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   2990篇
  免费   196篇
  国内免费   23篇
耳鼻咽喉   44篇
儿科学   73篇
妇产科学   107篇
基础医学   474篇
口腔科学   135篇
临床医学   267篇
内科学   690篇
皮肤病学   18篇
神经病学   216篇
特种医学   66篇
外科学   487篇
综合类   48篇
预防医学   156篇
眼科学   29篇
药学   157篇
中国医学   10篇
肿瘤学   232篇
  2023年   25篇
  2022年   46篇
  2021年   86篇
  2020年   46篇
  2019年   82篇
  2018年   83篇
  2017年   56篇
  2016年   83篇
  2015年   71篇
  2014年   111篇
  2013年   147篇
  2012年   252篇
  2011年   249篇
  2010年   162篇
  2009年   136篇
  2008年   201篇
  2007年   193篇
  2006年   191篇
  2005年   185篇
  2004年   170篇
  2003年   127篇
  2002年   131篇
  2001年   22篇
  2000年   18篇
  1999年   28篇
  1998年   19篇
  1997年   26篇
  1996年   18篇
  1995年   17篇
  1994年   17篇
  1993年   13篇
  1992年   20篇
  1991年   14篇
  1990年   4篇
  1989年   4篇
  1988年   9篇
  1987年   11篇
  1986年   7篇
  1985年   12篇
  1984年   9篇
  1983年   5篇
  1982年   9篇
  1981年   4篇
  1980年   9篇
  1979年   7篇
  1978年   18篇
  1977年   5篇
  1971年   4篇
  1964年   3篇
  1894年   3篇
排序方式: 共有3209条查询结果,搜索用时 12 毫秒
21.
22.
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II.  相似文献   
23.
Weight regain following primary bariatric surgery occurs in a significant proportion of patients and is attributed to epidemiological, anatomical and metabolic factors. Surgical revision of these patients has significant risks and limited benefits. Endoscopic revisions that reduce gastric pouch size and diameter of the gastrojejunal anastomosis may offer an effective, safe, less invasive and even reproducible treatment. We herein discuss the indication, selection and feasibility of different endoscopic techniques that could be used in the management of weight regain following primary bariatric surgery. Future research could optimize a personalized approach not only in the endoscopic management but also in combination with other therapeutic modalities for weight regain after bariatric surgery.  相似文献   
24.
Summary In Switzerland, and in many other countries as well, the distribution of morbidity and perceived health in the general population and their determining factors have not been systematically studied so far. This article reports an exploratory study of prevalence of two complex health indicators, longstanding disease (Disease) and psychological well-being (Well-being) and of their environmental, person-specific and behavioural determinants. Data from a health survey conducted in five cantons and three language regions as part of the Swiss Intercantonal Health Indicators Project were used. Whereas distributions of prevalence of Disease according to gender, age, level of education and place of living confirm results of other studies, unexpected prevalence patterns were found for Well-being, especially with regard to gender differences. Multivariate analyses by general linear models (independent sub-samples of the study population were used to develop and validate models) showed different sets of environmental, person-specific and behavioural factors to explain inter-individual differences of Disease and Well-being, both in the total validation sample and in sub-samples of women and men. The results are discussed with regard to implications for socioepidemiological health research.
Zusammenfassung Wie in zahlreichen anderen Ländern so sind bisher in der Schweiz die Verteilung und die Determinanten von Morbidität und wahrgenommener Gesundheit in der Gesamtbevölkerung nicht systematisch untersucht worden. Die vorliegende Arbeit berichtet über eine explorative Studie über die Prävalenz zweier komplexer Gesundheitsindikatoren, länger andauernde Krankheit (Disease) und psychisches Wohlbefinden (Well-being), und über deren jeweilige umweltbedingte, personale und verhaltensbezogene Einflußfaktoren. Grundlage dafür waren Daten, die in einer Bevölkerungsbefragung in 5 Kantonen und 3 Sprachregionen im Rahmen des Interkantonalen Gesundheitsindikatorenprojekts (IGIPPROMES) erhoben wurden. Während die Verteilung der Prävalenz von Krankheit nach Geschlecht, Alter, Bildungsstatus und Wohnortgrösse den Ergebnissen anderer Studien entspricht, ergaben sich bei der Prävalenz von Wohlbefinden unerwartete Verteilungsmuster, insbesondere Unterschiede zwischen Frauen und Männern. Eine Analyse interindividueller Unterschiede von Krankheit und Wohlbefinden mit Hilfe eines allgemeinen linearen Modells (Modellentwicklung und Validierung an unabhängigen Teilstichproben) zeigte, dass diese durch jeweils spezifische Konstellationen von Umwelt-, Personen- und Verhaltensfaktoren erklärt werden können, sowohl in der gesamten Validierungsstichprobe als auch in den Teilstichproben für Frauen und Männer. Die Ergebnisse der Studie werden in Hinblick auf die Weiterentwicklung der sozialepidemiologischen Gesundheitsforschung diskutiert.

Résumé En Suisse, comme dans beaucoup d'autres pays, la morbidité et le bien-être psychologique de la population générale n'ont presque pas été étudiés jusqu'à présent. Dans ce rapport, les résultats d'une étude exploratoire sur deux indicateurs complexes de santé, maladie chronique (Disease) et bien-être psychologique (Well-being) et sur les facteurs de l'environnement, de la personnalité et du comportement qui influencent ces deux indicateurs sont présentés. Cette étude faisait part du projet intercantonal sur les indicateurs de santé (IGIP-PROMES) et se base sur les données tirées d'une enquête auprès des populations de cinq cantons et trois régions linguistique de la Suisse. Tandis que la prévalence de l'indicateur «maladie» par sexe, age, degré de formation et dimension du lieu de résidence était conforme aux résultats d'autres études, des distributions inattendues de la prévalence de «bien-être psychologique», notamment des différences entre hommes et femmes ont été trouvées. Une analyse des différences entre individue de «maladie» et «bien-être» au moyen d'un modèle linéaire généralisi — le développement et l'évaluation duquel ont été faits à l'aide de deux échantillons d'occasion indépendents — a montré que des constellations spécifiques constituées de facteurs de l'environnement, de la personnalité et du comportement, peuvent expliquer ces différences, soit dans l'échantillon d'évaluation totale, soit dans les échantillons partiels de femmes et d'hommes. Ces résultats sont discutés par rapport à l'évolution de la recherche socio-épidémiologique.


