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Objectives. We examined associations of individual, psychosocial, and social factors with unprotected anal intercourse (UAI) among young men who have sex with men in New York City.Methods. Using baseline assessment data from 592 young men who have sex with men participating in an ongoing prospective cohort study, we conducted multivariable logistic regression analyses to examine the associations between covariates and likelihood of recently engaging in UAI with same-sex partners.Results. Nineteen percent reported recent UAI with a same-sex partner. In multivariable models, being in a current relationship with another man (adjusted odds ratio [AOR] = 4.87), an arrest history (AOR = 2.01), greater residential instability (AOR = 1.75), and unstable housing or homelessness (AOR = 3.10) was associated with recent UAI. Although high levels of gay community affinity and low internalized homophobia were associated with engaging in UAI in bivariate analyses, these associations did not persist in multivariable analyses.Conclusions. Associations of psychosocial and socially produced conditions with UAI among a new generation of young men who have sex with men warrant that HIV prevention programs and policies address structural factors that predispose sexual risk behaviors.Young men who have sex with men (MSM) continue to be at increased risk for the acquisition and transmission of HIV. Nationally, among those aged 13 to 24 years, the estimate of new HIV infections attributed to male-to-male sexual contact increased from 61% in 2006 to 71% in 2009.1 In New York City between 2001 and 2008, 73% of HIV diagnoses among male adolescents and young adults were among young MSM.2 These national and local surveillance data confirm that a third generation of MSM, a generation that did not witness the heightened morbidity and mortality of the early AIDS epidemic, continue to bear a disproportionate burden of HIV/AIDS. In addition to these epidemiological trends, adolescents and young adults are at heightened risk for HIV/AIDS because the periods of adolescence and young adulthood are marked by a higher prevalence of HIV-related risk behaviors such as unprotected sex and illicit drug use.3,4 Moreover, these periods are often characterized by significant transitions and challenges for young MSM, specifically around the formation of sexual identity as well as coming out to family members and peers that may all coalesce to increase vulnerability for HIV.To date, research related to HIV risk among MSM, and more specifically young MSM, has generally focused on understanding the influence of individual-level characteristics on risk-taking behaviors. For example, it is well established that factors such as educational attainment,5 race/ethnicity,6–8 sexual orientation,9 age at sexual onset,8,10 and relationship status11,12 are associated with sexual risk-taking behaviors, such as engaging in unprotected anal intercourse (UAI). In addition, previous research indicates that those with a history of arrest and incarceration are more likely to engage in greater sexual risk behaviors than are those without such a history.13,14More recently, research efforts have moved beyond examining individual-level characteristics by considering both protective and harmful psychosocial states that may either buffer against or exacerbate vulnerabilities that function as drivers of HIV-related sexual risk behaviors.15,16 For instance, experiences of homophobia can often lead to discomfort with one’s sexual identity and may act as a significant psychosocial stressor linked to increased sexual risk taking.17,18 Conversely, young MSM with positive attitudes about homosexuality are less likely to have multiple sex partners and may be less likely to engage in UAI.19 Finally, gay community affiliation may function to either protect against or exacerbate the risk for HIV transmission and acquisition.Exposure and access to gay neighborhoods with norms promoting safer sexual behaviors may lead to safer sexual practices, such as consistent condom use, among MSM20 as well as greater awareness about HIV education and services available to MSM.21 However, higher gay community affinity among a younger generation of MSM may be associated with greater sexual risk taking in the absence of norms promoting safer sexual behaviors.22Increasingly, empirical research has examined the impact of social factors for their association with sexual risk taking among MSM overall.23 For example, several studies have linked poverty and economic disadvantage as socially produced risk factors associated with sexual risk taking among MSM.24,25 These associations may be more pronounced among individuals with higher levels of residential or housing instability or homelessness because they may engage in sex work to secure vital material resources and therefore be at an increased risk for HIV transmission and acquistion.24,26–28 Because of the need to understand the effect of individual, psychosocial, and social factors on HIV risk among young MSM, we sought to characterize how these factors influence sexual risk behaviors, specifically UAI, in a sample of young MSM. These findings have the potential to inform novel HIV/AIDS-related prevention and intervention efforts for this new generation of men.  相似文献   
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This study investigated the role of incarceration in HIV/STD risk among 197 Black men who have sex with men in Massachusetts, USA. More than half (51%) reported a history of incarceration (28% 相似文献   
45.

Background

Although classroom quality is an important consideration, few recent research studies have examined the process and structural quality in publicly funded early childhood education (ECE) and inclusive ECE classrooms. This study provides an important contribution to the literature by comparing two conceptualizations of quality in classrooms serving children from low-income households and those with disabilities.

Objectives

(1) To characterize and to determine differences with regard to process and structural quality in publicly funded ECE and inclusive ECE classrooms, and (2) to examine whether and to what extent the process quality varied when controlling for structural quality and classroom income/race variables.

Method

One hundred and sixty four classrooms (85 ECE, 79 inclusive) that were enrolled in two large-scale intervention studies examining a book-reading program were included in the present study. The Classroom Assessment Scoring System (CLASS; Pianta et al. in Classroom assessment scoring system, Paul H. Brookes, Baltimore, 2008) and three detailed questionnaires were used to quantify process and structural quality, respectively.

Results

Results revealed quantitative differences in process quality, specifically in the emotional support dimension of negative climate as well as all dimensions of instructional support, between the two settings. In addition, teachers’ education was a significant predictor of process quality, and publicly funded ECE classrooms scored over two points higher on the instructional support domain of the CLASS when controlling for other structural quality measures and income and race.

