首页 | 官方网站   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   151803篇
  免费   13432篇
  国内免费   9006篇
医药卫生   174241篇
  2024年   448篇
  2023年   2101篇
  2022年   5201篇
  2021年   6867篇
  2020年   5149篇
  2019年   4425篇
  2018年   4782篇
  2017年   4373篇
  2016年   4054篇
  2015年   6336篇
  2014年   8167篇
  2013年   7833篇
  2012年   11530篇
  2011年   12495篇
  2010年   8397篇
  2009年   6761篇
  2008年   8408篇
  2007年   8622篇
  2006年   8302篇
  2005年   8201篇
  2004年   5603篇
  2003年   5033篇
  2002年   4410篇
  2001年   3499篇
  2000年   3572篇
  1999年   3338篇
  1998年   1941篇
  1997年   1822篇
  1996年   1572篇
  1995年   1410篇
  1994年   1197篇
  1993年   741篇
  1992年   1168篇
  1991年   974篇
  1990年   823篇
  1989年   732篇
  1988年   694篇
  1987年   647篇
  1986年   518篇
  1985年   408篇
  1984年   267篇
  1983年   213篇
  1982年   114篇
  1981年   128篇
  1980年   117篇
  1979年   140篇
  1978年   79篇
  1977年   73篇
  1973年   65篇
  1972年   59篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
While balloon valvuloplasty has been widely used for the treatment of congenital valvular pulmonary stenosis (PS) in children and adults, its use in elderly patients is less common. An 80-year-old woman with congenital valvular PS received valvuloplasty with double-balloon technique. Right ventricle systolic pressure and pulmonary valve systolic pressure gradient decreased from 95 to 44 mm Hg and from 75 to 35 mm Hg, respectively. Follow-up Doppler echocardiography 2 months later showed further decrease in the transvalvular systolic pressure gradient to 29 mm Hg. The patient had symptomatic relief, and no major complication was noted. Balloon pulmonary valvuloplasty can be an effective treatment for elderly patients with congenital valvular PS.  相似文献   
32.
BACKGROUND AND PURPOSE: This study investigated the characteristics of intussusception in Taiwanese children of different age groups, including the incidence, length of hospitalization and hospital costs. METHODS: Children with a diagnosis of intussusception who were hospitalized from 1999 through 2001 were identified from a nationwide health insurance claims database. The incidence of intussusception was calculated by age, gender, and season. Length of hospitalization and hospital costs were also analyzed. RESULTS: A total of 6988 cases of intussusception were identified in Taiwan from 1999 to 2001. Among them, 4859 cases occurred in children below 15 years of age. The average incidence among children below age 15 years was 34.5 per 100,000, with a peak incidence of 118.8 per 100,000 observed among children younger than 24 months old. The highest incidence of intussusception in Taiwanese children occurred between 12 and 24 months of age. According to the data for patients below 15 years of age hospitalized for intussusception in year 2000, males were more likely to be affected than females (61.3% vs 38.7%). Intussusception-related hospitalizations were rare in infants in the first few months of life, increased in those 6 to 12 months old, and peaked among children 1 to 3 years old. Among the 952 patients with intussusception admitted to hospitals in 2000, 297 (31.2%) received surgery, incurring higher median medical costs (New Taiwan Dollars [NT dollars] 42,265 or US dollars 1234) and longer median hospital stay (6.2 days) than the 655 patients who did not require surgery (NT dollars 6290 or US dollars 185 for hospitalization of 2.4 days). CONCLUSIONS: The study found that the incidence of intussusception peaked in the second year of life in Taiwanese children. There was also a male predominance and lack of seasonal variation in incidence.  相似文献   
33.
X-linked hyper-immunoglobulin M (IgM) syndrome (XHIGM) is a rare genetic primary immunodeficiency disease caused by mutations of the CD40 ligand (CD40L) gene with normal or elevated levels of IgM and markedly decreased serum IgG, IgA, and IgE. Liver disease may occur as a clinical manifestation in XHIGM. This complication appears to increase with age. We report an 18-year-old male patient who had recurrent episodes of acalculous cholecystitis (AC) and sclerosing cholangitis (SC). The diagnosis of XHIGM was confirmed by the finding of CD40L expression < 1% of normal and a tyrosine 169 asparaginase (t526a) mutation in exon 5 (the tumor necrosis factor domain) of the CD40L gene. The patient had direct hyperbilirubinemia (direct bilirubin 5.5 mg/dL, total bilirubin 8.7 mg/dL), cholestasis (alkaline phosphatase 1133 U/L, gamma-glutamyl transferase 1019 U/L) and elevated transaminases (aspartate aminotransferase 70 U/L, alanine aminotransferase 101 U/L). Findings on abdominal ultrasound and abdominal computed tomography were compatible with AC. After the fourth episode of cholecystitis, cholecystectomy and liver biopsy were performed. Operative cholangiography revealed poor opacification of the hepatic duct and proximal common bile duct; the upstream intrahepatic bile ducts were not visualized. The biopsy specimen showed marked fibrosis of the portal areas. Enterococcus species was cultured from the bile. Children or adolescents with recurrent AC and SC should be evaluated for an underlying immunodeficiency syndrome such as XHIGM.  相似文献   
34.
