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991.

Objective

To determine the prevalence, risk factors, and rate of vertical transmission of HBV and/or HCV infection among pregnant women in Upper Egypt, and assess the preventive efficacy of administering hepatitis B immunoglobulin and vaccine to newborns on their carrier status at 8 months.

Methods

Five hundred pregnant women were screened for HCV and HBV serum markers by enzyme-linked immunoassay. Those testing positive had their status confirmed by polymerase chain reaction and their levels of liver enzymes and interferon gamma were evaluated. The newborns of HBV-positive women received hepatitis B immunoglobulin and vaccine and were followed up to assess the rates of vertical transmission and carrier status among the newborns.

Results

Of the 500 pregnant women, 6.4% were HCV positive, 4.0% were HBV positive, and 1.0% were both. The vertical transmission rate was 3.1% for HCV, 30.0% for HBV, and 20.0% for a combined infection. The carrier rate of the infants at the end of their eighth month was 10.8% for those with HCV and 8% for those with HBV.

Conclusion

Infection with HBV and/or HCV is highly prevalent among pregnant women in Upper Egypt. The rate of vertical transmission was also high. Administering hepatitis B vaccine and immunoglobulin resulted in a 92% reduction in carrier status among newborns.  相似文献   
992.

Purpose  

To report three cases of migrated levonorgestrel intrauterine device (LNG-IUS) into the pelvic/abdominal cavity removed laparoscopically with the aid of preoperative computed tomography (CT) scan imaging.  相似文献   
993.
994.
PURPOSE: Noninvasive functional imaging, monitoring, and quantification of analytes transport in epithelial ocular tissues are extremely important for therapy and diagnostics of many eye diseases. In this study the authors investigated the capability of optical coherence tomography (OCT) for noninvasive monitoring and quantification of diffusion of different analytes in sclera and cornea of rabbit eyes. METHODS: A portable time-domain OCT system with wavelength of 1310 +/- 15 nm, output power of 3.5 mW, and resolution of 25 mum was used in this study. Diffusion of different analytes was monitored and quantified in rabbit cornea and sclera of whole eyeballs. Diffusion of water, metronidazole (0.5%), dexamethasone (0.2%), ciprofloxacin (0.3%), mannitol (20%), and glucose solution (20%) were examined, and their permeability coefficients were calculated by using OCT signal slope and depth-resolved amplitude methods. RESULTS: Permeability coefficients were calculated as a function of time and tissue depth. For instance, mannitol was found to have a permeability coefficient of (8.99 +/- 1.43) x 10(-6) cm/s in cornea and (6.18 +/- 1.08) x 10(-6) cm/s in sclera. The permeability coefficient of drugs with small concentrations (where water was the major solvent) was found to be in the range of that of water in the same tissue type, whereas permeability coefficients of higher concentrated solutions varied significantly. CONCLUSIONS: Results suggest that the OCT technique might be a powerful tool for noninvasive diffusion studies of different analytes in ocular tissues. However, additional methods of OCT signal acquisition and processing are required to study the diffusion of agents of small concentrations.  相似文献   
995.
To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 × 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.  相似文献   
996.
Background: Breast cancer is the commonest cancer amongst Malaysian women but local survival data are scarce. The present study was therefore conducted to assess overall survival and prognostic factors in Malaysian breast cancer patients. Methods: The research sample was a prospective cohort of 413 patients diagnosed with breast cancer in the University of Malaya Medical Centre between 1993 to 1997. Survival data were obtained from the National Registry of Birth and Deaths in December 2000. The clinico-pathological variables studied were age, ethnic group, stage, tumour size, lymph node status, oestrogen receptor status and grade. The data were analysed utilizing Splus statistical software. The important prognostic factors were identified by fitting the Cox's proportional hazard model to the data set. Survival probabilities were estimated using the Kaplan-Meier method and differences were compared by the log-rank test. Results: The overall 5-year survival was 59.1%. The Cox's proportional hazard model identified stage, lymph node status, size and grade as factors that correlated with prognosis. Age was not a significant prognostic factor. The Cox regression model by stepwise selection showed stage, nodal status and grade of tumour to be independent prognostic factors, whereas ethnicity, age and ER status were not. Interpretation: The overall survival in our centre was low. Recognizing factors that affect prognosis of breast cancer patients in Malaysia may improve delivery of health care to at-risk groups by strategizing interventions as survival depends on early detection and effective treatment.  相似文献   
997.
Background: Breast cancer is the most common malignant tumor in females. Many studies have been carried out in order to assess the reproductive risk factors. Particular attention has focused on information regarding fertility, including breastfeeding, age at first birth and number of live births. These factors are highly correlated with each other. The objective of this study was to employ latent variables to reduce the confounding effect of this correlation with a logistic regression analysis. Methods: The investigation drew upon results from a dataset belonged to a hospital based case-control study covering 303 breast cancer patients and 303 hospital controls. Data were collected through interview and reproductive variables included age at first full-term pregnancy and live birth, number of pregnancies and live births, and total length of breast feeding. Latent variables were generated using factor analysis and principal components analysis. Results: The study revealed that for both latent variable approaches the odds ratios of two latent variables significantly indicated a protective impact of number of pregnancy and live birth and breastfeeding and a prognostic relation with age at first pregnancy or live birth. Conclusion: The findings suggest that breastfeeding and decreasing age at first live birth have protective influences on breast cancer risk. Also using statistical model with latent variables in the presence of collinear data leads to reliable results.  相似文献   
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999.
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Our objective was to characterize the etiologic factors and outcome for stroke in children. We retrospectively reviewed the charts of patients between the ages of 40 days and 94 months (36.5 +/- 23.7 months) with stroke seen at Istanbul Medical Faculty, Department of Pediatrics between January 1995 and December 2003. We found 79 cases of stroke: 57 ischemic and 22 hemorrhagic strokes. Seventeen children had vitamin K deficiency dependent hemorrhage. In 14 children stroke occurred as a complication of cardiac disease, 7 had moyamoya disease, 3 had protein C deficiency, 2 had thalassemia, 2 had hyperhomocysteinemia (methylene tetrahydrofolate reductase gene mutation), 2 were heterozygote for factor V Leiden, 3 had Down's syndrome, 1 was diagnosed with antiphospholipid syndrome, 1 had glycogen storage disease, and in 28 children no underlying cause could be found. Multiple risk factors were found in 4 children. The outcome in all 79 stroke patients was as follows: asymptomatic 60%; symptomatic epilepsy or persistent neurologic deficit 37%; death 3%; and recurrent stroke 5%. Thus, an underlying cause for stroke was identified in 65% of the children in the study group; 40% of the children either died or suffered motor and/or cognitive sequelae.  相似文献   
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