tet(O) was similar between males and females at weanling and growing and reached 5.1 × 105 and 5.6 × 105 copies of tet(O)/ng of total DNA in males and females, respectively, at finishing. Results showed high abundances and proportions of TetR and TylR anaerobic bacterial populations, as well as the occurrence of tet and erm resistance genes within these populations despite the absence of antibiotic administration to pigs at this swine production
facility since January 2007, i.e., 2.5 years prior to the beginning of this study. This work showed that the occurrence of
bacterial resistance to chlortetracycline and tylosin is high at the Swine Complex of McGill University. 相似文献
19.
Marzec-Wróblewska U Kamiński P Lakota P Szymański M Wasilow K Ludwikowski G Kuligowska-Prusińska M Odrowąż-Sypniewska G Stuczyński T Michałkiewicz J 《Biological trace element research》2011,143(1):167-177
The aim of the present study was to measure zinc (Zn) and iron (Fe) concentration in human semen and superoxide dismutase
(SOD) activity in seminal plasma and correlate the results with sperm quality. Semen samples were obtained from men (N = 168) undergoing routine infertility evaluation. The study design included two groups based on the ejaculate parameters.
Group I (n = 39) consisted of males with normal ejaculate (normozoospermia), and group II (n = 129) consisted of males with pathological spermiogram. Seminal Zn and Fe were measured in 162 samples (group I, n = 38; group II, n = 124) and SOD activity in 149 samples (group I, n = 37; group II, n = 112). Correlations were found between SOD activity and Fe and Zn concentration, and between Fe and Zn concentration. SOD
activity was negatively associated with volume of semen and positively associated with rapid progressive motility, nonprogressive
motility, and concentration. Negative correlation was stated between Fe concentration and normal morphology. Mean SOD activity
in seminal plasma of semen from men of group I was higher than in seminal plasma of semen from men of group II. Fe concentration
was higher in teratozoospermic males than in males with normal morphology of spermatozoa in group II. Our results suggest
that Fe may influence spermatozoa morphology. 相似文献
20.
Vaibhav Jain Ashish Pandey Shikhar Gupta C. Gopi Mohan 《Journal of molecular modeling》2010,16(4):669-676
Asthma is an inflammatory disease of the lungs. Clinical studies suggest that eotaxin and chemokine receptor-3 (CCR3) play
a primary role in the recruitment of eosinophils in allergic asthma. Development of novel and potent CCR3 antagonists could
provide a novel mechanism for inhibition of this recruitment process, thereby preventing asthma. With the intention of designing
new ligands with enhanced inhibitor potencies against CCR3, a 3D-QSAR CoMFA study was carried out on 41 4-benzylpiperidinealkylureas
and amide derivatives. The best statistics of the developed CoMFA model were r
2 = 0.960, rcv2 = 0.589 r_{cv}^2 = 0.589 , n = 32 for the training set and rpred2 = 0.619 r_{pred}^2 = 0.619 , n = 9 for the test set. The generated 3D-QSAR contribution maps shed some light on the effects of the substitution pattern
related to CCR3 antagonist activity. 相似文献