Paper presented at a symposium on The Public Health Perspective of Social and Preventive Medicine, in celebration of the 20th anniversary of the Department of Social and Preventive Medicine, University of Berne, 25 June 1992 in Berne.  相似文献   
25.
26.
Two outbreaks of typhoid fever caused by Salmonella typhi of the same phagotype (A, biotype II) and antibiotic susceptibility are reported. Both occurred during the war in Bosnia and Herzegovina. The first outbreak appeared among the refugees from the town of Jajce. The second outbreak appeared among the inhabitants in the village of Vidosi near Livno. This report describes main clinical, epidemioloigcal and laboratory findings for 22 patients treated in Split University Hospital, Croatia, in the period November 1992–January 1993. Possible epidemiological connections between those two outbreaks are discussed.  相似文献   
27.
28.
泽泻提取物不同组分对尿草酸钙结石形成的实验研究   总被引:6,自引:0,他引:6  
目的 :研究泽泻提取物不同组分对尿草酸钙结石形成的影响 ,并确定其抑制尿草酸钙结石形成的有效部位。方法 :通过喂服泽泻提取物不同组分对乙二醇和氯化铵诱导的大白鼠肾草酸钙结石模型进行实验研究。结果 :服用泽泻醋酸乙酯浸膏的醋酸乙酯洗脱液大鼠的血清尿素氮 (BUN) ,肌酐 (Cr) ,肾钙 (Ca2+ )含量 ,24h尿Ca2+ 分泌量 ,肾组织的草酸钙晶体沉积均明显低于成石组 (P<0.05)。结论 :泽泻醋酸乙酯浸膏的醋酸乙酯洗脱液能抑制实验性高草酸尿症大白鼠体内肾草酸钙晶体的形成 ,是泽泻抑制尿草酸钙结石形成的有效部位。  相似文献   
29.
PURPOSE: To discuss the absolute benefits from adjuvant systemic therapy knowledge of long-term outcomes and baseline risks of relapse and disease-specific survival are required. We assessed the 10-year outcomes in a population-based cohort of node-negative (N-) lymphovascular negative (LV-) early breast cancers diagnosed from 1989 to 1991 who did not receive adjuvant systemic therapy. METHODS: One thousand one hundred eighty-seven cases of pT(1-2)N(0) LV- breast cancers with a median follow-up of 10.4 years were reviewed. Kaplan-Meier survival curves for relapse free survival (RFS), breast cancer-specific survival (BCSS) and overall survival (OS) were compared with log-rank tests with cohorts stratified for tumor size and grade. RESULTS: The median age of this series was 62 years. Four hundred thirty tumors were < or = 1 cm in diameter (cohort 1), 507 were 1.1-2 cm (cohort 2), and 250 were 2.1 to 5 cm in diameter (cohort 3). The 10-year outcomes for cohorts 1, 2, and 3, respectively, were significantly different: RFS, 82%, 75%, and 66%; BCSS, 92%, 90%, and 77%; and OS, 79%, 78%, and 66%. Tumor grade significantly altered outcome within size cohorts, particularly in pT(1)N(0) breast cancers. CONCLUSION: This study provides detailed information on the continued relapse and breast cancer death rate to 10 years of follow-up. Specifically, without adjuvant systemic therapy, patients with LV-, N - breast cancer had a > or = 25% 10-year risk of relapse and a corresponding 10-year breast cancer death rate of > or = 10% if they had either a grade 3 tumor < or = 1 cm, a grade 2 to 3 tumor from 1.1 to 2 cm, or any grade tumor greater than 2 cm.  相似文献   
30.
PURPOSE: BRCA1-related breast cancers are more frequently estrogen receptor (ER) negative than are either BRCA2-related or nonhereditary breast cancers. The relationship between ER status and other clinical features of hereditary breast cancers has not been well studied. EXPERIMENTAL DESIGN: ER status, grade, and histological tumor type were evaluated in 1131 women with invasive breast cancer, ascertained at 10 centers in North America. There were 208 BRCA1 mutation carriers, 88 BRCA2 carriers, and 804 women without a known mutation. We stratified the patients by mutation status, grade, age, and histological type and calculated the percentage of ER-positive tumors within each stratum. RESULTS: BRCA1 mutation carriers were more likely to have ER-negative breast cancers than were women in other groups, after adjustment for age, grade, and histological subtype (P < 0.001). Only 3.9% of BRCA1-related breast cancers were ER-positive cancers occurring in women in their postmenopausal years. The direction and magnitude of the change in ER status with increasing age at diagnosis in BRCA1 carriers was significantly different from in BRCA2 carriers (P(intercept) = 0.0002, P(slope) = 0.04). Notably, changes in ER status with age at diagnosis for BRCA1 carriers and noncarriers were almost identical (P(slope) = 0.98). CONCLUSIONS: The strong relationship between the presence of a BRCA1 mutation and the ER-negative status of the breast cancers is neither a consequence of the young age at onset nor the high grade but is an intrinsic property of BRCA1-related cancers. The ER-negative status of these cancers may reflect the cell of origin of BRCA1-related cancers.  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