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   240篇
  免费   10篇
  2022年   9篇
  2021年   9篇
  2019年   3篇
  2017年   5篇
  2016年   9篇
  2015年   13篇
  2014年   7篇
  2013年   15篇
  2012年   18篇
  2011年   17篇
  2010年   11篇
  2009年   12篇
  2008年   9篇
  2007年   6篇
  2006年   9篇
  2005年   6篇
  2004年   6篇
  2003年   4篇
  2002年   4篇
  2001年   2篇
  2000年   4篇
  1999年   2篇
  1998年   4篇
  1996年   3篇
  1993年   2篇
  1992年   3篇
  1991年   3篇
  1990年   6篇
  1989年   2篇
  1987年   2篇
  1986年   3篇
  1985年   2篇
  1984年   2篇
  1983年   3篇
  1982年   3篇
  1981年   2篇
  1980年   3篇
  1979年   3篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1975年   2篇
  1974年   1篇
  1973年   1篇
  1972年   3篇
  1971年   2篇
  1970年   3篇
  1969年   1篇
  1967年   1篇
  1961年   1篇
排序方式: 共有250条查询结果,搜索用时 15 毫秒
1.
Fourier transform infrared (FTIR) spectroscopic imaging is an emerging microscopy modality for clinical histopathologic diagnoses as well as for biomedical research. Spectral data recorded in this modality are indicative of the underlying, spatially resolved biochemical composition but need computerized algorithms to digitally recognize and transform this information to a diagnostic tool to identify cancer or other physiologic conditions. Statistical pattern recognition forms the backbone of these recognition protocols and can be used for highly accurate results. Aided by biochemical correlations with normal and diseased states and the power of modern computer-aided pattern recognition, this approach is capable of combating many standing questions of traditional histology-based diagnosis models. For example, a simple diagnostic test can be developed to determine cell types in tissue. As a more advanced application, IR spectral data can be integrated with patient information to predict risk of cancer, providing a potential road to precision medicine and personalized care in cancer treatment. The IR imaging approach can be implemented to complement conventional diagnoses, as the samples remain unperturbed and are not destroyed. Despite high potential and utility of this approach, clinical implementation has not yet been achieved due to practical hurdles like speed of data acquisition and lack of optimized computational procedures for extracting clinically actionable information rapidly. The latter problem has been addressed by developing highly efficient ways to process IR imaging data but remains one that has considerable scope for progress. Here, we summarize the major issues and provide practical considerations in implementing a modified Bayesian classification protocol for digital molecular pathology. We hope to familiarize readers with analysis methods in IR imaging data and enable researchers to develop methods that can lead to the use of this promising technique for digital diagnosis of cancer.  相似文献   
2.
Spleen extracts from WLH chickens nonsensitized and sensitized by repeated infections of Ancylostoma caninum larvae were injected separately into isologous recipients. Extracts from donors infected with repeated high dose (250 + 250 + 500) and low dose (125 + 125 + 250) of larvae induced a significant acquired protective immune response when compared to controls which received normal extracts. No significant difference was observed between the two experimental groups. The filariform Ancylostoma caninum larvae which can cause cutaneous larva migrans in man are found to be carried by a variety of paratenic hosts. Several studies from this lab have shown that the white leg horn (WLH) chicken successfully sustains and also responds immunologically to this parasite. The present authors have also shown that extracts of bursae of Fabricius and spleens of immunized chickens can induce immunity in syngeneic recipients. Here an attempt has been made to investigate whether repeatedly sensitized extracts of A. caninum infected chickens can cause expulsion of a challenge dose from the recipients.  相似文献   
3.
Summary Production of lipase by free and alginate-entrapped protoplasts was studied in batch culture. Cell-wall-degrading enzymes Novozym 234 and cellulase CP improved lipase secretion of normal mycelium by 25%–100%. The protoplast-regenerated mycelium exhibited several-fold higher lipase activity in batch replacements in TRIS buffer over normal spore-derived mycelium. The specific lipase activity of immobilized protoplasts was about four times higher than normal mycelial beads. Protoplasts beads were stable and retained high enzyme activity even after three buffer replacements lasting 120 h; TRIS buffer was better than acetate or normal glucose medium. A minimum of 8 h regeneration period was necessary for lipase synthesis. Triolein, olive oil, tributyrin and oleic acid butylester were able to induce lipase in immobilized protoplasts. Tween 80 enhanced lipase activity of the immobilized protoplasts. Partially degraded immobilized mycelium was nearly as effective as normal immobilized protoplasts for lipase secretion. Both free and immobilized protoplasts could be reused for up to 200 h with some loss in enzyme activity.  相似文献   
4.
