全文获取类型
收费全文 | 137443篇 |
免费 | 7308篇 |
国内免费 | 222篇 |
专业分类
耳鼻咽喉 | 2057篇 |
儿科学 | 5752篇 |
妇产科学 | 4553篇 |
基础医学 | 19531篇 |
口腔科学 | 3141篇 |
临床医学 | 10369篇 |
内科学 | 26023篇 |
皮肤病学 | 3902篇 |
神经病学 | 11174篇 |
特种医学 | 6141篇 |
外国民族医学 | 40篇 |
外科学 | 21998篇 |
综合类 | 1762篇 |
一般理论 | 40篇 |
预防医学 | 7266篇 |
眼科学 | 3895篇 |
药学 | 9516篇 |
中国医学 | 380篇 |
肿瘤学 | 7433篇 |
出版年
2019年 | 917篇 |
2018年 | 1267篇 |
2017年 | 1075篇 |
2016年 | 1504篇 |
2015年 | 1632篇 |
2014年 | 2106篇 |
2013年 | 2970篇 |
2012年 | 4093篇 |
2011年 | 4204篇 |
2010年 | 2533篇 |
2009年 | 2465篇 |
2008年 | 4100篇 |
2007年 | 4423篇 |
2006年 | 4586篇 |
2005年 | 4665篇 |
2004年 | 4538篇 |
2003年 | 4347篇 |
2002年 | 4280篇 |
2001年 | 7708篇 |
2000年 | 7581篇 |
1999年 | 6452篇 |
1998年 | 1874篇 |
1997年 | 1755篇 |
1996年 | 1506篇 |
1995年 | 1379篇 |
1994年 | 1239篇 |
1993年 | 1277篇 |
1992年 | 4102篇 |
1991年 | 3914篇 |
1990年 | 3941篇 |
1989年 | 3684篇 |
1988年 | 3293篇 |
1987年 | 3246篇 |
1986年 | 3112篇 |
1985年 | 2924篇 |
1984年 | 2180篇 |
1983年 | 1790篇 |
1982年 | 1061篇 |
1981年 | 1023篇 |
1979年 | 2055篇 |
1978年 | 1528篇 |
1977年 | 1277篇 |
1976年 | 1077篇 |
1975年 | 1323篇 |
1974年 | 1378篇 |
1973年 | 1362篇 |
1972年 | 1239篇 |
1971年 | 1144篇 |
1970年 | 1019篇 |
1969年 | 944篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
A. S. Mühlfeld M. Ketteler K. Schwamborn F. Eitner B. Schneider U. Gladziwa R. Knüchel J. Floege 《American journal of transplantation》2007,7(7):1865-1868
Sticky platelet syndrome (SPS) leads to hyperaggregabilty of platelets in response to physiologic stimuli. In this report we describe three patients with clinical symptoms of SPS after renal transplantation. The first patient developed an infarction of her transplant kidney with additional, subsequent renal microinfarctions. The second patient suffered multiple strokes and deep vein thrombosis with episodes of pulmonary embolism and ischemic bowel disease due to colonic microinfarctions. The third patient experienced a long episode of unexplained respiratory and graft dysfunction immediately after transplantation until therapy for SPS was initiated, at which point symptoms resolved quickly. Kidney transplant recipients with SPS may be at increased risk of developing thrombosis, given that most immunosuppressive drugs are known to induce either endothelial cell damage or augment platelet aggregation. All patients awaiting renal transplantation should be screened for a history of thrombosis and, if appropriate, tested for SPS. Affected patients should receive dose-adjusted acetylsalicylic acid. 相似文献
93.
94.
E S C Korf E C W van Straaten F-E de Leeuw W M van der Flier F Barkhof L Pantoni A M Basile D Inzitari T Erkinjuntti L-O Wahlund E Rostrup R Schmidt F Fazekas P Scheltens 《Diabetic medicine》2007,24(2):166-171
HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white matter hyperintensities. METHODS: In the Leukoaraiosis And DISability in the elderly (LADIS) study, we investigated the relationships between DM, hypertension, blood pressure and MTA in 582 subjects, stratified by white matter hyperintensity severity, using multinomial logistic regression. MTA was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95% CI: 1.1-7.8) compared with an MTA score of 0 (no atrophy). The odds ratio for MTA score 2 was not significantly increased (OR 1.8; CI: 0.9-4). Systolic and diastolic blood pressure and a history of hypertension were not associated with MTA. There was no interaction between DM and hypertension. Stratification on white matter hyperintensities (WMH) did not alter the associations. CONCLUSION: Our study strengthens the observation that MTA is associated with DM, independently of the amount of small vessel disease as reflected by WMH. 相似文献
95.
