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991.
Zusammenfassung Fragestellung: Die arterielle Switch-Operation ist Methode der Wahl zur operativen Korrektur einer einfachen Transposition der gro?en Arterien im Neugeborenenalter. Bei erfreulichen kurzzeitigen Ergebnissen ist die Langzeitprognose der betroffenen Kinder unklar. Methode: Wir analysierten retrospektiv den Verlauf von 165 konsekutiven Patienten mit Transposition der gro?en Arterien nach arterieller Switch-Operation zwischen 1986 und 1993 (Operationsalter 9±7 Lebenstage; 15 Patienten mit gleichzeitigem Verschlu? eines Ventrikelseptumdefekts; Nachbeobachtungsdauer 43±24 Monate). Ergebnisse: Neun Patienten (5,5%) verstarben früh, 3 Patienten sp?t nach der arteriellen Switch-Operation. Bei 4 Patienten bestehen Zeichen eines alten Myokardinfarkts im EKG. 18 Patienten weisen eine deutliche Stenosierung der peripheren Pulmonalarterien auf (Dopplergradient 30–50 mmHg, n=14; >50 mmHg, n=4). Aufgrund einer Aortenisthmusstenose (9 Patienten), peripheren Pulmonalstenose (1 Patient), subvalvul?ren Pulmonalstenose (1 Patient) und eines Verschlusses der linken Koronararterie (1 Patient) wurden bei 12 Patienten Zweitoperationen durchgeführt. Bei 22 Patienten besteht der Verdacht auf eine psychomotorische Retardierung, 2 Kinder entwickelten einen ventilpflichtigen Hydrozephalus. Nach dem 2. Lebensjahr erhielt nur 1 Kind (mit ventrikul?rer Arrhythmie) eine medikament?se Therapie. 131 Kinder entwickeln sich normal. Schlu?folgerung: Die arterielle Switch-Operation führt in der Regel zu sehr guten mittelfristigen Ergebnissen. Langfristige Nachbeobachtungen sind jedoch erforderlich, um definitive Aussagen über die Dauerhaftigkeit der guten Ergebnisse machen zu k?nnen.   相似文献   
992.
Occupational exposures such as crystalline silica, diesel engine exhaust, polycyclic aromatic hydrocarbons, and man-made mineral fibers are strongly suspected to increase lung cancer risk. Two case-control studies in Germany conducted between 1988 and 1996 were pooled for a joint analysis. A total of 3,498 male cases and 3,541 male population controls, frequency matched for age and region, were included in the study. The lifelong history of all jobs and industries was coded and occupational exposures were evaluated by expert rating. Odds ratios, crude and adjusted for smoking and asbestos exposure, were calculated by conditional logistic regression. Job-related evaluation showed a statistically significant increased odds ratio adjusted for smoking among farmers; forestry workers, fishermen, and livestock workers; miners and quarrymen; chemical processors; cabinet makers and related wood workers; metal producers and processors; bricklayers and carpenters; road construction workers, pipelayers and well diggers; plasterers, insulators, and upholsterers; painters and lacquerers; stationary engine and heavy equipment operators; transport workers and freight handlers; and service workers. With regard to specific occupational exposures, elevated odds ratios (OR) (95% confidence intervals (CI)) for lung cancer risk adjusted for smoking and asbestos exposure were observed for man-made mineral fibers (OR = 1.48, 95% CI 1.17, 1.88); crystalline silica (OR = 1.41, 95% CI 1.22, 1.62); diesel engine exhaust (OR = 1.43, 95% CI 1.23, 1.67); and polycyclic aromatic hydrocarbons (OR = 1.53, 95% CI 1.14, 2.04). The risk of asbestos exposure, adjusted for smoking was also increased (OR = 1.41, 95% CI 1.24, 1.60).  相似文献   
993.
994.
995.
A personal diary may be more appropriate than a questionnaire for assessing self-reported current use of hormone therapy (estrogens, progestagens, or their combination); however, use of a questionnaire is more feasible and less expensive. The authors compared both methods for 16,060 Swedish women aged 45-73 years from the Malmo Diet and Cancer Study (baseline, 1991-1996). In a reliability analysis, the authors investigated the agreement (kappa value) between the questionnaire and the diary regarding current hormone therapy use (yes vs. no), studying the ability to replicate results whether or not they were correct. They also explored associations between discrepancy and individual characteristics. A validity analysis was conducted to determine whether use of the questionnaire achieved an outcome without systematic error (i.e., high specificity and sensitivity); the personal diary was considered the "gold standard." Agreement between both methods was high: 95.5% (kappa = 0.840). The sensitivity was 84.9% and the specificity 97.7%. Higher body mass index and being a widow were associated with agreement, whereas age (50-59 years), use of anxiolytics/hypnotics or opiates, high alcohol consumption, past smoking, and higher educational level were associated with discrepancy. Compared with a personal diary, a simple self-administered questionnaire is a valid method for assessing current use of hormone therapy.  相似文献   
996.
