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891.
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894.
We radio-tracked Myotis emarginatus in Upper Bavaria, Germany to identify the key-foraging habitats and to enable an adequate habitat management for this endangered species. The studied females foraged at a distance of up to 8.1 km around their colony roost. The average distance of the foraging area was 3.7 km, where 70% of foraging areas were located within a distance of 5 km and 90% within 6 km of the nurseries. Moreover, these bats spent about 75% of their foraging time within 5 km and 85% within a 6-km radius. To reach the foraging areas, the bats usually used riparian woodlands, hedges and tree lines as flight paths. Specifically, 46.9% of the foraging areas were located in forests, 24.5% in cow sheds, 18.4% in riparian woodlands along streams and 10.2% in fields, villages, orchards, hedges and groves on open land. On average, the bats foraged in forests for 56.2% of the time, during which habitat allocation was possible. In cow sheds the percentage was 29.2%, in riparian deciduous woodland 11.5% and in the other habitats 3.1%. Within forests M. emarginatus avoided foraging in spruce monocultures. Pure stands of spruce covered 45% of the total forest area, but only 10% of the foraging areas were located in this forest type. Deciduous forests on the other hand were much more common as foraging sites (40% versus 11%). Therefore, the availability of native deciduous forest and of fly-infested stables within a radius of 6 km around the colony roosts should be the focus of conservation concepts for M. emarginatus.  相似文献   
895.
One difficulty in the conservation of endangered wildlife is the lack of reliable information on its status. This lack of knowledge can often be attributed to financial and logistic constraints as well as the lack of trained personnel to collect data. We test a simple method to study bears in the southern Balkans by inspecting power poles, which are used by bears for marking and rubbing purposes. We created a network of barbed-wire fitted poles for the collection of hair samples, evenly distributed throughout six study areas. During 87 sampling sessions in the main study area, we collected 191 samples and identified six microsatellite loci that were variable enough for individual bear identification. The most and best-quality hair samples were collected during the mating period, and DNA was most successfully extracted from samples remaining <4 weeks in the field. In the six study areas, we identified 47 bears. An advantage of using power poles for hair sampling is their availability and accessibility; no bait is required, and the network can be easily set up. A drawback may be an unequal capture probability of sex and age classes of bears. Despite this limitation, using power poles proved to be a simple and cheap method for the noninvasive genetic study of bears that did not require any prior knowledge on habitat use and activity patterns. The method is suitable for large-scale surveys to estimate distribution and relative densities of bears and could also be applied for studying other species.  相似文献   
896.

The authors monitored five maternity colonies of Plecotus austriacus to obtain data about phenology, roosting, and emergence behaviour. The bats occupied their roosts between April and October, with maximum colony sizes in August. Roosting sites in the attic’s roof ridge and temperatures of 20–25°C were favoured. Also considering the small colony (maximum 59) and cluster sizes (maximum 13 bats), P. austriacus behaved less thermophilic than other attic-dwelling species. During low temperatures, the bats chose small crevice-like roosting sites to compensate for that; during daytime, many bats remained hidden in crevices. Emergence began approximately 30 min after sunset; the bats used multiple, preferably crevice-like openings. P. austriacus left its summer roosts comparatively late; renovation works should, therefore, not start before November. For monitoring purposes, we recommend two to three emergence countings outside the attics in early August during warm weather, alongside two attic inspections 1–2 h before emergence for offspring monitoring.

  相似文献   
897.
Prolylcarboxypeptidase (PRCP) is a serine protease that catalyzes the cleavage of C‐terminal amino acids linked to proline in peptides. It is ubiquitously expressed and is involved in regulating blood pressure, proliferation, inflammation, angiogenesis, and weight maintenance. To identify the candidate proximal target engagement markers for PRCP inhibition in the central nervous system, we profiled the peptidome of human cerebrospinal fluid to look for PRCP substrates using a MS‐based in vitro substrate profiling assay. These experiments identified a single peptide, with the sequence YPRPIHPA, as a novel substrate for PRCP in human cerebrospinal fluid. The peptide YPRPIHPA is from the extracellular portion of human endothelin B receptor‐like protein 2.  相似文献   
898.
