共查询到20条相似文献,搜索用时 31 毫秒
1.
E. Stoupel J. Abramson S. Domarkiene M. Shimshoni J. Sulkes 《International journal of biometeorology》1997,40(2):113-116
The influence of solar activity (SA) and geomagnetic activity (GMA) on human homeostasis has long been investigated. The
aim of the present study was to analyse the relationship between monthly proton flux (>90 MeV) and other SA and GMA parameters
and between proton flux and temporal (monthly) distribution of total and cardiovascular-related deaths. The data from 180
months (1974–1989) of distribution in the Beilinson Campus of the Rabin Medical Centre, Israel, and of 108 months (1983–1991)
from the Kaunas Medical Academy, were analysed and compared with SA, GMA and space proton flux (>90 MeV). It was concluded:
(1) monthly levels of SA, GMA and radiowave propagation (Fof2) are significantly and adversely correlated with monthly space
proton flux (>90 MeV); (2) medical-biological phenomena that increase during periods of low solar and/or geomagnetic activity
may be stimulated by physical processes provoked by the concomitant increase in proton flux; (3) the monthly number of deaths
related (positively or negatively) to SA are significantly and adversely related to the space proton flux (>90 MeV).
Received: 14 January 1996 / Accepted: 14 October 1996 相似文献
2.
Horiguchi T Ohta Y Nishikawa T Shiraishi F Shiraishi H Morita M 《Cell biology and toxicology》2008,24(6):553-562
To clarify how tributyltin (TBT) and triphenyltin (TPT) interact with the retinoid X receptor (RXR) to induce growth of male
sex organs in female gastropods, we treated female rock shells (Thais clavigera) with three different concentrations (0.1, 1, or 5 μg/g wet wt) of 9-cis-retinoic acid (9CRA) or with a single concentration (1 μg/g wet wt) of TBT, TPT, or fetal bovine serum (as a control). The
effects of each treatment were measured as the incidence of imposex, the length of the penis-like structure, and the vas deferens
sequence (VDS) index. 9CRA induced imposex in a dose-dependent manner; imposex incidence was significantly higher in the rock
shells that received 1 (P < 0.05) or 5 μg (P < 0.001) 9CRA than in the controls. After 1 month, the rock shells treated with 5 μg 9CRA exhibited substantial growth of
the penis-like structure that was not as evident in the other treated shells. The length of the structure differed between
the 0.1- and 5-μg 9CRA treatment groups (P < 0.05) but not between the 1- and 5-μg 9CRA treatment groups (P > 0.05). Compared with the control, the VDS index increased significantly in the 1- (P < 0.05) and 5-μg (P < 0.001) 9CRA groups. The penis-like structures behind the right tentacle in female rock shells treated with 5 μg 9CRA were
essentially the same as the penises and vasa deferentia of normal males and of TBT-treated or TPT-treated imposexed females.
These results further support the hypothesis that imposex in gastropods could be mediated by RXR. 相似文献
3.
Influence of local geomagnetic storms on arterial blood pressure 总被引:1,自引:0,他引:1
This study attempts to assess the influence of local geomagnetic storms at middle latitudes on some human physiological parameters. The blood pressure (bp), heart rate and general well-being of 86 volunteers were measured, the latter by means of a standardised questionnaire, on work days in autumn, 2001 (1 Oct to 9 Nov), and in spring, 2002 (8 April to 28 May). These timespans were chosen as periods of maximal expected geomagnetic activity (GMA). Altogether, 2799 recordings were obtained and analysed. A four factor analysis of variance (MANOVA) was employed to check the significance of the influence of four factors (local GMA level; sequence of the days of measurements covering up to 3 days before and after geomagnetic storms; sex and the presence of medication) on the physiological parameters under consideration. Post hoc analysis was performed to elicit the significance of differences in the factors' levels. Arterial bp was found to increase with the increase of the GMA level, and systolic and diastolic bp were found to increase significantly from the day before till the second day after the geomagnetic storm. These effects were present irrespective of sex and medication. 相似文献
4.
