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61.
Context.— Inner-city immunization rates have lagged behind those in other areas of the country. Objective.— To evaluate the impact of an initiative linking immunization with distribution of food vouchers in the inner city. Design.— Retrospective analysis of immunization data gathered in 1996 and 1997. Setting.— Nineteen Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) sites serving 30% of the Chicago, Ill, birth cohort. Participants.— A total of 16581 children 24 months old or younger. Interventions.— Voucher incentives (varying frequency of food voucher issuance based on immunization status) and assessment of immunization status and referral to immunization provider. Main Outcome Measures.— Age-appropriate immunization rates and WIC enrollment rates. Results.— During the 15-month period of evaluation, immunization rates increased from 56% to 89% at sites performing voucher incentives. The proportion of children needing voucher incentives declined from 51% to 12%. Sites performing assessment and referral, but not providing voucher incentives, showed no evidence of improvement in immunization coverage. No difference was observed in enrollment rates between sites performing voucher incentives and those that did not. Conclusion.— Applied in a large-scale, programmatic fashion, voucher incentives in WIC can rapidly increase and sustain high childhood immunization rates in an inner-city population.   相似文献   
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Mature human hepatocytes are not suitable for large-scale in vitro applications that rely on hepatocyte function, due to their limited availability and insufficient proliferation capacity in vitro. In contrast, human fetal liver cells (HFLC) can be easily expanded in vitro. In this study we evaluated the hepatic function of HFLCs under proliferative conditions, to determine whether HFLCs can replace mature hepatocytes for in vitro applications. HFLCs were isolated from fetal livers of 16 weeks gestation. Hepatic functions of HFLCs were determined in primary culture and after expansion in vitro. Clonal derivatives were selected and tested for hepatic functionality. Results were compared to primary mature human hepatocytes in vitro. No differences were observed between primary HFLCs and mature human hepatocytes in albumin production and mRNA levels of various liver-specific genes. Ureagenesis was 4.4-fold lower and ammonia elimination was absent in HFLCs. Expanding HFLCs decreased hepatic functions and increased cell stretching. In contrast, clonal derivatives had stable functionality and morphology and responded to differentiation stimuli. Although their hepatic functions were higher than in passaged HFLCs, functionality was at least 20 times lower compared to mature human hepatocytes. HFLCs cannot replace mature human hepatocytes in in vitro applications requiring extensive in vitro expansion, because this is associated with decreased hepatic functionality. Selecting functional subpopulations can, at least partly, prevent this. In addition, defining conditions that support hepatic differentiation is necessary to obtain HFLC cultures suitable for in vitro hepatic applications.  相似文献   
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Background The aim was to investigate the value of adjuvant radiotherapy for locally advanced soft tissue sarcoma after hyperthermic isolated limb perfusion (ILP) with tumor necrosis factor α and melphalan followed by limb-saving surgery. Methods From 1991 to 2003, 73 patients (median age, 54 years; range, 14–80 years) underwent 77 ILPs, followed by resection in 68 patients (93%). Radiotherapy was administered in case of marginally or microscopically positive resection margins. Local recurrences were scored and calculated according to the Kaplan-Meier method and log-rank test. Results After residual tumor mass resection, 58% received radiotherapy (external beam radiotherapy [EBRT]+ group), and 42% did not (EBRT group). The median follow-up was 28 months (range, 2–159 months). A significantly better local control rate was observed in the EBRT+ compared with the EBRT group (P < .0001). When only R0 resections in patients without metastasis were considered, the significance remained between groups (P = .0003). In the EBRT group, an R1 or R2 resection resulted in earlier relapse of local disease compared with R0 resections (P = .0475). Conclusions Adjuvant EBRT reduces the risk for local recurrence after delayed resection in soft tissue sarcoma patients treated with ILP and tumor necrosis factor and is indicated when resection margins are close or microscopically positive. It also seems beneficial after an R0 resection.  相似文献   
