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381.
Gametophytic selection has potential to increase the efficiency of breeding for temperature tolerance. Here, we describe orchid seedlings after application of low and high temperatures during gametophytic development. In addition to phenotypic traits, amplified fragment length polymorphism (AFLP) markers were used to determine the genetic variability in seedlings. Two hybrid Phalaenopsis were cross-pollinated and exposed to 30°C day/25°C night for 3 days for a warm pollination or 15°C day/10°C night for 7 days as a cold pollination treatment. The plants were returned to the greenhouse after pollination and green capsules were collected after 150 days. Protocorms obtained from these treatments were evaluated 72 days after initial plating for germination and size on a thermogradient table ranging from 10 to 30°C. Seedlings were then evaluated 1 year after initial plating. The mean number of roots per seedling (4.2) was greater for plantlets that derived from the cold pollination treatment compared to those from warm pollination (3.6). Weight of the seedlings, number of roots and the average root length were significantly affected by the interaction between pollination treatment and germination temperature. The weight, number of leaves, and average root length were significantly affected by the interaction between pollination treatment and incubator/growth chamber. The results indicated that seedlings derived from warm pollination were more vigorous under warm growing conditions and those derived from cold pollination were more vigorous under cold growing conditions. Genetic variation among 16 F1 seedlings randomly selected from various temperature treatments was analyzed. A dendrogram based on 651 loci resulted in three major groups and one subgroup. The groups and subgroup revealed common selection pressure during the gametophytic stage. The AFLP data support genetic differentiation of Phalaenopsis hybrids pollinated under different temperatures.  相似文献   
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Objective To evaluate the efficacy and tolerance of a treatment protocol for anxiety-related and obsessive-compulsive disorders in cats.
Design A study was undertaken to assess the clinical response in cats diagnosed with anxiety-related or obsessive-compulsive disorders to a treatment regimen that included clomipramine and behaviour modification.
Procedure The study group of 11 cats was acquired through referral. A detailed behavioural and clinical history was obtained. Presenting signs were urine spraying in seven cases, overgrooming in three and excessive vocalisation in one. Clomipramine was administered orally once daily. The mean starting dose was 0.4 mg/kg. If necessary, the dose was adjusted according to the clinical response of each cat. A behaviour modification program was designed and the owner instructed on its implementation. Cats were to continue on medication for at least 1 month after clinical signs disappeared, then medication withdrawal was to be attempted by decreasing the clomipramine dose progressively at weekly intervals while the behaviour modification program continued.
Results In all cases the presenting clinical sign was largely improved or disappeared. One cat was removed from the study by the owner. Four cats became lethargic at higher doses, but this resolved when the clomipramine dose was reduced. The average maintenance dosage was 0.3 mg/kg once daily. Clomipramine withdrawal was attempted in two cases: the behaviour returned in one case and the medication was reinstated at 0.3 mg/kg twice daily.
Conclusion Clomipramine was effective in controlling the signs of anxiety-related and obsessive-compulsive disorders in 10 of 10 assessable cases when used in combination with behaviour modification. Clomipramine was well tolerated.  相似文献   
384.
Widespread iron limitation of phytoplankton in the south pacific ocean   总被引:1,自引:0,他引:1  
Diel fluorescence patterns were discovered in phytoplankton sampled over 7000 kilometers of the South Pacific Ocean that appear indicative of iron-limiting growth conditions. These patterns were rapidly lost after in situ iron enrichment and were not observed during a 15,000-kilometer transect in the Atlantic Ocean where iron concentrations are relatively high. Laboratory studies of marine Synechococcus sp. indicated that the patterns in the South Pacific are a unique manifestation of iron limitation on the fluorescence signature of state transitions. Results suggest that primary productivity is iron limited not only throughout the equatorial Pacific but also over much of the vast South Pacific gyre.  相似文献   
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The prevalence of Trypanosoma evansi was investigated in 1,250 Nili-Ravi buffaloes of mixed age and sex by polymerase chain reaction (PCR) for the first time in Pakistan. DNA of the trypanosomes was isolated with TRIREAGENT®. The assay was employed using primers ESAG 6/7, specific for a 237-bp fragment from T. evansi genomic DNA. The samples were screened for the presence of T. evansi also by stained thin smear. Forty-four (3.5%) samples were positive by microscopy, while 97 (7.7%) samples were identified by PCR, indicating the high sensitivity of PCR for surveying the disease in epidemiological studies.  相似文献   
387.
Expression of the protein DDX4/MVH, or VASA, has been reported in germ cells of several species. The main objectives of this study were to (i) investigate VASA expression patterns in testicular cells of stallions at two different reproductive stages (pre‐pubertal and post‐pubertal) and (ii) evaluate the use of VASA antibody as a molecular marker for single germ cells from stallions. Testicular tissues were obtained from stallions and categorized as pre‐pubertal and post‐pubertal based on the formation of lumen and status of spermatogenesis on the cross section of seminiferous tubules. The results of Western blot showed a VASA protein band located at 76 kDa, indicating that the rabbit antibody has a cross‐reactivity with horse testicular tissues. The result of immunolabelling showed that VASA was expressed in the cytoplasm of spermatogonia at both reproductive stages and in spermatocytes and round spermatids at the post‐pubertal stage. GATA4‐positive Sertoli cells and Leydig cells located in the interstitial space were not immunolabelled with VASA. These results suggest that VASA can be utilized as a molecular marker for germ cells of stallions at pre‐pubertal and post‐pubertal stages. Interestingly, immunolabelling intensity was significantly higher in pachytene spermatocytes compared to spermatogonia and round spermatid. VASA antibody was also effective for staining of single germ cell preparations. In conclusion, VASA protein expression can be used as a marker for identification of spermatogonia, spermatocytes and round spermatids in testicular tissues of stallions.  相似文献   
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389.
This paper reports a presumptive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a cat. A cat with respiratory disease living with three individuals with coronavirus disease 2019 showed bilateral ground-glass opacities in the lung on X-ray and computed tomography. The clinical swabs were negative for SARS-CoV-2 RNA, but the serum was positive for SARS-CoV-2 antibodies. Interstitial pneumonia and prominent type 2 pneumocyte hyperplasia were noted on histopathology. Respiratory tissues were negative for SARS-CoV-2 RNA or antigen, but the cat was positive for feline parvovirus DNA. In conclusion, the respiratory disease and associated pathology in this cat could have been due to exposure to SARS-CoV-2.  相似文献   
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