全文获取类型
收费全文 | 522495篇 |
免费 | 34129篇 |
国内免费 | 655篇 |
专业分类
耳鼻咽喉 | 7001篇 |
儿科学 | 17120篇 |
妇产科学 | 13727篇 |
基础医学 | 86321篇 |
口腔科学 | 14711篇 |
临床医学 | 45068篇 |
内科学 | 95509篇 |
皮肤病学 | 12374篇 |
神经病学 | 37063篇 |
特种医学 | 18720篇 |
外国民族医学 | 64篇 |
外科学 | 78246篇 |
综合类 | 8514篇 |
一般理论 | 119篇 |
预防医学 | 39630篇 |
眼科学 | 12258篇 |
药学 | 41114篇 |
中国医学 | 1022篇 |
肿瘤学 | 28698篇 |
出版年
2018年 | 5208篇 |
2016年 | 4280篇 |
2015年 | 4737篇 |
2014年 | 6347篇 |
2013年 | 9929篇 |
2012年 | 13376篇 |
2011年 | 14771篇 |
2010年 | 8604篇 |
2009年 | 8006篇 |
2008年 | 14085篇 |
2007年 | 15103篇 |
2006年 | 15361篇 |
2005年 | 14732篇 |
2004年 | 14404篇 |
2003年 | 13678篇 |
2002年 | 13575篇 |
2001年 | 24343篇 |
2000年 | 25346篇 |
1999年 | 20776篇 |
1998年 | 5510篇 |
1997年 | 4793篇 |
1996年 | 5117篇 |
1995年 | 4707篇 |
1994年 | 4380篇 |
1992年 | 15915篇 |
1991年 | 16469篇 |
1990年 | 16568篇 |
1989年 | 15941篇 |
1988年 | 14708篇 |
1987年 | 14518篇 |
1986年 | 13693篇 |
1985年 | 13070篇 |
1984年 | 9710篇 |
1983年 | 8306篇 |
1982年 | 4595篇 |
1981年 | 4253篇 |
1979年 | 9475篇 |
1978年 | 6884篇 |
1977年 | 5798篇 |
1976年 | 5628篇 |
1975年 | 6420篇 |
1974年 | 7669篇 |
1973年 | 7164篇 |
1972年 | 6981篇 |
1971年 | 6711篇 |
1970年 | 6197篇 |
1969年 | 5909篇 |
1968年 | 5578篇 |
1967年 | 5026篇 |
1966年 | 4475篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Intraoperative cholangiography revisited. 总被引:2,自引:0,他引:2
B W Pace J Cosgrove B Breuer I B Margolis 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(4):448-450
The charts of 1351 patients undergoing cholecystectomy at our institutions from 1985 through 1989 were reviewed retrospectively to evaluate the indications for and the success of intraoperative cholangiography. A total of 800 patients underwent intraoperative cholangiography. They were divided into two groups based on the absence (CR-) or presence (CR+) of clinical and/or operative criteria suggestive of the existence of common bile duct stones. Intraoperative cholangiography in CR- patients was of limited benefit, being negative (normal) in 95.7%, true-positive (abnormal) in 3.3%, and false-positive in 1%. False-positive intraoperative cholangiography resulted in unnecessary common bile duct explorations. Intraoperative cholangiography in CR+ patients proved useful, avoiding unnecessary common bile duct exploration in 55%. In those select CR+ patients with palpable common bile duct stones or cholangitis, little additional information was gained by the intraoperative cholangiography. We conclude that routine screening intraoperative cholangiography in CR- patients be reconsidered, as should the use of intraoperative cholangiography in CR+ patients with a palpable common bile duct stone or cholangitis. Intraoperative cholangiography in the remainder of CR+ patients proved beneficial and should be continued. 相似文献
992.
A study of the longterm efficacy and toxicity of cyclosporine A in rheumatoid arthritis. 总被引:1,自引:0,他引:1
We determined the longterm efficacy and toxicity of cyclosporine A in rheumatoid arthritis (RA) in an open clinical trial, at a single centre, outpatient rheumatology clinic. The initial dose was 5 mg/kg/day increased to 10 mg/kg/day with adjustments for toxicity and plasma cyclosporine A levels. We measured efficacy by the Ritchie articular index, pain and function on a 10 cm visual analog scale, C-reactive protein (CRP) and erythrocyte sedimentation rate. Toxicity was evaluated by patient reports, serum creatinine, cyclosporine A levels and liver function tests. Median treatment duration was 29 months (16.5-38). At 24 months median reduction in Ritchie articular index was 50% (9-79); pain: 49% (21-77), with a 50% (4-76) improvement in function; and CRP fell by 72.5% (22-87). The main side effect was a 40% (27-47) decline in estimated creatinine clearance. We conclude that cyclosporine A at doses below 5 mg/kg/day is associated with clinically significant improvements in indices of disease activity in RA. Renal dysfunction was the most frequent side effect. 相似文献
993.
