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1.
Obesity is a modifiable risk factor in breast cancer patients and is predictive of disease outcomes in early-onset breast cancer survivors. The purpose of this review is to summarize the current evidence in the association between early-onset breast cancer and obesity, specifically in African-American women. Reviewing the molecular mechanisms and social determinants of disease in this population can provide a foundation for future interventions in prevention, detection, and treatment aiming at improving outcomes for young breast cancer patients.  相似文献   
2.
The objective was to determine the effects of carbohydrate (CHO) supplementation on exercise-induced hormone responses and post-training intramyocellular lipid stores (IMCL). Twenty-four elite male athletes (28.0 ± 1.2 years) were randomized to receive CHO (maltodextrin solution) or zero energy placebo solution (control group). The high-intensity running protocol consisted of 10 × 800 m at 100% of the best 3000-m speed (Vm3 km) and 2 × 1000 m maximal bouts in the morning and a submaximal 10-km continuous easy running in the afternoon of day 9. IMCL concentrations were assessed by 1H-MRS before (?day 9) and after training (day 9) in soleus (SO) and tibialis anterior (TA) muscles. Blood hormones were also measured before, during, and post-exercise. The percent change (Δ%) in TA-IMCL was higher in the CHO group (47.9 ± 24.5 IMCL/Cr) than in the control group (?1.7 ± 13.1, respectively) (P = .04). Insulin concentrations were higher in the CHO group post-intermittent running compared to control (P = .02). Circulating levels of free fatty acids and GH were lower in the CHO group (P > .01). The decline in performance in the 2nd 1000-m bout was also attenuated in this group compared to control (P < .001 and P = .0035, respectively). The hormonal milieu (higher insulin and lower GH levels) in the CHO group, together with unchanged free fatty acid levels, probably contributed to the increased IMCL stores. This greater energy storage capacity may have improved post-exercise recovery and thus prevented performance deterioration.  相似文献   
3.
Widely recognized problems with the U.S. health care system, including rapidly increasing costs and disparities in access and outcomes also exist in oral health. If oral health systems are to meet the "Triple Aim" of improving the experience of care, improving the health of populations, and reducing per capita costs of health care, new and innovative strategies will be needed including new regulatory, delivery, and financing systems. The virtual dental home is one such system.  相似文献   
4.

Purpose

This study aims to review our experience with central nervous system (CNS) tumors occurring during the first year of life and to report differing features found in our series.

Methods

This is a retrospective study of infants with CNS tumors diagnosed at our institution from 2006 to 2011.

Results

A total of 19 cases were identified, with a median age of 232 days and predominance of male gender. Males were younger than females at the time of diagnosis (p value?=?0.039). There were 13 low-grade tumors, glial tumors being the most common (11/13, p value?=?0.003) and six high-grade tumors, atypical teratoid rhabdoid tumor being the most common (4/6). Low-grade tumors predominated in the supratentorial region, while high-grade tumors were seen in the infratentorial area (p value?=?0.035). Males had a predilection to have more supratentorial tumors (p value?=?0.058). Four patients underwent gross total resection, and eight received chemotherapy; none received radiotherapy. Two patients had spinal cord tumors; both were of pilomyxoid astrocytoma histology. Rare tumors included hemangiopericytoma (n?=?1) and atypical choroid plexus tumor (n?=?1), both occurring in the supratentorial area and affecting the youngest patients in this group; they were diagnosed prenatally and at 107 days, respectively. The median progression-free and overall survivals were 269 and 667 days, respectively. Among all tested parameters, only the grade of the tumor affected the outcome.