Until recently little was known about the crop diversity in the Sultanate of Oman, situated at the NE tip of the Arabian Peninsula. Interdisciplinary research in the often millenia‐old oases provide evidence for their role as reservoirs for plant genetic resources of ancient varieties of wheat and banana. Two newly discovered banana clones show a highly efficient biochemical defense mechanisms against some of the most devastating pests and diseases of banana. If these mechanisms can be properly understood and exploited in breeding programs, may have major impact on the commercial production of edible banana.  相似文献   
899.
Recently, Salmonella enterica subsp. enterica serovar Saintpaul has increasingly been observed in several countries, including Germany. However, the pathogenic potential and epidemiology of this serovar are not very well known. This study describes biological attributes of S. Saintpaul isolates obtained from turkeys in Germany based on characterization of their pheno- and genotypic properties. Fifty-five S. Saintpaul isolates from German turkeys and turkey-derived food products isolated from 2000 to 2007 were analyzed by using antimicrobial agent, organic solvent, and disinfectant susceptibility tests, isoelectric focusing, detection of resistance determinants, plasmid profiling, pulsed-field gel electrophoresis (PFGE), and hybridization experiments. These isolates were compared to an outgroup consisting of 24 S. Saintpaul isolates obtained from humans and chickens in Germany and from poultry and poultry products (including turkeys) in Netherlands. A common core resistance pattern was detected for 27 German turkey and turkey product isolates. This pattern included resistance (full or intermediate) to ampicillin, amoxicillin-clavulanic acid, gentamicin, kanamycin, nalidixic acid, streptomycin, spectinomycin, and sulfamethoxazole and intermediate resistance or decreased susceptibility to ciprofloxacin (MIC, 2 or 1 μg/ml, respectively) and several third-generation cephalosporins (including ceftiofur and cefoxitin [MIC, 4 to 2 and 16 to 2 μg/ml, respectively]). These isolates had the same core resistance genotype, with blaTEM-1, aadB, aadA2, sul1, a Ser83→Glu83 mutation in the gyrA gene, and a chromosomal class 1 integron carrying the aadB-aadA2 gene cassette. Their XbaI, BlnI, and combined XbaI-BlnI PFGE patterns revealed levels of genetic similarity of 93, 75, and 90%, respectively. This study revealed that a multiresistant S. Saintpaul clonal line is widespread in turkeys and turkey products in Germany and was also detected among German human fecal and Dutch poultry isolates.Over the last few decades, the emergence and spread of antimicrobial agent-resistant zoonotic bacteria has become a serious public health concern (2, 23). The widespread use of antimicrobial agents for disease control, including at the farm level, has increased selection of antimicrobial agent-resistant Salmonella isolates (1, 23, 44). Food animals are considered an important reservoir for resistant bacteria. These animals and food products derived from them are traded worldwide, which contributes to the global spread of zoonotic agents and antimicrobial resistance. In the last few years, several monitoring activities were initiated in order to generate baseline data on antimicrobial resistance in bacteria isolated from livestock and food derived from animals that could be used in future assessments of the risk of antimicrobial resistance (10).According to European Union (EU) Zoonoses Regulation (EC) no. 2160/2003 on the control of Salmonella and other specified food-borne zoonotic agents, a European Community target for reducing the prevalence of Salmonella in turkey flocks had to be established. Consequently, EU Commission decision 2006/662/EC was released, and a baseline survey of the prevalence of Salmonella in turkey flocks was carried out in all European countries, including Germany, over a 1-year period starting on 1 October 2006 (http://www.efsa.europa.eu/EFSA/efsa_locale-1178620753812_1178706574172.htm). The main objective of this study was to estimate the prevalence of Salmonella in commercial flocks of turkeys. The data