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11.
Data on patterns of systematic and ocassional hunting of birds, mammals, reptiles, mollusks and insects by Stumptail macaques are reported for a period of ten months. Systematic hunting of water snails, terrestrial spiders, and land worms was conducted by all age classes, except infants, and both sexes. Of the occasional hunting of birds, large lizards, large frogs, and field mice, the adult females conducted 70%, the adult males 12%, the two year old females 12%, and the two year old males 6%. The differences between males and females were statistically significant (.05 confidence level). Females dominated the hunt and were more interested in meateating than the males. This contrasts strikingly with the data reported for baboons and chimpanzees in which the males dominate the hunt. Of all the prey hunted ocassionally, 76% was shared. The differences between shared and not sared prey were statistically significant (.05 confidence level). All age classes, including infants, participated in meat-sharing. Three types of meat-sharing are described: mother-offspring, hunter-close-friend, and piece-dropping. The prey was shared with genetic relatives, and with close and sistant friends in this order. Pearson’s correlation coeficients between rank of hunter and number of hunts and between rank of hunter and number of individuals with whom the prey was shared yielded +.866 and +.890 respectively. Meat-sharing seems to be similar to that observed for baboons but some differences exist between baboons and chimpanzees on the one hand and Stumptails on the other. Dominance relations in our Stumptails seem to act as the context determining the direction and the type of sharing. An increase in hunting activity during the study period is suggested to be the result of the prey’s migratory and breeding patterns, of environmental changes, and of the high activity scores and physiological states of the adult-females in the troop. Although not hunted, reactions to snakes, iguanas, scorpions, and gulls are also described. This work was supported by grants from Behavioral Sciences Foundation and by NSF Grant No. GB-42235.  相似文献   
12.
The blue-green alga Agmenellum quadruplicatum (strain PR6) has been used to prepare photobiosynthetically 13C-labeled d-glucose, 2-O-(α-d-glucopyranosyl)-glyceric acid (glucosylglycerate), 2-hydroxy-1-(hydroxymethyl)ethyl α-d-gluco-pyranoside (glucosylglycerol), and α-d-glueopyranosyl β-d-fructofuranoside (sucrose). When grown to a cell density of 4.4 g.L-1 (dry weight) under nitrate-nitrogen limiting growth conditions for 120 h, the algal cells contained 38% of the dry-cell weight as(1 → 4)-α-d-glucan (amylose). About 1% of the dry-cell weight was glucosylglycerol, glucosylglycerate, and sucrose. Glutamate was obtained, together with carbohydrates of low molecular weight, when the cells were extracted with chloroform-methanol; d-glucose was recovered from the extracted cells by acid hydrolysis of the starch. The algae were grown by using 20 mol% [13C] carbon dioxide for preparation of labeled carbohydrates and for cellular component identification by whole-cell n.m.r. spectroscopy.  相似文献   
13.
—Alcohol:NAD oxidoreductase (EC 1.1.1.1) was studied in brain cortex, hypothalamus, cerebellum and midbrain of adult and immature rats, and in the whole encephalon of neonatal rats. The rats used in this study were (i) from a colony which has been given 12% (v/v) aqueous ethanol as the only fluid for 54 generations (‘E.F.’ rats); (ii) rats removed from this colony after the forty-eighth generation and thereafter fed water instead of the alcohol solution (‘E.F./H2O’ rats); and (iii) normal rats. Enzyme activity in the 20,000 g supernatant of tissue homogenates was measured by the method of Raskin and Sokoloff. Activity was found to be highest in neonatal rat brain and to decrease as the age increased. Activity in the hypothalamus of adult E.F. rats was significantly higher than that found in the same region of adult E.F./H2O rats. Immature rat cerebellum alcohol:NAD oxidoreductase activity was higher both in ‘E.F.’ and ‘E.F./H2O’ suggesting a possible genetic change be involved in this CNS region. It may be concluded that, with the exception of neonatal rats, ethanol consumption induces an increase in rat CNS alcohol :NAD oxidoreductase activity.  相似文献   
14.
Summary Esterase D phenotypes were determined in 1082 non-related individuals from the western region of Germany by agarose-gel electrophoresis. Gene frequencies were compared with previous data and all European populations studied so far agreed with the Hardy-Weinberg equilibrium. Mean gene frequencies for Europeans are: EsD 1 0.8888, EsD 2 0.1112.  相似文献   
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During exercise, the oxygen consumption and the production of free radicals increase and can lead to oxidative stress with a deleterious effect on cellular structures involved in physical activity. To evaluate the oxidative stress produced by exercise and the role of ascorbate as an antioxidant, venous blood samples were obtained from 44 thoroughbred racehorses, before and after a 1000+/-200-m race at maximum velocity. Fourteen of these horses were treated intravenously with 5 g of ascorbate before running. Antioxidant capacity (PAOC), endogenous and exogenous ascorbate concentration, total antioxidant reactivity (TAR), urate concentration, creatine kinase activity, protein concentration and thiobarbiturate reactive substances (TBAR) as oxidative stress indicators were measured in the plasma of some of these horses. PAOC, TAR and TBAR increased after the race, while plasma ascorbate and urate concentrations remained unchanged. Total plasma protein (TPP) concentrations increased in line with antioxidant capacity. As predicted, both the plasma ascorbate concentration and PAOC increased immediately after ascorbate administration, but was not modified after the race, such as TBAR. However, in both groups plasma creatine kinase activity increased after the race. These results would suggest that the administration of ascorbate could nullify the oxidative stress produced by exercise in thoroughbred racehorses, but could not prevent muscular damage.  相似文献   
18.
The helminths of 218 white-toothed shrews from 29 sites in 2 biotopes in the Albufera Natural Park (Valencia, Spain) were examined from July 1990 to August 1991. An association analysis of helminths occurring at a prevalence of more than 4% was carried out for 4 species of cestodes located in the intestine (Hymenolepis pistillum, H. scalaris, H. tiara, and Pseudhymenolepis redonica) and 3 species of nematodes (Pseudophysaloptera sp. located in the stomach, Stammerinema rhopocephala larvae in the intestine and abdominal cavity, and Porrocaecum sp. in the thoracic and abdominal cavities). Bivariate (species pairs) versus multivariate analyses (associations within the entire set of species) were performed of presence-absence and of quantitative records (influence of intensity on associations). The associations were evaluated with respect to the sex and age of the host and to the sampling date and sites. The host and environment played a limited role, and the major determinant of species assemblage was phylogenetic. Positive associations were found among both the cestodes and the nematodes, whereas negative associations were found between cestodes and nematodes. The type of life cycle was probably the second greatest determinant of species associations. Nematodes using shrews as a paratenic host or as their definitive host were both positively associated.  相似文献   
19.