Erwinia herbicola (ATCC 21998), a facultative anaerobe, has two plasmids: pVQ1 and pVQ2. Curing with mitomycin C indicated that pVQ2 was cryptic but pVQ1, a 7.4-kb plasmid, bears a 4.3SacI fragment which strongly hybridized to the C-terminal region of the glucose dehydrogenase gene ofAcinetobacter calcoaceticus. A restriction map of plasmid pVQ1 is presented.The authors are with the Department of Biotechnology, Regional Research Laboratory, Canal Road, Jammu Tawi-180 001, India;  相似文献   
5.
Activities of Phosphorylase, glyceraldehyde-3 -phosphate dehydrogenase, lactate dehydrogenase, malate dehydrogenase and succinate dehydrogenase in the rat endometrial tissue are significantly inhibited by an intrauterine copper device, while it stimulated glucose-6-phosphate dehydrogenase activity. The copper device decreased the lactate/pyruvate ratio in the tissue; pyruvate utilizationin vitro by the rat endometrium is also blocked by copper. These findings suggested that the normal carbohydrate metabolism of the tissue may be affected in presence of copper, thus resulting in a change of the endometrial function, which may be one of the factors responsible for the contraceptive and pharmacological action of an intrauterine copper device.  相似文献   
6.
Populations of the annualPhaseolus sublobatus from different ecogeographical zones are genetically differentiated. In twelve populations from the western ghats (Maharashtra range) chasmogamous flowers are arranged in peduncled capitate racemes borne in leaf axils of higher nodes. One population (Poona Race S4) has additional inflorescences, also with chasmogamous flowers, on the main axis between the cotyledonary node and the ground. When the pods of these flowers ripen, the inflorescence gradually coils and, eventually, gets bury the fruits in the soil. This phenomenon is not known in any other plant.—The seed-coat patterns as revealed by SEM, and germination behaviour of both aerial and subterranean seeds are similar, and both types of seeds lack dormancy.—Heavy seed predation selection pressure is probably the principal cause for the evolution of fruit dimorphism inP. sublobatus. The origin of geocarpy in relation to fruit dimorphism and seed predation is discussed.  相似文献   
7.
Summary Rhodococcus equi cells immobilized onto porous celite beads were active in side-chain cleavage of cholesterol. The effect of bead size, adsorption time and washing cycles were examined. The degradation of cholesterol side-chain using adsorbed cells was studied in batch and semi-continuous systems. Compared to free cells (80 mol%), the end-product (1,4-androstadiene-3,17-dione and 4-androstene-3,17-dione) profile was lower (70 mol%) with the celite-adsorbed system. Correspondence to: B. N. Johri  相似文献   
8.
A wild-type strain of Rhodococcus equi, isolated from soil, degraded cholesterol, -sitosterol, stigmasterol and mixed sterois to androst-4-ene-3,17-dione (AD) and androsta-1,4-diene-3,17-dione (ADD). A definite preference for a relatively simply structured cholesterol side chain was observed. Highest specific cholesterol side-chain cleavage was associated with active growth of the culture. Maximum yield of ADD was obtained when sodium acetate and cholesterol were incorporated together in the medium. Specific side-chain cleavage required the presence of 2,2-dipyridyl, an inhibitor of ring cleavage.S. Ahmad and B.N. Johri are with the Department of Microbiology, College of Basic Sciences and Humanities, G.B. Pant University of Agriculture and Technology, Pantriagar 263 145, Nainital, UP, India. P.K. Roy, A.W. Khan and S.K. Basu are at Fermentation Technology Division, Central Drug Research Institute, Lucknow, India.  相似文献   
9.
10.
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) offer a potent and effective alternative for treatment of antibiotic resistant microbes. Mastoparans or...  相似文献   
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