Mi-Young Oh Sang Beum Lee Deuk-Hee Jin Yong-Ki Hong Hyung-Joo Jin 《Journal of applied phycology》2010,22(4):453-458
We determined the structure of two compounds, namely, 5,8,11,14,17-eicosapentaenoic acid (EPA) and di-n-octylphthalate (DnOP), which have algicidal activity against the toxic dinoflagellate, Cochlodinium polykrikoides. The polyunsaturated fatty acid EPA and the anthropogenic DnOP were isolated from the MeOH extract of the red alga Corallina pilulifera. We also found that a commercial EPA has algicidal activity identical to that of the EPA purified from C. pilulifera. At low inoculum (5.0 × 102 cells mL−1), the highest algicidal activity of a commercial EPA exhibited approximately 92.6% algicidal activity after 1 h and 96.8%
after 6 h treatment at 6 μg mL−1, respectively. At high inoculum (1.0 × 104 cells mL−1), the strongest algicidal activity of EPA showed 69.5% after 1 h and 75.5% algicidal activity after 6 h treatment at 6 μg
mL−1, respectively. However, EPA did not show algicidal activity against several microalgae used in aquaculture such as Pavlova lutheri, Tetraselmis suecica, Isochrysis galbana, and Nannochloris oculata for 6 h treatment at 6 μg mL−1. The algicidal activity of the five red tide strains to EPA (3 μg mL−1) showed about 86.6%, 86.6%, and 67.3% algicidal activity against Skeletonema costatum, Chaetoceros curvisetus, and C. polykrikoides after 1 h treatment at low inoculum (5.0 × 102 cells mL−1), respectively, but not against Prorocentrum minimum and Scrippsiella trochoidea. We concluded that EPA might be useful as a controlling agent of harmful algal blooms. 相似文献
5.
J. M. Fernández Sevilla E. Molina Grima F. García Camacho F. G. Acién Fernández J. A. Sánchez Pérez 《Applied microbiology and biotechnology》1998,50(2):199-205
Eicosapentaenoic acid (EPA) productivity from continuous cultures of the marine microalga Isochrysis galbana was studied, taking into account the irradiance on the reactor surface, that is, the photolimitation/photoinhibition regime
to which the cells are exposed. Experiments were conducted under a wide variety of operating conditions. The dilution rate
ranged from 0.005 h−1 to 0.040 h−1 at five external irradiances (820, 1620, 2050, 2450 and 3270 μmol photons m−2 s−1) covering photolimited to photoinhibited growth. Under these conditions, the specific growth rate (μ) was found to be the
main factor influencing EPA content (ranging from 2.35% to 5.23% dryweight) and productivity (up to 0.88 mg l−1 h−1). The fatty acid content was not significantly affected by the external irradiance, but was influenced by the state of growth
of the microalga, depending on whether the light regime was photolimiting or photoinhibiting. It might be suggested that light
should no longer be considered an isolated factor affecting EPA synthesis, but an indirect influence through the photolimitation/photoinhibition
regime and growth rate. At a given dilution rate, EPA content and biomass concentration are lower under photoinhibiting external
irradiances than those corresponding to photolimiting conditions, and consequently EPA productivity decays. Since the effect
of photoinhibition is less marked at high biomass concentration, a strategy to optimize EPA productivity from microalgal cultures
could consist of reducing the dilution rate when the external irradiance increases above the phoinhibition threshold.
Received: 16 January 1998 / Revised revision: 27 March 1998 / Accepted: 27 March 1998 相似文献
6.
