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71.
BACKGROUND: Human papillomavirus (HPV) infections cause disease in men and women, and male-to-female HPV transmission influences the risk of cancer in females. The purpose of the present study was to describe the overall and age-specific incidence and clearance of HPV infections in men. METHODS: In a prospective cohort study of 290 men aged 18-44 years, participants were examined at baseline and every 6 months, with a mean duration of follow-up of 15.5 months. RESULTS: The period prevalence was 52.8% for any, 31.7% for oncogenic, and 30.0% for nononcogenic HPV infection. The 12-month cumulative risk of acquiring a new HPV infection was 29.2%. Incidences of HPV types 6, 11, 16, and 18 were 2.8, 0.5, 4.8, and 0.8 per 1000 person-months, respectively. The median time to clearance of any HPV infection was 5.9 months (95% confidence interval, 5.7-6.1 months), with comparable times to clearance for oncogenic and nononcogenic infections. Approximately 75% of men tested negative for any HPV 12 months after initial HPV detection. Age was not significantly associated with HPV incidence or duration of infection in men. CONCLUSION: HPV infection in men was common, with relatively rapid rates of acquisition and clearance.  相似文献   
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Accurate knowledge about human sexual behaviors is important for increasing our understanding of human sexuality; however, there have been few studies assessing the reliability of sexual behavior questionnaires designed for community samples of adult men. A test–retest reliability study was conducted on a questionnaire completed by 334 men who had been recruited in Tucson, Arizona. Reliability coefficients and refusal rates were calculated for 39 non-sexual and sexual behavior questionnaire items. Predictors of unreliable reporting for lifetime number of female sexual partners were also assessed. Refusal rates were generally low, with slightly higher refusal rates for questions related to immigration, income, the frequency of sexual intercourse with women, lifetime number of female sexual partners, and the lifetime number of male anal sex partners. Kappa and intraclass correlation coefficients were substantial or almost perfect for all non-sexual and sexual behavior items. Reliability dropped somewhat, but was still substantial, for items that asked about household income and the men’s knowledge of their sexual partners’ health, including abnormal Pap tests and prior sexually transmitted diseases (STD). Age and lifetime number of female sexual partners were independent predictors of unreliable reporting while years of education was inversely associated with unreliable reporting. These findings among a community sample of adult men are consistent with other test–retest reliability studies with populations of women and adolescents.  相似文献   
74.
The fundamental aim of this study was to identify factors crucial for the development of effective cancer prevention programs for American Indian (AI) populations. Toward that end, we developed an instrument to assess the influence of traditionalism on health risks such as smoking, consumption, and obesity. A population-based survey was conducted among 559 randomly selected women living on the Hopi reservation aged 18 years and older, from July through December 1993. To construct a traditionalism score, we conducted focus groups in the community. A multidimensional approach was adopted by assessing three dimensions of native culture: language usage; cultural participation, or participation in such activities as Hopi ceremonies; and percentage of life spent off-reservation. A mean score of the three dimensions was computed for each respondent. High levels of traditionalism were significantly associated with disease protective behaviors, such as practicing traditional Hopi activities to keep healthy (OR = 3.07), and significantly inversely associated with disease risk factors such as smoking (OR = 0.26) and obesity (OR = 0.60) independent of age, marital status, and education. As these data provide a strong rationale for the promotion of traditions in public health programs aimed at decreasing rates of chronic disease among AI women, we conclude this paper with a discussion of the importance of traditionalism and how it might be accurately assessed.  相似文献   
75.
OBJECTIVES: Oral hairy leukoplakia (HL) is an acan-thotic, hyperparakeratotic lesion characterised by the presence of a replicative Epstein-Barr virus (EBV) infection in the superficial and adjoining layers of the epithelium. EBV or its gene products are capable of modifying epithelial differentiation. The aim of this study was to establish whether the presence of EBV was associated with an alteration in cell turnover by assessing bromodeoxyuridine (BrdU) incorporation and Ki 67 expression in lesional tissue and control mucosa.
METHODS: Biopsies of HL together with age, site and sex matched controls ( n = 7 and 8 respectively) were incubated in 200 μM BrdU in vitro , fixed in methacarn and processed to paraffin wax. Following acid hydrolysis, incorporated BrdU and Ki 67 were identified in serial 5 fim sections using a three-stage immunoperoxidase technique and cell density expressed as the number of positive cells per mm basement membrane length.
RESULTS: Overall, there was no difference in the number of BrdU positive cells per mm basement membrane length between control and HL tissue. However, within HL alone, the presence'of focal EBV replication was associated with a significant reduction in the number of basal cells incorporating BrdU compared to adjacent EBV free areas (P < 0.05). There was no significant difference between Ki 67 positive cells in control and HL tissue and no evidence of a reduction of Ki 67 positive cells in areas associated with EBV replication.
CONCLUSIONS: These results suggest that there is no evidence of a generalised alteration of the proliferative capacity of basal cells in HL, although the focal reduction in BrdU incorporation may reflect subtle changes on cell turnover by EBV infection.  相似文献   
76.
Lymphadenopathy is the commonest presentation in HIV positive individuals. Fine needle aspiration cytology of 196 HIV positive patients was studied during six monthly review. 75% paients in this study who were asymptomatic were detected to have lymphadenopathy during the surveillance. 82% had lymph nodes smaller than 1cm size. Lymphadenopathy at more than one site was observed in 46.8% cases. Commonest opportunistic infection noticed was tuberculosis (TB) in 34.2%. Cyto-morphologically reactive pattern with Add fast bacilli (AFB) positivity was observed in 16.4% of TB cases. In 2.9% cases AFB were detected even in the tissue fluid. Negative images of AFB were observed in the macrophages in 3 cases. TB was detected with equal frequency in both asymptomatic and symptomatic groups. Axillary nodes pose problem due to deeper location. False positives were a case of dermatopathic lymphadenopathy and a case of Kimura''s disease. False negatives include two cases of TB lymphadenitis. Pathogens should be looked for irrespective of cyto-morphology. Biopsy should be done to confirm cases of lymphomas. Fine needle aspiration cytology should be included in the protocol of six monthly review of HIV infected cases.KEY WORDS: AIDS, FNAC, HIV, Lymph node, Tuberculosis  相似文献   
77.