Tumor metastasis to the pancreas is a rare but recognized cause of acute pancreatitis. Autopsy series have reported a 24-40% of pancreatic involvement in small cell lung cancer. However, only a very few cases of tumor-induced acute pancreatitis have been described. Budd-Chiari syndrome complicating lung cancer is a rarely reported condition. We report a 68-year-old woman with extensive small cell lung cancer with the unusual initial presentation of both acute pancreatitis and acute Budd-Chiari syndrome. This patient suffered from progressive epigastralgia for 3 weeks. Severe epigastralgia with radiation to back and progressive jaundice developed 2 days prior to admission. After admission, the liver enlarged rapidly and the ascites increased markedly. Chest roentgenogram showed a mass lesion over the left lower lung field. Poorly differentiated carcinoma cells were found in ascites and bone marrow. The patient died on the ninth day of hospitalization before chemotherapy was initiated. Prompt diagnosis of extensive-stage small cell lung cancer may allow early chemotherapy treatment which favorably influences recovery when the pancreatitis is mild. Although prolonged survival might have been expected had this patient recovered from pancreatitis and received chemotherapy, diagnosis was delayed due to difficulty in immunohistochemical diagnosis of the tumor and the unusual clinical presentation. The use of stains employing antibodies against neurofilament and neuron-specific enolase cell antigens is important for early diagnosis of poorly differentiated metastatic tumor cells.  相似文献   
35.
Pneumocephalus is a very rare complication of video-assisted thoracoscopic surgery (VATS). A 66-year-old man developed pneumocephalus secondary to thoracoscopic excision of a neurogenic tumor in the posterior mediastinum. Pneumocephalus was diagnosed by brain computed tomography. Neurosurgical intervention was performed after conservative therapy had failed. The patient's condition had resolved without any neurologic sequelae 2 years later. When a patient has a relatively large amount of chest tube drainage and neurologic symptoms after VATS, the possibility of pneumocephalus due to cerebrospinal fluid leakage must be considered.  相似文献   
36.
37.
Monoamine oxidase A gene promoter (MAOA-uVNTR) and catechol-O-methyltransferase V158M (COMT-V158M) gene functional polymorphisms are reported to be associated with impulsive-aggression, but a biological intermediate effect remains to be determined. This study assessed the association of these polymorphisms with cerebrospinal fluid (CSF) monoamine metabolites as endophenotypes. Ninety-eight Caucasian psychiatric subjects were assessed for Axis I and II diagnosis. Subjects were genotyped for the functional polymorphisms, MAOA-uVNTR and COMT-V158M. CSF was obtained by lumbar puncture. Relationships of the two polymorphism to monoamine metabolites: HVA, 5-HIAA, and MHPG were examined. The higher-expressing MAOA-uVNTR genotype was associated with higher CSF-HVA levels in males only (n = 46) (195.80 pmol/ml, SD = 61.64 vs. 161.13, SD = 50.23, respectively; P = 0.042). No association was found with diagnosis. COMT-V158M had no association with CSF monoamine metabolites. The association of MAOA-uVNTR with dopaminergic activity in males is a preliminary finding that needs to be replicated in a larger sample of Caucasian males and relationships sought with clinical phenotypes. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html.  相似文献   
38.
目的探讨硬膜外穿刺针外套管在腹腔镜小儿斜疝疝囊高位结扎中的应用价值。方法2003年4月-2006年5月,我院对230例小儿斜疝手术应用硬膜外穿刺针外套管代替雪橇钩针实施腹腔镜疝内环口荷包高位结扎术。结果230例手术均获得成功,手术时间:单侧161例8-10 min,嵌顿疝39例15-20 min,双侧30例16-20 min;术后未见有阴囊水肿及睾血疼痛及缺血坏死。术后随访2-6个月111例,6-12个月52例,12-24个月37例,24-36个月30例,无复发。结论硬膜外刺针外套管可替代小儿疝囊结扎专用的雪橇钩针,简便,经济,适合在所有基层医院推广。  相似文献   
39.
“黄风湿”系列疗法——火针封闭治疗痛风石的疗效观察   总被引:1,自引:0,他引:1  
痛风是一种由嘌呤代谢紊乱所致的疾病,日久不愈、反复发作则逐渐形成痛风石沉积。常规治疗对痛风石效果不明显。黄再军医院采用火针封闭疗法治疗痛风石36例,经临床观察治愈率为69.4%,显效率为25.0%,有效率为5.6%,总有效率达100%。  相似文献   
40.
支气管结核患者由于支气管局部的肉芽组织增生、溃疡、干酪性坏死、管腔狭窄阻塞等改变,虽然使用强有力的全身抗痨方案治疗,亦很难将其治愈,常常迁延不愈,局部结构组织破坏明显,引起永久性狭窄、闭塞,导致肺不张、毁损肺等严重的并发症。全身抗痨结合纤维支气管镜清理支气管局部的增生肉芽、坏死组织后注入异烟肼、链霉素的方法可使疗效明显提高。近年来微波技术已逐渐应用于通过纤维支气管镜治疗多种气道疾病。现将我院近5年来确诊的支气管结核用纤支镜局部病灶清理、注抗痨药治疗与同时联合微波热灼治疗的疗效进行分析、报告如下。  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-23

京公网安备 11010802026262号