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排序方式: 共有1580条查询结果,搜索用时 15 毫秒
1.
Edwin H. Robinson Menghe H. Li Bruce B. Manning 《Journal of the World Aquaculture Society》2001,32(1):68-71
Abstract.— This study was conducted to evaluate corn gluten feed as an alternative feedstuff in the diet of pond-raised channel catfish Ictalurus punctatus . Three 32%-protein diets containing 0%, 25%, or 50% corn gluten feed were tested. Channel catfish fingerlings (average weight: 57 g/fish) were stocked into 15 0.04-ha ponds at a rate of 18,530 fish/ha. Five ponds were used for each dietary treatment. Fish were fed to satiation once daily for a 147-d growing period. No differences were observed in feed consumption, weight gain, feed conversion ratio, survival, or fillet protein concentration among fish fed the test diets. Fish fed diets containing 25% and 50% corn gluten feed exhibited a lower level of visceral fat and a higher carcass yield than fish fed the control diet without corn gluten feed. The diet containing 50% corn gluten feed resulted in a lower level of fillet fat and a higher level of moisture than the control diet. There were no visible differences in the coloration of skin or fillet of channel catfish fed diets with and without corn gluten feed. Results from this study indicated that channel catfish can efficiently utilize corn gluten feed at levels up to 50%n without adverse effect on feed palatability, weight gain, or feed efficiency. Corn gluten feed may be beneficial in reducing fattiness of channel catfish and improving carcass yield by reducing the digestible energy to protein ratio of the diet. 相似文献
2.
Olson ME Bruce J 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(12):523-527
This article describes the surgical procedures for the ovariectomy, ovariohysterectomy and orchidectomy in rodents and rabbits. The indications for each procedure are outlined and effective and safe anesthetics are described. Preoperative and postoperative care is also discussed. 相似文献
3.
Twenty-seven compounds were screened as potential inhibitors of juvenile hormone esterases. Of these compounds O-ethyl-S-phenyl phosphoramidothiolate provided the best inhibition for the cabbage looper, Trichoplusia ni (Hubner), and the yellow mealworm, Tenebrio molitor L., while the juvenile hormone esterases of the house fly, Musca domestica L., were best inhibited by a juvenoid carbamate (1-(m-phenoxy-N-ethyl carbamate)-3,7-dimethyl-7-methoxy-2E-octene). The inhibition patterns of T. ni and T. molitor are similar, while those of M. domestica are relatively different. Further studies on the juvenile hormone and α-napthyl acetate esterases of T. ni showed that they could be differentially inhibited. Diisopropyl phosphorofluoridate and an alkyl trifluoromethyl ketone selectively inhibit the hydrolysis of α-naphthyl acetate and juvenile hormone, respectively, while O-ethyl-S-phenyl phosporamidothiolate inhibits both enzymes. The juvenile hormone esterases of T. ni also appear to be unique enzymes that are selective for juvenile-hormone-like molecules. The in vivo inhibition of T. ni juvenile hormone esterases by O-ethyl-S-phenyl phosphoramidothiolate slows the in vivo hydrolysis of juvenile hormone and results in delayed pupation and malformed larvae that resemble larval-pupal intermediates. Thus, the esterases involved in juvenile hormone metabolism appear to be important in juvenile hormone regulation. 相似文献
4.
C. Jacyn Baker Daniel P. Roberts Norton M. Mock Bruce D. Whitaker Kenneth L. Deahl Andrey A. Averyanov 《Physiological and Molecular Plant Pathology》2005,67(6):1322
The plant apoplast is an important mediator of communication between the cell cytoplasm and its surroundings. Plant cell suspensions offer a convenient model system to gain insight into apoplastic physiology. Here, we describe a novel phenomenon that took place when two naturally occurring phenolics were added together to either soybean or tobacco cell suspensions. Acetosyringone (AS) and/or hydroxyacetophenone (HAP), phenolics found in the extracellular/apoplast of tobacco cells, were added to soybean or tobacco cell suspensions undergoing an oxidative burst. Individually, AS appeared to be utilized as a typical peroxidase substrate to scavenge hydrogen peroxide, while HAP was utilized at a much lower rate. However, when added together the rate of utilization of both phenolics increased and surprisingly resulted in the production of hydrogen peroxide. We have further characterized this novel phenomenon in suspension cells. This study demonstrates that certain phenolics in plants can cause co-oxidation which, as in animals, could alter the structure and bioactivity of surrounding phenolics. 相似文献
5.
