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   465篇
  免费   6篇
耳鼻咽喉   2篇
儿科学   1篇
妇产科学   13篇
基础医学   17篇
口腔科学   22篇
临床医学   67篇
内科学   118篇
皮肤病学   38篇
神经病学   8篇
外科学   47篇
一般理论   7篇
预防医学   38篇
眼科学   23篇
药学   68篇
肿瘤学   2篇
  2016年   4篇
  2015年   3篇
  2014年   3篇
  2013年   13篇
  2010年   11篇
  2009年   17篇
  2008年   4篇
  2005年   3篇
  2001年   5篇
  2000年   5篇
  1999年   11篇
  1998年   16篇
  1997年   18篇
  1996年   21篇
  1995年   24篇
  1994年   17篇
  1993年   18篇
  1992年   22篇
  1991年   16篇
  1990年   17篇
  1989年   20篇
  1988年   14篇
  1987年   8篇
  1986年   18篇
  1985年   14篇
  1984年   12篇
  1983年   17篇
  1982年   12篇
  1981年   14篇
  1980年   9篇
  1979年   9篇
  1978年   8篇
  1977年   4篇
  1976年   3篇
  1975年   7篇
  1974年   3篇
  1973年   3篇
  1972年   3篇
  1971年   3篇
  1970年   5篇
  1969年   3篇
  1968年   4篇
  1967年   6篇
  1966年   4篇
  1965年   2篇
  1963年   2篇
  1960年   4篇
  1956年   1篇
  1955年   2篇
  1954年   1篇
排序方式: 共有471条查询结果,搜索用时 46 毫秒
21.
22.
Day-case or outpatient cataract surgery has been reported many times over the past thirty years or so and the modern micro-surgical techniques were deemed safe enough to allow immediate ambulation and return to the home environment even with the additional step of implantation of an intra-ocular lens provided the lens were of the type designed for positive fixation. The trend also toward the planned extra-capsular method of cataract removal was thought to be a further safeguard to the patient, particularly the elderly age-group of patients for whom implants are strongly indicated and for whom also early ambulation and avoidance of general anaesthesia are important in reduction of morbidity.
Consequently, a study began in November,1976,to follow those patients who had the indication and the desire to have their implant surgery on a Day-case basis and this presentation gives the results on 100 cases collected over the 31/2 year period.
Local anaesthesia was used in all cases and planned extra-capsular surgery was performed with irrigating micro-instruments. Irido-capsular lenses of Binkhorst design were used mostly and the visual results, low complication rate and patient satisfaction appear equal to reports of similar series on In-patient cases.  相似文献   
23.
24.
The conformational properties of a number of calcitonin analogs were studied by circular dichroism. The ability of dimyristoylphosphatidylglycerol, lyso-phosphatidycholine or sodium dodecyl sulfate to induce the formation of more highly ordered structures in these peptides was also assessed by circular dichroism. In all cases sodium dodecyl sulfate induced the largest change in the circular dichroism spectra of the peptides. Salmon calcitonin and its analogs were slightly more helical in the presence of the anionic phospholipid than in the presence of the zwitterionic detergent lysophosphatidylcholine while the reverse is true for human calcitonin and its analogs. Some of the calcitonin analogs convert turbid suspensions of phosphatidylglycerol to a clear solution from which the phospholipid is no longer readily sedimentable by centrifugation. Several of the physical properties of these peptides could be correlated with their biological activity. Generally peptides which showed no hypo-calcemic activity had the least negative mean residue ellipticities at 222 nm. Only biologically active analogs were able quantitatively to solubilize dimyristoyl-phosphatidylglycerol and in this solubilized form the peptides have a higher helical content. More active derivatives exhibit larger increases in helix content in the presence of this phospholipid. Inactive analogs had the least negative mean residue ellipticities at 222 nm in the presence of lysophosphatidylcholine or sodium dodecyl sulfate. Thus, the ability of a calcitonin analog to form structures of higher helical content in the presence of amphiphiles is a requirement for the analog to exhibit high potency in assays of biological activity.  相似文献   
25.
