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111.
112.
Auton A Fledel-Alon A Pfeifer S Venn O Ségurel L Street T Leffler EM Bowden R Aneas I Broxholme J Humburg P Iqbal Z Lunter G Maller J Hernandez RD Melton C Venkat A Nobrega MA Bontrop R Myers S Donnelly P Przeworski M McVean G 《Science (New York, N.Y.)》2012,336(6078):193-198
To study the evolution of recombination rates in apes, we developed methodology to construct a fine-scale genetic map from high-throughput sequence data from 10 Western chimpanzees, Pan troglodytes verus. Compared to the human genetic map, broad-scale recombination rates tend to be conserved, but with exceptions, particularly in regions of chromosomal rearrangements and around the site of ancestral fusion in human chromosome 2. At fine scales, chimpanzee recombination is dominated by hotspots, which show no overlap with those of humans even though rates are similarly elevated around CpG islands and decreased within genes. The hotspot-specifying protein PRDM9 shows extensive variation among Western chimpanzees, and there is little evidence that any sequence motifs are enriched in hotspots. The contrasting locations of hotspots provide a natural experiment, which demonstrates the impact of recombination on base composition. 相似文献
113.
Sokolow SH Rand C Marks SL Drazenovich NL Kather EJ Foley JE 《American journal of veterinary research》2005,66(6):1018-1024
OBJECTIVES: To determine associations among infectious pathogens and diarrheal disease in dogs in an animal shelter and demonstrate the use of geographic information systems (GISs) for tracking spatial distributions of diarrheal disease within shelters. SAMPLE POPULATION: Feces from 120 dogs. PROCEDURE: Fresh fecal specimens were screened for bacteria and bacterial toxins via bacteriologic culture and ELISA, parvovirus via ELISA, canine coronavirus via nested polymerase chain reaction assay, protozoal cysts and oocysts via a direct fluorescent antibody technique, and parasite ova and larvae via microscopic examination of direct wet mounts and zinc sulfate centrifugation flotation. RESULTS: Salmonella enterica and Brachyspira spp were not common, whereas other pathogens such as canine coronavirus and Helicobacter spp were common among the dogs that were surveyed. Only intestinal parasites and Campylobacterjejuni infection were significant risk factors for diarrhea by univariate odds ratio analysis. Giardia lamblia was significantly underestimated by fecal flotation, compared with a direct fluorescent antibody technique. Spatial analysis of case specimens by use of GIS indicated that diarrhea was widespread throughout the entire shelter, and spatial statistical analysis revealed no evidence of spatial clustering of case specimens. CONCLUSIONS AND CLINICAL RELEVANCE: This study provided an epidemiologic overview of diarrhea and interacting diarrhea-associated pathogens in a densely housed, highly predisposed shelter population of dogs. Several of the approaches used in this study, such as use of a spatial representation of case specimens and considering multiple etiologies simultaneously, were novel and illustrate an integrated approach to epidemiologic investigations in shelter populations. 相似文献
114.
115.
A simplified method for monitoring eggs of the grape leafhopper (Empoasca vitis) in grapevine leaves
Journal of Plant Diseases and Protection - Based on a previously reported method for monitoring eggs of the grape leafhopper (Böll and Herrmann 2001) stated as Leda (Leafhopper Egg Detection... 相似文献
116.
Transabdominal ultrasonography was performed to visualize the development of intraocular structures of both eyes of four different fetuses in each of two pregnant beagles. Postnatally the development of both eyes of 11 pups was visualized with ultrasonography. Furthermore, biometric measurements of the length of the eye, the depth of cornea, the anterior chamber, the lens (anteroposterior depth and equatorial diameter), and the vitreous body of the fetuses and pups were obtained when these structures could be identified with ultrasonography. In all fetuses the eyes with lens, vitreous body, hyaloid artery, and scleroretinal rim could be clearly identified from day 37 of pregnancy. Postnatally also the cornea, anterior chamber, iris, ciliary body, and optic disc were visible. Biometric measurements revealed, both pre- and postnatally, a continuous growth of the depth of the eye, anterior chamber, lens (anteroposterior depth and equatorial diameter), and vitreous body. 相似文献
117.
