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301.
Erika R. Mueller 《Journal of Veterinary Emergency and Critical Care》2001,11(3):191-198
Objective: To review the current recommendations and guidelines for mechanical ventilation in humans and in animals with acute respiratory distress syndrome.
Human data synthesis: Acute respiratory distress syndrome (ARDS) in humans in defined as an acute onset of bilateral, diffuse infiltrates on thoracic radiographs that are not the result of heart disease and a significant oxygenation impairment. These patients require mechanical ventilation. Research has shown that further pulmonary damage can occur as a result of mechanical ventilation. Various alveolar recruitment maneuvers and a low tidal volume with increased positive end expiratory pressure (PEEP) have been associated with an increased survival.
Veterinary dat synthesis: Two veterinary reports have characterized ARDS in dogs using human criteria. There are no prospective veterinary studies using recruitment that ventilator-induced lung injury (VILI) occurs in dogs, sheep, and rats.
Conclusion: Recruitment maneuvers in conjunction with low tidal volumes and PEEP keep the alveoli open for gas exchange and decrease VILI. Prospective veterinary research in needed to determine if these maneuvers and recommendation can be applied to veterinary patients. 相似文献
Human data synthesis: Acute respiratory distress syndrome (ARDS) in humans in defined as an acute onset of bilateral, diffuse infiltrates on thoracic radiographs that are not the result of heart disease and a significant oxygenation impairment. These patients require mechanical ventilation. Research has shown that further pulmonary damage can occur as a result of mechanical ventilation. Various alveolar recruitment maneuvers and a low tidal volume with increased positive end expiratory pressure (PEEP) have been associated with an increased survival.
Veterinary dat synthesis: Two veterinary reports have characterized ARDS in dogs using human criteria. There are no prospective veterinary studies using recruitment that ventilator-induced lung injury (VILI) occurs in dogs, sheep, and rats.
Conclusion: Recruitment maneuvers in conjunction with low tidal volumes and PEEP keep the alveoli open for gas exchange and decrease VILI. Prospective veterinary research in needed to determine if these maneuvers and recommendation can be applied to veterinary patients. 相似文献
302.
Intramuscular fat content and genetic variants at fatty acid-binding protein loci in Austrian pigs. 总被引:9,自引:0,他引:9
D Nechtelberger V Pires J S?olknet G SturBrem M Mueller S Mueller 《Journal of animal science》2001,79(11):2798-2804
Intramuscular fat is an important meat quality trait in pig production. Previously, genetic variants of the heart fatty acid-binding protein (H-FABP) gene and the adipocyte fatty acid-binding protein (A-FABP) gene were suggested to be associated with intramuscular fat content. The objective of this investigation was to study these associations in the three most important Austrian breeding populations (Piétrain, Large White, and Landrace). Restriction fragment length polymorphism analysis of the H-FABP gene revealed a new MspI polymorphic site and genetic variation in all three breeds. Microsatellite analysis of the A-FABP locus showed up to nine different microsatellite alleles segregating. In Austrian breeds, no significant influence of the A-FABP and H-FABP gene polymorphisms on intramuscular fat could be detected. We also evaluated possible associations between the genetic variations at the H-FABP and A-FABP loci and other growth and carcass traits (average daily gain, feed conversion ratio, lean meat content, pH values, meat color, and drip loss). With regard to the extent of the effects, these genetic markers cannot be recommended for selection on growth and carcass traits in Austrian breeding populations. 相似文献
303.