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Diabetes and impaired glucose tolerance are largely underdiagnosed in patients with acute atherosclerotic events. This glucose-unawareness is an obstacle for aggressive treatment in these patients. It is suggested to check fasting glucose levels in patients scheduled for cardiovascular surgery and to give intensive insulin therapy perioperatively if fasting glucose levels are greater than 7.0 mmol/L (126 mg/dL). If fasting glucose levels are not elevated an oral glucose tolerance test should be considered so that unknown diabetes can be detected and treated.  相似文献   
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Molecular mobility is increasingly considered a key factor influencing storage stability of biomolecular substances, because it is thought to control the rate of detrimental reactions responsible for reducing the shelf life of, for instance, pharmaceuticals, food, and germplasm. We investigated the relationship between aging rates of germplasm and the rotational motion of a polar spin probe in the cytoplasm under different storage conditions using saturation transfer electron paramagnetic resonance spectroscopy. Rotational motion of the spin probe in the cytoplasm of seed and pollen of various plant species changed as a function of moisture content and temperature in a manner similar to aging rates or longevity. A linear relationship was established between the logarithms of rotational motion and aging rates or longevity. This linearity suggests that detrimental aging rates are associated with molecular mobility in the cytoplasm. By measuring the rotational correlation times at low temperatures at which experimental determination of longevity is practically impossible, this linearity enabled us to predict vigor loss or longevity. At subzero temperatures, moisture contents for maximum life span were predicted to be higher than those hitherto used in genebanks, urging for a reexamination of seed storage protocols.  相似文献   
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Heart-reactive antibody (HRA) appears in the sera of experimental animals inoculated with group A streptococci as well as patients with acute rheumatic fever. Adsorption of either serum with group A streptococcal membranes will remove the HRA. Blocking experiments between these two types of HRAs have demonstrated that the antibodies are directed towards different antigenic determinants on either the same or different molecules. To isolate and purify the antigen from the group A streptococcus cross-reactive with sarcolemmal sheaths of cardiac myofibers, it became necessary to purify the HRA from rheumatic fever patients’ sera. Isolated gamma globulin containing all of the HRA was adsorbed onto human sarcolemmal sheaths. The specific HRA was released by using potassium iodide. Over 99 percent of the purified HRA was shown to bind the sarcolemmal sheath whereas less than 1 percent of the antibody would bind nonspecifically to other material. Preparations of group A streptococcal membrane will bind HRA purified from the sera of acute rheumatic patients at levels of 97 percent or greater. The cross-reactive antigen solubilized by nonionic detergent was purified 120-fold by column chromatography. On sodium dodecyl sulfate polyacrylamide electrophoresis, the antigen was demonstrated to be composed of four polypeptides with mol wt of 32,000, 28,000, 26,000, and 22,000 daltons, respectively. Only proteolytic enzymes could destroy the antigenic determinant whereas glycosidases and lipases had no effect. The purified antigen blocked the binding of purified HRA to normal human heart sections.  相似文献   
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Severe malaria in children in Papua New Guinea   总被引:1,自引:0,他引:1  
The clinical features of severe falciparum malaria and risk factors for mortality were studied in 489 children admitted with malaria to Madang Hospital, Papua New Guinea. The most common severe manifestations of malaria were severe anaemia (22%) and coma (16%). Children with severe anaemia were younger than those with coma (median age 2.2 vs. 3.7 years) and had been ill for longer before admission (median 7 vs. 4 days, respectively). Although the clinical features of coma in Madang children with malaria resembled closely those reported in African children, mortality was lower (8% vs. 17-25%, respectively). Overall, 17 (3.5%) children died, most within 12 h of admission. A high level of plasma lactate (> or = 5 mmol/l) was common (20%) and was the major predictor of death in multiple regression analysis. Raised plasma creatinine and decreased plasma bicarbonate were also independent predictors of mortality. Coma was not predictive of death, although a high proportion of children with profound coma died. Investigation of the causes of acidosis in children with malaria is a high research priority. In view of the short time interval between admission and death in many children, emphasis must be placed on the prevention or early recognition and treatment of acidosis in the district health clinic as well as the central hospital.   相似文献   
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