Conclusions

Our findings have implications for best practice guidelines and policies, particularly for classroom environments serving children with disabilities, which are discussed.
  相似文献   
46.

Rationale

Glia, including astrocytes and microglia, can profoundly modulate neuronal function and behavior; however, very little is known about the signaling molecules that govern neuronal–glial communication and in turn affect behavior. Morphine treatment activates microglia and astrocytes in the nucleus accumbens (NAcc) to induce the synthesis of cytokines and chemokines, and this has important implications for addictive behavior. Blocking morphine-induced glial activation using the nonspecific glial inhibitor, ibudilast, has no effect on the initial rewarding properties of morphine, but completely prevents the relapse of drug-seeking behavior months later.

Objectives

We sought to determine the cellular source of these cytokines and chemokines in the NAcc in response to morphine, and the cell-type-specific expression pattern of their receptors to determine whether neurons have the capacity to respond to these immune signals directly.

Methods

We used fluorescence-activated cell sorting of neurons (Thy1+), astrocytes (GLT1+), and microglia (CD11b+) from the NAcc for the analysis of cell type specific gene expression following morphine or saline treatment.

Results

The results indicate that microglia and neurons each produce a subset of chemokines in response to morphine and that neurons have the capacity to respond directly to a select group of these chemokines via their receptors. In addition, we provide evidence that microglia are capable of responding directly to dopamine release in the NAcc.

Conclusions

Future studies will examine the mechanism(s) by which neurons respond to these immune signals produced by microglia in an effort to understand their effect on addictive behaviors.  相似文献   
47.
During early brain development, microglial activation can negatively impact long-term neuroimmune and cognitive outcomes. It is well-known that significant alcohol exposure during early gestation results in a number of cognitive deficits associated with fetal alcohol spectrum disorders (FASD). Additionally, microglia are activated following high levels of alcohol exposure in rodent models of FASD. We sought to examine whether moderate prenatal alcohol exposure (70 mg/dL blood alcohol concentration) activates microglia in the fetal rat brain, and whether moderate fetal alcohol exposure has long-term negative consequences for immune function and cognitive function in the rat. We also measured inflammation within the placenta and maternal serum following moderate alcohol exposure to determine whether either could be a source of cytokine production in the fetus. One week of moderate prenatal alcohol exposure produced a sex-specific increase in cytokines and chemokines within the fetal brain. Cytokines were also increased within the placenta, regardless of the sex of the fetus, and independent of the low levels of circulating cytokines within the maternal serum. Adult offspring exposed to alcohol prenatally had exaggerated cytokine production in the brain and periphery in response to lipopolysaccharide (25 μg/kg), as well as significant memory deficits precipitated by this low-level of inflammation. Thus the immune system, including microglia, may be a key link to understanding the etiology of fetal alcohol spectrum disorders and other unexplored cognitive or health risks associated with even low levels of fetal alcohol exposure.  相似文献   
48.
Objective. To assess course instructors' and students' perceptions of the Educating Pharmacy Students and Pharmacists to Improve Quality (EPIQ) curriculum.Methods. Seven colleges and schools of pharmacy that were using the EPIQ program in their curricula agreed to participate in the study. Five of the 7 collected student retrospective pre- and post-intervention questionnaires. Changes in students' perceptions were evaluated to assess their relationships with demographics and course variables. Instructors who implemented the EPIQ program at each of the 7 colleges and schools were also asked to complete a questionnaire.Results. Scores on all questionnaire items indicated improvement in students' perceived knowledge of quality improvement. The university the students attended, completion of a class project, and length of coverage of material were significantly related to improvement in the students' scores. Instructors at all colleges and schools felt the EPIQ curriculum was a strong program that fulfilled the criteria for quality improvement and medication error reduction education.Conclusion The EPIQ program is a viable, turnkey option for colleges and schools of pharmacy to use in teaching students about quality improvement.  相似文献   
49.
Cognitive decline is a common problem of aging. Whereas multiple neural and glial mechanisms may account for these declines, microglial sensitization and/or dystrophy has emerged as a leading culprit in brain aging and dysfunction. However, glial activation is consistently observed in normal brain aging as well, independent of frank neuroinflammation or functional impairment. Such variability suggests the existence of additional vulnerability factors that can impact neuronal-glial interactions and thus overall brain and cognitive health. The goal of this review is to elucidate our working hypothesis that an individual’s risk or resilience to neuroinflammatory disorders and poor cognitive aging may critically depend on their early life experience, which can change immune reactivity within the brain for the remainder of the lifespan. For instance, early-life infection in rats can profoundly disrupt memory function in young adulthood, as well as accelerate age-related cognitive decline, both of which are linked to enduring changes in glial function that occur in response to the initial infection. We discuss these findings within the context of the growing literature on the role of immune molecules and neuroimmune crosstalk in normal brain development. We highlight the intrinsic factors (e.g., chemokines, hormones) that regulate microglial development and their colonization of the embryonic and postnatal brain, and the capacity for disruption or “re-programming” of this crucial process by external events (e.g., stress, infection). An impact on glia, which in turn alters neural development, has the capacity to profoundly impact cognitive and mental health function at all stages of life.  相似文献   
50.
Hospital preparedness for nosocomial or community-wide outbreaks of communicable disease includes the capability for rapid, self-reliant administration of prophylaxis to its workforce, with the goal of minimal disruption of patient care, here called hospital "self-prophylaxis." We created a new discrete-event simulation model of a hypothetical hospital wing to compare the operational charateristics of standard single-line, "first-come, first-served" dispensing clinics with those of 2 staff management strategies that can dramatically reduce staff waiting time while centralizing dispensing around existing pharmacy-distribution points.  相似文献   
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