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91.
Objectives. We examined correlates of love and trust among female sex workers and their noncommercial male partners along the Mexico–US border.Methods. From 2011 to 2012, 322 partners in Tijuana and Ciudad Juárez, Mexico, completed assessments of love and trust. Cross-sectional dyadic regression analyses identified associations of relationship characteristics and HIV risk behaviors with love and trust.Results. Within 161 couples, love and trust scores were moderately high (median 70/95 and 29/40 points, respectively) and correlated with relationship satisfaction. In regression analyses of HIV risk factors, men and women who used methamphetamine reported lower love scores, whereas women who used heroin reported slightly higher love. In an alternate model, men with concurrent sexual partners had lower love scores. For both partners, relationship conflict was associated with lower trust.Conclusions. Love and trust are associated with relationship quality, sexual risk, and drug use patterns that shape intimate partners’ HIV risk. HIV interventions should consider the emotional quality of sex workers’ intimate relationships.While public health interventions continue to be grounded in tenets of risk and disease, there is growing recognition of the importance of emotions such as love and trust in shaping the health behaviors of diverse populations. Unprotected sex allows for transmission of HIV and other sexually transmitted infections (STIs) but often carries emotional meanings of trust and commitment that impede condom negotiation even among individuals with high knowledge and self-efficacy.1–4 Research has consistently found female sex workers’ condom use to be less frequent with their noncommercial male partners than with clients, which has been linked to intimacy, love, and trust.5–7 Similarly, drug-using couples may share syringes and engage in additional known HIV risk behaviors to convey support and emotional closeness.8,9 Although much of this research is qualitative, some quantitative work has confirmed associations between perceptions of intimacy and condom use among sex workers and clients10 and men who have sex with men.11Quantitative researchers have attempted to operationalize emotions into theoretical constructs for empirical research.12 Sternberg’s “triangular” theory posits that love comprises 3 components: intimacy (feelings of emotional closeness between partners), passion (physical attraction and sexual consummation), and commitment (decisions that partners make about maintaining relationships).13,14 Taken together, these components combine to generate different kinds of love.13,15,16Another important aspect of intimate relationships, trust is conceptualized as a belief in the integrity of a partner. Trust may be based on individuals’ assessments of their partners’ benevolence and honesty17 and subjective feelings of security within relationships.18,19 To measure trust quantitatively, Larzelere and Huston developed a dyadic trust scale that correlated with love and relationship quality.17A rich body of ethnographic scholarship has highlighted the importance of companionate relationships and love in diverse global contexts,20–22 but quantification of emotional constructs are largely absent from settings outside the Western middle-class experience. Most quantitative studies of love and trust have focused on privileged populations who do not experience the burden of disease that disproportionately affects socially marginalized couples. Existing studies among US populations have also suggested that women and men value components of these emotions differently,23–25 yet the implications of these potential gender differences for HIV prevention among vulnerable couples remains underexplored.Our study of love and trust among sex workers and their noncommercial partners is situated in 2 Mexican border cities: Tijuana, Baja California, south of San Diego, California (population 1.6 million), and Ciudad Juárez, Chihuahua, adjacent to El Paso, Texas (population 1.3 million). Both cities have areas where sex work and drug use are concentrated,26 lending to the conceptualization of the border as an HIV risk environment27 characterized by poverty, unemployment, violence, and availability of illicit drugs.28 Research has documented substantial overlap in risky sexual and injection drug use behaviors among marginalized female sex workers29 who often turn to sex work as a last option for supporting themselves and their dependents.30Drawing on Connell’s conceptualization of gender as a relational process influenced by structural and sociocultural factors,31 our previous qualitative and ethnographic inquiry into sex workers’ intimate partnerships in these cities proposed that emotions are shaped by the HIV risk environment of the border. Structural conditions bring partners together into relationships that provide critical material and emotional support. In light of limited economic opportunities, couples form tacit agreements regarding women’s engagement in sex work. In the process, women emerge as primary wage earners, alienating men from traditional gender roles as providers and shifting gender dynamics. To cope, partners mostly avoid communicating about sex work or disclosing HIV risk to protect the emotional integrity of the relationship.32We also found that these couples’ relationships range in emotional intensity from friendship and care to transformative experiences of love. Regardless, most couples demarcate their primary relationships from sex work by engaging in unprotected sex. Among couples who inject drugs, sharing syringes together (but not with others) often reinforces trust and care.33 Concerns of mistrust and infidelity also reduced couples’ interest in alternative HIV-prevention technologies such as pre-exposure prophylaxis.34In light of the central role of emotions in our qualitative research with these couples, we attempted to quantify constructs of love and trust and identify associated relationship traits and HIV risk behaviors in our larger cohort. We hypothesized that markers of relationship quality (e.g., higher satisfaction, lower conflict) and unprotected sex within primary relationships would be associated with higher love and trust, whereas extradyadic HIV risk behaviors (e.g., concurrent sexual partners, syringe sharing with others) would be associated with lower love and trust.  相似文献   
