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21.
Health care delivery in Mexico is divided in three groups: a social sector that covers approximately 53% of the population and is financed by the labor force, the state and the employer; a public, or open, sector that covers 33% of the population and is financed by federal and state funds; and a private sector that covers about 5% of the population and has two categories, the not-for-profit hospitals and the profit-oriented institutions. Most medical practitioners can work in any of the three groups or in several. Nine percent of Mexico's population, because of extreme ignorance, poverty, or isolation, have no or limited access to medical care. Mexico has 58 medical schools, which graduate about 7800 new physicians annually, awarding them the title Medico cirujano (Physician Surgeon). There are more than 160,000 physicians in Mexico, 20,000 of whom are unemployed. Each year, approximately 12,000 physicians compete for the 4306 places in the official residency training programs for all specialties. Of those taking the examination, 2000 try to get one of the 625 slots available for training in general surgery. Most of the surgical training programs in Mexico have a 3-year duration. The Mexican Academy of Surgery, the Mexican Society of General Surgery, and the Mexican Board of Surgery, as well as private individuals and organizations, are working to improve the quality of medical education and trying to establish a 5-year training program in surgery. The rapid movement toward modernization that is sweeping the country must include the improvement of surgical education as well.
Resumen La atención de la salud en México está dividida en tres grupos: el Sector Social que cubre approximadamente el 53% de la población y que está financiado por la fuerza laboral, el Estado y el empleador; un Sector Público o Abierto que cubre el 33% de la población y que es financiado con fondos federales y estatales; y un Sector Privado que cubre el 5% de la población y que posee dos categorías: la de los hospitales sin ánimo de lucro y la de las instituciones con ánimo de lucro. La mayoría de los médicos pueden trabajar en cualquiera de los 3 grupos, o en combinación. El 9% de la población mexicana, por extrema ignorancia, pobreza y aislamiento no posee acceso alguno, o sólo lo tiene mínimo, a la atención médica.México posee 58 facultades de medicina, las cuales gradúan alrededor de 7.800 nuevos médicos anualmente, a quienes se les expide el título de médico cirujano.Hay más de 160.000 médicos en México, 20.000 de los cuales se encuentran desempleados. Cada año aproximadamente 12.000 médicos compiten por las 4.306 plazas en los programas oficiales de adiestramiento en las diferentes especialidades. De aquellos que presentan examen, 2.000 tratan de obtener uno de los 625 lugares disponibles para adiestramiento en círugía general.La mayoría de los programas de adiestramiento quirúrgico en la nación son de tres años de duración. La Academia Mexicana de Cirugía, la Asociación Mexicana de Cirugía General y el Consejo Mexicano de Cirugía, así como individuos y organizaciones privadas, trabajan en pro del mejoramiento de la calidad de la educación médica y tratan de establecer un programa de adiestramiento en cirugía de cinco años de duración. Los rápidos cambios de modernización que ocurren en el país deben incluir también el mejoramiento de la educación quirúrgica.

