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241.
The prevalence of Toxocara cati in domestic cats in Mexico City   总被引:2,自引:0,他引:2  
The faeces of 520 domestic cats, resident in the 16 municipal authorities of Mexico City, were analysed using the method of centrifuging with zinc sulphate (at 33%). Three hundred and ninety-nine animals lived in houses, 121 in apartments. For the purpose of this study they were divided into seven age groups, of 6 months each. Toxocara cati eggs were found in the faeces of 42.5% of the animals. 20.7% of apartment cats and 49.1% of house cats were infected. This difference in the rate of infection is statistically significant (P<0.002.) for the house cats. T. cati was found in all the age groups although most infection was found in animals less than 1 year old.The fact that infection occurred in the whole age range of the cats and in all the municipal authorities means that the risk of being contaminated with this helminth in Mexico City is high. As a consequence, the possibility of developing illness as a result of becoming a host to larva migrans is also high.  相似文献   
242.
This study describes attempts to increase and measure sensitivity of molecular tests to detect avian pneumovirus (APV). Polymerase chain reaction (PCR) diagnostic tests were designed for the detection of nucleic acid from an A-type APV genome. The objective was selection of PCR oligonucleotide combinations, which would provide the greatest test sensitivity and thereby enable optimal detection when used for later testing of field materials. Relative and absolute test sensitivities could be determined because of laboratory access to known quantities of purified full-length DNA copies of APV genome derived from the same A-type virus. Four new nested PCR tests were designed in the fusion (F) protein (2 tests), small hydrophobic (SH) protein (1 test), and nucleocapsid (N) protein (1 test) genes and compared with an established test in the attachment (G) protein gene. Known amounts of full-length APV genome were serially diluted 10-fold, and these dilutions were used as templates for the different tests. Sensitivities were found to differ between the tests, the most sensitive being the established G test, which proved able to detect 6,000 copies of the G gene. The G test contained predominantly pyrimidine residues at its 3' termini, and because of this, oligonucleotides for the most sensitive F test were modified to incorporate the same residue types at their 3' termini. This was found to increase sensitivity, so that after full 3' pyrimidine substitutions, the F test became able to detect 600 copies of the F gene.  相似文献   
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A 5 years old female ferret with an abdominal palpable mass confirmed at echo-graphic examination died during an explorative laparotomy. A single lymph-node-like nodule was found adjacent to the intestinal loops. The round mass well circumscribed, solid and white, histologically, at low magnification, appeared encapsulated and built up by a population of atypical spindle cells arranged in interwoven fascicles. The cells had high anisocytosis degree, moderate mitotic activity and prominent nucleoli. A central area of necrosis was present. To characterise the tumour immunohistochemically cytokeratin, vimentin, S-100, melan-A, vWF, desmin, actin and alpha-actin were applied. Neoplastic cells resulted positive to vimentin, actin and alpha-actin. Based on the histological and immunohistological pattern a diagnosis of leiomyosarcoma was made.  相似文献   
245.
Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter® and Corneometer® measurements indicated that Ech A treatment reduced transepidermal water loss and improved stratum corneum hydration, respectively. Ech A treatment also inhibited inflammatory-response-induced mast cell infiltration in AD-like skin lesions and suppressed the expression of proinflammatory cytokines, such as interferon-γ, interleukin-4, and interleukin-13. Collectively, these results suggest that Ech A may be beneficial for treating AD owing to its anti-inflammatory effects.  相似文献   
246.
Posidonia oceanica (L.) Delile is traditionally used for its beneficial properties. Recently, promising antioxidant and anti-inflammatory biological properties emerged through studying the in vitro activity of the ethanolic leaves extract (POE). The present study aims to investigate the anti-inflammatory and analgesic role of POE in mice. Inflammatory pain was modeled in CD-1 mice by the intraplantar injection of carrageenan, interleukin IL-1β and formalin. Pain threshold was measured by von Frey and paw pressure tests. Nociceptive pain was studied by the hot-plate test. POE (10–100 mg kg−1) was administered per os. The paw soft tissue of carrageenan-treated animals was analyzed to measure anti-inflammatory and antioxidant effects. POE exerted a dose-dependent, acute anti-inflammatory effect able to counteract carrageenan-induced pain and paw oedema. Similar anti-hyperalgesic and anti-allodynic results were obtained when inflammation was induced by IL-1β. In the formalin test, the pre-treatment with POE significantly reduced the nocifensive behavior. Moreover, POE was able to evoke an analgesic effect in naïve animals. Ex vivo, POE reduced the myeloperoxidase activity as well as TNF-α and IL-1β levels; further antioxidant properties were highlighted as a reduction in NO concentration. POE is the candidate for a new valid strategy against inflammation and pain.  相似文献   
247.
248.
Tomato black ring virus (TBRV) is a worldwide-distributed RNA virus infecting a wide range of different host plants, including crop species, trees, shrubs, and weeds. Here, we investigated the molecular evolution of TBRV and its adaptability to different plant species. The TBRV-Pi isolate was used to generate five independent evolution lineages serially passaged in either quinoa, tobacco, or tomato plants. After 15 passages, the genetic variability present in all the lineages was characterized for the movement (MP) and coat (CP) coding cistrons. We addressed two main questions: to what extent does the amount of genetic variability in the TBRV genome depend on the host species, and are there host species-specific adaptive mutations? Overall, 201 different nucleotide substitutions emerged during the evolution experiment, with some of them appearing multiple times in different lineages; two of them (one in CP and one in MP) were unique for a particular host plant. We have shown that the degree of genetic differentiation depends on the host species in which the virus evolved, and that positive selection is operating upon certain residues, particularly in CP. Moreover, we have characterized new types of defective RNAs that arose during the TBRV-Pi evolution in tobacco. Furthermore, this is the first report of a defective RNA from the RNA2 of TBRV.  相似文献   
249.
250.
Using the approach of sequencing the V3-V4 region of the 16S rRNA gene, we have analysed the bacterial diversity associated with the distinct compartments of the gastrointestinal tract of perch (Perca fluviatilis) and cestodes (Proteocephalus sp.) parasitizing their digestive tract. The dominant microbiota associated with cestodes (Proteocephalus sp.) was represented by bacteria from the genera Serratia, Pseudomonas and Mycoplasma. By comparing the associated microbiota of perch and cestodes, a clear difference in bacterial composition and diversity was revealed between the community from the stomach content and other parts of the gastrointestinal tract of fish. Microbiota associated with cestodes was not significantly different in comparison with microbiota of different subcompartments of perch (mucosa and content of intestine and pyloric caeca) (ADONIS, p > .05) excluding microbiota of stomach content (ADONIS, p ≤ .05). PICRUSt-based functional assessments of the microbial communities of perch and cestodes indicated that they mainly linked in terms of metabolism and environmental information processing and could play an important role in the nutrition and health of host.  相似文献   
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