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   1315篇
  免费   58篇
  国内免费   11篇
耳鼻咽喉   28篇
儿科学   38篇
妇产科学   39篇
基础医学   122篇
口腔科学   20篇
临床医学   124篇
内科学   332篇
皮肤病学   18篇
神经病学   87篇
特种医学   83篇
外科学   267篇
综合类   22篇
预防医学   36篇
眼科学   47篇
药学   40篇
中国医学   2篇
肿瘤学   79篇
  2023年   8篇
  2022年   12篇
  2021年   24篇
  2020年   16篇
  2019年   25篇
  2018年   32篇
  2017年   26篇
  2016年   49篇
  2015年   51篇
  2014年   73篇
  2013年   90篇
  2012年   112篇
  2011年   101篇
  2010年   61篇
  2009年   41篇
  2008年   72篇
  2007年   76篇
  2006年   73篇
  2005年   62篇
  2004年   72篇
  2003年   55篇
  2002年   40篇
  2001年   26篇
  2000年   21篇
  1999年   12篇
  1998年   4篇
  1997年   10篇
  1996年   7篇
  1995年   4篇
  1994年   3篇
  1993年   3篇
  1992年   7篇
  1991年   3篇
  1990年   7篇
  1989年   13篇
  1988年   9篇
  1987年   12篇
  1986年   7篇
  1985年   9篇
  1984年   5篇
  1983年   6篇
  1978年   3篇
  1974年   6篇
  1971年   2篇
  1970年   7篇
  1969年   3篇
  1968年   2篇
  1967年   5篇
  1966年   2篇
  1965年   3篇
排序方式: 共有1384条查询结果,搜索用时 31 毫秒
1.
2.
Twenty-three patients (16 adults) failing their first or subsequent (n = 8) intensive treatment for de novo acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia lymphoid blast phase (n = 2) were managed with protocol POG 8201, originally introduced in relapsed ALL of childhood. In this programme, a four-drug induction phase is followed by early consolidation with teniposide-cytarabine, intrathecal chemotherapy, continuation weekly chemotherapy alternating teniposide-cytarabine with vincristine-cyclophosphamide, and periodic reinduction courses. Fourteen adults and five children with ALL achieved a complete response (CR) (86 per cent). The highest response rate (100 per cent) was obtained in 12 patients treated at first relapse after an initial CR of greater than 18 months (p = 0.07). Median duration of CR was 8 months in adults and 11 months in children. A longer than previous one CR (inversion) was obtained in four cases. Four ALL patients were successfully transplanted from a matched sibling after 3-11 months from achievement of CR. Median overall survival in adults with ALL was 11 months, significantly longer than for 40 comparable cases treated intensively but without rotational continuation therapy in previous years (p less than 0.001). This regimen is applicable to adults with relapsed ALL, where prolongation of survival may allow time for effective salvage with bone marrow transplantation.  相似文献   
3.
Angiotensin converting enzyme inhibitors (ACEI) are believed to protect remnant kidney, but all previous studies used the ligation model which causes severe hypertension, and very few have compared drugs in rats having similar control of blood pressure (BP). We compared rats with uremia obtained by 70% excision of total renal mass, a model which causes mild, late hypertension. Study I compared the effects of enalapril (E), cicletanine (C) and placebo (P) in uremic (U) rats fed a 0.50% (normal-high) Na diet. Study II compared the effects of E, C, P, and guanfacine (G) in U rats fed a diet restricted to 0.25% Na (normal-low). In study I, UP rats developed progressive hypertension (140, 146, 160 and 166 mm Hg at 3, 6, 9 and 12 weeks), proteinuria (240 mg/day at 9 and 12 weeks) which were not affected by E or C. The occurrence of end-stage renal disease (ESRD) led to the sacrifice of all rats after three months. All three groups had similar severe renal lesions (over 25% sclerosed glomeruli in 5 of 10 UP, 9 of 14 UE, 7 of 14 UC rats, with huge cystic tubular dilatations). In study II, rats could be sacrificed later (6 months) and had evidence of less severe renal disease. All the drugs tested prevented hypertension throughout the study (P less than 0.001), with lowest values in UE rats. E and G, but not C, reduced proteinuria. Renal damage was reduced with E and G, but not with C, despite similar BP in C and G rats. Thus, in contrast with what was obtained in the ligation model, ACEI affected neither the BP nor the renal lesions of rats made uremic by renal excision and fed a 0.50% Na diet. Moderate Na restriction improved the consequences of nephron loss and restored the anti-hypertensive effect of drugs. However, these drugs had a different effect on renal preservation: it was dramatic with E, good with G, and undetectable with C.  相似文献   
4.
5.
We have analyzed the distribution of aldolase A and C mRNAs and proteins in various areas of the human brain using Northern blot analyses and immunohistochemistry. Aldolase A mRNA expression was higher than aldolase C mRNA expression in all areas of the brain examined. Aldolase C mRNA expression was highest in the cerebellum. Aldolase C protein was present in well-delimited regions of the CNS, and was distributed in stripes in the Purkinje cell layer of the cerebellum, in the inferior olives and in the sensory neurons of the posterior horn of the spinal cord. The novel finding of aldolase C in well-delimited cell compartments of the human cerebellum and in several other areas of the CNS lends weight to the hypothesis that this protein exerts other functions (e.g. sensory transmission) besides those characteristic of a glycolytic enzyme.  相似文献   
6.
The case of a four-year-old boy is reported in whom the diagnosis of multiple cerebral and cerebellar focal tuberculous infections ("tuberculomas") was made. The diagnosis was based on a positive skin test, a history of contact, typical x-ray findings in the lung, CSF findings, and CT scan. The patient was treated during a three-year-period with antituberculous therapy. Sequential CT scans showed a relatively slow modification of the lesions, during a period of at least eighteen months, and thereafter their almost complete regression.  相似文献   
7.
Serum electrolyte equilibrium and plasma aldosterone concentrations were monitored in 19 infants who had severe obstructive uropathy or grade 5 vesico-ureteral reflux and were undergoing surgical correction in the first 2 months of life. Before surgery high plasma aldosterone levels were observed in 8 patients, but serum sodium and potassium concentrations were normal. Plasma concentrations of aldosterone were elevated in all patients during the week following surgery and 7 patients developed severe hyponatraemia, hyperkalaemia and weight loss despite very high plasma aldosterone concentrations. As a consequence 5 infants were infused with sodium chloride (4 mEq/kg per day) before and for 36h after surgery; this prevented metabolic imbalance. We conclude that infants undergoing surgical correction of uropathies may require a high sodium intake to maintain electrolyte balance and adequate growth.  相似文献   
8.
9.
10.
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle.  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