Jone Vencloviene Ruta Babarskiene Rimvydas Slapikas Gintare Sakalyte 《International journal of biometeorology》2013,57(5):797-804
It has been found that solar and geomagnetic activity affects the cardiovascular system. Some evidence has been reported on the increase in the rate of myocardial infarction, stroke and myocardial infarction related deaths during geomagnetic storms. We investigated the association between cardiovascular characteristics of patients, admitted for myocardial infarction with ST elevation (STEMI), and geomagnetic activity (GMA), solar proton events (SPE), solar flares, and meteorological variables during admission. The data of 1,979 patients hospitalized at the Hospital of Lithuanian University of Health Sciences (Kaunas) were analyzed. We evaluated the association between environmental variables and patient’s characteristics by multivariate logistic regression, controlling patient’s gender and age. Two days after geomagnetic storms the risk of STEMI was over 1.5 times increased in patients who had a medical history of myocardial infarction, stable angina, renal or pulmonary diseases. The dose–response association between GMA level and STEMI risk for patients with renal diseases in history was observed. Two days after SPE the risk of STEMI in patients with stable angina in anamnesis was increased over 1.5 times, adjusting by GMA level. The SPE were associated with an increase of risk for patients with renal diseases in history. This study confirms the strongest effect of phenomena in the Sun in high risk patients. 相似文献
7.
Felix Scholkmann Giuseppe Miscio Roberto Tarquini Alberto Bosi Rosa Rubino Lazzaro di Mauro 《Chronobiology international》2016,33(9):1136-1147
Recently, we have shown that the contents of total nucleated cells (TNCs) and CD34+ hematopoietic stem and progenitor cells (CD34+ HSPCs) as well as the cord blood volume (CBV) in umbilical cord blood (UCB) show a circadecadal (~10 years) rhythm of oscillation. This observation was based on an analysis of 17,936 cord blood donations collected during 1999–2011. The aim of the present study was to investigate whether this circadecadal rhythm of oscillation in TNCs, CD34+ HSPCs and CBV is related to geomagnetic activity. For the analysis, the yearly averages of TNCs, CD34+ HSPCs and CBV in UCB were correlated with geomagnetic activity (Dcx index). Our analysis revealed that (i) all three UCB parameters were statistically significantly correlated with the level of geomagnetic activity, (ii) CBV showed a linear correlation with the Dcx index (r = 0.5290), (iii) the number of TNCs and CD34+ HSPCs were quadratic inversely correlated with the Dcx index (r = ?0.5343 and r = ?0.7749, respectively). Furthermore, (iv) CBV and the number of TNCs were not statistically significantly correlated with the number of either modest or intense geomagnetic storms per year, but (v) the number of CD34+ HSPCs was statistically significantly correlated with the number of modest (r = 0.9253) as well as intense (r = 0.8683) geomagnetic storms per year. In conclusion, our study suggests that UCB parameters correlate with the state of the geomagnetic field (GMF) modulated by solar activity. Possible biophysical mechanisms underlying this observation, as well as the outcome of these findings, are discussed. 相似文献
8.
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
9.
The effects of elevated CO2 on plant biomass and community structure have been studied for four seasons in a calcareous grassland in northwest Switzerland.
