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   63190篇
  免费   5514篇
  国内免费   2398篇
耳鼻咽喉   681篇
儿科学   770篇
妇产科学   1163篇
基础医学   9488篇
口腔科学   1536篇
临床医学   5691篇
内科学   11582篇
皮肤病学   1104篇
神经病学   4320篇
特种医学   2068篇
外国民族医学   13篇
外科学   8512篇
综合类   6193篇
现状与发展   3篇
一般理论   6篇
预防医学   3755篇
眼科学   1595篇
药学   5900篇
  6篇
中国医学   1471篇
肿瘤学   5245篇
  2023年   327篇
  2022年   705篇
  2021年   1040篇
  2020年   726篇
  2019年   1034篇
  2018年   1520篇
  2017年   1199篇
  2016年   1183篇
  2015年   1407篇
  2014年   1852篇
  2013年   2126篇
  2012年   2859篇
  2011年   2879篇
  2010年   1808篇
  2009年   1632篇
  2008年   2282篇
  2007年   2476篇
  2006年   2351篇
  2005年   1984篇
  2004年   1832篇
  2003年   1975篇
  2002年   1863篇
  2001年   5127篇
  2000年   4887篇
  1999年   4207篇
  1998年   1535篇
  1997年   1161篇
  1996年   727篇
  1995年   620篇
  1994年   558篇
  1993年   493篇
  1992年   2008篇
  1991年   1744篇
  1990年   1588篇
  1989年   1532篇
  1988年   1339篇
  1987年   1225篇
  1986年   1097篇
  1985年   920篇
  1984年   599篇
  1983年   472篇
  1982年   254篇
  1981年   184篇
  1980年   145篇
  1979年   289篇
  1978年   78篇
  1974年   75篇
  1973年   95篇
  1972年   71篇
  1969年   66篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
The authors reviewed the radiographic manifestations of 17 cases of parosteal osteosarcoma, with pathologic correlation in 15. There were two types of parosteal osteosarcoma radiologically. The majority of cases were type I with uniformly dense masses which had regular borders. They often adhered to the cortex and showed no evidence of soft-tissue invasion which correlated with low-grade pathologic malignancy and a relatively benign clinical course. Type II involved the bone, soft-tissue and the medullary cavity. These lesions were poorly differentiated and frequently accompanied by metastatic lesions.
  相似文献   
72.
73.
This paper is a summary of our observations on 105 cases of infantile spasms. The age of onset was around six months after birth, but the patients came for treatment mainly about one year after onset. Fever of unknown cause, asphyxia, birth injury, infection of the central nervous system, tuberous sclerosis, phenylketonuria and recent immunization etc. were complained. Clinically, it is characterized by head nodding, mental retardation, myoclonic jerks and various neurologic deficits. EEG findings showed classical or modified arrythmia or other epileptiform patterns. About one third of 22 cases examined had abnormal brain stem auditory evoked potentials. Among 42 patients who underwent CT scanning before ACTH treatment, 18 were normal and 7 abnormal; during ACTH treatment 3 normal and 4 abnormal; after completion of treatment, 4 normal and 6 abnormal, suggesting no further atrophy of the brain. Examination of trace elements of the hair by particle-induced X-ray emission (PIXE) method in 23 patients revealed a significant difference in lead, calcium and zinc contents between patients and 101 controls, but no statistical difference in iron and copper contents between the two groups. Sodium valproate, prednisone and ACTH appear to be effective in the treatment of infantile spasms. Eight patients fully recovered, and they can go to school without difficulty. Many patients derived various degrees of improvement to the satisfaction of their parents. Two patients were still amented and often attacked by myoclonus. The effects, side effects of these drugs, and the possible pathogenesis were discussed.
  相似文献   
74.
The effects of some antirheumatics on the formation and retraction of collagen lattices seeded with fibroblasts have been studied. Among the antirheumatics, diclofenac was the most active inhibitor of lattice retraction, then tropesin and to a lesser extent indomethacin. Ibuprofen which is known as a very slight inhibitor of protein synthesis was able to significantly enhance lattice retraction when 10 micrograms/ml (48.5 microM) and 50 micrograms/ml (242 microM) were used.  相似文献   
75.
目的:通过调查在校大学生对乙肝的认知程度,使其了解乙肝的传播途径,并针对由乙肝认知误区所引起的大学生乙肝歧视进行讨论,得出相应解决措施,积极创建和谐校园。方法:采用问卷调查的方式对在校的非医学生和医学生进行调查。结果:调查发现,很多大学生都对乙肝有了正确的认知态度,理解了与乙肝患者的平等性。相对较多的大学生对乙肝患者或是乙肝病毒携带者没有明显的生活上的排斥,但是心里仍存在一定的恐惧和歧视。结论:乙肝歧视仍存在于当代大学生之间,要使整个社会对乙肝歧视有所消除,大学生首当其冲要作好消除乙肝歧视,发展和谐校园,让乙肝歧视在校园中亮起红灯。  相似文献   
76.
77.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis.  相似文献   
78.
79.
目的 :探讨起搏器高度依赖性患者起搏器置换方法与疗效。 方法 :对 8例起搏器高度依赖性患者 ,在起搏器与电极的接口松解前 ,应用在体起搏器间断接触法 ,使自身逸搏心律得已恢复 ,然后再行松解接口以及必要的起搏参数测试。 结果 :起搏器离体次数为 3~ 7(5± 2 )次 ,最长逸搏间期为 3.38~ 6 .2 0 (4.5 1± 1.11)s,自身逸搏心率为 30~ 4 3(38± 5 )次 /min ,均顺利完成起搏器置换。 结论 :在体起搏器间断接触法切实可行 ,能够明显提高起搏器高度依赖性患者起搏器置换的安全性  相似文献   
80.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease.  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