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   426篇
  免费   34篇
  国内免费   2篇
儿科学   15篇
妇产科学   8篇
基础医学   39篇
口腔科学   3篇
临床医学   41篇
内科学   85篇
皮肤病学   10篇
神经病学   43篇
特种医学   40篇
外科学   53篇
综合类   8篇
一般理论   1篇
预防医学   35篇
眼科学   4篇
药学   31篇
肿瘤学   46篇
  2021年   11篇
  2020年   5篇
  2019年   7篇
  2018年   10篇
  2017年   2篇
  2016年   3篇
  2015年   11篇
  2014年   12篇
  2013年   21篇
  2012年   27篇
  2011年   27篇
  2010年   17篇
  2009年   12篇
  2008年   26篇
  2007年   16篇
  2006年   18篇
  2005年   23篇
  2004年   21篇
  2003年   16篇
  2002年   17篇
  2001年   9篇
  2000年   9篇
  1999年   9篇
  1998年   9篇
  1997年   7篇
  1996年   2篇
  1995年   7篇
  1994年   3篇
  1993年   5篇
  1992年   8篇
  1991年   9篇
  1990年   10篇
  1989年   4篇
  1988年   3篇
  1987年   6篇
  1986年   2篇
  1985年   4篇
  1984年   7篇
  1983年   7篇
  1982年   2篇
  1981年   3篇
  1979年   3篇
  1978年   4篇
  1977年   3篇
  1976年   5篇
  1974年   2篇
  1972年   4篇
  1971年   2篇
  1967年   3篇
  1966年   3篇
排序方式: 共有462条查询结果,搜索用时 13 毫秒
1.
2.
OBJECTIVE: This phase II trial assessed the feasibility, as measured by response rate, toxicity, resectability rate, and surgical morbidity and mortality rates, of perioperative paclitaxel and carboplatin chemotherapy in patients with early-stage non-small cell lung carcinoma. METHODS: All patients required negative mediastinoscopy results and adequate medical parameters to undergo induction chemotherapy and an operation. Superior sulcus patients were excluded. Chemotherapy consisted of paclitaxel 225 mg/m(2) over 3 hours and carboplatin (area under the curve = 6) every 21 days for 2 cycles preoperatively. Three postoperative cycles of chemotherapy were planned for patients undergoing complete resection. RESULTS: Between June 1996 and July 1998, 94 patients were entered into the study. Sixty-five (69%) were men, and the median age was 64 years (range, 34-79 years). After induction chemotherapy, 53 of 94 (56%; 95% confidence interval, 46%-67%) had a major objective response, 88 (94%) underwent surgical exploration, and 81 (86%; 95% confidence interval, 78%-92%) underwent complete resection. Reasons for not undergoing an operation included disease progression (n = 3), clinically unresectable status (n = 1), death (n = 1), and patient lost to follow-up (n = 1). Two postoperative deaths occurred. Six (6%; 95% confidence interval, 0%-13%) pathologic complete responses were observed. Ninety (96%) patients received the planned preoperative chemotherapy versus 45% receiving postoperative chemotherapy. No unexpected chemotherapy or surgical morbidity occurred. The 1-year survival is currently estimated at 85%, and the median survival has not yet been reached. CONCLUSIONS: Induction chemotherapy with paclitaxel and carboplatin is feasible and produces a high response rate with acceptable morbidity and mortality rates in early-stage non-small cell lung carcinoma. A prospective randomized trial comparing 3 cycles of induction chemotherapy and surgery with surgery alone in early-stage non-small cell lung carcinoma is planned.  相似文献   
3.
