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101.
AIMS: To estimate the magnitude and causes of blindness in people aged > or =50 years in Satkhira district, Bangladesh, and to assess the availability of cataract surgical services. METHODS: 106 clusters of 50 people aged > or =50 years were selected by probability-proportionate to size sampling. Households were selected by compact segment sampling. Eligible participants had their visual acuity measured. Those with visual acuity <6/18 were examined by an ophthalmologist. A needs assessment of surgical services was conducted by interviewing service providers. RESULTS: 4868 people were examined (response rate 91.9%). The prevalence of bilateral blindness was 2.9% (95% confidence interval (CI) 2.4% to 3.5%), that of severe visual impairment was 1.6% (95% CI 1.2% to 2.0%) and that of visual impairment was 8.4% (95% CI 7.5% to 9.3%). 79% of bilateral blindness was due to cataract. The cataract surgical coverage was moderate; 61% of people with bilateral cataract blindness (visual acuity <3/60) had undergone surgery. 20% of the 213 eyes that had undergone cataract surgery had a best-corrected poor outcome (visual acuity <6/60). The cataract surgical rate (CSR) in Satkhira was 547 cataract surgeries per million people per year. CONCLUSIONS: Although the prevalence of blindness and visual impairment was lower than expected, the CSR is inadequate to meet the existing need, and the quality of surgery needs to be improved.  相似文献   
102.
上海26万妇女乳房自我检查随机试验   总被引:9,自引:2,他引:9  
目的论证指导妇女进行乳房自我检查(BSE)是否能有效降低乳腺癌患者的死亡率。方法自1989年10月起,上海26.6万名年龄在30~64岁的妇女,随机进入指导组(132979名)和对照组(133085名)。在指导组,最初先由医务人员做规范的BSE手法演示,随后的4年中,使用BSE录像带进行二次强化教育,并定期进行BSE指导和在医务人员监察下进行BSE操作。本研究进行5年,全部活动均被记录。队列人群随访到2000年7月,乳腺癌患者的生存状况随访到2001年12月。统计分析采用Kaplan-Meier方法、Logrank检验以及Cox模型。结果指导组检出乳腺癌864例,其中死于乳腺癌133例;对照组检出乳腺癌896例,其中死于乳腺癌130例。两组乳腺癌病例的肿块大小、TNM分期和累积死亡率的差异均无统计学意义(P均>0.05)。但是指导组比对照组有较多和较小的纤维腺瘤被检出(P<0.01)。结论对人群开展BSE教育和指导,未能降低人群的乳腺癌死亡率;接受BSE教育的妇女比没有接受教育的妇女可检出较多的和较小的良性乳房肿块。  相似文献   
103.
From 1998 to 1991, an in-person baseline interview was administered to approximately 267,400 female textile workers in Shanghai, China. The cohort was followed until July 2000 for incident cancer cases. Incidence rate ratios (RR) for 12 types of cancers in users of oral contraceptives (OCs) were calculated using Cox Proportional Hazards analysis. There was a reduced risk of uterine corpus cancer for women who had ever used OCs (RR = 0.68, 95% CI = 0.45–1.04) and a trend of decreasing risk with increasing duration of use (p = 0.015). There was an increased risk of colon cancer in women who had used OCs for 10 years or more (RR = 1.56, 95% CI = 1.01–2.40) and an increased risk of rectal cancer in women who had ever used OCs (RR = 1.31, 95% CI = 0.98–1.75), with a trend of increasing risk with increasing duration of use (p = 0.017), but these associations may have been due to uncontrolled confounding by physical activity or other non-causal factors. No associations were observed between OCs and the risk of all cancers combined or for any of the nine other cancers. It is unlikely that the use of OCs has contributed to the temporal trends in cancer incidence in China in recent decades.  相似文献   
104.
A pilot study tested the feasibility of conducting occupational health research in Bangladesh while examining prevalence of asbestos-related diseases including asbestosis, work-related respiratory symptoms, and attitudes to occupational health and safety among a group of internal migrant ship breakers. Data was collected on clinical and work history, respiratory symptoms, and occupational health and safety practices in Bengali. A B-reader read all postero-anterior chest x-rays. In the 104 male ship breakers studied, prevalence of asbestos-related disease was 12%, of which asbestosis accounted for 6%. Knowledge of asbestos and occupational health and safety measures were almost nonexistent. The prevalence of asbestos-related diseases is low compared to studies in shipbuilders and repairers, but a risk underestimate could have resulted from challenges identified during study design and implementation including: industry noncooperation and a culture of corruption; technological and language barriers; and a regional lack of physician knowledge and research on occupational diseases.  相似文献   
105.
Background: The Faculty of Medicine at the American University of Beirut implemented a new medical curriculum, which included 90 team-based learning (TBL) sessions in years 1 and 2 of medical school.

Methods: A validated team performance scale (TPS) and peer evaluation of communication skills, professionalism and personal development were collected at different time points during the two years. Grades on the individual and group readiness assurance tests and an evaluation form were collected after every TBL session.

Results: Students generally positively evaluated most TBL sessions as promoters of critical thinking and appreciated the self-learning experience, though they preferred and had better individual grades on those that entailed preparation of didactic lectures. There was a sustained and cumulative improvement in teamwork skills over time. Similar improvement was noted with peer evaluations of communication skills, professionalism, and personal development over time.