showed that at the EU level Salmonella enterica serovar Bredeney was the serovar reported most frequently for fattening turkey flocks and occurred in 17.2% of the samples from Salmonella-positive flocks (1,084 of 3,702 flocks were positive), followed by S. enterica serovar Hadar, S. enterica serovar Derby, and then S. enterica serovar Saintpaul (14.0%, 11.3%, and 10.4% of the samples from positive flocks, respectively). In this study, S. Saintpaul was detected in fattening turkeys in 12 countries, reflecting the wide spread of this serovar. Recently, S. Saintpaul has been increasingly observed in several countries, including Germany. According to Enter-Net reports (data on Salmonella human isolates identified by European national reference centers), for the last quarter of the year 2006 S. Saintpaul was the fourth most common serovar (1.6%) and, in contrast to the data for previous years, was one of the most frequent causes of human salmonellosis in Europe. After this, its prevalence was 1.2% and 0.6% in the first quarters of 2007 and 2008, respectively, among the Salmonella serotypes implicated in human disease (http://ecdc.europa.eu/en/publications/Pages/Surveillance_Reports.aspx). During the period from 2001 to 2009 in Germany, 463 cases of human salmonellosis related to S. Saintpaul (0.09% of all cases; the maximum prevalence was 0.15% in 2008, the prevalence was 0.1% in 2002, 2005, 2006, and 2009 and 0.06% in 2004, and the minimum prevalence was 0.05% in 2007) were reported to the Robert Koch Institute (Berlin, Germany) (www3.rki.de/SurvStat). In Germany, S. Saintpaul attracted public attention particularly in 1993, when it caused a nationwide food-borne outbreak (27). This serotype has often been related to outbreaks in other countries, and in 2008 it was implicated in a large multistate human outbreak associated with various vegetables in the United States (4).Previous studies showed that isolates of S. Saintpaul are often multidrug resistant (33, 35), but little is known about the mechanisms underlying antimicrobial resistance or about the pathogenic potential and epidemiology of isolates belonging to this serotype. The goals of this study were to obtain information about the resistance characteristics of isolates collected between 2000 and 2007 in Germany and to assess possible clonal relationships. The isolates used originated from turkey feces collected during the German Salmonella baseline study (in 2006 and 2007) or from diagnostic samples, including samples of turkey feces and turkey-related food products. These isolates were compared with German strains isolated from humans and chickens and with poultry strains isolated in Netherlands.  相似文献   
900.
Seedlings of the salt-tolerant plant grewia [Grewia tenax (Forssk.) Fiori] and the moderately salt-tolerant tamarind (Tamarindus indica L.) were grown under controlled conditions and treated daily with NaCl solutions to investigate mechanisms of tolerance to salinity. Leaf micromorphology, cuticular wax load, chlorophyll fluorescence and light remission, as well as antioxidative potential were evaluated. As confirmed by energy-dispersive X-ray microanalysis in both species, absorption of sodium and chlorine increased with rising NaCl concentration in the treatment solution. In parallel, accumulation of calcium in grewia leaves was strongly reduced, leading to less crystals of calcium oxalate in leaf tissue. In grewia the cuticular wax load, chlorophyll content, and electron transport rate (ETR) were significantly reduced by comparatively low NaCl concentrations. In tamarind, in contrast, wax load and ETR were not significantly affected, while the decrease of chlorophyll content was less pronounced. Measurements of the antioxidative capacity and the imbalance between values of lipophilic and hydrophilic extracts at different NaCl concentrations confirmed that grewia is more salt tolerant than tamarind. This higher tolerance degree seemed to be associated with grewias’ more efficient scavenging of free radicals and the regulation of the antioxidative potential in lipophilic and hydrophilic extracts.  相似文献   
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