Clovis S. Palmer Jennifer A. Saleeba Bruce R. Lyon 《Physiological and Molecular Plant Pathology》2005,67(6):427
A phytotoxic protein that evokes the typical symptoms of Verticillium wilt disease in seedlings of Gossypium hirsutum L. (Upland cotton) was isolated from culture filtrates of Verticillium dahliae. The protein was purified by ammonium sulfate precipitation, Sephadex-G100 fractionation, and native PAGE. The 18.5 kDa protein, designated VD18.5, appears to be a single subunit protein with an isoelectric point between 3 and 5. VD18.5 induces symptoms of leaf dehydration, chlorosis, necrosis and stem discoloration in seedlings of the disease susceptible cotton cultivar Siokra 1–4. The LD50 of VD18.5 on protoplasts of Siokra 1–4 was 18 μg mL−1. VD18.5 had no noticeable effect on Pima S-7, which is a disease resistant cultivar. Phytotoxic activity was partially destroyed at high temperature and was abolished by digestion with proteinase K. Mass spectrometry fingerprinting and protein sequence data from VD18.5 yielded no significant matches when submitted to the Mascot search engine and NCBI non-redundant protein databases, respectively. These results suggest that VD18.5 is a novel protein that may be involved in the development of some of the symptoms associated with Verticillium wilt disease in the cotton plant. 相似文献
6.
7.
Kyoung-Jin Yoon Bruce H Janke Rick W Swalla Gene Erickson 《Journal of veterinary diagnostic investigation》2004,16(3):197-201
Recently a commercial enzyme-linked immunosorbent assay (ELISA) kit for detecting antibody against H1N1 swine influenza virus (SIV) has been made available to diagnosticians and veterinary practitioners. Because the hemagglutination inhibition (HI) test has been considered the standard test for SIV serology, diagnostic performance of the new ELISA was evaluated using positive (n = 60) and negative (n = 188) serum samples from young pigs with known status of SIV infection and compared with that of the HI test. Both ELISA and HI test identified all negative animals correctly. None of the serum samples (n = 64) from pigs inoculated with H3N2 SIV was positive by ELISA for SIV antibody. The H1N1 SIV antibody detectable by ELISA appears to develop more slowly in comparison with antibody detectable by HI test. Although antibody was detected by HI test in all inoculated animals (n = 20) by day 7 postinoculation (PI), antibody was detected by ELISA in 0%, 75%, and 100% of the inoculated animals on days 7, 14, and 28 PI, respectively. Discrepancy in test results between the 2 serologic tests appeared to be because of differences in antibody isotypes detected by each test. Enzyme-linked immunosorbent assay mainly detected IgG antibody, whereas the HI test detects IgM antibody very efficiently as well as IgG antibody. Collectively, the commercial ELISA is highly specific for antibody to H1N1 SIV but may not identify positive animals at the early stage of infection as effectively as the HI test, particularly when SIV is introduced to a na?ve swine population. 相似文献
8.
9.
Computed Tomographic Angiography of the Pancreas in Cats with Chronic Diabetes Mellitus Compared to Normal Cats 下载免费PDF全文
S. Secrest A. Sharma A. Bugbee 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(3):962-966
Background
Diabetes mellitus (DM) is a common endocrinopathy in cats. No known diagnostic test or patient characteristic at the time of diagnosis can predict likely disease course, unlike in people in whom computed tomographic angiography (CTA) is used. No published data exist regarding the CTA appearance of the pancreas in cats with DM, and thus, it is unknown what if any CTA variables should be further assessed for associations with pancreatic endocrine function.Hypothesis/Objectives
A significant difference in pancreatic attenuation, volume, and size will be identified between normal cats and those with chronic DM on CTA.Animals
Ten healthy control cats and 15 cats with naturally occurring DM present for >12 months.Methods
Prospective cross‐sectional study comparing pancreatic attenuation, enhancement pattern, size, volume, pancreatic volume‐to‐body weight ratio (V:BW), pancreatic arterial: portal phase ratio (A:P), time‐to‐arterial enhancement, and time‐to‐peak portal enhancement on CTA between sedated healthy control cats and those with chronic DM.Results
The pancreas in cats with chronic DM was significantly larger, had higher volume, higher V:BW, and shorter time‐to‐peak portal enhancement on CTA when compared to normal cats.Conclusions and Clinical Importance
Peak portal enhancement time, pancreatic size, pancreatic volume, and V:BW can be used to differentiate normal sedated cats from those with chronic DM by CTA. These variables warrant further investigation to identify possible associations with endocrine function. 相似文献10.