Résumé L'administration des soins au Mexique est repartie entre trois secteurs: 1) Le secteur social qui couvre environ 53% de la population et qui est financé par la caisse des ouvriers, celle de l'état et celle du patronat; 2) un secteur public ou ouvert, qui couvre environ 33% de la population et qui est financé par des fonds fédéraux et gouvernementaux et enfin 3) un secteur privé, qui ne couvre que 5% environ de la population et qui comprend deux catégories, les hôpitaux à but non-lucratif et les institutions à but lucratif. La plupart des médecins peuvent exercer dans un ou plusieurs de ces trois groupes. Neuf pourcent de la population, en raison d'une extrême pauvreté, de son ignorance ou de son éloignement, a peu ou pas d'accés à des soins structurés.Il y a 58 écoles de Médecine au Mexique, produisant environ 7800 nouveaux médecins par an. Ils reçoivent le titre de Medico Cirujano littéralement, Médecin chirurgical. Il existe plus de 160000 médecins au Mexique, dont 20000 sont sans travail. Chaque année, environ 12000 médecins sont en compétition pour obtenir un des 4306 postes officiels de résidents, toutes spialités confondues. Parmi ceux qui se présentent, 2000 sont candidats pour un poste en chirurgie. La plupart des programmes d'enseignement durent trois ans. L'Académie de Chirurgie Mexicaine, La Société Mexicaine de chirurgie Générale et le comité d'accréditation chirurgicale, tout en accord avec les institutions privées et leur dirigeants oeuvrent pour un programme de cinq ans. La vague de progrès, ressentie dans tous les domaines, qui traverse actuellement le pays doit aussi intéresser l'amélioration de l'enseignement en chirurgie.
  相似文献   
22.
Seventy-eight patients with cirrhosis were prospectively followed for up to 20 months, on the average. At entry into the study, galactose elimination capacity, aminopyrine breath test, and ICG clearance were measured. At the end of the study, 27 patients had died. Univariate analysis using the Kaplan-Meier method showed that both quantitative liver function tests (galactose elimination capacity:P<0.025; aminopyrine breath test:P<0.001; ICG clearance:P<0.005) and common clinical and biochemical data (encephalopathy:P<0.001; ascites:P<0.001; serum bilirubin:P<0.005; serum albumin:P<0.001; prothrombin index:P<0.05) were significant predictors of survival. To investigate whether quantitative liver function tests could contribute to a better definition of the prognosis, once Pugh score had already been taken into account, a multiple regression analysis according to the Cox model was performed. Pugh score and galactose elimination capacity resulted in the only independent prognostic covariates. From them a prognostic index was calculated, and the model was validated in an additional sample of 70 patients investigated according to the same protocol. The contribution GEC gave to the assessment of overall prognosis over that obtained using the Pugh score was slight, as estimated by the statistical parameters of the Cox's model, but was significant as assessed by a ROC curve analysis (P=0.05). These data show that all quantitative liver function tests were predictors of survival in cirrhosis, and that the galactose elimination capacity added some new prognostic information to those already available using the Child-Turcotte-Pugh classification.This study was supported in part by a grant from the Italian Ministry of Education (National Project Liver Cirrhosis). Part of this study was presented at the 22nd Meeting of the European Society for Clinical Investigation, Graz, Austria, April 20–23, 1988.  相似文献   
23.
BACKGROUND: We conducted a phase I/II study of weekly irinotecan [30 min intravenous (i.v.) infusion] combined with 5-fluorouracil (5-FU 3 g/m(2) weekly 48 h i.v. infusion, TTD regimen) as first-line chemotherapy for patients with advanced colorectal cancer (CRC). PATIENTS AND METHODS: The maximum tolerated dose (MTD) and the dose-limiting toxicity (DLT) in the treatment of gastrointestinal solid tumors (in phase I), and the antitumor activity and toxicity of the recommended phase I dose (in phase II) were determined. RESULTS: Diarrhea was the DLT, and irinotecan 80 mg/m(2) plus 5-FU 3 g/m(2) was the recommended phase I dose. In phase II, the confirmed response rate was 44% [95% confidence interval (CI) 29% to 59%] and the median overall survival was 23.8 months. However, grade 3/4 diarrhea affected 59% of patients and led to withdrawal of three patients. A second cohort of patients studied using the same schedule but with a reduced 5-FU starting dose of 2.25 g/m(2) showed improved tolerance (the incidence of grade 4 diarrhea decreased from 28% to 11% and overall grade 3/4 diarrhea to 56%, with no patient withdrawals) but the confirmed response rate was 28% (95% CI 14% to 45%) and median overall survival was 17.2 months. CONCLUSIONS: We found weekly irinotecan 80 mg/m(2) plus TTD regimen (5-FU 2.25 g/m(2) given as 48-h i.v. infusion) to be a feasible and active combined chemotherapy for the first-line treatment of advanced colorectal cancer.  相似文献   
24.
Purpose: The objective of this multicenter study was to compare the efficacy and toxicity profiles of a combination of 5-fluorouracil (5-FU) given by bolus injection together with intravenous leucovorin (LV) versus high-dose 5-FU in continuous infusion (CI) in the treatment of advanced colorectal cancer.Patients and methods: A total of 306 patients were randomized to receive either 5-FU 425 mg/m2 given by bolus injection on days 1–5 plus intravenous (i.v.) LV 20 mg/m2 every four to five weeks or 5-FU 3.5 g/m2/week in a 48-hour CI. Therapy was continued until disease progression. Second-line chemotherapy was allowed in both arms.Results: The response rates in 306 patients with measurable lesions were 19.2% (modulated arm) and 30.3% (CI arm, P < 0.05). The median progression-free survival times were 23.5 weeks (modulated arm) and 25 weeks (CI arm, P = NS). Median survival times were 42.5 weeks (modulated arm) and 48 weeks (CI arm, P = NS). There were no significant differences in grade 3–4 toxicity profiles but if we consider all grades we observed more mucositis in the modulated arm and more hand-foot syndrome in the CI arm.Conclusions: In terms of response rate, the continuous infusion regimen was more effective than the modulated regimen. There was no significant difference in survival and time to progression, and none in grade 3–4 toxicity.  相似文献   
25.
PURPOSE: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients. PATIENTS AND METHODS: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion. RESULTS: By intent-to-treat analysis, in 85 assessable patients, the objective response rate was 35% (95% CI, 25% to 46%), and stable disease was 33% (95% CI, 23% to 44%). Median time to progression was 8.0 months (95% CI, 6.0 to 10.0 months), and median overall survival time was 15.3 months (95% CI, 13.8 to 16.9 months). Toxicity was moderate. Grade 3 and 4 neutropenia, diarrhea, and asthenia were observed in 21%, 17%, and 13% of patients, respectively. Only one case of neutropenic fever occurred. There were two toxic deaths, one was a result of grade 4 diarrhea and acute kidney failure, and the other was a result of massive intestinal hemorrhage in the first cycle. The study of prognostic factors did not reveal any predictive factor of response. Response to treatment and baseline lactate dehydrogenase were the main factors conditioning progression-free and overall survival. CONCLUSION: Twice a month continuous-infusion CPT-11 combined with FU is a valid therapeutic alternative for elderly patients in good general condition.  相似文献   
26.
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28.
BACKGROUND/AIMS: To determine the levels of cyclosporin A (CsA) in tears and the anterior segment of the eye following long-term oral intake for autoimmune diseases. METHODS: Subjects taking oral CsA to treat relapsing autoimmune ocular inflammation were included in this study. All of the patients had been quiescent for at least 6 months. In patients scheduled for cataract extraction (group A), the CsA levels in the blood, aqueous humour and anterior capsule of the lens were determined. In subjects not requiring surgical intervention (group B), CsA was measured in tears and blood. The samples were analysed using turbulent flow chromatography coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: There were 19 subjects in group A and 43 subjects in group B. CsA was detectable in all of the tear samples with a mean value of 22.4 +/- 20.2 ng/ml and there was a significant positive correlation between the CsA levels in tears and blood (P = 0.012). CsA was not detected in any of the surgical samples. CONCLUSION: LC-MS/MS proved very sensitive for detecting CsA in low-volume biological samples. CsA was present in human tears in proportion to the blood level after an average of 12 hours from the last oral intake.  相似文献   
29.

