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   8793篇
  免费   914篇
  国内免费   607篇
耳鼻咽喉   67篇
儿科学   69篇
妇产科学   84篇
基础医学   968篇
口腔科学   126篇
临床医学   1241篇
内科学   1116篇
皮肤病学   98篇
神经病学   439篇
特种医学   311篇
外国民族医学   10篇
外科学   884篇
综合类   1642篇
现状与发展   9篇
预防医学   636篇
眼科学   316篇
药学   1034篇
  11篇
中国医学   537篇
肿瘤学   716篇
  2024年   34篇
  2023年   151篇
  2022年   413篇
  2021年   544篇
  2020年   405篇
  2019年   328篇
  2018年   301篇
  2017年   317篇
  2016年   284篇
  2015年   423篇
  2014年   544篇
  2013年   434篇
  2012年   667篇
  2011年   701篇
  2010年   407篇
  2009年   367篇
  2008年   419篇
  2007年   454篇
  2006年   370篇
  2005年   391篇
  2004年   291篇
  2003年   282篇
  2002年   272篇
  2001年   243篇
  2000年   233篇
  1999年   229篇
  1998年   103篇
  1997年   119篇
  1996年   81篇
  1995年   61篇
  1994年   59篇
  1993年   31篇
  1992年   50篇
  1991年   37篇
  1990年   24篇
  1989年   39篇
  1988年   28篇
  1987年   24篇
  1986年   23篇
  1985年   20篇
  1984年   10篇
  1983年   6篇
  1982年   6篇
  1975年   6篇
  1974年   7篇
  1973年   7篇
  1972年   11篇
  1971年   7篇
  1970年   9篇
  1968年   5篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
2.
ABSTRACT

Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group.

Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared.

Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group.

Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients.  相似文献   
3.
4.
5.
The objective of the present study was to evaluate the clinical, radiological, and functional outcomes of a subscapularis transthoracic surgical approach and a posterolateral surgical approach with debridement, bone graft fusion, and internal fixation for the treatment of upper thoracic tuberculosis.There is currently debate over the best surgical approach for the treatment of upper thoracic tuberculosis. Traditionally, the subscapularis transthoracic approach has been preferred; however, the posterolateral approach has gained popularity in the past few years.A prospective, consecutive cohort of 43 upper thoracic tuberculosis patients with a mean age of 39 years (range: 20–52 years) was followed up for a minimum of 12 months (range: 12–60 months). Patients were randomly divided into 2 groups. Group A (n = 21) was treated by the subscapularis transthoracic approach and group B (n = 22) was treated by the posterolateral approach. All cases were evaluated for clinical, radiological, and functional outcomes. Intraoperative blood loss, operative duration, intraoperative and postoperative complications, hospital stay, the cure rate, fusion time, and the Frankel scale were used for clinical and functional evaluation, whereas the kyphosis angle was used for radiological evaluation.Grafted bones were fused by 10 months in all cases. There was no statistically significant difference between groups before surgery in terms of gender, age, segmental tuberculosis, erythrocyte sedimentation rate (ESR), Frankel scale, or Cobb''s angle (P > 0.05). The average operative duration for Group B was lower than that of Group A. There were no significant differences in intraoperative blood loss, intraoperative and postoperative complications, hospital stay, grafted bone fusion time, or cure rate between groups (P > 0.05). The Cobb''s angle correction rate for group B (68.5%) was significantly better than that of group A (30.9%). The neurological score showed significant postoperative improvement in both groups, with no significant difference between the groups.The subscapularis transthoracic approach and the posterolateral approach with debridement, bone graft fusion, and internal fixation are both sufficient and satisfactory for the surgical treatment of upper thoracic tuberculosis. However, the posterolateral approach is superior to the subscapularis transthoracic approach in terms of surgical trauma, operative time, and kyphosis correction.  相似文献   
6.
BACKGROUND: Researches on diabetic nervous system lesion are mainly focus on peripheral nerve and vegetative nerve, so there are few investigations on diabetic pseudotabes. OBJECTIVE: To investigate the electrophysiological examinations on the diagnosis of diabetic pseudotabes. DESIGN: Case study. SETTING: Department of Electrophysiology and Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University. PARTICIPANTS: A total of 4 patients with type 2 diabetes mellitus, including 3 males and 1 female aged from 50 to 72 years, were selected from Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University from March 2002 to February 2005. All accepted subjects met the modified diagnostic criteria of diabetes mellitus, which was set by American Diabetes Mellitus Association (ADA) in 1997. Otherwise, the subjects had typical symptoms and physical signs of spinal posterior funiculus damage. However, patients with spinal cord lesion which was caused by other factors were excluded. All accepted subjects provided the confirmed consent. METHODS: Nicolet NT electromyography (EMG)/evoked potential meter (made in the USA) was used to detect spinal cord conduction velocity (SCCV), somatosensory evoked potential (SEP) of lower limbs, motor nerve conduction velocity (MNCV) and sensory nerve conduction velocity (SNCV) of extremities. Determining criteria: Measurements were performed based on the laboratory standards. SCCV, which was less than lower limit of normal value (T2–12: 40–55 m/s, T12–L4: 20–41 m/s, T2–L4: 36–45 m/s), was regarded as abnormal. SEP value of lower limbs: P40, P60 and PF, which were more than standard deviation of normal value (x(—)+2.5), were regarded as the abnormality. Normal value of P40, P60 and PF latencies (x(—)±s) in this study: P40, P60 and PF in males were (37.6±1.9) ms, (59.8±3.9) ms and (7.6±0.9) ms, respectively; meanwhile, those in females were (35.5±1.7) ms, (55.2±2.7) ms and (6.3±0.7) ms, respectively. MNCV and SNCV, which were less than 50 m/s in upper limbs and 40 m/s in lower limbs, were regarded as the abnormality. MAIN OUTCOME MEASURES: Electrophysiological examinations. RESULTS: All 4 patients with type 2 diabetes mellitus were involved in the final analysis. ① SCCV: Among 4 patients, SCCV of three patients was decreased in T2–12, T12–L4 and T2–L4, and that of the other one was decreased in T2–12 and T2–L4; however, SCCV in T12–L4 was normal. There was significant difference as compared with normal value (P < 0.01). ② SEP of lower limbs: SEP values of lower limbs were abnormal in all 4 patients. Among them, P40, P60 and PF latencies of two patients were delayed; P40 of one patient was delayed and PF was not drained out; P40 and P60 of the last one were delayed and PF was normal. ③ MNCV and SNCV: The MNCV and SNCV were normal in one patient and abnormal in three patients. The results demonstrated that MNCV and SNCV of extremities decreased; especially, sensory nerve action potential (SNAP) of both lower extremities of one patient were not drained out. CONCLUSION: Detections of SCCV, SEP of lower limbs, MNCV and SNCV of extremities are helpful to investigate whether peripheral nerve and deep sensory passage are damaged or not and determine whether deep sensory damage is caused by peripheral nerve and spinal posterior funiculus.  相似文献   
7.
中风毒邪论是一种与传统中医中风病理有所不同的理论 ,在中风毒邪论指导下形成解毒通络方是较为理想的神经保护剂 ,可解决目前神经保护治疗的主要障碍 ,有望成为提高中医治疗中风急性期疗效的关键  相似文献   
8.
取正常成人心脏瓣膜36个,置于低浓度广谱抗生素的营养液(RP-MI1640细胞培养液)中灭菌48h,-80℃冰箱初冻,置于液氮中长期保存。灭菌前后瓣膜细菌培养阴性率分别为94.3%和100%,解冻后经光镜、电镜检查证实瓣组织细胞结构正常,组织培养葡萄糖消耗率测定示瓣组织存活良好。临床同种心脏瓣膜原位移植3例,随访6~30个月,瓣功能良好  相似文献   
9.
卷柏抗肿瘤药理作用研究   总被引:16,自引:0,他引:16  
目的:为寻找高效低毒的抗肿瘤药物,探究卷柏抗肿瘤的药理作用。方法:采用卷柏水提物及其各个萃取部位对小鼠肉瘤S180,肝癌H22模型腹腔注射给药,并观察两肿瘤体重量变化。实验结果表明:卷柏水提取物及其各个萃取部位对两种瘤株均有不同程度的抑制作用,其中JB-W-2(水萃取部位)作用最强,且存在着剂量依赖性;其次是JB-W-3在大剂量时仅对肉瘤呈现较强的抑制作用。  相似文献   
10.
目的 提高肾嫌色细胞癌的诊治水平。方法 回顾性分析4例肾嫌色细胞癌患者的临床资料。男3例,女1例,年龄34—76岁,平均52岁。结果 3例患者行肾癌根治术,1例行肾部分切除术。术后病理诊断为肾嫌色细胞癌,病理分期:pT1aNxMo 1例,pT1bNoMo3例。病理分级:G1 3例,G2 1例。免疫组织化学染色:CK8(低分子量细胞角蛋白)阳性,Vimentin(波型蛋白)阴性,Hale胶体铁阳性。随访4个月至8年,平均4年。4例患者均健在,无肿瘤复发或转移。结论 肾嫌色细胞癌是一种低度恶性的肾细胞癌,影像学检查对其诊断有重要帮助,确诊有赖于组织病理学检查,手术治疗后预后较好。  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