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排序方式: 共有167条查询结果,搜索用时 15 毫秒
71.
Booth NL Overk CR Yao P Totura S Deng Y Hedayat AS Bolton JL Pauli GF Farnsworth NR 《Journal of agricultural and food chemistry》2006,54(4):1277-1282
Red clover (Trifolium pratense L., Fabaceae) dietary supplements are currently used to treat menopausal symptoms because of their high content of the mildly estrogenic isoflavones daidzein, genistein, formononetin, and biochanin A. These compounds are estrogenic in vitro and in vivo, but little information exists on the best time to harvest red clover fields to maximize content of the isoflavones and thus make an optimal product. Samples of cultivated red clover above-ground parts and flower heads were collected in parallel over one growing season in northeastern Illinois. Generally, autohydrolytic extracts of above-ground parts contained more isoflavones and had more estrogenic activity in Ishikawa endometrial cells as compared with extracts of flower heads. Daidzein and genistein contents peaked around June to July, while formononetin and biochanin A contents peaked in early September. Flower head and total above-ground parts extracts exhibited differential estrogenic activity in an Ishikawa (endometrial) cell-based alkaline phosphatase induction assay, whereas nondifferential activity was observed for most extracts tested in an MCF-7 (breast) cell proliferation assay when tested at the same final concentrations. Ishikawa assay results could be mapped onto the extracts' content of individual isoflavones, but MCF-7 results did not show such a pattern. These results suggest that significant metabolism of isoflavones may occur in MCF-7 cells but not in Ishikawa cells; therefore, caution is advised in the choice of bioassay used for the biological standardization of botanical dietary supplements. 相似文献
72.
OBJECTIVE: To evaluate the effectiveness of preoperative administration of oral carprofen, subcutaneous ketoprofen, and local nerve block with bupivacaine in preventing postoperative pain-associated behavior in cats after ovariohysterectomy. ANIMALS: Fifty-two female intact cats. Materials and methods Cats received butorphanol (0.44 mg kg(-1) IM), carprofen (2.2 mg kg(-1) PO), ketoprofen (2.2 mg kg(-1) SQ), or bupivacaine infiltration block (1.1 mg kg(-1) SQ) before surgery. Cortisol and drug concentrations and visual analog scale (VAS) and interactive visual analog scale (IVAS) pain-associated behavior scores were measured 2 hours before and 0, 1, 2, 4, 8, 12, and 24 hours after ovariohysterectomy. RESULTS: Cats receiving butorphanol had significantly increased IVAS scores 2 hours after surgery compared with baseline measurements. Cats receiving carprofen, ketoprofen, and bupivacaine had significant increases from baseline in VAS and IVAS scores 1 and 2 hours after surgery. VAS and IVAS scores for cats receiving bupivacaine were significantly greater 1 and 2 hours after surgery than for cats that received butorphanol. Cats receiving carprofen had significant increases in cortisol 1 hour after surgery and significant decreases 24 hours after surgery compared with baseline measurements. CONCLUSIONS AND CLINICAL RELEVANCE: Preoperative carprofen and ketoprofen have effects on pain-associated behavior similar to butorphanol in cats undergoing ovariohysterectomy. Cats receiving bupivacaine blocks may require additional analgesics immediately after surgery. 相似文献
73.
A practical method for almond cultivar identification and parental analysis using simple sequence repeat markers 总被引:3,自引:0,他引:3
Early and accurate identification of almond [Prunus dulcis (Mill.) D.A. Webb] cultivars is critical to commercial growers and nurseries. Previously published simple sequence repeat
loci were examined for their ability to distinguish commonly grown almond cultivars. Twelve highly polymorphic loci were selected
for their ability to uniquely identify a set of 18 almond cultivars commonly grown in California, many of which are closely
related. These markers also allow an accurate assessment of parent/progeny relationships among cultivars. This system can
reliably identify at an early stage of development all major California almond cultivars in current production. 相似文献
74.