Conclusions: This is the first report about such a longitudinal follow-up of medical students who were exposed to a large number of TBL sessions over two years. The results support the suggestion that TBL improves medical students’ team dynamics and their perceived self-learning, problem solving and communication skills, as well as their professionalism and personal development.  相似文献   
106.
Persistent infection with Helicobacter pylori confers an increased risk of peptic ulceration and gastric adenocarcinoma. Reactive oxygen and nitrogen species play a crucial role in the progression from normal gastric mucosa to cancer. The aim of the present study was to investigate the plasma malondialdehyde and nitric oxide levels in H. pylori related gastroduodenal diseases and associate their levels with gastric pathology and genotypes of H. pylori. Malondialdehyde and nitric oxide levels in plasma samples of 250 subjects were spectrophotometrically determined. Subsequently, genotypic and histopathological assessment was performed in gastric biopsies obtained during endoscopy. The levels of MDA and NO exceeded in subjects infected with genotype-1 of Hp than those with other genotypes suggesting more precise interaction of highly virulent strains of Hp in eliciting severe tissue damage. In conclusion, the study demonstrates close relationship between the plasma malondialdehyde and nitric oxide levels, gastric histopathology and genotypes of H. pylori.  相似文献   
107.
108.

Aims

Recent evidence suggests that intake of excessive dietary fat, particularly saturated fat and trans-hydrogenated oils (trans-fatty acids: TFA) can impair learning and memory. Central obesity, which can be induced by neonatal injections of monosodium Glutamate (MSG), also impairs learning and memory. To further clarify the effects of dietary fat and MSG, we treated C57BL/6 J mice with either a TFA-enriched diet, dietary MSG, or a combination of both and examined serum lipid profile and spatial memory compared to mice fed standard chow. Spatial learning was assessed at 6, 16 and 32 weeks of age in a Morris Water Maze (MWM). The subjects were given four days of training to find a hidden platform and a fifth day of reversal learning, in which the platform was moved to a new location.

Results

The TFA + MSG combination caused a central adiposity that was accompanied by impairment in locating the hidden platform in the MWM. Females in the TFA + MSG group showed a greater impairment compared to the other diet groups, and also showed elevated levels of fasting serum LDL-C and T-CHOL:HDL-C ratio, together with the lowest levels of HDL-C. Similarly, males in the TFA + MSG diet group were less successful than control mice at locating the hidden platform and had the highest level of abdominal adiposity and elevated levels of fasting serum LDL-C.

Conclusion

Dietary trans-fat combined with MSG increased central adiposity, promoted dyslipidemia and impaired spatial learning.  相似文献   
109.
For white light-emitting diode (LED) applications, semiconductor quantum dots (QDs) have been widely utilized as efficient down-converters to change the blue color of the light source into different emission colors. Because QDs offer spectral tunability over the entire visible light range, as well as improved color purity, they have rapidly replaced conventional phosphor-based white LEDs. However, for the sustainable growth of QD-mediated LEDs, the amount of QDs required must be reduced by enhancing the color-conversion efficiency. For this purpose, we prepared poly(lauryl methacrylate) (PLMA) composite films by the photo-crosslinking polymerization of lauryl methacrylate monomers in the presence of Au@Ag@SiO2 nanoparticles (NPs) and InP@ZnS QDs. In the PLMA composites, the Au@Ag NPs not only amplified the blue light source but also modified the relaxation of the excited QDs via localized surface plasmon resonance. This resulted in a maximum 12.9-fold enhancement in the QD fluorescence. Because the blue light source in this study can be easily replaced by blue LEDs, the enhanced efficiency of QD emissions via the plasmonic effect could potentially increase the performance of QDs for display applications.

Poly(lauryl methacrylate) films containing Au@Ag@SiO2 nanoparticles and InP@ZnS quantum dots were prepared to investigate metal-enhanced fluorescence in polymer composites.  相似文献   
110.
ObjectiveTo evaluate the immunomodulatory role of vitamin D3 in prevention of pregnancy loss in cases of recurrent miscarriage.Patients and methodsA total of 40 pregnant women with gestational age at or less than 6 weeks with recurrent miscarriage were enrolled in the present study and randomly assigned to study and control group each (n = 20 for each group) after fulfilling certain inclusion and exclusion criteria. All participants were assessed through complete history, general and obstetric history, ultrasound assessment and routine full laboratory evaluation. IFN-γ was assessed at ?6 week gestation on recruitment, then after treatment every 2 weeks till 14th week for both groups. Both groups received standard measures for cases with recurrent miscarriage. Study group participants were treated with oral vitamin D3 supplementation. Outcome measures included continuing pregnancy rate and change in INF-γ values between first and final assays.ResultsNo statistically significant difference was noted between both groups regarding baseline demographic, clinical characteristics and ultrasonographic findings. Control group participants were found to have significantly higher levels of IFN-γ compared to the study group after treatment. Risk of miscarriage was 15% lower among the study group than the control group. Continuing pregnancy rate was 70% in the study group and 55% in the control group. No significant difference was found between both groups regarding symptoms suggesting vitamin D3 side effects.ConclusionAlthough statistically insignificant, vitamin D3 oral supplementation has resulted in reducing risk of pregnancy loss up to 15% among women with recurrent miscarriage so it is a matter that is worth more attention and large scale studies with larger sample size may result in more significant results.  相似文献   
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