Background:

Current treatment strategies for head and neck cancer are associated with significant morbidity and up to 50% of patients relapse, highlighting the need for more specific and effective therapeutics. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) and Smac mimetics (SMs) are promising anticancer agents, but their effect on head and neck squamous cell carcinoma (HNSCC) remains unknown.

Methods:

We examined the response of a panel of nine HNSCC cell lines to TRAIL and SMs and investigated the mechanism of cell type-specific response by functional analysis.

Results:

Head and neck cancer cell lines revealed a converse response pattern with three cell lines being highly sensitive to Smac-164 (SM) but resistant to TRAIL, whereas the other six were sensitive to TRAIL but resistant to SM. Distinct protein expression and activation patterns were found to be associated with susceptibility of HNSCC cell lines to TRAIL and SM. Tumour necrosis factor-related apoptosis-inducing ligand sensitivity was associated with high caspase-8 and Bid protein levels, and TRAIL-sensitive cell lines were killed via the type II extrinsic apoptotic pathway. Smac mimetic-sensitive cells expressed low levels of caspase-8 and Bid but had high TNF-α expression. Smac mimetic-induced cell death was associated with caspase-10 activation, suggesting that in the absence of caspase-8, caspase-10 mediates response to SM. Cotreatment with TNF-α sensitised the resistant cells to SM, demonstrating a decisive role for TNF-α-driven feedback loop in SM sensitivity.

Conclusions:

Tumour necrosis factor-related apoptosis-inducing ligand and SMs effectively kill HNSCC cell lines and therefore represent potential targeted therapeutics for head and neck cancer. Distinct molecular mechanisms determine the sensitivity to each agent, with levels of TNF-α, caspase-8, Bid and caspase-10 providing important predictive biomarkers of response to these agents.  相似文献   
78.
At present it is unknown whether the higher prevalence of human papillomavirus (HPV) infection among smokers in men is attributed to a higher probability of acquiring an infection or because of longer infection persistence. Thus, we investigated the role of smoking on the incidence (acquisition) and clearance (persistence) of genital HPV infections among 4,026 men in the HPV in Men (HIM) Study, a multinational prospective study of the natural history of genital HPV infection in men. Genital HPV infections were grouped by any, oncogenic and nononcogenic HPV infections and smoking status was categorized as current, former and never smokers. The incidence of any, oncogenic and nononcogenic HPV infections was significantly higher among current smokers compared to former and never smokers (p < 0.01). In multivariable analyses adjusting for sexual behavior and potential confounders, when compared to never smokers, current smokers exhibited significantly higher probability of acquiring any [hazard ratio (HR) = 1.23; 95% confidence interval (CI) 1.02–1.50] and nononcogenic (HR = 1.21; 95% CI 1.00–1.45) infections and a borderline significant probability for oncogenic infections (HR = 1.18; 95% CI 0.98–1.41). Although the median duration of HPV infection was generally longer among current smokers, we found no statistically significant associations in the multivariable analyses. Overall, these results demonstrated that current smoking exhibited the highest incidence and highest probability of acquiring genital HPV infections.  相似文献   
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