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Nearly all countries in the world today are burdened with malnutrition, manifesting as undernutrition, micronutrient deficiencies, and/or overweight and obesity. Despite some progress, efforts to alleviate malnutrition are hampered by a shortage in number, skills, and geographic coverage, of a workforce for nutrition. Here, we report the findings of the Castel Gandolfo workshop, a convening of experts from diverse fields in March 2014 to consider how to develop the capacity of a global cadre of nutrition professionals for the post-2015 development era. Workshop participants identified several requirements for developing a workforce for nutrition, including an ability to work as part of a multisectoral team; communication, advocacy, and leadership skills to engage decision makers; and a set of technical skills to address future challenges for nutrition. Other opportunities were highlighted that could immediately contribute to capacity development, including the creation of a consortium to link global North and South universities, online training modules for middle managers, and practical, hands-on experiences for frontline nutrition workers. Institutional and organizational support is needed to enable workshop recommendations on education and training to be effectively implemented and sustained. The findings from the Castel Gandolfo workshop can contribute to the delivery of successful nutrition-relevant actions in the face of mounting external pressures and informing and attaining the forthcoming Sustainable Development Goals.  相似文献   
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Malaria remains a global public health concern and current treatment options are suboptimal in some clinical settings. For effective chemotherapy, antimalarial drug concentrations must be sufficient to remove completely all of the parasites in the infected host. Optimized dosing therefore requires a detailed understanding of the time course of antimalarial response, whilst simultaneously considering the parasite life cycle and host immune elimination. Recently, the World Health Organization (WHO) has recommended the development of mathematical models for understanding better antimalarial drug resistance and management. Other international groups have also suggested that mechanistic pharmacokinetic (PK) and pharmacodynamic (PD) models can support the rationalization of antimalarial dosing strategies. At present, artemisinin-based combination therapy (ACT) is recommended as first line treatment of falciparum malaria for all patient groups. This review summarizes the PK–PD characterization of artemisinin derivatives and other partner drugs from both preclinical studies and human clinical trials. We outline the continuous and discrete time models that have been proposed to describe antimalarial activity on specific stages of the parasite life cycle. The translation of PK–PD predictions from animals to humans is considered, because preclinical studies can provide rich data for detailed mechanism-based modelling. While similar sampling techniques are limited in clinical studies, PK–PD models can be used to optimize the design of experiments to improve estimation of the parameters of interest. Ultimately, we propose that fully developed mechanistic models can simulate and rationalize ACT or other treatment strategies in antimalarial chemotherapy.  相似文献   
95.
Recent experimental studies have demonstrated extensive biochemical differences between the outer and inner dynein arms of cilia. The inner dynein arms are now emerging as the "prime movers" for ciliary clearance. We studied ciliary motility as evidenced by radioisotope mucociliary clearance, and the ultrastructure of respiratory cilia in a patient with Kartagener's syndrome. Cilia exhibited complete absence of only the inner dynein arms, while retaining outer arms, and mucociliary clearance was totally absent. We also studied neutrophil chemotaxis and other immunologic functions in our patient and found them to be normal. Our findings demonstrate an association between the structural abnormality of absent inner dynein arms alone and ciliary immotility in Kartagener's syndrome. The neutrophil migration abnormalities may have a different mechanism which needs further study.  相似文献   
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The gastric acid response to graded doses of insulin given by continuous infusion was studied in four dogs, each surgically provided with a gastric fistula. All doses of insulin resulted in a prolonged plateau of hypoglycaemia and the degree of hypoglycaemia correlated significantly (p <0.05) with the insulin dose, up to 0.15 u/kg hr. Similarly, graded doses of insulin (up to 0.15 u/kg hr) produced graded acid responses and both the peak acid output and the total acid output correlated significantly with blood glucose changes. No initial inhibitory phase of acid secretion followed the start of the infusion, but a dose-related delay in the onset of the acid response was observed. Our results indicate that insulin provides a quantitative glycopenic stimulus producing a quantitative vagal acid response.  相似文献   
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