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41.
By using the leaves with attached intercalary meristems from greenhouse grown stock plants, five cultivars of Cryptanthus were cultured on modified MS media with 4.5 μM NAA and IBA and 3 μM BA to induce adventitious shoot formation from callus tissue. Contamination was 17–21% for explants taken from stock plants which were sprayed weekly with Agribrom and 27–75% for those taken from stock plants which were not treated. More than 99% true to type plantlets were obtained from non-chimeric plants. Green and albino plantlets were obtained from chimeric plants. The chimeric C. ‘Coster's Favorite’ DeCoster also produced a few chimeric plantlets with intermarginal pink stripes in addition to the green and albino plantlets. Most of the non-chimeric plants took a shorter time to produce plantlets of transplantable size (8–12 mm) than the chimeric ones. Except for albino plantlets, survival rate of plantlets exceeded 95%. A minimum average of 500 rooted plantlets can be obtained in a year from a single well-callused leaf explant. The protocol in this report should speed up the mass production and introduction of desirable new cultivars and hybrids of non-chimeric Cryptanthus. 相似文献
42.
David A. Lidbetter BVSc MVS CertSAS MACVSc MRCVS Fred A. Williams Jr. DVM Diplomate ACVS D. J. Krahwinkel DVM MS Diplomate ACVS ACVA ACVECC William H. Adams DVM Diplomate ACVR 《Veterinary surgery : VS》2002,31(1):57-64
OBJECTIVE: To describe and evaluate a technique for radical resection of the lateral body wall for treatment of fibrosarcoma with reconstruction using polypropylene mesh and a caudal superficial epigastric axial pattern flap in cats. STUDY DESIGN: Prospective, clinical study. ANIMALS OR SAMPLE POPULATION: Six client-owned cats with fibrosarcoma. METHODS: Six cats with histologically confirmed fibrosarcoma of the lateral body wall were staged using radiography and/or computer tomography scanning. Preoperative radiotherapy was used in 3 cats. All cats had the lateral abdominal wall resected and reconstructed with polypropylene mesh. A caudal superficial epigastric flap was mobilized and rotated to close the skin deficit. The animals were evaluated after surgery for wound complications, tumor recurrence, and metastasis. Outcome was assessed by patient examination and client consultation. RESULTS: Minor dehiscence of the skin flaps occurred in 2 cats, and 1 other cat was successfully resuscitated from respiratory and cardiac arrest after surgery. All tissue specimens were tumor-free at the surgical margins. Follow-up times ranged from 12 to 21 months, with a mean time of 17.2 months. None of the cats had evidence of local tumor recurrence or metastasis; outcome was judged good to excellent in all cats. CONCLUSIONS AND CLINICAL RELEVANCE: Radical lateral body-wall resection and reconstruction is an effective technique for achieving local tumor control with acceptable patient morbidity. Further studies are needed to assess whether the technique will result in improved tumor-free intervals and survival times. 相似文献
43.
David A. Barlow Ph.D. Judith M. Lloyd B.S. HT Paul Hellhake B.S. Jeffrey A. Seder J.D. M.B.A. 《Journal of Equine Veterinary Science》1984,4(2):60-66
Equine skeletal muscle was histologically and histochemically analyzed in orderto measure fiber composition. Well-sampled open muscle biopsies were obtained from the semitendinosus muscle in select yearling Thoroughbreds. Each biopsy was sectioned and stained for the Harris Hematoxylin and Eosin and the modified Gomori Trichrome in order to demonstrate the basic muscle fiber morphology delineating intra and extracellular elements. A thirdstain, CA++ activated myosin Adenosine Triphosphatase at pH 9.4 was used to differentiate between specific types on the basis of enzyme activities. Subsequent differentiation of Type I slow twitch and Type II fast twitch muscle fibers was assessed on the basisof staining intensity. The high predominance of Type II fast twitch fibers ranged from 85.1 to 100 % with a mean of 90.5 %. Racing records, as two- and three-year-olds, were monitored in order to qualitatively compare histochemical results with performance achievements. While caution must be exercised, results of this investigation suggested that it may be possible, at an early age to partially predict the potential of each horse to adapt to training and to compete successfully in races of varying distances. 相似文献
44.
R M Barlow N F Suttle M B Derbyshire A C Gardiner J C Rennie 《The Veterinary record》1976,98(5):86-88
The proposal that hypocupraemia and hypocuprosis are characteristic manifestations of Border disease and of aetiological significance has been investigated. Mean plasma copper concentrations in 65 affected and 47 unaffected lambs were similar and in a controlled experiment, plasma and tissue copper concentrations tended to be higher in affected lambs than in controls. It is concluded that hypocupraemia and hypocuprosis are not consistent features of Border disease and thus have no aetiological significance. 相似文献
45.
