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BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
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This study was to determine the dental caries prevalence among the Myanmar population, and to investigate the correlations between oral clinical indices and knowledge, attitudes and practices (KAP) on oral health. Subjects were randomly selected from 140,000 people residing in the Kyauktan township in a cross-sectional community-based study. The present analysis was confined to 739 subjects (353 males and 386 females) aged 12, 35-44 and 65-74 years, who were divided into two specified groups based on urban or rural location. KAP on oral health data and social demographic information were collected, while dental caries status was assessed by DMFT. The mean number of decayed teeth (DT) in rural areas was higher than that in urban areas, while the mean number of filled teeth (FT) in rural areas was lower than that in urban areas. Mean knowledge and attitude scores for correct answers were also significantly higher for the urban than the rural subjects. There were statistically significant correlations between the correct/incorrect responses to knowledge and attitude questionnaires on oral health and the mean number of DMFT. KAP pertaining to oral health of Myanmar population, especially those of rural subjects, might not be satisfactory and related to threaten their dental caries status.  相似文献   
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BACKGROUND: We aimed to examine the effect of smoking on outcomes following coronary artery bypass grafting (CABG). METHODS: We retrospectively analysed 6 367 consecutive patients who underwent CABG between April 1997 and March 2003. Logistic regression was used to risk adjust in-hospital outcomes, while Cox proportional hazards analysis was used to risk adjust Kaplan-Meier survival curves. Outcomes were adjusted for variables suggested by the American Heart Association and American College of Cardiology. RESULTS: 947 (14.9 %) patients were current smokers (smoking within 1 month of surgery), while 3857 (60.6 %) were ex-smokers and 1 563 (24.5 %) were non-smokers. After adjusting for differences in case-mix, current smokers were more likely to develop chest infections ( p < 0.001), atelectasis ( p < 0.001), and require ventilation longer than 48 hours ( p = 0.003). Current smokers were also more likely to stay in intensive care for more than 3 days ( p < 0.001). Ex-smokers were not associated with excess mortality ( p = 0.11), while current smokers had significantly increased mortality during follow-up ( p = 0.029). CONCLUSIONS: Patients should be encouraged to stop smoking to maximise the long-term benefits of CABG.  相似文献   
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3,3′-Diindolylmethane (DIM) has been investigated as a potential anti-cancer chemopreventive agent in many preclinical and clinical studies. In this study, we sought to characterize the pharmacokinetics of DIM and to build a pharmacokinetic (PK) and pharmacodynamic (PD) model of the DIM-induced gene expression of phase II drug metabolizing enzymes (DME), which potentially links DIM’s molecular effects to its in vivo chemopreventive efficacy. DIM (10 mg/kg) was administered intravenously (i.v.) to male Sprague–Dawley rats and blood samples were collected at selected time points for 48 h. The plasma concentration of DIM was determined using a validated HPLC method. The mRNA expression of NQO1, GSTP1 and UGT1A1 in blood lymphocytes was measured using quantitative PCR. An indirect response model was employed to relate the concentration of DIM to the expression of the genes NQO1, GSTP1 and UGT1A1, which were chosen as PD markers for DIM. After i.v. administration, the plasma concentration of DIM declined quickly, and the expression of target genes increased significantly, peaking at 1–2 h and then returning to basal levels after 24 h. The parameters in the PK–PD model were estimated. The PK–PD model aptly described the time delay and magnitude of gene expression induced by DIM. Our results indicate that DIM is effective at inducing various phase II DME, which are capable of detoxify carcinogens. This PK–PD modeling approach provides a framework for evaluating the acute effects of DIM or other similar drugs in clinical trials.  相似文献   
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We have previously shown that HIV-1 env subtypes B' (a Thai-B cluster within subtype B) and E (CRF01_AE) are distributed in Yangon, the capital city of Myanmar. However, HIV strains from the rest of country have not yet been genetically characterized. In the present study, we determined env (C2/V3) and gag (p17) subtypes of 25 specimens from central Myanmar (Mandalay). Phylogenetic analyses identified 5 subtype C (20%), in addition to 10 CRF01_AE (40%) and 4 subtype B' (16%). Interestingly, the remaining six specimens (24%) showed discordance between gag and env subtypes; three gag subtype B'/env subtype C, one gag subtype B'/env subtype E, one gag subtype C/env subtype B', and one gag subtype C/env subtype E. These discordant specimens were found frequently among injecting drug users (4 of 12, 33%) and female commercial sex workers (2 of 8, 25%) engaging in high-risk behaviors. The recombinant nature of these HIV-1 strains was verified in three specimens, indicating the presence of new forms of HIV-1 intersubtype C/B' and C/B'/E recombinants with different recombination breakpoints. The data suggest that multiple subtypes of B', C, and CRF01_AE are cocirculating in central Myanmar, leading to the evolution of new forms of intersubtype recombinants among the risk populations exhibiting one of the highest HIV infection rates in the region.  相似文献   
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A study was conducted in the Infectious Diseases Hospital, Yangon, for one year from August 1996 to 1997, to assess the extent and the factors related to HIV transmission among sexual partners of HIV/AIDS cases. It was a cross-sectional comparative study on 67 (61 males, 6 females) HIV positive individuals with or without AIDS, and their sexual partners. Separate interviews of index cases and partners were done, and clinical examination and laboratory tests for HIV and sexually transmitted diseases (STDs) were performed. HIV transmission was found in 41.8% of the partners. Male-to-female transmission was 39.3% (n=61) and female to male transmission was 66.7% (n=6), Seven and one half percent of the partners were suffering from AIDS. There were 4 (6.6%) pregnant mothers and 1 (25%) was HIV positive. Though 75% of the partners did not use condoms during their married life, HIV transmission was significantly reduced in the condom users (odds ratio (OR) = 0.18, 95% confidence interval (CI) 0.02-0.98 p = < 0.05). The seropositive men who were less than 30 years of age had greater HIV transmission (OR = 5.67, 95% CI 1.13-36.46). However, socio-demographic factors, number of marital partners and age of first sex partners, duration of marriage, number of sexual relationships between these couples, duration of HIV positivity and AIDS infection, immunological status of the index group and STD positivity among partners had no significant association with the transmission of HIV. This study demonstrated that the transmission of HIV was high among the sexual partners of persons with HIV infection. It also highlighted the requirement of effective counseling and preventive measures against HIV infection among the couples.  相似文献   
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