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101.
OBJECTIVE: To examine the effects of race/ethnicity, language, and potential access on parents' reports of pediatric primary care experiences. DATA SOURCES/STUDY SETTING: Primary survey data were collected (67 percent response rate) from 3,406 parents of students in kindergarten through sixth grade in a large urban school district in California during the 1999-2000 school year. DATA COLLECTION: The data were collected by mail, telephone, and in person. Surveys were administered in English, Spanish, Vietnamese, and Tagalog. STUDY DESIGN: Data were analyzed using multiple regression models. The dependent variable was parents' reports of primary care quality, assessed via the previously validated Parents' Perceptions of Primary Care measure (P3C). The independent variables were race/ethnicity, language, and potential access to care (insurance status, presence of a regular provider of care), controlling for child age, gender, and chronic health condition status, and mother's education. PRINCIPAL FINDINGS: Parents' reports of primary care quality varied according to race/ethnicity, with Asian and Latino parents reporting lower P3C scores than African Americans and whites. In multivariate analyses, both language and potential access exerted strong independent effects on primary care quality, reducing the effect of race/ethnicity such that the coefficient for Latinos was no longer significant, and the coefficient for Asians was much smaller, though still statistically significant. CONCLUSIONS: To reduce racial/ethnic disparities in primary care, attention should be paid both to policies aimed at improving potential access and to providing linguistically appropriate services.  相似文献   
102.
The diagnosis of a child's life-shortening disease leads many American parents to utilize religious beliefs. Models relating religious constructs to health have been proposed. Still lacking are inductive models based on parent experience. The specific aims of this study were: 1. develop a grounded theory of parental use of religion in the year after diagnosis; 2. describe whether parents understand a relationship between their religious beliefs and their follow-through with their child's at-home treatment regimen. Fifteen parent interviews were analyzed using grounded theory method. Parents used religion to make meaning of their child's cystic fibrosis (CF) diagnosis. Parents imagined God as active, benevolent, and interventionist; found hope in their beliefs; felt supported by God; and related religion to their motivation to adhere to their child's treatment plan. Religious beliefs are clinically significant in working with many parents of children recently diagnosed with CF. Interventions that improve adherence to treatment may be enhanced by including religious aspects.  相似文献   
103.
Parents of children diagnosed with cystic fibrosis described it as “devastating.” Given religion's importance to many Americans, parents may utilize religious coping. Relatively little is known about parents' use of religious coping to handle their child's illness. Interviews with 15 parents about their use of religion in the year following their child's cystic fibrosis diagnosis were coded for religious coping styles. Sixteen styles were identified. Positive religious coping styles were more frequent than negative styles (previously associated with poorer health outcomes), and occurred more frequently than in other studies. Religious coping styles used to make meaning, gain control, or seek comfort/intimacy with God were equally prevalent. The most common styles were: Pleading, Collaboration, Benevolent Religious Reappraisals, and Seeking Spiritual Support. Parents described active rather than passive coping styles. Religious coping involving religious others was rare. Clinical attention to negative religious coping may prevent it becoming chronic and negatively affecting health.  相似文献   
104.
Currently, more than half of the world's population has no immunity against smallpox variola major virus. This phase I double-blind, randomized trial was conducted to compare the safety and immunogenicity of two clonally derived, cell-culture manufactured vaccinia strains, ACAM1000 and ACAM2000, to the parent vaccine, Dryvax®. Thirty vaccinia-naïve subjects were enrolled into each of three groups and vaccines were administered percutaneously using a bifurcated needle at a dose of 1.0 × 108 PFU/mL. All subjects had a primary skin reaction indicating a successful vaccination. The adverse events, 4-fold neutralizing antibody rise and T cell immune responses were similar between the groups.  相似文献   
105.