Fast‐to‐slow shift of muscle fiber‐type composition by dietary apple polyphenols in rats: Impact of the low‐dose supplementation
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Wataru Mizunoya Shinpei Okamoto Hideo Miyahara Mariko Akahoshi Takahiro Suzuki Mai‐Khoi Q. Do Hideaki Ohtsubo Yusuke Komiya Mulan Qahar Toshiaki Waga Koichi Nakazato Yoshihide Ikeuchi Judy E. Anderson Ryuichi Tatsumi 《Animal Science Journal》2017,88(3):489-499
Our previous studies demonstrated that an 8‐week intake of 5% (w/w) apple polyphenol (APP) in the diet improves muscle endurance of young‐adult rats. In order to identify a lower limit of the dietary contribution of APP to the effect, the experiments were designed for lower‐dose supplementation (8‐week feeding of 0.5% APP in AIN‐93G diet) to 12‐week‐old male Sprague‐Dawley rats. Results clearly showed that the 0.5% APP diet significantly up‐regulates slower myosin‐heavy‐chain (MyHC) isoform ratios (IIx and IIa relative to total MyHC) and myoglobin expression in lower hind‐limb muscles examined (P < 0.05). There was a trend to increased fatigue resistance detected from measurements of relative isometric plantar‐flexion force torque generated by a stimulus train delivered to the tibial nerve (F(98, 1372) = 1.246, P = 0.0574). Importantly, there was no significant difference in the animal body‐phenotypes or locomotor activity shown as total moving distance in light and dark periods. Therefore, the present study encourages the notion that even low APP‐intake may increase the proportions of fatigue‐resistant myofibers, and has promise as a strategy for modifying performance in human sports and improving function in age‐related muscle atrophy. 相似文献
75.
76.
Jennie L. Pearce David Anthony Kirk Cynthia P. Lane Marguerite H. Mahr John Walmsley Daniel Casey Judy E. Muir Susan Hannon Andrew Hansen Kingsford Jones 《Biological conservation》2008,141(4):908-924
Prioritizing new areas for conservation in the Rocky Mountains of North America is important because the current intensity and scale of human development poses an immediate threat to biodiversity. We identified priority areas for avian biodiversity within a 3200-km corridor from Yellowstone National Park in Wyoming, US to the Yukon in Canada (the Y2Y region). We applied the conservation planning tool, MARXAN, to summarize 21 avian values. MARXAN minimizes the area delineated, while simultaneously incorporating multiple criteria (species richness representation, spatial clustering) and biodiversity targets into a single mappable solution. We prioritized avian biodiversity ‘hotspots’ at continental and ecoprovincial scales based on: (1) avian species richness; and (2) habitat associations of 20 focal species. At the continental scale, the single best solution represented 19% of the Y2Y region; 29% of this solution overlapped with existing protected areas. In northern Y2Y, large contiguous areas with high avian value were concentrated on the western edge of the continental divide. In southern Y2Y, contiguous areas were smaller and more numerous than in the north. In contrast to the majority of studies prioritizing conservation areas, we explored the effect of varying the extent of the target region by analyzing data at the scale of the entire Y2Y region and for eight ecoprovinces separately. We found that (1) large contiguous patches characterized only three ecoprovinces, while for the remaining ecoprovinces, numerous single scattered habitat patches of varying sizes were required to meet conservation goals; and (2) generally, only a small percentage of sites was already protected within the existing protected areas network. Our results are important for conservation planners and resource managers in the Y2Y region for incorporating areas of high conservation value for birds at regional and ecoprovincial scales during conservation project design and adaptive planning. 相似文献
77.
THE ISOLATION OF MYCOPLASMAS FROM CATS WITH RESPIRATORY DISEASE 总被引:1,自引:0,他引:1
P. B. Spradbrow B.V.Sc. Ph.D. Judy Marley B.Sc. B. Portas G. Burgesss 《Australian veterinary journal》1970,46(3):109-110
Mycoplasma were isolated from 11 of 160 samples from cats with respiratory disease. Most isolations were made from nasal swabs. Two of the isolates were tested for metabolic activity, and one fermented glucose while the other metabolized arginine. Metabolism-inhibiting antibodies active against the arginine metabolizing mycoplasmas were present in 6 of 20 cats serums at titres of from 1/2 to 1/8. Antibodies against the glucose fermenting mycoplasma were not present in any of the 20 serums. 相似文献
78.