Beth T McCreary Thomas E Joiner Norman B Schmidt Nicholas S Ialongo 《Journal of clinical child and adolescent psychology》2004,33(2):313-324
This study examined the structure and symptom correlates of perfectionism in a sample of 6th-grade, urban, African American children using the Child and Adolescent Perfectionism Scale (CAPS; Flett, Hewitt, Boucher, Davidson, & Munro, 2000). Confirmatory factor analysis showed inadequate fit of the original subscales. Exploratory factor analysis suggested 3 dimensions of perfectionism: A Socially Prescribed and a Self-Oriented-Critical factor were described as maladaptive, whereas a Self-Oriented-Striving factor was proposed as adaptive. Cross-sectional correlations among the perfectionism dimensions and symptoms of psychopathology fit well with the adaptive versus maladaptive model. In addition, Socially Prescribed Perfectionism showed a robust predictive relation to 7th-grade internalizing symptoms, especially depression, in boys. Results are discussed in the context of the cultural and socioeconomic characteristics of this African American sample and suggestions for future research are provided. 相似文献
96.
Presented in this work is a rare injury of a blunt abdominal trauma in a child. Besides a partial rupture of the kidney and a retro-/intraperitoneal haematoma, a further injury occurred from the accident: an initially clinically indetectable tear of the A. iliaca communis which was found intraoperatively and with systematic CT analysis. Traumatic blood vessel lesions of the abdominal aorta and in particular the iliac blood vessels are very rare in children. By such violent impact injuries, it is therefore vital to perform a clinical examination of the foot pulse, systematic analysis of radiology diagnostics, and intraoperative exploration. The growth phase should be considered for therapy of the blood vessels depending on the child's age group. As the long-term results of graft implants are practically unknown, if possible a primary suture or vein patch should be performed. 相似文献
97.
98.
By oxygen concentration measurements (Oximeter Oxydig Dräger, Lübeck) in the EC 145 helicopter two oxygen transport and application systems were compared. The new liquid oxygen system (LOX) for the oxygen therapy was assessed in an application observation. For physical reasons fluid oxygen evaporates during the stand-by phase and an increased concentration (22.8% O2) in the exhaust valve of LOX arises. On the other hand a high oxygen concentration (22.7% O2) was measured in the operation mode of the conventional pressure flask gas system (GAS). No increased concentration could be measured within the helicopter cabin (HEMS, PAX) comparing both oxygen systems. For transport and application of oxygen with a very big reserve for the air dependent intensive transport the results show that LOX is a sure low pressure system (3.4 bar). 相似文献
99.
Objective To describe the clinical presentation of acute diverticulitis in an emergency department and to characterize the natural history of diverticulitis in the short perspective. Comparisons are made with an important differential diagnosis, nonspecific abdominal pain (NSAP). Method Patients admitted to our hospital with abdominal pain of up to 7 days’ duration were registered prospectively using a detailed schedule for history, symptoms and signs, from 1 February 1997 to 1 June 2000. Of 3349 patients initially included, 3073 (92%) were eligible for follow up after 1–3 years. Results Acute diverticulitis was the final diagnosis in 145 patients and NSAP in 1142 patients. The incidence of hospitalized patients with diverticulitis was 47 per year and 100 000 population, with a mean hospital stay of 3.3 days. Patients with diverticulitis, more frequently than NSAP, had a longer history and laboratory signs of inflammatory activity. Isolated left abdominal tenderness was more common in diverticulitis, whereas isolated right abdominal tenderness was more common in NSAP. Duration of symptoms on arrival was independent of age and was not correlated to C‐reactive protein, leucocytes or body temperature. Sensitivity of diverticulitis as primary diagnosis was 64% and specificity 97%. Corresponding figures for NSAP were 43% and 90% respectively. Age and gender did not influence diagnostic accuracy or risk of surgery. Conclusion Diverticulitis differs significantly from NSAP in clinical presentation and laboratory parameters. Sensitivity of primary diagnosis for diverticulitis and NSAP was low. 相似文献
100.
R Depprich J Handschel J Hornung U Meyer N R Kübler 《Mund-, Kiefer- und Gesichtschirurgie》2007,11(1):19-26
BACKGROUND: Fractures of the mandible are a common form of facial injury. The aetiological factors associated with mandibular fractures and the trends in these factors over a 10-year period are reported. METHODS: A retrospective survey was carried out of 724 patients presenting with a fracture of the mandible over the 10-year-period 1994-2003. Patients; records were reviewed and analyzed according to age, sex, cause of injury, anatomic site of fracture, treatment and postoperative complications. RESULTS: Over the 10-year-period the rate of mandibular fractures remained constant (mean 40,7%). There were no changes in the age group (mean 33,3 years) or in the higher prevalence in male (male-female-ratio 2,3 : 1). The major causes of fractures were assaults (38,6%) and accidental fall (27,3%). The most common fracture site was the condylar region (47,0%) followed by the angle (29,4%). Most fractures were treated by closed reduction until 2002, thereafter surgical treatment increased noticeable. The complication rate was 8,9% and the most common complications were hardware exposure and infection. CONCLUSION: Fractures of the mandible are a prevalent form of facial injury. Aetiological factors show no significant change over the 10-year-period. Complication-rate is low and will support the tendency towards surgical treatment. 相似文献