The transportation of gaseous contaminant from a low and moderate low impulse (momentum<1 m s(-1)) source to the breathing zone was studied in a uniform air stream flow. Results of the effects of the direction and the velocity of principal air flow, convection due to a human body, arm movement of a human being and the type of source on the concentration profiles are presented. Three important results were obtained. Firstly, for a given low and moderate impulse low impulse contaminant source in the near field of a worker, his/her orientation relative to the principal air flow direction is the most important factor in reducing occupational exposure, with an air velocity of about 0.3 m s(-1). Secondly, the effect of convection resulting from body heat on air flow was lower than expected. Thirdly, arm movements influence contaminant dispersion, and should be included when models assessing exposure are developed. The present data can also be used to validate existing computational fluid dynamic (CFD) models.  相似文献   
997.
We examined the effects of dietary fat type (10% of either soybean oil, S, or beef tallow, T)(3) and xylanase supplementation (-, without; +, with 1 g of Avizyme 1300 per kg diet) in rye- based diets (56%) on tissue protein synthesis in male broilers. Birds were injected with a large flooding dose of a phenylalanine solution (150 mmol/L, 38 atom percentage excess [(15) N] phenylalanine) and tissues were obtained after a 10-min incorporation period. [(15) N]-enrichment in tissue free phenylalanine and tissue protein bound phenylalanine were measured by gas-chromatography mass-spectrometry and by gas-chromatography combustion isotope ratio mass-spectrometry, respectively in order to calculate tissue specific fractional rates of protein synthesis (k(s)). The k(s) (%/d) in (S-), (S+), (T-) and (T+)-fed birds were 56, 64, 84 and 61 (SEM = 3.7) in duodenum, 51, 52, 75 and 58 in jejunum (SEM = 3.1), 66, 67, 105 and 68 (SEM =7.0) in jejunal mucosa cells, 53, 56, 68 and 50 (SEM = 3.7) in ileum and 52, 45, 118 and 39 (SEM = 20.2) in pancreas, respectively. Significant fat, enzyme or interaction effects in these tissues were mainly caused by the elevated k(s) in (T-)-fed birds which was closely associated with intestinal viscosity. We conclude that the effect of soluble nonstarch polysaccharides (NSP) and of NSP-hydrolyzing enzymes may be explained partially by modification in tissue protein synthesis of the intestinal tract.  相似文献   
998.
999.
The air-exchange rate is often low in schools. The authors studied the possible impact of improving school ventilation on health and exposure of pupils. Questionnaire data on allergies, asthma, and asthmatic symptoms were obtained in 1993 and 1995 for 1,476 primary- and secondary-school pupils in 39 randomly selected schools. Various exposure factors were measured in 1993 and 1995 in approximately 100 classrooms. In 12% of the classrooms, new ventilation systems were installed between 1993 and 1995; the subsequent air-exchange rate increased and the relative humidity and concentration of several airborne pollutants were reduced compared with classrooms in nonimproved buildings. The reporting of at least one asthmatic symptom and the reporting of more asthmatic symptoms in 1995 than in 1993 were less common among the 143 pupils who attended schools with new ventilation systems.  相似文献   
1000.
To study the intestinal metabolism of lignans, the concentrations of plant and mammalian lignans in intestinal digesta sampled along the intestinal tract of pigs were determined by isotope dilution GC-MS. The pigs were fed rye-bread diets made from either whole rye-grains or rye-grain milling fractions enriched in pericarp-testa, aleurone or endosperm cells. The content and characteristics of dietary fibre varied between diets and had been shown to induce different colon fermentation patterns. As the metabolism of lignans depends on the action of the intestinal flora, we tested whether the rye-bread diets influence the metabolism of lignans. In the ileum, the lignans were mainly present as conjugated plant lignans, which were determined only when the analytical procedure included a hydrolysis step. High recovery of dietary lignans in the ileum may indicate that the lignans enter the enterohepatic circulation. In addition, two to three times the intake of lignans were recovered in the faeces when the diets had a high content of dietary fibre suggesting underestimation of plant lignans in the diet. Most of the plant lignans disappeared from the intestinal tract between the terminal ileum and the caecum. The intestinal concentrations and the disappearance of lignans correlated with the content of lignans in the diet, being highest on the pericarp-testa diet and lowest on the endosperm diet. No effect of fermentation pattern on the intestinal metabolism of lignans was observed. The lignans were liberated from the pericarp-testa diet although the plant cell walls remained largely undegraded.  相似文献   
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