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   22803篇
  免费   1572篇
  国内免费   524篇
耳鼻咽喉   542篇
儿科学   573篇
妇产科学   1235篇
基础医学   628篇
口腔科学   529篇
临床医学   2354篇
内科学   3684篇
皮肤病学   133篇
神经病学   1209篇
特种医学   511篇
外国民族医学   2篇
外科学   7274篇
综合类   2394篇
现状与发展   2篇
预防医学   884篇
眼科学   736篇
药学   932篇
  87篇
中国医学   408篇
肿瘤学   782篇
  2024年   60篇
  2023年   498篇
  2022年   812篇
  2021年   1212篇
  2020年   1189篇
  2019年   991篇
  2018年   929篇
  2017年   849篇
  2016年   782篇
  2015年   795篇
  2014年   1514篇
  2013年   1533篇
  2012年   1074篇
  2011年   1241篇
  2010年   1056篇
  2009年   1002篇
  2008年   1035篇
  2007年   994篇
  2006年   928篇
  2005年   817篇
  2004年   725篇
  2003年   661篇
  2002年   503篇
  2001年   486篇
  2000年   315篇
  1999年   289篇
  1998年   270篇
  1997年   252篇
  1996年   206篇
  1995年   162篇
  1994年   174篇
  1993年   163篇
  1992年   161篇
  1991年   128篇
  1990年   110篇
  1989年   108篇
  1988年   104篇
  1987年   93篇
  1986年   56篇
  1985年   102篇
  1984年   92篇
  1983年   60篇
  1982年   70篇
  1981年   68篇
  1980年   53篇
  1979年   47篇
  1978年   33篇
  1977年   36篇
  1976年   23篇
  1975年   18篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
71.
A single observer reviewed 842 of the 917 known diabetic patients registered with 40 GPs in the Poole area. Fifty-nine per cent (493) of those reviewed submitted a timed overnight urine collection to measure albumin excretion rate (AER) and overnight albumin/creatinine ratio (ON-Alb/Creat); 43 samples were excluded because of urinary tract infection and/or proteinuria. A random urine sample was obtained in 607 diabetic patients to measure the random albumin/creatinine ratio (R-Alb/Creat); 68 specimens were excluded because of infection and/or proteinuria, and in a further 10 samples urinary creatinine was not measured. Stepwise multiple regression analyses found significant associations with the following variables: for AER, blood glucose (p = 0.001), smoking category (p = 0.002), sex (p = 0.034), and systolic blood pressure (p = 0.035); for R-Alb/Creat, blood glucose (p = 0.001), retinopathy (p = 0.004), systolic blood pressure (p = 0.004), diastolic blood pressure (p = 0.015), coronary artery disease (p = 0.02), sex (p = 0.034), and vibration sense (p = 0.038). Interestingly, glycosylated haemoglobin was not a significant determinant of albuminuria in either analysis.  相似文献   
72.
妊娠合并急性阑尾炎的临床特点   总被引:1,自引:0,他引:1  
报告妊娠期急性阑尾炎31例,占急性阑尾炎的063%,占女性急性阑尾炎的156%。手术治疗58%。阑尾穿孔226%,其中完全流产、先兆流产、低位肠瘘各32%。本病特点为:早期:症状、体征与一般病人相似,但恶心、呕吐易被误认为是妊娠反应;中期:疼痛和压痛部位向上向内移位;晚期:腹痛和压痛位于右上腹或右侧腹部,易被误认为子宫收缩痛。本病炎症容易播散,可发生早产、流产或孕妇死亡。应早期确诊,及时手术。  相似文献   
73.
A critically important aspect of supportive care in cancer is the prompt recognition and effective treatment of psychiatric complications. Psychiatric disorders such as depression, anxiety and delirium occur in a signifcant percentage of cancer patients, particularly as disease advances and as cancer treatments become more aggressive. This paper reviews factors that can be utilized to identify patients who are at increased risk for developing psychiatric complications, such as those with advanced disease, certain cancer treatments, uncontrolled physical symptoms, functional limitations, lack of social support, and past history of psychiatric disorder. Methods of diagnostic assessment and strategies for managing depression, anxiety, delirium and suicidal ideation are also reviewed.Presented as an invited lecture at the 6th International Symposium: Supportive Care in Cancer, New Orleans, La., USA, 2–5 March 1994  相似文献   
74.
Summary One hundred patients with a verified subarachnoid haemorrhage were studied in a double blind, placebo-controlled trial at a single centre to determine the value and relative risks of tranexamic acid (TXA) in the management of ruptured intracranial aneurysms. The incidence of recurrent haemorrhage between active and placebo groups was identical (12%) and the mortality from recurrent haemorrhage was 7% and 5%, respectively. The overall incidence of cerebral infarction before surgery, at discharge and at 6 months follow-up was greater in the TXA group (27%) than in the control group (11%). Post-operative cerebral ischaemia was significantly more frequent in the active, 18 of 29 as compared to 6 of 32 patients, in the placebo group. In a fifth of the patients in whom cerebral blood flow was estimated there was a significant reduction of cerebral blood flow (CBF) on the side of the ruptured aneurysm in the TXA treated group. It is suggested that this may be the cause of the increased incidence of cerebral ischaemia in this group. There was no significant difference in the incidence of cerebral vasospasm, hydrocephalus, visual disturbances and gastrointestinal disturbances.More fatalities were encountered from ischaemia and recurrent haemorrhage in the TXA group but these differences did not reach statistical significance at the 5% level. Given that disability was due to either vasospasm or recurrent haemorrhage then a patient under TXA treatment was significantly more likely to have disability due to vasospasm (p<0.04); the reverse was true for the placebo patient (p<0.05).  相似文献   
75.