F Armellini M Zamboni L Rigo I A Bergamo-Andreis R Robbi M De Marchi O Bosello 《International journal of obesity (2005)》1991,15(12):847-852
The aim of this study was to check the reliability of sonography in measuring small variations in quantities of subcutaneous and intra-abdominal fat. Twenty-six obese women (BMI 39 +/- 6) underwent a 15 day very low calorie diet. The study included, both before and after very low calorie diet, computed tomography measurements of total (AT), visceral (VAT) and subcutaneous (SAT) adipose tissue areas, visceral/subcutaneous area ratio (V/S), waist/hip circumference ratio measurements (W/H), and ultrasound measurements of abdominal subcutaneous skin-muscle thickness, intra-abdominal muscle-aorta thickness and intra-abdominal/subcutaneous thickness ratio. Weight reduction was from 101 +/- 17 to 95 +/- 16 kg (P less than 0.001). W/H dropped from 0.83 +/- 0.06 to 0.82 +/- 0.07 (n.s.). VAT dropped from 158 +/- 72 to 134 +/- 61 cm2 (P less than 0.005), SAT from 572 +/- 151 to 566 +/- 164 cm2 (n.s.) and V/S from 0.29 +/- 0.15 to 0.25 +/- 0.11 (P less than 0.01). Abdominal subcutaneous fat thickness decreased from 36 +/- 8 to 35 +/- 10 mm (n.s.), intra-abdominal thickness from 39 +/- 25 to 20 +/- 20 mm (P less than 0.001) and intra-abdominal/subcutaneous from 1.1 +/- 0.7 to 0.8 +/- 0.6 (P less than 0.005). VAT measurement accurately identified small intra-abdominal fat variations. W/H could not evaluate visceral fat loss, because of simultaneous decreases in waist and hip circumferences. Ultrasound was able to measure small reductions in intra-abdominal fat. 相似文献
994.
Prodromal frontal/executive dysfunction predicts incident dementia in Parkinson's disease. 总被引:2,自引:0,他引:2
Steven Paul Woods Alexander I Tr?ster 《Journal of the International Neuropsychological Society》2003,9(1):17-24
To identify the cognitive characteristics predictive of incident dementia in Parkinson's disease (PD), we examined the baseline neuropsychological profiles of 18 initially non-demented patients with PD who met diagnostic criteria for dementia (PDD) at one-year follow-up. PDD participants' baseline neuropsychological test scores were compared to the baseline performance of 18 patients with PD who did not meet criteria for dementia at one-year follow-up (PDND) and 18 normal controls (NC). The three groups were matched on baseline demographic and disease variables. Relative to the PDND group, the incident PDD participants demonstrated significantly poorer performance on digits backward (Wechsler Memory Scale-Revised), word list learning and recognition (California Verbal Learning Test), and perseverative errors on the Wisconsin Card Sorting Test. Each of these baseline neuropsychological variables exhibited adequate diagnostic classification accuracy in predicting PDD and PDND group membership at follow-up. These results suggest that subtle frontal/executive dysfunction is evident during the immediate PDD prodrome and may be of prognostic value in identifying PD patients at risk for dementia. Accordingly, neuropsychological evaluation may facilitate early identification of PDD and thereby inform appropriate dispositional planning. 相似文献
995.
The natural killing of K 562 cells by whole blood from normal subjects was comparable with that shown by separated mononuclear cells. In order to establish the conditions for a reliable natural killer assay by using very small numbers of effector cells in whole blood, the isotope uptake of target cells was increased by a modified labelling method, which permitted the use of fewer target cells in the assay. The natural cytotoxicity of whole blood was augmented by interferon to the same extent as observed with separated mononuclear cells. The chemiluminescence of granulocytes in whole blood comparable with that of separated granulocytes. Taken together, these methods are considerably less tedious than the conventional methods, technique is also economical, and the results may reflect in vivo cytolytic processes much better. 相似文献
996.
I Matsubara Y Naruse S Sokejima T Yamagami S Kagamimori 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1992,39(11):873-878
A data system which enables utilization of individual patient data by public health nurses, physicians and home helpers, is required both for the continuous and comprehensive monitoring of the various needs of the aged receiving care services at home in the local district and for facilitating welfare services. Therefore, an experimental and comprehensive system for public health, medical services and welfare was put into practice for district public health services for the aging society. The results of this trial system shows that this system is useful indeed for the welfare services, though it also has several problems. 相似文献
997.
Moscow Scientific Research Institute of Roentgenoradiology. Translated from Meditsinskaya Tekhnika, No. 2, pp. 6–8, March–April, 1992. 相似文献
998.
In the fasting state, antral motor activity is similar in preterm and term infants, but the antral responses to feeding have not been compared in preterm and term infants. The purpose of this study was to use low-compliance, continuous perfusion manometry to compare antral and duodenal feeding responses in 13 preterm and nine term infants within the first 14 days of life. Confirming our previous studies, fasting antral motor activity was similar in preterm and term infants, but duodenal activity differed. Individual duodenal cluster activity was of shorter duration in preterm than in term infants (p less than 0.01). Motor activity in antrum and duodenum changed in both groups of infants in response to an intraduodenal milk infusion of 4 ml/kg/2 h; however, the nature of the change varied in the two regions. In term infants, the number of antral pressure waves, the duration of antral clusters, and the antral motility index decreased by one third or more during feeding when compared with fasting (all p less than 0.05). In contrast to the decrease in antral activity in response to feeding, the duodenal motility index and cluster activity increased significantly during feeding compared with fasting (both p less than 0.05). The divergent response of antral and duodenal motor activity in response to feedings was also seen in preterm infants. Antral pressure waves, the duration of antral clusters, and the antral motility index were decreased during feeding (all p less than 0.005 or less).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
1000.