Background

Anxiety disorders have been linked to an increased risk of incident coronary heart disease in which inflammation plays a key pathogenic role. To date, no studies have looked at the association between proinflammatory markers and agoraphobia.

Methods

In a random Swiss population sample of 2890 persons (35-67 years, 53% women), we diagnosed a total of 124 individuals (4.3%) with agoraphobia using a validated semi-structured psychiatric interview. We also assessed socioeconomic status, traditional cardiovascular risk factors (i.e., body mass index, hypertension, blood glucose levels, total cholesterol/high-density lipoprotein-cholesterol ratio), and health behaviors (i.e., smoking, alcohol consumption, and physical activity), and other major psychiatric diseases (other anxiety disorders, major depressive disorder, drug dependence) which were treated as covariates in linear regression models. Circulating levels of inflammatory markers, statistically controlled for the baseline demographic and health-related measures, were determined at a mean follow-up of 5.5 ± 0.4 years (range 4.7 – 8.5).

Results

Individuals with agoraphobia had significantly higher follow-up levels of C-reactive protein (p = 0.007) and tumor-necrosis-factor-α (p = 0.042) as well as lower levels of the cardioprotective marker adiponectin (p = 0.032) than their non-agoraphobic counterparts. Follow-up levels of interleukin (IL)-1β and IL-6 did not significantly differ between the two groups.

Conclusions

Our results suggest an increase in chronic low-grade inflammation in agoraphobia over time. Such a mechanism might link agoraphobia with an increased risk of atherosclerosis and coronary heart disease, and needs to be tested in longitudinal studies.  相似文献   
20.
During the EPOS leg 2 cruise of the RV Polarstern, carried out in late austral spring of 1988–1989, the composition of phytoplankton in relation to the distribution of hydrographic parameters was studied in four successive transects carried out along 49°W and 47°W, across the Weddell-Scotia Confluence (WSC) and the marginal ice zone (which overlapped in part). In all transects, a maximum of phytoplankton biomass was found in the WSC, in surface waters stabilized by ice melting. Different phytoplankton assemblages could be distinguished. North of the Scotia Front (the northern limit of the WSC) diatoms with Chaetoceros neglectus, Nitzschia spp. and (Thalassiosira gravida) dominated the phytoplankton community. This assemblage appeared to have seeded a biomass maximum which occupied, during the first transect, an area of the WSC, south of the Scotia Front. The southernmost stations of the first transect and all the stations to the south of the Scotia Front in the other transects were populated by a flagellate assemblage (with a cryptomonad, Pyramimonas spp. and Phaeocystis sp.) and an assemblage of diatoms (Corethron criophilum and Tropidoneis vanheurkii among others) associated to the presence of ice. During the last three transects, the flagellate assemblage formed a bloom in the low salinity surface layers of the WSC zone. The bulk of the biomass maximum was formed by the cryptomonad which reached concentrations up to 4×106 cells l–1 towards the end of the cruise. Multivariate analysis is used to summarize phytoplankton composition variation. The relationships between the distribution of the different assemblages and the hydrographic conditions indicate that the change of dominance from diatoms to flagellates in the WSC zone was related to the presence of water masses from different origin.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundation  相似文献   
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