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   394篇
  免费   0篇
  国内免费   2篇
综合类   1篇
化学工业   8篇
机械仪表   3篇
建筑科学   1篇
能源动力   1篇
轻工业   2篇
无线电   4篇
一般工业技术   2篇
冶金工业   366篇
自动化技术   8篇
  2022年   1篇
  2020年   1篇
  2019年   3篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2013年   3篇
  2010年   1篇
  2009年   2篇
  2007年   1篇
  2006年   1篇
  2004年   1篇
  2003年   4篇
  2002年   3篇
  2000年   1篇
  1999年   7篇
  1998年   111篇
  1997年   59篇
  1996年   36篇
  1995年   27篇
  1994年   18篇
  1993年   13篇
  1991年   3篇
  1990年   6篇
  1989年   4篇
  1988年   8篇
  1987年   4篇
  1986年   8篇
  1985年   5篇
  1983年   2篇
  1982年   2篇
  1981年   3篇
  1980年   2篇
  1977年   22篇
  1976年   27篇
  1975年   2篇
  1968年   1篇
  1964年   1篇
排序方式: 共有396条查询结果,搜索用时 15 毫秒
191.
This study compared three radionuclide techniques in distinguishing musculoskeletal infection from noninfectious inflammation. METHODS: Thirty-five orthopedic patients with suspected musculoskeletal infection were examined using three radionuclide techniques in sequence: triphasic bone scintigraphy, 99mTc radioleukocytes (99mTc-WBC) scintigraphy and 99mTc human immunoglobulin (99mTc-Hig) scintigraphy. Two "early" and "late" acquisitions were performed, at 4-6 hr and 20-24 hr postinjection, respectively. Patients who were diagnosed as suffering from noninflammatory lesions became the controls. We calcu"late"d for all studies one index of inflammation (Infl) as the ratio between counts in the uptake area and counts in an equal area of normal tissue. RESULTS: The "early" radiolabeled leukocytes and "late" Hig scintigraphy allowed the greatest ability to distinguish between infections and noninfectious inflammations (p < 0.011 and p < 0.016) with a sensitivity of 96.6% and 96.5% and specificity of 71% and 100%, respectively. Hig and radioleukocytes allowed distinguishing infections from noninflammatory diseases at both examinations. CONCLUSION: The "early" radioleukocyte scintigraphy allowed us to separate infections from noninfectious inflammations. In contrast, the same result can be obtained only with the "late" scan in the Hig study, but Hig mapped the spread of the inflammation into soft tissues better. Hig might be an alternative to radioleukocytes because of its simple preparation, similar accuracy and safety.  相似文献   
192.
In general pediatric clinic 262 children aged 1-15 years with functional hyperthermia, functional disorders of cardiac rhythm (extrasystole, paroxysmal and recurrent tachycardia), arterial hyper- and hypotension, autonomic dysfunctions were examined. 21 children with organic cardiac diseases were examined too. Mental disorders were revealed in all the cases: mono- and bipolar affective disorders (58.1%) as well as affective-dilutional (10.4%) states, primarily in the form of "masked" hypomanias, neurotic and neurotic-like (16.2%), psychopathic and psychopathic-like (7.0%), psychoorganic (3.7%) and epileptiform (4.6%) syndromes. The spectrum of mental disorders was extremely wide--from practical normal (in limits of reactions of personal accentuations or age crisis) to endogenic diseases. Combined treatment including drug therapy, psychotherapy and family correction was quite effective.  相似文献   
193.
Parametric-linkage analysis applied to large pedigrees with many affected individuals has helped in the identification of highly penetrant genes; but, for diseases lacking a clear Mendelian inheritance pattern or caused by several genes of low to moderate penetrance, a more robust strategy is nonparametric analysis applied to small sets of affected relatives, such as affected sib pairs. Here we show that the robustness of affected-sib-pair tests is related to the shape of the constraint set for the sibs' identity-by-descent (IBD) probabilities. We also derive a set of constraints for the IBD probabilities of affected sib triples and use common features of the shapes of the two constrain sets to introduce new nonparametric tests (called "minmax" tests) that are more robust than those in current use. Asymptotic-power computations support the robustness of the proposed minmax tests.  相似文献   
194.
Bacteriorhodopsin (BR) from Halobacterium salinarum as well as halorhodopsin (pHR) and sensory rhodopsin II (pSRII) from Natronobacterium pharaonis were functionally expressed in E. coli using the method of Shimono et al. IFEBS Lett. (1997) 420, 54-56]. The histidine tagged proteins were purified with yields up to 1.0 mg/l cell culture and characterized by ESI mass spectrometry and their photocycle. The pSRII and pHR photocycles were indistinguishable from the wild type proteins. The BR photocycle was considerably prolonged. pSOII is located in the cytoplasmic membrane and the C-terminus is oriented towards the cytoplasm as determined by immunogold labelling.  相似文献   
195.
The aim of this study was to determine whether the prevention of stroke with perindopril treatment in stroke-prone spontaneously hypertensive rats (SHRSP) is associated with the preservation of the myogenic properties of the cerebral arteries. After weaning at 4 weeks of age, male SHRSP were fed a Japanese-style rat diet with high salt to induce stroke development. Treatment with perindopril was given by gavage every morning beginning at 6 weeks of age. There were three experimental groups: two groups treated with 4 mg.kg-1.day-1 perindopril for different durations (8 or 12 weeks) and one control group consisting of littermates given distilled water. All the control animals developed stroke and died within 14 weeks of age, and myogenic response of the middle cerebral arteries (MCA) to pressure increase was lost in these animals. In contrast, all the treated SHRSP survived during the treatment period, and myogenic response of the MCA was preserved. After withdrawal of the treatment, SHRSP treated for a longer period (12 weeks) also survived longer than those treated for a shorter period (8 weeks). The subsequent development of stroke and death following treatment withdrawal after 8 or 12 weeks of treatment was associated with the loss of pressure-dependent constriction in MCA. A longer treatment duration also increased the stiffness of the MCA, MCA from SHRSP after 12 weeks of treatment had smaller external and lumen diameters, and thicker walls than those from the 8-week treatment group. In a separate study, we found that treatment of SHRSP with 1 or 4 mg.kg-1.day-1 of perindopril for 24 weeks beginning at 6 weeks of age also protected them against death related to stroke, because these rats survived up to 43 weeks of age, when the experiment was terminated. We conclude that there is an association between the absence of myogenic response in cerebral arteries and stroke development in SHRSP. Perindopril treatment preserves the myogenic response of MCA in SHRSP and prevents the stroke development in these animals. A prolonged treatment could increase the survival of SHRSP through a remodelling of the MCA and increasing the stiffness of the cerebral arteries.  相似文献   
196.
197.
198.
Comparative analysis of the methods of estimation of the state of fibrinolytic system and its components, which are used in clinical practice now is presented in the review. The advantages of the approaches, which are based on the simultaneous determination of several indices of this system were considered. It was shown promising to use these methods in ophthalmology for estimation of both common and local (in liquids and eye tissues) haemostats, as important additional diagnostic and prognostic criteria of development of some ophthalmopathologies.  相似文献   
199.
A puppy was presented with unilateral Horner's syndrome thought to have been in existence since the eyes first opened. No other clinical signs were evidence and the condition was attributed to trauma during assisted birth. All abnormalities resolved spontaneously by 11 weeks of age.  相似文献   
200.
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