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   50626篇
  免费   3033篇
  国内免费   489篇
耳鼻咽喉   670篇
儿科学   1835篇
妇产科学   859篇
基础医学   6589篇
口腔科学   1162篇
临床医学   3725篇
内科学   12007篇
皮肤病学   1671篇
神经病学   4090篇
特种医学   1270篇
外国民族医学   2篇
外科学   6323篇
综合类   1295篇
一般理论   16篇
预防医学   4314篇
眼科学   1470篇
药学   3450篇
  6篇
中国医学   529篇
肿瘤学   2865篇
  2024年   38篇
  2023年   381篇
  2022年   503篇
  2021年   1521篇
  2020年   809篇
  2019年   1532篇
  2018年   2190篇
  2017年   1351篇
  2016年   1204篇
  2015年   1218篇
  2014年   1530篇
  2013年   2261篇
  2012年   3809篇
  2011年   4202篇
  2010年   2132篇
  2009年   1396篇
  2008年   3204篇
  2007年   3212篇
  2006年   2928篇
  2005年   3032篇
  2004年   2761篇
  2003年   2642篇
  2002年   2417篇
  2001年   1625篇
  2000年   1985篇
  1999年   1193篇
  1998年   358篇
  1997年   248篇
  1996年   243篇
  1995年   219篇
  1994年   140篇
  1993年   154篇
  1992年   214篇
  1991年   174篇
  1990年   151篇
  1989年   151篇
  1988年   135篇
  1987年   117篇
  1986年   101篇
  1985年   94篇
  1984年   83篇
  1983年   60篇
  1982年   47篇
  1981年   37篇
  1980年   40篇
  1979年   27篇
  1978年   31篇
  1977年   28篇
  1976年   23篇
  1973年   23篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
通过对健康教育内涵的探讨 ,以研究健康教育的目的、任务和社会作用 ,进而确定其定义。实施健康教育重点是组织指导及健康教育的方法  相似文献   
52.

Background  

Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints.  相似文献   
53.
54.
PurposeTo analyze the electroclinical features, aetiology and outcome in patients with normal neurological examination and psychomotor development who presented seizures during a mild gastroenteritis (MG).Patients and methodsEvaluation of the clinical charts of 22 patients who were assessed in the Neurology Department, Hospital Nacional de Pediatría Prof. Dr. JP Garrahan between 1999 and 2007.ResultsTwelve patients were boys and 10 were girls, the age of onset ranged from 5 to 26 months, and the median age was 10 months. Rotavirus antigen test in stool was positive in 9 of 18 studied patients. The seizures were brief, focal with secondary generalization in 15 patients (68.5%), apparently generalized in 5 (22.5%) and focal in two (9%). Seven of the patients (35%) had more than one seizure in 24 h. The interictal EEG was normal in all patients. Neuroradiological studies were performed in 19 patients with a normal result. No patient was put on long-term treatment with antiepileptic drugs. Four patients had subsequent mild gastroenteritis and two of them presented convulsions during the disease. After between 12 and 67 months of follow-up, all patients had normal psychomotor development and neurological examination.ConclusionsIn this study we confirmed the association of benign infantile seizures (BIS) and MG with or without rotavirus. The identification of this entity allows avoiding unnecessary complementary studies and treatment with antiepileptic drugs.  相似文献   
55.
56.
57.
We review the association between surgically resolvable aortic disease and horseshoe kidney with a discussion of diagnostic problems and therapeutic options.Male patient 81 years of age with horseshoe kidney and an abdominal aortic aneurysm that was discovered by chance in an abdominal ultrasound during a check-up for his prostate condition.A retroperitoneal approach was used in order to resect the aneurysm and perform an aorto-aortic bypass with no complications occurring. Two years after the diagnosis, the patient is still asymptomatic from a vascular point of view.The co-presence of horseshoe kidney and aortic disease needing surgical correction is infrequent, but it significantly increases the technical complexity of aortic reconstruction. A literature review is included.  相似文献   
58.