ABSTRACT Previously, we demonstrated that Broad bean mottle virus (BBMV), a member of the genus Bromovirus, could accumulate RNA 2-derived defective interfering (DI) RNAs during infection. In this work, we study how host and environmental factors affect the accumulation of DI RNAs. Serial passages of BBMV through selected plant species reveal that, with low-multiplicity inocula, some systemic hosts (Vicia faba, Nicotiana clevelandii, and N. tabacum cv. Samsum) support DI RNA accumulation after the first passage cycle but other hosts (Phaseolus vulgaris, Pisum sativum, and Glycine max) do not. However, several passages with the high-multiplicity inocula can generate DI RNAs in pea plants. Local lesion hosts (Chenopodium quinoa, C. amaranticolor, and C. murale) remain free of the DI RNA components. The size of the de novo-formed DI RNAs depends on the host and on environmental conditions. For instance, broad bean plants cultivated in a greenhouse or in a growth chamber at 20 degrees C accumulated DI RNAs of 2.4 or 1.9 kb in size, respectively. A reverse trend was observed in pea plants. Lower temperatures greatly facilitated the formation of DI RNAs in broad bean and pea hosts after the first passage. The importance of these findings for the studies on DI RNAs are discussed. 相似文献
79.
Keller RL Avery AC Burnett RC Walton JA Olver CS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(3):145-149
BACKGROUND: Uniquely rearranged immunoglobulin and T-cell receptor gene sequences can be amplified and electrophoretically separated by size to detect a clonal population of lymphocytes. OBJECTIVE: The purpose of this study was to determine whether the polymerase chain reaction (PCR) detects neoplastic (clonal) lymphocytes more frequently than do microscopic methods. METHODS: We identified neoplastic lymphocytes in peripheral blood by both routine and standardized microscopic examination of blood smears and by PCR amplification of blood-derived DNA and compared the 3 methods for frequency of detection of leukemic involvement. For standardized microscopic examination (200 leukocytes counted on Wright-Giemsa-stained blood smears), samples were categorized as negative (=1% prolymphocytes), equivocal (>1% prolymphocytes, no lymphoblasts), or positive (>/=1 lymphoblast). A PCR-amplified sample was positive if 1 or 2 discrete bands were seen on the gel, or negative if no bands, a smear, or a faint ladder was seen. RESULTS: Using PCR, neoplastic lymphocytes were detected in peripheral blood 2.5 times more frequently than with routine or standardized microscopic evaluation. Eighty-three percent of samples negative by microscopy were positive by PCR. CONCLUSION: PCR is more sensitive than microscopy for the detection of clonal lymphocytes in peripheral blood. The results of this study also suggest that neoplastic lymphocytes circulate in peripheral blood at a higher frequency than previously reported. PCR may be useful for detecting or phenotyping lymphoma, monitoring response to therapy, identifying recurrence, and screening breeds at risk. 相似文献
80.
Six R Cherni J Chesebrough R Cleaver D Lindeman CJ Papp G Skogerboe TL Weigel DJ Boucher JF Stegemann MR 《Journal of the American Veterinary Medical Association》2008,233(3):433-439
OBJECTIVE: To evaluate the efficacy and safety of administration of cefovecin, compared with cefadroxil, for treatment of naturally occurring secondary superficial pyoderma, abscesses, and infected wounds in dogs. DESIGN: Multicenter, randomized, positive-controlled clinical trial. ANIMALS: 235 client-owned dogs. PROCEDURES: Dogs with clinical signs of skin infection confirmed via bacteriologic culture were randomly allocated to receive a single SC injection of cefovecin (8 mg/kg [3.6 mg/lb]) followed by placebo administered PO twice daily for 14 days or cefadroxil (22 mg/kg [10 mg/lb]) administered PO twice daily for 14 days following a placebo injection. Two 14-day treatment courses were permitted. Treatment success was defined as reduction of clinical signs to mild or absent at the final assessment. RESULTS: Clinical efficacy achieved with cefovecin in dogs was equivalent to that observed with cefadroxil. At the final assessment, 14 days following the completion of treatment (on day 28 or 42), 92.4% (109/118) of the cefovecin group and 92.3% (108/117) of the cefadroxil group were treatment successes. There were no serious adverse events or deaths related to treatment. CONCLUSIONS AND CLINICAL RELEVANCE: A single cefovecin injection (8 mg/kg) administered SC, which could be repeated once after 14 days, was safe and effective against naturally occurring skin infections in dogs and as effective as cefadroxil administered PO twice daily for 14 or 28 days. 相似文献