This highly diverse, semi-natural plant community is dominated by the perennial grass Bromus erectus and is mown twice a year to maintain species composition. Plots of 1.3 m2 were exposed to ambient or elevated CO2 concentrations (n = 8) using a novel CO2 exposure technique, screen-aided CO2 control (SACC) starting in March 1994. In the 1st year of treatment, the annual harvested biomass (sum of aboveground biomass
from mowings in June and October) was not significantly affected by elevated CO2. However, biomass increased significantly at elevated CO2 in the 2nd (+20%, P = 0.05), 3rd (+21%, P = 0.02) and 4th years (+29%, P = 0.02). There were no detectable differences in root biomass in the top 8 cm of soil between CO2 treatments on eight out of nine sampling dates. There were significant differences in CO2 responsiveness between functional groups (legumes, non-leguminous forbs, graminoids) in the 2nd (P = 0.07) and 3rd (P < 0.001) years of the study. The order of CO2 responsiveness among functional groups changed substantially from the 2nd to the 3rd year; for example, non-leguminous forbs
had the smallest relative response in the 2nd year and the largest in the 3rd year. By the 3rd year of CO2 exposure, large species-specific differences in CO2 response had developed. For five important species or genera the order of responsiveness was Lotus corniculatus (+271%), Carex flacca (+249%), Bromus erectus (+33%), Sanguisorba minor (no significant CO2 effect), and six Trifolium species (a negative response that was not significant). The positive CO2 responses in Bromus and Carex were most closely related to increases in tiller number. Species richness was not affected by CO2 treatment, but species evenness increased under elevated CO2 (modified Hill ratio; P = 0.03) in June of the 3rd year, resulting in a marginally significant increase in species diversity (Simpson's index; P = 0.09). This and other experiments with calcareous grassland plants show that elevated atmospheric CO2 concentrations can substantially alter the structure of calcareous grassland communities and may increase plant community
biomass.
Received: 12 July 1997 / Accepted: 14 September 1998 相似文献
10.
The availability of most edible ectomycorrhizal mushrooms depends on their natural fructification. Sporocarp formation of
these fungi is linked to habitat characteristics and climate conditions, but these data alone do not explain all the trends
of fungal fruiting and dynamics. It could be hypothesized that the amount of soil mycelia could also be related to the production
of carpophores. Soil samples (five cylinders of 250 cm3 per plot) were taken monthly, from September to November, in five fenced permanent plots (5 × 5 m) in Pinar Grande (Soria,
Spain), a Pinus sylvestris stand situated in the north of the Sistema Ibérico mountain range. Plots were chosen to establish a gradient of Boletus edulis productivity from 0 to 38.5 kg/ha year, according to the mean fresh weight of sporocarps collected during the last 10 years.
B. edulis ectomycorrhizal root tips were identified in each soil sample according to its morphology and counted. DNA extractions were
performed with the PowerSoilTM DNA Isolation Kit and quantification of extraradical soil mycelium by real-time polymerase chain reaction using specific
primers and a TaqMan? probe. The concentration of soil mycelium of B. edulis (mg mycelium/g soil) did not differ significantly between plots (p = 0.1397), and sampling time (p = 0.7643) within the fructification period. The number of mycorrhizal short roots per soil volume showed significant differences
between the plots (p = 0.0050) and the three sampling times (p < 0.0001). No significant correlation between the number of mycorrhizas and the productivity of the plot (kg of B. edulis/ha year) was detected (p = 0.615). A statistically significant positive correlation (p = 0.0481) was detected between the concentration of mycelia of B. edulis in the soil samples and the presence of short roots mycorrhizal with B. edulis in these samples. The productivity of the plots, in terms of sporocarps produced during the last 10 years, was not correlated
either with the concentration of soil mycelium or with the presence or abundance of ectomycorrhizas. 相似文献
11.
The Alternaria mycotoxin tenuazonic acid (TA) was quantified in fruit juices (n = 50), cereals (n = 12) and spices (n = 38) using a recently developed stable isotope dilution assay (SIDA). [13 C6,15 N]-TA was used as the internal standard. Method validation revealed low limits of detection (LODs) of 0.15 μg/kg (fruit juices),
1.0 μg/kg (cereals) and 17 μg/kg (spices). The respective limits of quantitation were about three times higher. Recovery was
about 100% for all matrices. The precision (relative standard deviation of replicate analyses of naturally contaminated samples)
was 4.2% (grape juice; 1.7 μg/kg), 3.5% (whole wheat flour; 36 μg/kg) and 0.9% (curry powder; 215 μg/kg). The median content
of TA in the analyzed samples was 1.8 μg/kg (fruit juices), 16 μg/kg (cereals) and 500 μg/kg (spices). Positive samples amounted
to 86% (fruit juices), 92% (cereals) and 87% (spices). 相似文献
12.
