首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   67篇
  免费   6篇
林业   1篇
综合类   9篇
畜牧兽医   62篇
植物保护   1篇
  2019年   2篇
  2018年   3篇
  2016年   2篇
  2015年   1篇
  2014年   1篇
  2013年   5篇
  2011年   3篇
  2010年   5篇
  2009年   2篇
  2008年   1篇
  2007年   1篇
  2006年   2篇
  2005年   2篇
  2004年   1篇
  2002年   3篇
  2001年   4篇
  2000年   2篇
  1999年   5篇
  1998年   7篇
  1997年   5篇
  1996年   3篇
  1995年   2篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1990年   2篇
  1989年   2篇
  1985年   1篇
  1982年   1篇
排序方式: 共有73条查询结果,搜索用时 31 毫秒
11.
12.
13.
A nasal mass in a Domestic Shorthair cat was causing facial deformity, sneezing and intermittent epistaxis. Biopsy samples obtained previously had been non-diagnostic. Computed tomography images revealed an irregular, contrast-enhancing mass occupying a large portion of the righthand side of the nasal cavity. Previously described criteria for malignancy were not present. A ventral surgical approach combined with temporary, ipsilateral, common carotid arterial occlusion provided excellent access for debulking the lesion and collecting samples for histopathology. A nasal vascular hamartoma was diagnosed and clinical signs resolved postoperatively. This is the first documentation of this abnormality in the cat. Hamartomatous abnormalities should be included on the list of differential diagnoses for feline nasal mass lesions. The prognosis for hamartomatous lesions postoperatively is good, in keeping with their limited propensity for growth after maturity.  相似文献   
14.
15.
16.
Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p6mm) silica-block copolymer mesophases. Calcination at 500 degrees C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35 degrees to 80 degrees C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140 degrees C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.  相似文献   
17.
X Bu  P Feng  GD Stucky 《Science (New York, N.Y.)》1997,278(5346):2080-2085
Zeolite type structures with large cages interconnected by multidimensional 12-ring (rings of 12 tetrahedrally coordinated atoms) channels have been synthesized; more than a dozen large-pore materials were created in three different topologies with aluminum (or gallium), cobalt (or manganese, magnesium, or zinc), and phosphorus at the tetrahedral coordination sites. Tetragonal UCSB-8 has an unusually large cage built from 64 tetrahedral atoms and connected by an orthogonal channel system with 12-ring apertures in two dimensions and 8-ring apertures in the third. Rhombohedral UCSB-10 and hexagonal UCSB-6 are structurally related to faujasite and its hexagonal polymorph, respectively, and have large cages connected by 12-ring channels in all three dimensions.  相似文献   
18.
19.
OBJECTIVE: To determine effects of duration of capture and sample-handling procedures on blood analytes in free-ranging bottlenose dolphins. DESIGN: Cross-sectional study. ANIMALS: 154 free-ranging bottlenose dolphins of various ages and both sexes. PROCEDURES: Blood samples were drawn from each dolphin within 10 minutes of capture and before release and analyzed by use of a portable analyzer with a single-use 8-analyte disposable cartridge. Analyte values were compared according to duration between sample acquisition and analysis (time to run [TTR]) and duration between net encirclement and sample acquisition (time to bleed [TTB]). RESULTS: Neither TTB nor TTR significantly affected sodium or chloride concentration. Potassium concentration was not significantly affected by TTR, whereas the effect of TTB was significant. Glucose, total CO(2), HCO(3), Hct, and base excess of extracellular fluid values were significantly affected by TTR. Increased TTB resulted in significantly increased total CO(2), HCO(3), and base excess when TTR was kept within 10 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: The effect of TTB on certain acid-base and electrolyte values was readily measured in free-ranging bottlenose dolphins, and such values may provide a reference range for those variables.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号