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71.
PURPOSE.  The purpose of this article is to review relevant background literature regarding the evidence linking thimerosal-containing vaccine and the measles, mumps, and rubella vaccine to autism.
CONCLUSIONS.  Rigorous scientific studies have not identified links between autism and either thimerosal-containing vaccine or the measles, mumps, and rubella vaccine.
PRACTICE IMPLICATIONS.  Nurses are often in the position of providing advice regarding vaccines in their formal practice areas as well as in their daily lives. Families need current and credible evidence to make decisions for their children. Excellent vaccine information resources are available online.  相似文献   
72.
Spirituality plays a vital role in adjusting to chronic illness and rehabilitation nurses strive to gain understanding of their patients' spirituality in order to improve patient care and outcomes. The purpose of this qualitative study was to explore the nature of spirituality in chronically ill rural dwellers and how it relates to their illness. As a part of this pilot project, 10 women with chronic illness volunteered to participate in a phone interview to discuss their spirituality. Content analysis was used to analyze the data. The theme Means the World to Me described what spirituality meant to participants. The following themes described how spirituality related to chronic illness: I Am Not Alone, Putting on a Happy Face, Others Are Worse Off, Transcending Despair and Letting Go. Participants were able to use spiritual coping measures to transcend despair. Results from this study provide rehabilitation nurses with insight into the spirituality needs of chronically ill rural-dwelling women.  相似文献   
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This article describes the development of the Index of Training Need (ITN), a new system for measuring levels of treatment training need. By incorporating self- reported measures of the adequacy of respondents' previous treatment training and respondents' interest in future training in core domains, the ITN system yields a practical guide for the allocation of training resources. In addition, by quantifying levels of training need, the ITN system permits comparisons of training need on a variety of levels. By using the ITN system, educators can identify the needs of substance abuse clinicians efficiently and apply resources cost-effectively. Although this study represents a new approach for assessing training need in the substance abuse treatment field, the ITN approach is not limited to this application. Researchers, policy makers, and educators in other areas can apply the ITN methodology to needs assessment studies in their areas, substituting the appropriate core domains for those used in this study.  相似文献   
75.
Adolescents frequenting indoor tanning facilities may have an increased risk of skin cancer. The high level of indoor tanning by this age group may be due, in part, to the large number of tanning facilities in US cities. This study examined how facilities are distributed throughout one large county. Based on ecological models, it was predicted that tanning facilities are more likely to be located within certain neighborhoods based on the neighborhood’s distributions of demographic factors, including income, educational attainment, race/ethnicity, age, and sex. We also explored whether selected aspects of the built environment, including the numbers of high schools and fitness centers, would predict the number of tanning facilities. The number of tanning facilities within 605 census tracts of San Diego County was examined through geographic information systems mapping. Results from multivariate Poisson log-linear regression indicated that higher numbers or proportions of the following variables within a census tract were significantly, positively correlated with the number of tanning facilities: fitness centers, teenagers 15–19 years, females 15–24 years, females 25–29 years, and non-Hispanic Whites. Results from additional analyses using a 1000-foot buffer zone around each census tract boundary showed that higher relative distributions of the following variables were significantly, positively correlated with the number of tanning facilities: high schools, fitness centers, females 15–24 years, females 25–29 years, and non-Hispanic Whites. These findings suggest a relationship exists between the numbers of tanning facilities and certain built-environmental and demographic characteristics within census tracts. Determining this relationship is important for developing future interventions.  相似文献   
76.

Background

We studied the expression of some major proteins involved in cell-cycle regulation and DNA repair, the roles of which are not well known in pancreatic ductal adenocarcinoma (PDAC), but which have a significant impact on carcinogenesis of many other cancers.

Methods

We immunohistochemically assessed expression levels of the cell-cycle regulators Rb1, p16 and cyclin-dependent kinase 4 (CDK4), and the DNA repair enzymes O6-methylguanine-DNA-alkyltransferase (MGMT) and flap endonuclease-1 (FEN1) separately in malignant tissue and benign tissue from resection margins in 102 cases of PDAC. Nearly all (95.1%) patients had undergone pancreaticoduodenectomy.

Results

The studied proteins showed wide but somewhat variable expression in both benign and malignant pancreatic tissues. Strong CDK4 expression in islets of Langerhans predicted poor relapse-free survival (RFS) (HR 2.874; 95% CI 1.261–6.550; p?=?.012) and within T3–4 tumors CDK4 expression in adenocarcinoma cells also predicted poor disease-free survival (DFS) (RR 2.148; 95% CI 1.081–4.272; p?=?.029). Strong MGMT expression was associated in N1 patients with weak local relapse-free survival (RFS), DFS and overall survival; all significantly in Cox regression analysis. FEN1 was also an independent predictor of decreased DFS (in the whole study population) and worse RFS (in the patients with T3–4 tumors).