Cell density and fatty acid (FA) content of Pavlova lutheri and Chaetoceros muelleri were analysed in a continuous algal production system (250-L bags) with reduced diameter. The cell density and FA content
and composition in the algal production system were determined in replicate bags over a period of 5 weeks. The results showed
that the cell density and essential FAs increased during the experiment for both species. After 5 weeks the mean cell numbers
had increased to 6.0 ± 0.3 × 106 cells mL−1 in the P. lutheri bags and 6.0 ± 0.4 × 106 cells mL−1 in the C. muelleri bags. The content of total FAs increased significantly (p < 0.05) in all of the bags during the experiment. At the end of the experiment the mean total FA content were 2.7 ± 0.3 pg cell−1 in the P. lutheri bags and 1.8 ± 0.1 pg cell−1 in the C. muelleri bags. Maximum total FA content registered was 3.0 pg cell−1 in one of the P. lutheri bags. The content of the essential FAs (ARA, EPA, DHA) increased over time in both of the species. At the end of the experiment
the content of EPA (0.6 ± 0.1 pg cell−1) and DHA (0.3 ± 0.0 pg cell−1) were highest in the P. lutheri bags, while ARA (0.1 ± 0.0 pg cell−1) was highest in C. muelleri. EPA and DHA constituted 22% and 11%, respectively, of total FA content in P. lutheri, while ARA constituted 6% of total FA content in C. muelleri. The results from this experiment indicate that flagellates such as P. lutheri perform better in narrow bags with improved light conditions, while diatoms like C. muelleri perform better in wider bags under light limitation. Implications for bivalve hatcheries are discussed. 相似文献
13.
We observed a group of capped langurs for 12 mo in the Pakhui Wildlife Sanctuary, Arunachal Pradesh, India. We recorded the
time of feeding on different food plant species, food categories, and the feeding heights of monkeys in trees. Capped langurs
spent 68% of their feeding time on leaves, 16% on flowers, and 16% on fruits. Feeding on leaves was consistently high (p < 0.01) during the year, with the highest feeding in May (85%) and the lowest in January (47%). The seasonal difference in
feeding on leaves is significant (p < 0.05): it was higher in summer and during monsoon. The feeding time on flowers was maximal (35%) in March and that on fruits
and seeds was minimal (38%) in January. Langurs ate 52 plant species throughout the year. The largest number of plants (6)
were species of Moraceae, and langurs spent more feeding time (20%) on them alone. The number of plants eaten per month varied
significantly (p < 0.05). Langurs ate Gmelina arborea, Albizzia lucida, Ficus glomereta, and Makania micrantha throughout the year. They spent 44% of their feeding time in terminal canopies and their average feeding height was 30–35 m.
This is the first study to examine the feeding ecology of capped langurs and provides baseline data for the species. 相似文献
14.