Prevention and treatment of gastrointestinal adhesions. 总被引:3,自引:0,他引:3
Randall B Eggleston P O Eric Mueller 《Veterinary Clinics of North America: Equine Practice》2003,19(3):741-763
As with many aspects of clinical medicine, there is yet to be a single or definitive cure for postoperative adhesion formation. Current methods of prevention target risk factors predisposing horses to adhesion formation. Systemic pharmacologic therapies, such as antimicrobials, nonsteroidal anti-inflammatory drugs, Salmonella antiserum, and hyperimmune plasma, help to reduce abdominal inflammation and minimize the effects of endotoxemia. Intra-abdominal or systemic heparin aids in enhancing peritoneal fibrinolysis. Prokinetic therapy promotes early postoperative return of intestinal motility, minimizing the propensity for adhesion formation between apposing adynamic segments of intestine. Mechanical separation of potentially adhesiogenic serosal and peritoneal surfaces is commonly achieved with use of abdominal lavage, protective coating solutions, and barrier membranes. Ongoing and future research is directed toward a better understanding of the local effects of intestinal trauma and the corresponding response of the fibrinolytic system. Recognition of horses at high risk for adhesion formation helps to guide the equine surgeon to an appropriate perioperative and intraoperative plan for adhesion prevention, including good surgical technique and a combination of adjunct therapies. 相似文献
304.
A. Moulaert J.P. Mueller M. Villarreal R. Piedra L. Villalobos 《Agroforestry Systems》2002,54(1):31-40
A silvopastoral model that combines the production of pasture herbage with valuable native timber species has potential to
simultaneously address the multiple goals of reforestation, conservation of native species and enterprise intensification.
The objective of this study was to design, establish and monitor early growth of a silvopastoral experiment on a dairy farm
in the north Atlantic zone of Costa Rica. Two indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were planted with and without the tropical pasture legume, Arachis pintoi in a split plot design, (2 × 2) factorial arrangement of treatments with four replications. After the first two years, V. guatemalensis was significantly taller (3.1 m) than H. alchorneoides (2.5 m). The mean root collar diameter for V. guatemalensis was significantly larger (6.5 cm) than H. alchorneoides (4.5 cm). Two-year establishment was acceptable for the tree component (83 to 85% survival) but poor for A. pintoi (2 to 8% of the sward). The most important pest affecting the establishment of the timber species was the leaf cutter ant,
Atta cephalotes. An insect larvae, Cosmopterix sp., severely damaged 39% of the V. guatemalensis trees by repeatedly attacking their apical meristems. The two-year establishment data was insufficient to accurately predict
future wood volume. A hypothetical economic analysis concluded that the silvopastoral system must average at least 1.2 m3 wood volume/paddock/year (20 m3/ha/year) throughout the first ten years of growth to assure a positive economic return from timber. The experiment is planned
for a ten year period, which corresponds to the estimated rotation length for harvesting the timber species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
305.
Lemma W Mengistu George W Mueller‐Warrant Aaron Liston Reed E Barker 《Pest management science》2000,56(3):209-217
The herbicide‐binding region of the chloroplast psbA gene from a total of 20 biotypes of Poa annua L resistant and susceptible to metribuzin and diuron was selectively amplified using PCR. Sequence analysis of the fragment from six herbicide‐resistant biotypes of P annua exhibited a substitution from valine to isoleucine at position 219 of the D1 protein encoded by the psbA gene. This is the same mutation as reported for Chlamydomonas and Synechococcus through site‐directed mutagenesis and in cell cultures of Chenopodium rubrum L. To our knowledge this is the first report of a higher plant exhibiting resistance in the field to photosystem II inhibitors due to a psbA mutation other than at position 264. The existence of additional biotypes of P annua resistant to diuron or metribuzin but lacking mutation in the herbicide‐binding region indicates that resistance to these herbicides can also be attained by other mechanisms. © 2000 Society of Chemical Industry 相似文献
306.
乳牛舍内外环境空气中需氧菌,厌氧菌以及产气荚膜杆菌的定量分析 总被引:7,自引:0,他引:7
应用Andersen-多层级微生物收集器和KS-92 液体喷冲器,对乳牛舍内、外空气细菌含量,即厌氧菌、需氧菌总数以及产气荚膜杆菌(魏氏梭菌)进行了定性定量分析。结果表明,舍内空气中厌氧菌总数达到2098~4 295 个/m 3 ,其中魏氏梭菌为0~5.5 个/m 3 (Andersen-收集器);同时在舍内空气中,需氧菌总数为2050~18 094 个/m 3 。在舍邻近(4 m 处)的环境空气中厌氧菌总数为239~2 282 个/m 3 ,其中魏氏梭菌0~2.0个/m 3 ;需氧菌总数为297~4 276 个/m 3 。结果证明,舍内环境的细菌能向舍外环境传播,舍内、外环境微生物含量的高低浮动反映了舍内的卫生状况。 相似文献
307.