Introduction

A prospective phase II study was conducted to assess the clinical activity and tolerability of oxaliplatin, capecitabine, and radiotherapy (RT) for neoadjuvant therapy of stages II?CIII rectal cancer.

Materials and methods

Patients with histologically confirmed stages II?CIII (T3?CT4 and/or N+) resectable rectal adenocarcinoma were eligible. Capecitabine was administered at 825?mg/m2 twice daily for 5?days/week and oxaliplatin at 50?mg/m2 on day 1 weekly for 5?weeks starting the first day of RT (before RT). RT consisted of a total dose of 45?Gy delivered in 25 fractions of 1.8?Gy, 5?days per week, for 5?weeks.

Results

A total of 46 patients were included (35 male, 10 female, median age 62?years). TNM Stage was T3 in 43 patients and T4 in 2. Twenty-eight patients had suspected nodal involvement. The intended chemoradiation treatment was completed in 94?% patients. Grade 3/4 toxicity included lymphocytopenia (6 patients), diarrhea (4 patients), emesis (2 patients), asthenia (3 patients), anorexia (1 patient), and hepatic toxicity (1 patient). Grade 1 neurotoxicity occurred in 18 patients, Grade 2 neurotoxicity in 3, and Grade 1 palmoplantar erythrodysesthesia in 2. Forty-two patients underwent surgery (complete resection 95?%, sphincter-saving operation 55?%). The overall pathologic response rate was 83?%, with a pathologic complete response (pCR) rate of 11.9?% (95?% CI 4.0?C25.6).

Conclusions

The pCR rate observed with oxaliplatin plus capecitabine and RT did not reach the pre-specified criteria of efficacy in this trial, which is in line with recent results of randomized phase III trials.  相似文献   
30.
Proton magnetic resonance spectroscopy (MRS) is a noninvasive method to assess concentrations of different metabolites in tissues, including the brain. We evaluated a fetus with growth restriction using Doppler ultrasound and proton MRS. Doppler assessment revealed absent end diastolic flow in the umbilical artery. Diastolic flow was increased in the middle cerebral artery. Proton MRS of the fetal brain showed lactate and a low N-acetylaspartate/choline index, metabolic markers of starvation/hypoxia. Proton MRS gave us in vivo metabolic information of the brain of a fetus under starvation/hypoxic conditions. It is potentially a new tool for fetal surveillance. To our knowledge, this is the first report of cerebral lactate detection using proton MRS in a growth-restricted human fetus with no associated malformations in the English literature. Further experimental and clinical longitudinal investigations are needed to evaluate its efficacy in the clinical setting.  相似文献   
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