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E M Zinberg  D I Choo  L A Zotter 《Microsurgery》1989,10(2):103-7; discussion 108-9
The effect of five different irrigating solutions on patency of four different types of microvascular anastomoses was studied. The solutions used were lactated Ringer's without heparin and four lactated Ringer's solutions with varying concentrations of heparin ranging from 10,000 units/liter to 100,000 units/liter. These were tested on four different anastomotic models in the rat: 1) end-to-end femoral arterial anastomosis; 2) end-to-side arterial bypass graft; 3) end-to-end venous anastomosis; and 4) end-to-side venous bypass graft. There were statistically significant differences in patency rates among the solutions only in the end-to-end venous anastomosis group. In these, significantly higher patency was achieved with heparinized lactated Ringer's solution at 20,000 units/liter. The use of higher concentrations of heparin in these solutions resulted in decreasing patency rates and appears to be contraindicated.  相似文献   
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The combination of small-animal PET and MRI data provides quantitative in vivo insights into cardiac pathophysiology, integrating information on biology and morphology. We sought to determine the feasibility of PET and MRI for the quantification of ischemic injury in the rat model. METHODS: Fourteen healthy male Wistar rats were studied with 18F-FDG PET and cine MRI. Myocardial viability was determined in a transmural myocardial infarction model in 12 additional rats, using 18F-FDG PET and delayed-enhancement MRI with gadolinium-diethylenetriaminepentaacetic acid. All PET was acquired with a dedicated small-animal PET system. MRI was performed on a 1.5-T clinical tomograph with a dedicated small-animal electrocardiographic triggering device and a small surface coil. RESULTS: In normal rats, 18F-FDG uptake was homogeneous throughout the left ventricle. The lowest mean uptake of the 18F-FDG was found in the apical regions (79% +/- 6.0% of maximum) and the highest uptake was in the anterior wall (93% +/- 4.3 % of maximum). Myocardial infarct size as determined by histology correlated well with defects of glucose metabolism obtained with 18F-FDG PET (r = 0.89) and also with delayed-enhancement MRI (r = 0.91). Left ventricular ejection fraction in normal rats measured by cine MRI was 57% +/- 5.4% and decreased to 38% +/- 12.9% (P < 0.001) in the myocardial infarction model. CONCLUSION: Integrating information from small-animal PET and clinical MRI instrumentation allows for the quantitative assessment of cardiac function and infarct size in the rat model. The MRI measurements of scar can be complemented by metabolic imaging, addressing the extent and severity of ischemic injury and providing endpoints for therapeutic interventions.  相似文献   
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Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea.  相似文献   
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For all persons who died in the city of Dresden and 7 surrounding counties from 1967 to 1978, documents relating to the clinical and pathologic diagnosis were examined and findings compared. The study covered nearly two thirds of all deaths which occurred in the district of Dresden during this time period. The autopsy rate overall was found to be 22.8%. In 57.3% the clinical diagnoses were found to have been correct, in 19.7% they corresponded in part, but in 23% there was no concordance whatsoever between the clinical and autopsy diagnoses. The influence of age, place of death and disease group on the agreement between clinical and underlying pathoanatomic diagnosis was also examined. The analysis highlighted the degree to which death statistics based on the death certificate are misleading. In up to 28.8% of cases there were formal errors in the underlying disease diagnosis listed by the certifying physician on the death certificate. The value of regular comparison between the diagnoses, and its usefulness for training and continuing medical education are emphasized. The results of the study underline the importance of making available more prospectors in the district of Dresden to meet the expanding tasks of the clinically active pathologist in autopsy and biopsy diagnostic efforts.  相似文献   
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Facially amphiphilic polymers carrying cationic and hydrophobic groups on the same repeat unit have shown promising antimicrobial activity and biocompatibility, yet they are prone to suffer from protein adhesion which may induce biofilm formation. To overcome this problem, poly(diitaconate)-based copolymers with cationic/hydrophobic and protein-repellent/charge-neutral repeat units are synthesized. The bioactivity profile of surface-attached polymer networks made from these copolymers depends on the ratio of the cationic and charge-neutral repeat units. In all cases, the protein adhesion is substantially reduced compared to purely cationic polymers. At a 50:50 ratio, the polymer coatings are partially protein-repellent and antimicrobial, yet slightly cell toxic. At an intermediate composition of 30:70, they are still antimicrobial and the cell compatibility is substantially improved. The long-term stability of these materials still has to be determined to judge their suitability for medical applications.  相似文献   
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Introduction Women with a pathogenic BRCA1/2 mutation have a markedly increased lifetime risk of developing breast and/or ovarian cancer. The current preventive treatment alternatives that are offered are an intensified breast cancer screening programme and risk-reducing operations. Before deciding on one option, medical and personal factors such as life situation and individual preferences must be weighed carefully. Decision aids are used internationally to support BRCA1/2 mutation carriers during their decision-making process. In this study these are analysed structurally for the first time and their applicability to the German context is examined. Material and Methods A systematic literature search in five electronic databases and a manual search were performed. The identified decision aids were evaluated with regard to formal criteria, medical content and quality. The qualitative assessment used the criteria of the International Patient Decision Aid Standards Collaboration (IPDASi v4.0), which examined various dimensions (e.g., information, probabilities, values). Results Twenty decision aids, which were published between 2003 and 2019 in Australia (n = 4), the United Kingdom (n = 3), Canada (n = 2), the Netherlands (n = 2) and the USA (n = 9), were included. Nine focus on BRCA1/2 mutation carriers and eleven include other risk groups. Eighteen include risk-reducing operations as decision options, 14 list screening methods for breast and/or ovarian cancer, and 13 describe the possibility of pharmacological prevention by means of selective oestrogen receptor modulators or aromatase inhibitors. Nine of the 20 decision aids meet fundamental quality criteria (IPDASi v4.0 qualification criteria). Conclusion International decision aids can serve formally as a basis for a German decision aid for BRCA1/2 mutation carriers. Some of them differ markedly in content from the recommendations of German guidelines. Only a few achieve a high quality. Key words: BRCA1, BRCA2, decision aid, familial breast cancer, familial ovarian cancer  相似文献   
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AIM: We examined the impact of advanced maternal age (>40 years old) on the survival of twin small-for-gestational-age (SGA) infants, that is, infants who were smaller in size than was expected for the baby's sex, genetic heritage, and gestational age. METHODS: The present study was a retrospective cohort study on twin live births in the USA from 1995 to 1998 inclusive. Two categories of SGA babies were defined: discordant (when only one of a twin pair was SGA) and concordant (when both were SGA). Otherwise, the twin pair was appropriate-for-gestational-age (AGA) concordant. RESULTS: 192,195 twin pairs were analyzed. The incidence of SGA discordance and concordance was 11.8% and 3.9%, respectively. The occurrence of both SGA subtypes tended to decrease with increasing maternal age. The unadjusted risk for neonatal mortality increased when both twins were affected (15.8: 22.8 and 56.6 per 1000 among AGA concordant, SGA discordant and SGA concordant twins; P-value for trend < 0.0001). Using maternal-age-specific AGA babies as reference, the adjusted risk for neonatal mortality climbed progressively with advancing maternal age in a dose-dependent pattern, being lowest among teenagers and highest in mothers aged > or =40 years. CONCLUSIONS: SGA discordance and concordance declined with advancing maternal age. In contrast, neonatal mortality of both SGA subtypes worsened with the increase in maternal age compared with that of the age-specific AGA infants. These findings are potentially useful to care providers in counseling older women, a group that is progressively increasing in size and is most susceptible to twining.  相似文献   
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