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101.
Objectives: To compare maternal characteristics and birth outcomes of Mexico-born and native-born mothers in the United States and those of North African mothers living in France and Belgium to French and Belgian nationals. Methods: We examined information from single live birth certificates for 285,371 Mexico-born and 3,131,632 U.S.-born mothers (including 2,537,264 U.S.-born White mothers) in the United States, 4,623 North African and 103,345 Belgian mothers in Belgium, and a French national random sample consisting of 632 North African and 11,185 French mothers. The outcomes were mean birthweight, low birthweight, and preterm births. Differences between native/nationals and foreign-born mothers in each country were assessed in bivariate and multivariate analyses controlling for maternal risk factors. Results: The adjusted odds for low birthweight were lower for immigrants than native/nationals by 32% in the United States, by 32% in Belgium, and by 30% in France. The adjusted odds for preterm births were lower for immigrants compared with native/nationals by 11% in the United States and by 23% in Belgium. In France, the odds for preterm births were comparable for immigrants and naturalized mothers. Infants of immigrant mothers also had higher mean birthweights in all three countries. Conclusion: Despite their disadvantaged status, Mexico-born and North African-born women residing in the United States, France, and Belgium show good birth outcomes. These cannot be explained solely by traditional risk factors. Protective factors and selective migration may offer further clues.  相似文献   
102.
With increasing pressure from third-party payers to assess client outcomes, clinical programs want to know how to implement outcome systems. This article focuses on practical and logistic questions involved in implementing an outcome assessment system in ambulatory behavioral healthcare settings. Study questions addressed outcome systems in general and the use of the Behavior and Symptom Identification Scale (BASIS-32) and the Short Form Health Status Profile (SF-36) in particular. General questions focused on obtaining provider buy-in, client consent and confidentiality, data collection methods, sampling, time points, maximizing client participation, clinical utility of outcome data, and resources needed for outcome assessment. Measure-specific questions focused on client acceptability of the instruments and applicability of measures to diverse populations. The article suggests several strategies for enhancing outcome assessment efforts and concludes that there remains a need for further understanding of ways to maximize the utility and value of outcome measurement.  相似文献   
103.
Irreducible knee dislocation is a rare injury. This case report describes a knee dislocation in a 39-year-old male U.S. Army noncommissioned officer who was injured while playing in a softball game. Arthroscopy showed the medial collateral ligament and capsule to be locked in the intercondylar notch, covering the medial femoral condyle. Arthrotomy and open reduction were required. Staged posterior cruciate ligament reconstruction using patellar tendon autograft was later performed. Review of the magnetic resonance imaging scan showed the irreducible lesion. The diagnostic clinical and radiographic features of this unusual injury are described.  相似文献   
104.
BACKGROUND: Focal osteolysis due to ultra-high molecular weight polyethylene wear debris involves effects on both bone resorption and bone formation. METHODS: The response of MG63 osteoblast-like osteosarcoma cells to ultra-high molecular weight polyethylene wear debris isolated by enzymatic digestion of granulomatous tissue obtained from the sites of failed total hip arthroplasties was examined. Scanning electron microscopy, particle-size analysis, and Fourier transform infrared spectroscopy were used to characterize the number, morphology, size distribution, and chemical composition of the particles. Cell response was assessed by adding particles at varying dilutions to confluent cultures and measuring changes in cell proliferation (number of cells and [3H]-thymidine incorporation), osteoblast function (alkaline-phosphatase-specific activity and osteocalcin production), matrix production (collagen production and proteoglycan sulfation), and local cytokine production (prostaglandin-E2 production). RESULTS: The mean size of the particles was 0.60 micrometer, and 95 percent of the particles had a size of less than 1.5 micrometers. The number of particles per gram of tissue ranged from 1.39 to 3.38x10(9). Three of the four batches of particles were endotoxin-free. Exposure of the cells to particles of wear debris significantly increased the number of cells (p<0.05) and the [3H]-thymidine incorporation (p<0.05) in a dose-dependent manner. In contrast, the addition of particles decreased alkaline-phosphatase-specific activity and osteocalcin production. Collagen production and proteoglycan sulfation were also decreased, while prostaglandin-E2 synthesis was increased by the addition of particles. CONCLUSIONS: Ultra-high molecular weight polyethylene particles isolated from human tissue stimulated osteoblast proliferation and prostaglandin-E2 production and inhibited cell differentiation and matrix production. These results indicate that particles of wear debris inhibit cell functions associated with bone formation and that osteoblasts may produce factors in response to wear debris that influence neighboring cells, such as osteoclasts and macrophages. CLINICAL RELEVANCE: Particles of wear debris, especially ultra-high molecular weight polyethylene, have been implicated in the loosening of implants and the development of osteolysis. The present study shows that particles of ultra-high molecular weight polyethylene isolated from human tissue inhibit osteoblast functions associated with bone formation. In addition, particles of wear debris induced osteoblasts to secrete factors capable of influencing neighboring cells, such as osteoclasts and macrophages. These results suggest that osteoblasts may play a role in the cascade of events leading to granuloma formation, osteolysis, and failure of orthopaedic implants.  相似文献   
105.