Essential hypertension (EH) is a major public health problem world over and in India. Recent data on EH in the population
of Chandigarh (Union Territory and capital of Punjab and Haryana States of India) revealed that the prevalence of EH has become
double in the last 30 years in the residents of Chandigarh (26.9 to 45.80% in the year 1968 and 2002). Zinc (Zn), copper (Cu),
magnesium (Mg), and manganese (Mn) in the serum are considered important in maintaining the human hypertension. The high Zn
intake was considered to increase the blood pressure (BP) and to affect the other mineral status in the body. Recent survey
on the trace metal status of different vegetables in the State of Punjab around Chandigarh (India) revealed that Zn level
is significantly higher (40 mg/kg or more in above ground vegetables and 120 mg/kg or above in underground vegetables) in
underground water-irrigated vegetables, but the levels of Cu and Mg are within prescribed limit. The present study was conducted
on Chandigarh population to evaluate the levels of Zn, Cu, Mg, and Mn in the blood and urine of normotensive (NT) control
and hypertensive (HT) subjects matched with number, age and sex. Atomic absorption spectrophotometer studies revaluated that
the levels of serum Zn, Mg, and Mn were significantly higher (p < 0.001), but the level of Cu was low in the HT subjects (BP = 160/93) compared to NT control (BP = 140/83). Higher levels
of urinary Zn, Cu, Mg, and Mn were observed in the HT subject vs NT control (p < 0.001). Positive correlations were evaluated between the levels of serum Zn, Mg, and Mn vs systolic and diastolic pressures
(DP and SP), respectively (r = 0.928, 0.863, 0.876, 0.808, 0.404, 0.326, p < 0.01), but negative and positive nonsignificant correlations between the serum Cu with SP and DP were recorded (r = −0.032, r = 0.024). Positive correlations were also evaluated between urinary levels of Zn, Cu, Mg, and Mn vs SP and DP (r = 0.718, 0.657, 0.750, 0.681, 0.630, 0.578, 0.516, 0.461, p < 0.01). Prevalence of essential hypertension may be due to higher Zn level in the food chain that makes the individuals vulnerable
to other diseases over the time related to essential hypertension. 相似文献
15.
Xiaomin Zhang Zengguang Xu Li Zhou Ying Chen Meian He Longxian Cheng Frank B. Hu Robert M. Tanguay Tangchun Wu 《Cell stress & chaperones》2010,15(5):675-686
Although immune reactions against heat shock proteins have been implicated in the pathogenesis of atherosclerosis, conflicting
associations between Hsp70, anti-Hsp70 antibody and coronary heart disease (CHD) have been reported. This study assessed whether
there is a significant association between extracellular human Hsp70, anti-Hsp70 antibody and acute coronary syndrome (ACS)
and stable angina (SA), and examined dynamic changes in Hsp70 and anti-Hsp70 antibody levels induced by acute myocardial infarction
(AMI). Plasma Hsp70 and anti-Hsp70 antibody levels in 291 patients with ACS (179 AMI, 112 unstable angina), 126 patients with
SA and 417 age and sex-matched healthy subjects, and in 40 patients after admission for AMI, and on day 2, 3, and 7 after
the onset of AMI were determined using enzyme-linked immunosorbent assays. Hsp70 levels were significantly higher in ACS and
SA and anti-Hsp70 antibody levels were only markedly lower in ACS than controls. After adjustment for traditional CHD risk
factors, increasing levels of Hsp70 were significantly associated with an increased risk and severity of ACS (P for trend < 0.001), whereas increasing levels of anti-Hsp70 antibody were associated with a decreased risk of ACS (P for trend = 0.0003). High levels of Hsp70 combined with low levels of anti-Hsp70 antibody had a joint effect on the risk
of ACS (OR, 5.14, 95% CI, 3.00-8.79; P < 0.0001). In patients with AMI, Hsp70 levels decreased rapidly from days 1-7 after onset, whereas anti-Hsp70 antibody levels
increased in patients with AMI. These findings suggest that higher Hsp70 levels or lower anti-Hsp70 antibody levels are independently
associated with a higher risk of ACS. Higher Hsp70 levels and lower anti-Hsp70 antibody levels combine to further increase
this risk. 相似文献
16.
A transposable element, Flipper, was isolated from the phytopathogenic fungus Botrytis cinerea. The element was identified as an insertion sequence within the coding region of the nitrate reductase gene. The Flipper
sequence is 1842 bp long with perfect inverted terminal repeats (ITRs) of 48 bp and an open reading frame (ORF) of 533 amino
acids, potentially encoding for a transposase; the element is flanked by the dinucleotide TA. The encoded protein is very
similar to the putative transposases of three elements from other phytopathogenic fungi, Fot1 from Fusarium oxysporum, and Pot2 and MGR586 from Magnaporthe grisea. The number of Flipper elements in strains of B. cinerea varied from 0 to 20 copies per genome. Analysis of the descendants of one cross showed that the segregation ratio of Flipper
elements was 2:2 and that the copies were not linked.