Infants born preterm are at a higher risk of complications and hospitalization in cases of rotavirus diarrhea than children born at term. We evaluated the impact of a rotavirus vaccination campaign (May 2007 to May 2010) on hospitalizations for rotavirus gastroenteritis in a population of children under 3 years old born prematurely (before 37 weeks of gestation) in the Brest University Hospital birth zone. Active surveillance from 2002 to 2006 and a prospective collection of hospitalizations for rotavirus diarrhea were initiated in the pediatric units of Brest University Hospital until May 2010. Numbers of hospitalizations for rotavirus diarrhea among the population of children born prematurely, before and after the start of the vaccination program, were compared using a Poisson regression model controlling for epidemic-to-epidemic variation. A total of 217 premature infants were vaccinated from 2007 to 2010. Vaccine coverage for a complete course of three doses was 41.9%. The vaccine safety in premature infants was similar to that in term infants. The vaccination program led to a division by a factor of 2.6 (95% confidence interval [CI], 1.3 to 5.2) in the number of hospitalizations for rotavirus diarrhea during the first two epidemic seasons following vaccine introduction and by a factor of 11 (95% CI, 3.5 to 34.8) during the third season. We observed significant effectiveness of the pentavalent rotavirus vaccine on the number of hospitalizations in a population of prematurely born infants younger than 3 years of age. A multicenter national study would provide better assessment of this impact. (This study [Impact of Systematic Infants Vaccination Against Rotavirus on Gastroenteritis Hospitalization: a Prospective Study in Brest District, France (IVANHOE)] has been registered at ClinicalTrials.gov under registration no. NCT00740935.)  相似文献   
4.
Fighter pilots are frequently exposed to high Gz acceleration which may induce in-flight loss of consciousness (G-LOC). One factor reducing tolerance to accelerations is a previous exposure to negative accelerations. This phenomenon, which happens during the first few seconds after the onset of the positive plateau, is called the push pull effect. Our goal was to validate a non human primate model in order to study push pull physiological mechanisms and possible changes in arterial pressure, which may occur after the first ten seconds of the positive acceleration plateau. Eight rhesus monkeys were centrifuged in profile runs, including positive Gz accelerations (+1.4, +2 and +3 Gz) with or without previous negative Gz acceleration (–2 and –3 Gz vs. +1.4 Gz). Heart rate, blood pressure and esophageal pressure were recorded during the entire centrifugation run. Results showed that the push pull effect was observed in the non human primate model. Moreover, the reduced tolerance to acceleration lingered longer than that during the first ten seconds after exposure to +Gz acceleration. It was found that, after the fourteenth second, mean blood arterial pressure stabilizes at a lower value, when the positive acceleration is preceded by a negative acceleration (15.8 kPa for –1 Gz and 15.5 for –2 Gz vs. 16.9 for 1.4 Gz). The chronology of the push pull effect seems to involve two periods. One has a short time span. The other one has a longer time span and could be induced by shift of pressure threshold, coming from exposure to previous negative acceleration.  相似文献   
5.
Molecular methods for the rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) are generally based on the detection of an S. aureus-specific gene target and the mecA gene. However, such methods cannot be applied for the direct detection of MRSA from nonsterile specimens such as nasal samples without the previous isolation, capture, or enrichment of MRSA because these samples often contain both coagulase-negative staphylococci (CoNS) and S. aureus, either of which can carry mecA. In this study, we describe a real-time multiplex PCR assay which allows the detection of MRSA directly from clinical specimens containing a mixture of staphylococci in <1 h. Five primers specific to the different staphylococcal cassette chromosome mec (SCCmec) right extremity sequences, including three new sequences, were used in combination with a primer and three molecular beacon probes specific to the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. Of the 1,657 MRSA isolates tested, 1,636 (98.7%) were detected with the PCR assay, whereas 26 of 569 (4.6%) methicillin-susceptible S. aureus (MSSA) strains were misidentified as MRSA. None of the 62 nonstaphylococcal bacterial species or the 212 methicillin-resistant or 74 methicillin-susceptible CoNS strains (MRCoNS and MSCoNS, respectively) were detected by the assay. The amplification of MRSA was not inhibited in the presence of high copy numbers of MSSA, MRCoNS, or MSCoNS. The analytical sensitivity of the PCR assay, as evaluated with MRSA-negative nasal specimens containing a mixture of MSSA, MRCoNS, and MSCoNS spiked with MRSA, was approximately 25 CFU per nasal sample. This real-time PCR assay represents a rapid and powerful method which can be used for the detection of MRSA directly from specimens containing a mixture of staphylococci.  相似文献   
6.