Limited joint mobility is frequently observed in elderly people and in patients suffering from diabetes, who represent a growing segment of the population of western countries. Our review wishes to offer the state of art about this interesting topic, which may have important clinical implications, leading to impairment of both basic and instrumental activities of daily living. The main causes of a reduced range of motion are degenerative joint diseases and increased stiffness of collagen tissue. The main biochemical abnormality, common to aging and diabetes, is the non-enzymatic glycosilation of collagen, with advanced glycation end product (AGE) formation, which in turn leads to an increase of collagen cross-links. The most extensive accumulation of AGEs occurs in tissues that contain proteins with low turnover, such as the collagen in the extracellular matrix of articular capsule, ligaments and muscle-tendon units. The increase in collagen cross-linking alters the mechanical properties of these tissues with a decrease in elasticity and tensile strength, and an increase in mechanical stiffness. Besides this, AGEs react with specific cell surface receptors (RAGEs). The engagement of the ligand by RAGEs triggers cell-specific signalling, resulting in enhanced generation of reactive oxygen species and sustained up-regulation of pro-inflammatory mediators and adhesion molecules. An appropriate control of the glucose levels and a diet rich in antioxidant agents are recommended in patients with diabetes. Stretching and strengthening programmes are widely used, in order to prevent and to reduce joint stiffness, but the improvements with physiotherapy are little and short-lasting. Several drugs, which can interfere with AGE formation and removal, or with the cellular effects of AGEs, are under study (among them pyridoxamine, an active form of Vitamin B6, AGE-breaker compounds, glucosamine, rutin and derivatives, soluble RAGE isoforms, and statins). In experimental animal models, these drugs are effective in reducing diabetic complications due to AGE formation; however, further study is necessary before their extensive use in the clinical setting.  相似文献   
106.
    
Post-installed rebars (PIRs) using mortar can offer bond strength at ambient temperature equal or higher to that of cast-in place rebars. However, high temperatures have the effect of weakening the bond, typically governed by the chemical and physical properties of the mortar which is often sensitive to temperature increase. Therefore, the behavior of PIRs in a fire situation becomes vulnerable. Moreover, after exposure of PIRs to high temperature, the heat transfer continues during the post-fire phase, which might endanger the construction after a fire event. In order to evaluate the evolution of the pull-out capacity during fire, Pinoteau et al. have developed the bond resistance integration method (Pinoteau’s RIM) to predict the bond resistance value of a rebar subjected to various temperatures in accordance with the fire exposure curves. Therefore, accurate temperature profiles during the post-fire phase are needed to ensure a correct calculation of the post-fire behavior of the PIR connection. This paper presents 3D finite element thermal simulations of PIRs in concrete exposed to ISO 834-1 fire conditions then cooled with ambient air. Numerical thermal profiles are then compared to the experimental results (i.e., post-fire pull-out tests). The proposed model provides guidelines for conducting numerical simulations to determine the thermal entry data necessary for predicting thermal profiles in PIRs during heating and cooling phases. Then, the post-fire pull-out capacity of PIRs in concrete is calculated using Pinoteau’s RIM, and compared to experimental post-fire pull-out results.  相似文献   
107.
108.
Intense myocardial uptake of Tc-99m-MDP in a case of hypercalcemia   总被引:1,自引:0,他引:1  
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109.
110.
The degradation of four aromatic thermoplastics containing carbonyl, ether and sulfone linkages was performed in a thermogravimetric analyzer in both nitrogen and air environments, in isothermal and dynamic heating conditions. The obtained results suggest that degradations started by random chain scission under all the experimental conditions. Under N2 flow branching and crosslinking were superimposed on the initial process, while in air complete oxidative degradation occurred. The apparent activation energies associated with the first degradation stage were evaluated and correlated with the linkages present in the polymer chains. The obtained values indicate that the chemical reactions occurring under nitrogen are different from those in air. In addition, the ratio of the chain scission rate to the branching and crosslinking rates in nitrogen is dependent on temperature in isothermal experiments and on heating rate in the dynamic ones. A comparison with poly(ether ether ketone) is also reported.  相似文献   
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