Managed behavioral health care is widely perceived as a threat to traditional practice in mental health at the expense of quality care. Although such assertions by mental health providers may prove to be justified in certain circumstances, they should not serve to obscure the quite reasonable public health motives behind managed care and the favorable effect managed care organizations may ultimately have on clinical decision-making and practice. By compelling practitioners to more clearly articulate the basis for their clinical judgments and by increasingly requiring evidence to support such judgments, they discourage the application of ill-considered, sometimes inappropriate, and occasionally iatrogenic evaluation and treatment interventions. In the future, there is significant danger that developmental assessment and treatment procedures for young children will be inappropriately constrained and diminished. This is especially true if those who work with young children fail to use the tools available to them to make the case for the best of current practice, whether a clearly stated clinical rationale, a formal appeal, the advocacy of our health professions, or applied clinical services research. The practices of our health plans need to be understood by providers in the context of managed care values. Primitive systems should not be confused with corrupt systems. Although undoubtedly the latter exist, they do not necessarily predominate. Within a managed care context and with due respect to managed care assumptions, it is possible to bring utilization management and contemporary practices in developmental assessment into closer alignment, ultimately to the benefit of children who need them.  相似文献   
106.
107.
Evidence-based practice is an important step in the professional evolution of occupational therapy and also provides the means for state-of-the-art innovative clinical service for clients. An essential step in incorporating innovations and developments into clinical practice is through research utilization. Nine models of research utilization developed in the literature are reviewed and critiqued. These are: (1) the Conduct and Utilization of Research in Nursing (CURN) Project; (2) the Stetler-Marram Model; (3) the University of North Carolina Approach; (4) the Innovation Diffusion Process Model; (5) Killeen's Matrix of Research Activity; (6) the Iowa Model of Research In Practice; (7) the Western Interstate Commission for Higher Education In Nursing Project; (8) the Nursing Child Assessment Satellite Training Project; and (9) the Linkage Model. Research utilization models provide a framework for collaboration and the necessary conditions for research utilization activities to be successful. Copyright © 1999 Whurr Publishers Ltd.  相似文献   
108.
In an open trial with 18 healthy male volunteers (21-45 years old) the effect of processed (test) and non-processed (reference) coffee samples of same origin on the gastric potential difference (GPD) was studied. Test coffee samples were processed with the patented "Darboven improvement procedure" before roasting. All treatment groups were subdivided according to the Helicobacter pylori status of the volunteers. The evaluation of the target parameters Reizindex (RI), area under the baseline (AUB), maximum potential difference (Pdmax) and total time (ttot) revealed a significant lower RI (p = 0.0282) and AUB (p = 0.0136), and a significant shorter ttot (p = 0.0286) for the processed coffee. Total cholesterol, high-density lipoprotein (HDL) cholesterol, and pancreatic peptides showed a comparable marked increase of the arithmetic mean with both coffee samples, however, being more intense in the Helicobacter pylori-positive subgroup than in the Helicobacter pylori-negative subgroup. No negative findings concerning tolerability and safety could be seen. In conclusion, the test coffee samples processed with a new method to improve the stomach mucosal irritation-potential of coffee charges revealed a remarkably lower stomach mucosal irritation.  相似文献   
109.
Double rotational-echo double resonance (double REDOR) has been used to investigate the bound conformations of (13)C,(15)N,(19)F-labeled factor Xa inhibitors to bovine trypsin. Carbon-fluorine dipolar couplings were measured by (13)C{(19)F} REDOR with natural-abundance background interferences removed by (13)C{(15)N} REDOR. The conformations of the bound inhibitors were characterized by molecular dynamics (MD) simulations of binding restrained by double REDOR-determined intramolecular C-F distances. A symmetrical bisamidine inhibitor and an asymmetrical monoamidine-monoamine inhibitor of the same general shape had distinctly different conformations in the bound state. According to the MD models, these differences arise from specific interactions of the amidine and amine groups with the active-site residues of trypsin and nearby water molecules.  相似文献   
110.
Sexually maturing female rainbow trout were exposed in the laboratory to 0.01 mg/L and 0.02 mg/L hydrogen cyanide (HCN) for 20 days at 10 ±0.5C. Histological sections of ovaries from these fish indicated abnormal cytoplasmic features among oocytes during their early development. Oocytes exposed to cyanide during late development exhibited altered patterns of secondary yolk deposition. Quantitative observations similarly confirm delays in secondary yolk deposition. Exposure of females to 0.02 mg/L HCN during early summer ovarian growth resulted in delayed secondary yolk deposition among 93% of the oocytes when compared with controls. When fish were exposed during mid-summer, the effects were evident at both concentrations with approximately 60% of the oocytes failing to reach the secondary yolk deposition stage at the completion of the experiment. This was further substantiated by potential growth studies which indicated a complete absence of oocytes in the final stages of secondary yolk deposition at both cyanide concentrations as compared with controls which contained 27%. The high frequency of atresia at both concentrations suggested that oocytes unable to produce secondary yolk were resorbed by the ovary through a unique form of atresia. It is also suggested that levels of cyanide as low as 0.01 mg/L have a critical effect upon the process of secondary yolk deposition within the ovary and thus significantly reduce the number of viable eggs.  相似文献   
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