PURPOSE: Temporomandibular joint (TMJ) arthroscopy has been considered a safe surgical procedure in the treatment of TMJ derangement. However, it is not exempt from complications. This study evaluates the complications of arthroscopy in patients with internal derangement of TMJ. PATIENTS AND METHODS: Five hundred consecutive patients (670 joints) with TMJ derangement who underwent arthroscopy between 1995 and 2004 were retrospectively analyzed. All the patients were classified as II to V in the Wilkes classification. Lysis and lavage, electrocautery of the posterior ligament, injection of corticoids, injection of ethanolamine, myotomy of lateral pterygoid muscle attachments, myotomy and electrocautery, motor debridement, injection of sodium hyaluronate, and meniscal suture were performed in different patients. RESULTS: Complications were recognized during or immediately after the surgery. They were observed in 5 of 341 (1.26%) arthroscopies of the right TMJ and 4 of 329 (1.21%) arthroscopies of the left TMJ. A 1.34% complication rate was found in the whole series. No blood clots within the external auditory canal were observed. Bleeding within the superior TMJ space was observed in 57 cases (8.5%), 36 of them in the right TMJ and 21 in the left TMJ, but they were not considered as true complications. Lacerations of the external auditory canal were found in 2 cases (0.3%), with no cases of perforation of the tympanic membrane. Lesion of the auriculotemporal nerve was observed in a case. Paresia of the facial nerve was found in 4 cases (0.6%). Alteration of visual accuracy of the ipsilateral eye was also observed in a patient immediately after the surgery. CONCLUSION: Special care must be taken to reduce complications within the upper joint space by means of an adequate instrumentation and by paying attention to essential points of the arthroscopic technique.  相似文献   
59.
The ability of acetaldehyde to generate free radicals is often ascribed to its oxidation by xanthine oxidase, with the subsequent production of reactive oxygen intermediates. Chemiluminescence associated with the oxidation of acetaldehyde by xanthine oxidase was inhibited by superoxide dismutase, catalase, or several hydroxyl radical scavenging agents, and was stimulated by the addition of EDTA or ferric-EDTA. This suggests that the light emission is primarily due to the production of hydroxyl radicals via an iron-catalyzed Haber-Weiss type of reaction. Chemiluminescence with hypoxanthine as substrate for xanthine oxidase was much lower than that found with acetaldehyde, yet rates of hydroxyl radical production were greater with hypoxanthine. Acetaldehyde increased light emission in the presence of hypoxanthine by a greater than additive effect. These results suggest a complex role for acetaldehyde in catalyzing xanthine oxidase-dependent chemiluminescence. It appears that besides being a substrate for xanthine oxidase, acetaldehyde also reacts with the generated hydroxyl radical to produce acetaldehyde radicals, which yield chemiluminescence upon their decay. Further studies will be required to evaluate whether the production of such species contributes to or plays a role in the generation of reactive oxygen intermediates and toxicity associated with acetaldehyde metabolism.  相似文献   
60.
Abstract Background and study aims: The advent of endoscopic techniques in the last decades has produced a change in the approach of the oesophageal leiomyoma. The aim of the study is to explain our experience in the laparoscopic surgery of the oesophageal leiomyoma. Materials and methods: We realised a retrospective study of the oesophageal leiomyoma operated on in our centre by the endoscopic approach between 2001 and 2004. There were two females and two males. All were symptomatic and pyrosis was the most frequent symptom. The preoperative study was an oral endoscopy and barium swallow. In all the cases enucleation was performed, two by thoracoscopy and two by laparoscopy approach. Results: The mean operating time was 230 min. No deaths or intraoperative complications occurred and there were no cases of conversion to open surgery either. The mean postoperative hospital stay was 3.25 days (range 2–4 days). There was no case of recurrence. Conclusions: The enucleation is an easier procedure and constitutes the therapy of choice of the oesophageal leiomyoma. We think that muscle borders should be closed after enucleation and that biopsy is not indicated preoperatively.  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