Edyta Halupecki Carlo Bazzi Susanne Jock Klaus Geider Damir Đermić Bogdan Cvjetković 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):435-440
Erwinia amylovora is the causative agent of fire blight, a destructive disease of rosaceous plants. The European population can be divided
into several subtypes according to differences in restriction fragment length polymorphism of the XbaI genomic DNA digest analysed with pulsed-field gel electrophoresis. This technique was also used to determine the genetic
relatedness of six Croatian isolates to the E. amylovora types found in the countries surrounding Croatia. The isolates belong to the Pt2 pattern type that is characteristic of the
East Mediterranean basin. All tested isolates gave essentially the same total cell protein pattern in SDS-polyacrylamide gel
electrophoresis. The number of short-sequence DNA repeats in plasmid pEA29 of six isolates was determined by PCR assays and
ranged from four to seven. The isolates examined showed high pathogenicity in immature pear fruits. Differences were also
revealed in microbiological assays such as amylovoran synthesis, levan formation, siderophore production and colour on coliform
medium. 相似文献
118.
Kloss S Wehrend A Failing K Bostedt H 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(7-8):247-251
The incidence of dystocia from ewes in nine lambing periods (1992-2000) was recorded at an obstetrical clinic. First we analysed parturition difficulties in normal pregnant sheep (group 1, n = 229). In the second group parturitions of ewes with vaginal prolapse ante partum were investigated (n = 129). In group 1 maternal causes of dystocia occurred more often than fetal ones (50% maternal, 45% fetal). In maternal parturition difficulties ringwomb was the dominating reason (64%), while abnormal presentations, position and/or posture of the lambs occurred most frequently in fetal dystocia (67%). But there was no statistical influence of age and number of parturitions in both groups. The average of the first notice of prolapsed vaginal tissue was 11 days before lambing. There was a predominance in the affection of sheep at first and second pregnancy (52%). Only 26% of the group 2 sheep had a spontaneous delivery. In 58% of the cases a dystocia was diagnosed. A preterm caesarean section had carried out in 12%, five ewes died before parturition because of septicemia (4%). Sheep suffering from vaginal prolapse ante partum showed maternal caused dystocia significant more frequently than members of group 1 (p < 0.001), with ringwomb as dominating reason (70%). The number of born lambs was significant higher in group 2 than in group 1 (p = 0.019). 相似文献
119.
Rabsch W Mirold S Hardt WD Tschäpe H 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(9-10):355-359
Salmonella bacteriophages seem to mediate horizontal transfer of virulence functions among Salmonella strains in two different ways: by general transduction and also by lysogenic conversion. The majority of wild phages isolated from Salmonella strains belong to the P22 like phages and were able to transduce. Our data show that the lysogenic conversion is generally accompanied by changes in the susceptibility to the typing phages used for epidemiological purposes. Similar phage type conversions to S. Typhimurium DT104 could be detected upon lysogenization with two other S. Typhimurium strains. For some S. Typhimurium strains the typical phage pattern is actually associated with alterations of virulence characteristics. For example, all tested wild type isolates of phage types DT49 and DT204 were found to be SopE phi-lysogens. The Anderson typing phages interfere with the prophages and/or cryptic phages and so the complex genetic short-term evolution can be demonstrated in the lab. This is one reason for the successful application of phage typing in Salmonella epidemiology since the 50s. 相似文献
120.
Radiolabeled methyl farnesoate is epoxidized to juvenile hormone III by an NADPH-dependent reaction occurring in corpus allatum homogenates from the cockroach Blaberus giganteus L. Most of the enzymatically produced juvenile hormone has the 10R configuration described for previously isolated natural juvenile hormones. The unnatural 2Z geometrical isomer of methyl farnesoate is epoxidized by the above system faster than the natural 2E isomer. Several series of chemicals known to be inhibitors of mixed-function oxidases were surveyed as inhibitors of methyl farnesoate epoxidation. The anti-juvenile hormone precocene II caused negligible inhibition at 1 · 10?4M, whereas the best inhibitor was o-bromophenoxymethyl-imidazole with an apparent I50 of 4 · 10?7M. None of the inhibitors tested were potent morphogenetic agents on Tenebrio molitor pupae, and they failed to cause precocious development of Oncopeltus fasciatus nymphs. The inhibition of in vitro juvenile hormone biosynthesis suggests the possibility of finding an anti-hormone which acts by blocking juvenile hormone biosynthesis. 相似文献