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07).  相似文献   
76.
This study investigated the relationship between the development of diabetic retinopathy and pubertal status at onset of diabetes in 521 Type 1 diabetic patients diagnosed between 1950 and 1985. Pubertal status was based on age at onset (girls ≧ 11 years and boys ≧ 12 years). Retinopathy (all forms) developed in 112 patients (21.5%; 65 background and 47 proliferative retinopathy). For subjects diagnosed in either the prepubertal or postpuberal period, a similar proportion survived without developing retinopathy for any given duration of diabetes (X2 = 0.3822, p = 0.54). However, if only the postpubertal duration of diabetes is considered, then the proportion of patients surviving without retinopathy was significantly less for those diagnosed in the prepubertal period (X2 = 14.2, p = 0.002). This study suggests that the prepubertal duration of diabetes is an important phase and that the years prior to puberty do contribute to the risk of developing microvascular injury.  相似文献   
77.
妇科恶性肿瘤术后骨质疏松症的防治   总被引:1,自引:0,他引:1  
王焱  金健  刘晓红 《中医正骨》2005,17(11):10-11
为探讨妇科恶性肿瘤术后骨质疏松症的预防措施,采用补充紫竹爱维和乐力胶囊来预防骨质疏松的发生,分别与未服药的妇科恶性肿瘤及良性肿瘤术后作对照,并对其对骨代谢指标血清骨性碱性磷酸酶(BALP)及血清抗酒石酸酸性磷酸酶(TRAP)的影响进行了临床观察.结果发现恶性肿瘤术后较良性肿瘤术后患者的BALP降低,TRAP增高,服用紫竹爱维与乐力胶囊的患者TRAP均低于未服药的恶性肿瘤术后患者,P<0.05,均有显著性差异.表明妇科恶性肿瘤术后患者较良性肿瘤更易患骨质疏松症,服用紫竹爱维与乐力胶囊均能有效防治骨质疏松症,前者效果更佳,但应掌握性激素补充治疗(HRT)的应用指征.  相似文献   
78.
Zusammenfassung Über ein Jahr wurden 1082 allgemeinchirurgische Planeingriffe prospektiv konsekutiv erfaßt und ihre Komplikationen mit einem Score bewertet. EinflußgröBen und die Komplikationsraten, die unter Umständen von der Kliniks-organisation abhängig sind, sollten analysiert werden. Es fand sich eine Beziehung zwischen Komplikationen und Wochentag, Operationsdauer sowie der Abweichung der tatsächlich benötigten von der geplanten Operationszeit. Mit höherer Auslastung der Operationssäle pro Arbeitstag stiegen die Komplikationsraten ebenfalls an.Keinen Einfluß auf die Komplikationsraten hatten Operationsbeginn und-monat sowie die monatliche Auslastung der Säle. Ob das Wetter einen Einfluß auf die Komplikationsraten nahm, konnte nicht entschieden werden: so fanden sich im Sommer- höhere Komplikationsraten als im Winterhalbjahr, jedoch war der Score von der Höhe der Außentemperatur und der Luftfeuchtigkeit unabhängig.
The influence of time of operation and hospital organization on postoperative complication rates
Summary During a 1-year period 1082 general surgical interventions were prospectively documented and their complication rates evaluated by a score system. Factors responsible for the complication rates and possibly depending on hospital organization should be analysed. The complication rates were influenced by the selection of the weekday, the length of operation time and the extent of discrepancy between planned and required operation time. Furthermore, the complication rates paralleled the extent of utilization of the operation theatre during a workday. The complication rates werenot affected by the beginning of operation and the operation month as well as the monthly utilization of the operation theatres. Whether the weather did influence the complication rates could not be decided: higher complication rates were found in the summer as compared to the winter period, but the complication score was independent of the level of the outside temperature and humidity.
  相似文献   
79.
Summary Determinations of mononuclear cell subsets in cerebrospinal fluid (CSF), using monoclonal antibodies against surface antigens which identified pan T-cells, helper/inducer T-cells, cytotoxic/suppressor T-cells and Ia-positive cells, were performed in patients with multiple sclerosis (MS), other neuroimmunological diseases (NID), infectious diseases (INF) of the central nervous system and with other neurological diseases. Whereas there was an elevated helper T/suppressor T ratio in CSF of patients with NID (Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, cerebral vasculitis), no other significant differences could be detected between the different groups of patients. Our results suggest that analysis of these mononuclear cell subsets in CSF is not helpful in discriminating between MS and other neurological diseases and that in MS patients changes in disease activity are not clearly indicated by fluctuations in the different CSF cell subsets. Further studies will be needed to confirm our findings in NID patients and to understand the diagnostic and theoretical implications.  相似文献   
80.
目的 :评价原发性肝癌并发门静脉高压症的外科治疗效果。方法 :回顾性分析联合手术治疗原发性肝癌并发门静脉高压症 30例的疗效。结果 :手术死亡 1例 ,严重肺部感染、肝肾综合征及顽固性腹水各 1例。术后 1、3、5年生存率分别为 93.3%、5 3.3%、40 %。随访中共死亡 1 7例 ,死亡原因 :肝癌复发 9例 ,肝功能衰竭 5例 ,上消化道出血 3例。结论 :理性选择联合手术方式治疗原发性肝癌并发门静脉高压症是安全可行的 ,联合行胃冠状静脉栓塞和脾切除术效果良好。  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