Conclusions

Diagnosis and management of infant's CNS tumors remain challenging. Pathologists should be aware of the diversity of histological types. Assigning appropriate tumor grade is fundamental in predicting the outcome.  相似文献   
5.
The house/ball community is an understudied sub-group of young Black men who have sex with men and transgender persons in urban centers of the United States who affiliate in social structures called houses and gather at elaborate dance and performance events called balls. In Charlotte, North Carolina, 12 house/ball members were interviewed about their experiences with health care providers and their assessment of any barriers to care due to their affiliation with the rather clandestine house/ball sub-culture. Additionally, HIV-specific health care providers were interviewed, to assess their knowledge of the sub-culture. House/ball members reported both positive and negative perceptions of treatment by their health care providers with respect to their house/ball involvement. Some reported feeling stigmatized, especially around HIV status. Results showed that increased knowledge about the house/ball community could improve practitioners’ cultural competence, thereby reducing stigma-related barriers to care.  相似文献   
6.
This paper describes imaging findings of splenic lymphangioma in a 59-year-old female patient, together with a critical review of the literature. Lymphangioma exclusively in the spleen in adults is a rare event and, in most cases, it is asymptomatic.  相似文献   
7.
RATIONALE: Environmental stimuli associated with drugs of abuse are believed to play a major role in the motivation to take drugs, drug dependence, and relapse. Previous work from this laboratory demonstrated that the response-contingent presentation of drug-related, visual cues was at least as important as nicotine in the maintenance, extinction and reacquisition of self-administration in experienced rats. OBJECTIVES: In the present research, we asked whether these same visual cues are effective in promoting the acquisition of operant responding in drug naive rats. METHODS: Male Sprague-Dawley rats were tested for self-administration of IV nicotine (0.03 mg/kg, free base) in 1-h daily sessions when infusions were or were not paired with two lighting events: a 1-s cue light, followed by a 1-min period during which the chamber light was turned off and responding was not reinforced. RESULTS: Rats tested with cues plus nicotine rapidly acquired self-administration and increased their lever pressing rates as the schedule progressed from FR1 to FR5. Without cues, the rate of nicotine self-administration was low and no adjustments were made in response to increasing schedule demands. While one of the stimuli, turning off the chamber light, was shown to have primary reinforcing properties, its association with nicotine produced a synergistic enhancement of lever pressing. Acquisition of operant responding was also enhanced, but to a lesser extent, by a previously neutral compound stimulus, i.e. the nicotine-paired cue light presented with a 1-s tone. CONCLUSIONS: These results illustrate a powerful interaction between environmental stimuli and nicotine in the acquisition of operant responding and indicate that both intrinsically reinforcing and previously neutral cues can participate in this effect.  相似文献   
8.
Antioxidant flavan-3-ols and flavonol glycosides from Maytenus aquifolium   总被引:1,自引:0,他引:1  
TLC autographic assay revealed, in the EtOAc extract obtained from leaves and root bark of Maytenus aquifolium (Celastraceae), the presence of fi ve compounds exhibiting antioxidant properties towards beta-carotene. They were isolated and identified as epigallocatechin (1), (+) ouratea-catechin (2), proanthocyanidin (3), kaempferol 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (4) and quercetin 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (5). The isolates were investigated for their redox properties using cyclic voltammetry and for their radical scavenging abilities through spectrophotometric assay on the reduction of 2,2-diphenyl-pycryl hydrazyl (DPPH). These results were correlated to the inhibition of beta-carotene bleaching on TLC autographic assay and to structural features of the flavonoids.  相似文献   
9.
Rationale Current conceptualizations of drug reinforcement assume that drug-taking behavior is a consequence of the contingent, temporal relationship between the behavior and drug reward. However, stimulant drugs also potentiate the rewarding effects of other reinforcers when administered noncontingently. Objectives These studies were designed to determine whether noncontingent nicotine enhances the reinforcing properties of a nonpharmacological reinforcer and whether this direct effect facilitates operant behavior within the context of a nicotine self-administration procedure. Methods Rats self-administered nicotine or food, or received noncontingent nicotine, saline, or food either with or without a response-contingent, unconditioned reinforcing visual stimulus (VS). Results Noncontingent nicotine, whether delivered as discrete injections based on a pattern of self-administered nicotine or as a continuous infusion, increased response rates maintained by the VS. There were no significant differences in responding by animals that received contingent compared with noncontingent nicotine when a VS was available. This increase was not observed in the absence of the VS or as a consequence of noncontingent food delivery. Operant behavior was equally attenuated and reinstated by the removal and subsequent replacement of contingent and noncontingent nicotine. Nicotine supported self-administration in the absence of response-contingent, nicotine-paired stimuli; however, response rates were drastically reduced compared with nicotine self-administration with the VS. Conclusions Nicotine influences operant behavior in two ways: by acting as a primary reinforcer when it is contingent upon behavior, and by directly potentiating the reinforcing properties of other stimuli through a nonassociative mechanism. Nicotine self-administration and smoking may be largely dependent upon this later action. This work was supported by National Institute on Drug Abuse research grants, DA-10464 and DA-12655. "Principles of laboratory animal care" (NIH No. 85-23, revised 1985) were followed throughout all experiments. This research was approved by the University of Pittsburgh Institutional Animal Care and Use Committee, Assurance Number A3187-01  相似文献   
10.
Though socio‐economic status (SES) partially explains the experience of stress and health outcomes, most research to date has relied on a small number of traditional indicators that fail to capture the full domain of socioeconomic factors. The recent reconceptualization of perceived scarcity is proposed as a subjective indicator of SES when attempting to predict both stress and health outcomes. Although a conceptualization of perceived scarcity has been advanced, a psychometrically sound scale is needed to assess the utility and scientific import of this concept. No such scale exists. Therefore, the current paper describes the development, psychometric properties, and initial validation of the Perceived Scarcity Scale (PScS). Four studies using traditional scale development processes were employed to develop (Studies 1 and 2) and provide an initial validation (Studies 3 and 4) for the PScS. Results support the existing model of perceived scarcity and indicate that the measure is valid. Moreover, the scale predicted concurrent perceived stress, as well as longitudinal ratings of perceived stress, global health, quality of life, and symptoms of depression and anxiety. The development of the new scale provides clinicians and researchers with a brief, validated measure that can assess the level of perceived scarcity individuals currently experience.  相似文献   
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