26.
27.
Studies on Reproduction in Rats with Meclofenamate Sodium, aNonsteroidal Anti-inflammatory Agent. PETRERE, J. A., HUMPHREY,R. R., ANDERSON, J. A., FITZGERALD, J. E., AND DE LA IGLESIA,F. A. (1985). Fundam. Appl. Toxicol. 5, 665–671. Reproductionand teratology studies were performed in rats given meclofenamatesodium, a nonsteroidal anti-inflammatory agent. Dosages of 0,3, 6, and 9 mg/kg were administered orally as dietary admixturesin the Fertility and Perinatal-Postnatal studies. In the Teratologystudy, dosages of 10, 12, 15, and 20 mg/kg were administeredby intragastric intubation. In the Male-Fertility study no adverseeffects on fertility or litter and offspring parameters wereobserved in two generations. In the Female-Fertility and Perinatal-Postnatalstudies, maternal toxicity (death associated with intestinalulceration and adhesions) was particularly evident during lactation.Prolonged gestation periods, decreased weanling weights, andincreased weanling mortality were evident at dosages of 6 and9 mg/kg. Increased postimplantation loss occurred at 6 and 9mg/kg in the Term Sacrifice subgroup of the Female-Fertilitystudy. Fertility rates were unaffected and all other litterand offspring parameters of the F1 and F2 generations appearednormal. In the Teratology study no adverse effects on embryonicor fetal development were evident at maternally toxic dosagesup to 20 mg/kg. © 1985 Society of Texicology.  相似文献   
28.
Consumption of an ethanol-containing diet by mice resulted in a significant increase in circulating concentrations of corticosterone which was maintained for 8 days. There were no changes in the concentrations of plasma corticosterone binding globulin. Ethanol withdrawal symptoms followed the removal of ethanol from the diet and circulating corticosterone concentrations were further increased. There was no correlation between blood ethanol and glucocorticoid concentrations during the chronic ethanol treatment. Stress related to ethanol consumption may be of greater importance than the circulating ethanol concentrations in producing the elevation in plasma glucocorticoids.  相似文献   
29.
An inexpensive display and timing unit incorporating a multichannel signal delay has been developed for mapping the heart during electrophysiological surgery. It provides a continuous digital readout of the time relationships between 3 introcardiac electrograms and the surface electrocordiogram. The electrograms are displayed on a storage oscilloscope with an automatic erase facility. This unit is used to locate accessory atriventricular connections in the Wolff-parkinson-White syndrome, to map ventricular tachycardias and to locate the bundle of His. The design has been refined during 5 years of use in over 200 operative procedures.  相似文献   
30.
Background: Very little is known about use of the class III antiarrhythmic dofetilide in patients with congenital heart disease (CHD).
Methods: A multicenter retrospective review of experience with dofetilide in CHD patients was undertaken.
Results: Twenty adults with CHD and refractory atrial arrhythmias were treated with dofetilide at four institutions over a 7-year period. Three (15%) experienced adverse effects during in-hospital initiation of dofetilide (two with torsade de pointes, one with excessive QTc prolongation) and were not continued on this therapy. The remaining 17 were discharged taking dofetilide, with either resolved or improved arrhythmia. One was lost to follow-up. Five subsequently discontinued dofetilide due to waning effectiveness, manifest by recurrence of their arrhythmias. Eleven (55%) remained on dofetilide at most recent visit, with a median follow-up of nearly 1 year. Seven of these 11, or 35% of the CHD patients originally started on dofetilide, experienced a complete resolution of their arrhythmia. The remaining four had breakthrough episodes of atrial arrhythmia, but remained on dofetilide. No patient experienced torsade de pointes after the in-hospital initiation period.
Conclusions: Used appropriately, dofetilide appears to be a viable adjunct to catheter-based ablation and alternative pharmacological approaches for the treatment of atrial arrhythmias in adult patients with congenital heart disease.  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