Received: 4 December 1996 / Accepted: 21 January 1997 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.
Enhancement of tessaric acid production in Tessaria absinthioides cell suspension cultures 总被引:1,自引:0,他引:1
The total production of the sesquiterpene tessaric acid (TA) by cell cultures of Tessaria absinthioides at day 25 of the culture period reached 0.086 mg g−1 DW, with intracellular accumulation accounting for 0.059 mg g−1 DW. Dimethylsulfoxide-induced permeabilization of the cells effected both total production and extracellular accumulation
of the sesquiterpene to reach levels of 148% and 271%, respectively. Cultures treated with elicitor preparations of Verticillum sp., Monodyctis cataneae, Acremonium sp., and Aspergillus niger produced TA at levels of 281%, 197%, 149%, and 139%, respectively. Treatment of cell suspension cultures with cis-(-)-jasmonic acid (5 μM) increased production to 267%, whereas jasmonic acid pretreatment and subsequent elicitation raised external tessaric acid
to 702%.
Received: 16 December 1998 / Revision received: 02 November 1999 / Accepted: 19 November 1999 相似文献
19.
Angela Margaret Sibbald Russell J. Hooper James E. McLeod Iain J. Gordon 《European Journal of Wildlife Research》2011,57(4):817-825
Disturbance to wildlife from human recreational activities is increasing as remote areas become accessible to greater numbers
of people. We used Global Positioning System tracking collars to monitor the movements of red deer (Cervus elaphus) stags (n = 8) in a herd whose feeding grounds lie close to a popular walking track in the Highlands of Scotland. The track is used
by around 20,000 walkers per year and is busiest in summer and at weekends. In a 2-year study, the locations of collared deer
were recorded at 2-h intervals on typically busy days (Sundays: mean number of walkers = 204) and quiet days (Wednesdays:
mean number of walkers = 49) during May and June. The deer were consistently further from the track on Sundays than Wednesdays
(371 vs 286 m) and moved greater distances between fixes (365 vs 308 m). The amount of time spent (percentage of total fixes)
in the small area of grassland closest to the track was lower on Sundays than Wednesdays (6% vs 13%). Although 97% of walkers
use the track during the day (between 0800 and 2000 h), there was no evidence of compensatory use of grassland at night, when
the deer moved to higher ground dominated by heather moorland. The results demonstrate that animals which appear to be habituated
to regular disturbance within their home territory may nevertheless alter their behaviour and potentially diet composition,
as a result of that disturbance. 相似文献
20.
Goulart Vincius D. L. R. Teixeira Camila P. Young Robert John 《European Journal of Wildlife Research》2010,56(4):641-649
In this study, we investigated what problems urban marmosets (Callithrix penicillata) face in a city environment through the analysis of responses to callouts (N = 348) made by the environmental police of Belo Horizonte, Minas Gerais, Brazil, in the period from 2002 to 2007. Our objective
was to characterise the problems faced by the marmosets and human city dwellers. The environmental police responded to two
types of callouts: (1) solicitation whereby a person called them to report a problem (N = 218); and (2) the report of a hurt or injured animal (N = 127). On average, one callout per week was made in relation to urban marmosets. We found no time of year effects in relation
to callouts, or any effect of gender or age of the person making the callout (P > 0.05). Furthermore, we found no environmental (e.g. percentage of “green area”) or socioeconomical variables (e.g. salary
levels) of the city’s administrative regions associated with callouts (P > 0.05). The majority of callouts resulted in the attempt to capture marmosets (N = 345), and usually, only one animal was captured (N = 309). Many of these animals were released into city forest fragments (N = 146). Some sick animals were sent to veterinary clinics (N = 25) whereas others or confiscated animals were sent to the government’s wildlife processing centre (N = 143). From this data, we were able to make a series of recommendation about how the management of urban marmosets could
be improved. 相似文献