Objective To determine the incidence ofMalassezia furfur-related colonization and infection of central venous catheters.Design Prospective clinical study.Setting A paediatric intensive care unit at a University Hospital.Patients 66 newborns with central venous catheters for parenteral nutrition including lipid emulsions (Intralipid®).Methods When a central venous catheter was removed, it was rinsed with 1 ml of physiological saline, transported at ambient temperature to the clinical laboratory and cultured on Dixon's medium. The tip of the central venous catheter was used for a bacteriological study using Maki's technique. In case of suspected sepsis, blood cultures were obtained using an Isolator® tube.Results 74 central venous catheters were included: mean duration of use of a central venous catheters and infusions of lipid emulsion (Intralipid®) were 19.3±10 days and 8.6±8 days respectively. Only 2 central venous catheters (2.7%) were colonized byMalassezia furfur: (Mf) one in an asymptomatic newborn, and the other in an infected newborn with signs of sepsis, who most probably died at 4 months of age from refractory hypoxia due to pulmonary hypoplasia, but not from Mf sepsis.Conclusions The incidence ofMalassezia furfur-related colonization of central venous catheters appears to be low but not negligible, which warrants the use of specific culture techniques.This study was partially supported by a clinical research pilot study grant from INSERM France (91CN52)  相似文献   
7.
8.
Stimulant-use disorders have been associated with lower availability of dopamine type-2 receptors (D2R) and greater availability of type-3 receptors (D3R). Links between D2R levels, cognitive performance, and suppression of the default mode network (DMN) during executive functioning have been observed in healthy and addicted populations; however, there is limited evidence regarding a potential role of elevated D3R in influencing cognitive control processes in groups with and without addictions. Sixteen individuals with cocaine-use disorder (CUD) and 16 healthy comparison (HC) participants completed [11C]-(+)-PHNO PET imaging of D2R and D3R availability and fMRI during a Stroop task of cognitive control. Independent component analysis was performed on fMRI data to assess DMN suppression during Stroop performance. In HC individuals, lower D2R-related binding in the dorsal putamen was associated with improved task performance and greater DMN suppression. By comparison, in individuals with CUD, greater D3R-related binding in the substantia nigra was associated with improved performance and greater DMN suppression. Exploratory moderated-mediation analyses indicated that DMN suppression was associated with Stroop performance indirectly through D2R in HC and D3R in CUD participants, and these indirect effects were different between groups. To our knowledge, this is the first evidence of a dissociative and potentially beneficial role of elevated D3R availability in executive functioning in cocaine-use disorder.Subject terms: Addiction, Cognitive control  相似文献   
9.
Following gastrectomy for locally advanced adenocarcinomas, three patients developed microangiopathic hemolytic anemia and renal failure shortly after completing courses of adjuvant chemotherapy with mitomycin and 5-FU. These complications progressed despite cessation of chemotherapy, and all three patients died of noncardiogenic pulmonary edema precipitated in two cases by blood transfusions. At autopsy, two patients had no residual carcinoma and all had a diffuse microangiopathy involving mainly the kidneys and lungs. There was intimal hyperplasia of many arterioles sometimes associated with complete occlusion of the lumen, prominent nuclear atypia in many capillary cells, and numerous capillary fibrin thrombi. Direct immunofluorescence studies revealed extensive fibrinogen-fibrin deposits in the vascular lesions. Chemotherapy-induced microangiopathic hemolytic anemia and renal failure may predispose patients to fatal episodes of noncardiogenic pulmonary edema that can be triggered by blood transfusions.  相似文献   
10.
The clinical, electrophysiological and histopathological features in seven cases of cisplatinum peripheral neuropathy are reported and compared with the literature data. The neuropathy appears for an average intake of 500 mg/m2 of DDP. The symptoms are those of a symmetric, distal, predominantly sensitive neuropathy of an axonal type with major involvement of proprioception. Neurological improvement is poor after withdrawal of the drug. A post mortem study performed in one case showed a degeneration of the posterior column in the cord and residual nodules of Nageotte in a lumbar spinal ganglion. The systematic study of the tendon reflexes and distal pallesthesia in subjects treated with the drug, may reveal the neuropathy before the onset of the most disabling symptoms (paresthesia, ataxia, pain, Lhermitte's sign).  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