产气荚膜梭状芽孢杆菌气悬状态下存在形式的研究 总被引:1,自引:0,他引:1
产气荚膜梭状芽孢杆菌是动物舍空气粪便污染的指示菌种,他们的含量反映了动物舍卫生状况以及动物体相应疾病的可能感染。通过对 K S92 喷冲器空气样品加热 80℃,20 分钟处理,结果证明该菌群几乎 100% 以芽孢形式气悬存在。 相似文献
308.
The establishment and early growth of three leguminous tree species for use in silvopastoral systems of the southeastern USA 总被引:1,自引:0,他引:1
Demand for goat meat in the eastern USA is growing as a result of preference by ethnic communities. Meat goat production systems
in the southeastern USA should be designed to take advantage of the goats' natural preference for browse. Trees could contribute
to system productivity by supplying required nutrients when demand by growing animals is critical and the quality of forage
is limited. A field study was established in Wake County, NC to evaluate the establishment and early growth characteristics
of three leguminous tree species, Robinia pseudoacacia, Gleditsia triacanthos, and Albizia julibrissin. The three tree species
were planted in single-row plots following a randomized complete block design (3 × 2 × 2, replicated six times) with two planting
densities (intra-row spacing of 50 or 100 cm) and two coppice heights (25 or 50 cm). Bare-root seedlings were planted in March
1995, evaluated for browse quality (composited samples) in August 1995, coppiced in February 1996, evaluated for herbage mass
and quality in July 1996, and evaluated for goat preference in August 1996. Herbage mass produced during the second season
ranged from about 200 (G. tricanthos) to 3,200 kg/ha (R. pseudoacacia). Estimates of herbage quality were high for all species.
Crude protein and acid detergent fiber of leaflets ranged from 23 to 28% and 12 to 22%, respectively. Robinia pseudoacacia
has a high potential as a browse species for goats due to high herbage production (mean of 2,390 kg/ha) and goat preference.
Gleditsia triacanthos was judged to be a low value browse species. Albizia julibrissin, although not highly preferred by goats
in the trial holds sufficient potential to warrant further investigation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
309.
Abstract.– The effects of culture rope density (high and low), position (inside, middle. and outside), and depth (1, 3, and 5 m) on growth rates, expressed as mean shell length increase (mm) per day, were quantified in raft-cultured blue mussels Mytilus trossulus in northern Puget Sound during the fall of 1993. Growth rates differed by as much as 20% after the 90-d experimental period, and varied significantly according to culture rope position, but not according to culture rope density or depth. Furthermore, a three-way analysis of variance revealed a significant first-order interaction effect, culture rope density × depth. The significant culture rope position effect was due to the higher growth rate (mean ± SEM) of mussels on outside culture ropes (0.199 ± 0.009 mm/d) compared to inside culture ropes (0.168 ± 0.007 mm/d). The interaction effect was due to the significantly higher growth rates of mussels at I and 3 m (0.197 ± 0.009 and 0.204 ± 0.011 mm/d, respectively) compared to 5 m (0.162 ± 0.014 mm/d) under low culture rope density conditions, and the significantly higher growth rate of mussels at 3 m under low culture rope density conditions (0.204 ± 0.011 mm/d) compared to high culture rope density conditions (0.168 ± 0.012 mm/d). Practical raft management is affected by such variation in growth. Commercial mussel growers may find it necessary to alter their culture methods to insure a more uniform product from seed to harvest. 相似文献
310.