Alan B. Hadaway Fred Barlow Christopher R. Turner Leonard S. Flower 《Pest management science》1977,8(2):172-176
Tests to evaluate candidate insecticides and formulations for tsetse control are described, and some data are presented to indicate that some new synthetic pyrethroids (e.g. permethrin and NRDC 161) are effective for a long period at such extremely low doses that they could have a pronounced influence on future tsetse control operations. 相似文献
46.
47.
In the present study we report on the histotopographical distribution of lectin binding sites in the trophoblasts of day 18 to day 40 bovine embryos, using the FITC-labeled lectins BPA, Con A, DBA, GS I, GS II, MPA, PNA, SBA, UEA I and WGA. Lectin binding sites localized in giant binucleate cells differ from those localized in uninucleate cells, indicating changes in the biochemical structure of cell surfaces taking place during differentiation. In the trophoblast of the day 40 embryo, a distinct staining of uninucleate cells was seen after incubation with GS I, Con A and MPA, demonstrating N-acetylgalactosamine (GS I), Mannose (Con A) and Galactose (MPA) moieties, whereas giant binucleate cells showed intense reactions after incubation with DBA and WGA, indicating presence of N-acetylgalactosamine (DBA) and N-acetylglucosamine (WGA). GS II (specific for N-acetylglucosamine), SBA (specific for N-acetylgalactosamine) and UEA I (specific for L-Fucose) showed no affinity toward any of the examined tissues. We assume, that carbohydrate moieties in trophoblast cells play an important role in fetomaternal cell-cell adhesion and cell migration during implantation and placentation period. 相似文献
48.
The objective of this study was to assess the stability of ELISA plates prepared with one of three blocking agents and used with one of two conjugates at various time intervals after preparation of the plates. Two of the blocking agents used were commercially available: one termed stabilgaurd (stab) and one manufactured by SVANOVA Biotek AB Inc. (svan). The third blocking agent used was bovine serum albumin (bsa). A polyclonal rabbit anti-bovine IgG (poly) and an anti-bovine IgG monoclonal (mono) conjugate were used. Eighteen composite individual cow milk samples collected late in lactation (200-400 days in milk) were used in this study. An indirect microtitre plate ELISA that used the Ostertagia ostertagi antigen was used to quantify antibodies against the parasite, present in the milk samples. Each of six blocking agent/conjugate combinations (called systems) were used to test 18 milk sub-samples at 1, 4 and 24 weeks after blocking the plates. Plates blocked with stab and svan were kept at room temperature and an additional set were incubated at 37 degrees C so as to mimic long term storage (about 1 year) and tested only once at 4 weeks. Those blocked with bsa were frozen at -20 degrees C. Concordance correlation coefficients (CCC) and reproducibility were used to assess the agreement between test results conducted on the same milk sample at the various test-times using a particular system. Generally, there was good agreement between tests conducted at different times for all systems. However, the svan-mono and bsa-poly systems had the best agreement with overall CCC values of 96% and 93%, respectively. The svan-poly system had the lowest CCC of 75%. The CCC and reproducibility ranked the systems in a similar way. The high CCC between tests done using plates kept at room temperature and ones incubated at 37 degrees C, suggested that plates would be stable up to a year after blocking. The storage of plates blocked with svan and stab agents under room temperature, makes them more convenient to use and transport relative to bsa-blocked plates that have to be frozen. 相似文献
49.
Inocula derived from two sources of typical border disease (BD) and designated BP-77 and H-77 respectively, were prepared and injected into pregnant ewes of four breeds. The BP-77 inoculum produced higher serum neutralising antibody titres to the cytopathic BD virus than to the NADL strain of bovine virus diarrhoea virus. Only typical BD occurred among the progeny of all four breeds. In contrast H-77 produced higher titres to bovine virus diarrhoea than to BD and typical BD occurred only in the progeny of two of the four breeds. Progeny of the other two breeds appeared normal or had a range of malformations of the central nervous system but none of the characteristic clinical or pathological stigmata of BD. The existence of more than one strain of BD virus is confirmed. Virus strain/host genotype interactions may affect the character of disease in the progeny. The possible implications for diagnosis and control are discussed. It is concluded that the generally accepted criteria for diagnosis of BD are no longer adequate and that the disorder should be redesignated. 相似文献
50.
Fred P. Sprinkle D.V.M. M.S. T.W. Swerczek D.V.M. PhD. M. Ward Crowe D.V.M. 《Journal of Equine Veterinary Science》1984,4(4):175-176
Meckel's diverticulum is a remnant of the vitellointestinal duct. It is through this duct that nutrients pass from the yolk sac into the midgut of the four-week-old embryo. In a review of 15,000 postmortem records at the University of Kentucky, Meckel's diverticulum was observed in five horses examined postmortem. In each case, the diverticulum was a factor in the animal's death. In light of these statistics, Meckel's diverticulum may not be as frequent a finding in the horse as has been previously considered. 相似文献