Conclusions

Major cell-cycle regulator also have predictive significance, but further studies are required to evaluate this.  相似文献   
77.
Thyroid hormone (TH) plays a fundamental role in thermoregulation, yet the molecular mediators of its effects are not fully defined. Recently, skeletal muscle (SKM) uncoupling protein (UCP) 3 was shown to be an important mediator of the thermogenic effects of the widely abused sympathomimetic agents 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) and methamphetamine. Expression of UCP3 is regulated by TH. Activation of UCP3 is indirectly regulated by norepinephrine (NE) and is dependent upon the availability of free fatty acids (FFAs). We hypothesized that UCP3 may be a molecular link between TH and hyperthermia, requiring increased levels of both NE and FFAs to accomplish the thermogenic effect. Here, we demonstrate that MDMA (40 mg/kg s.c.) significantly increases plasma FFA levels 30 min after treatment. Pharmacologically increasing NE levels through the inhibition of phenylethanolamine N-methyltransferase with +/-2,3-dichloro-alpha-methylbenzylamine potentiated the hyperthermic effects of a 20 mg/kg dose of MDMA. Using Western blots and regression analysis, we further illustrated that chronic hyperthyroidism in rats potentiates the hyperthermic effects of MDMA and increases levels of SKM UCP3 protein in a linear fashion according to levels of circulating plasma TH. Conversely, chronic hypothyroidism results in a hypothermic response to MDMA that is directly proportionate to decreased UCP3 expression. Acute TH supplementation did not change the skeletal muscle UCP3 expression levels or temperature responses to MDMA. These findings suggest that, although MDMA-induced hyperthermia appears to result from increased NE and FFA levels, susceptibility is ultimately determined by TH regulation of UCP3-dependent thermogenesis.  相似文献   
78.
The blood-clotting protein fibrinogen has been implicated in host defense following Staphylococcus aureus infection, but precise mechanisms of host protection and pathogen clearance remain undefined. Peritonitis caused by staphylococci species is a complication for patients with cirrhosis, indwelling catheters, or undergoing peritoneal dialysis. Here, we sought to characterize possible mechanisms of fibrin(ogen)-mediated antimicrobial responses. Wild-type (WT) (Fib+) mice rapidly cleared S. aureus following intraperitoneal infection with elimination of ∼99% of an initial inoculum within 15 min. In contrast, fibrinogen-deficient (Fib–) mice failed to clear the microbe. The genotype-dependent disparity in early clearance resulted in a significant difference in host mortality whereby Fib+ mice uniformly survived whereas Fib– mice exhibited high mortality rates within 24 h. Fibrin(ogen)-mediated bacterial clearance was dependent on (pro)thrombin procoagulant function, supporting a suspected role for fibrin polymerization in this mechanism. Unexpectedly, the primary host initiator of coagulation, tissue factor, was found to be dispensable for this antimicrobial activity. Rather, the bacteria-derived prothrombin activator vWbp was identified as the source of the thrombin-generating potential underlying fibrin(ogen)-dependent bacterial clearance. Mice failed to eliminate S. aureus deficient in vWbp, but clearance of these same microbes in WT mice was restored if active thrombin was administered to the peritoneal cavity. These studies establish that the thrombin/fibrinogen axis is fundamental to host antimicrobial defense, offer a possible explanation for the clinical observation that coagulase-negative staphylococci are a highly prominent infectious agent in peritonitis, and suggest caution against anticoagulants in individuals susceptible to peritoneal infections.

In addition to serving as a centerpiece of hemostasis and thrombosis, fibrin(ogen) directs local inflammation in areas of tissue damage. Fibrin(ogen) can engage an array of integrin and nonintegrin cell-surface receptors to mediate downstream effector functions of innate immune cells. Whereas fibrin(ogen)-driven inflammation is detrimental in the context of inflammatory diseases like arthritis, colitis, and musculoskeletal disease (14), it is an important component of host defense in the context of infection (58). To help counter host defense mechanisms, bacteria have evolved virulence factors that engage host hemostatic system components to manipulate the activity of coagulation and fibrinolytic factors. This is particularly true for staphylococcal species, including the common, highly virulent human pathogen Staphylococcus aureus.S. aureus is a Gram-positive pathogen that expresses numerous virulence factors that engage the hemostatic system within vertebrate hosts, including an array of products that directly bind fibrin(ogen) and control fibrin deposition (913). S. aureus produces two nonproteolytic prothrombin activators, collectively termed “coagulases,” that bind host prothrombin and mediate fibrin formation (14, 15). Pathogen-mediated fibrin(ogen) binding and fibrin formation have been linked to S. aureus functioning as a causative agent underlying a spectrum of diseases ranging from skin infections to life-threatening pneumonia, bacteremia/sepsis, and endocarditis. A possible exception may be peritonitis. Peritoneal infection is particularly problematic for cirrhotic patients, and in hospital-acquired infections is associated with sutures, catheters, and medical implants. Intriguingly, it is coagulase-negative staphylococci (CoNS) that account for the overwhelming majority of these infections (1620). The basis for the high prevalence of CoNS rather than the more pathogenic coagulase-positive S. aureus, and whether there is a functional link to bacterial-driven prothrombin activation, remains undefined. Here, we explored the hypothesis that host fibrinogen and prothrombin drive a bacterial killing mechanism and defined the contribution of bacterial coagulases to infection in a murine model of acute S. aureus peritonitis.  相似文献   
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