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1.
Lately, experts have turned to historical evidence to uncover the default mode of our sleep pattern. Even though there are some notable exceptions, most historians use a qualitative methodology based on scattered evidence in diaries, letters, novels, medical treatise and other literary sources. To provide fresh perspective in the debate, the present article develops a more quantitative approach. Drawing fresh evidence from early modern criminal records – viz the eyewitness reports of the Hoge Vierschaer or the local criminal court in Antwerp – we are able to debunk some classic stereotypes about premodern sleep patterns. Data reveal that most 18th‐century Antwerpers slept fewer hours than we would expect, slumbered in a monophasic way and rarely if ever took a nap during the day. Moreover, the start and end of sleep were less attuned to the solar cycle than we would imagine. Last but not least, the pattern also shows some fascinating weekly and seasonal variations.  相似文献   
2.
Purpose: A statistical assessment of a disease is often necessary before resources can be allocated to any control programme. No literature on seasonal trends of gonorrhoea is available from India. Objectives: The objectives were (1) to determine, if any, seasonal trends were present in India (2) to describe factors contributing to seasonality of gonorrhoea (3) to formulate approaches for gonorrhoea control at the national level. Materials and Methods: Seasonal indices for gonorrhoea were calculated quarterly in terms of a seasonal index between 2005 and 2010. Ratio-to-moving average method was used to determine the seasonal variation. The original data values in the time-series were expressed as percentages of moving averages. Results were also analyzed by second statistical method i.e. seasonal subseries plot. Results: The seasonally adjusted average for culture-positive gonorrhoea cases was highest in the second quarter (128.61%) followed by third quarter (108.48%) while a trough was observed in the first (96.05%) and last quarter (64.85%). The second quarter peak was representative of summer vacations in schools and colleges. Moreover, April is the harvesting month followed by celebrations and social gatherings. Both these factors are associated with increased sexual activity and partner change. A trough in first and last quarter was indicative of festival season and winter leading to less patients reporting to the hospital. Conclusion: The findings highlight the immediate need to strengthen sexual health education among young people in schools and colleges and education on risk-reduction practices especially at crucial points in the calendar year for effective gonorrhoea control.  相似文献   
3.
4.
Purpose: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface.

Materials and methods: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA).

Results: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts.

Conclusions: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface.  相似文献   

5.
Objective: Tea (Camellia sinensis Linn.; family: Theaceae) is popular as a stimulant beverage across the globe and is also utilized as a functional antioxidant in alternative medicine. This study has evaluated the impact of seasonal variation on phyto-constituents of tea.

Method: The antiproliferative potential of methanolic extracts of tea leaves collected in the rainy season (MECR) was compared with the extract of tea leaves collected in the autumn season (MECA) of the same mother plant. Evaluation of in vivo antitumor activity was carried out in adult female Swiss albino mice groups inoculated with Ehrlich ascites carcinoma (EAC) cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to compare efficacy of MECR with that of MECA in the EAC cell line. Both qualitative and quantitative tests for phytochemical constituents present in MECA and MECR were performed. Antitumor efficacy of both the extracts was determined by evaluating different tumor markers showing dose-dependent cytotoxicity.

Results: Statistically significant reduction in EAC-induced tumor was observed in MECR treated mice compared to MECA treated ones. Cell decimation was significantly higher with MECR treatment, where restoration of different parameters including tissue structures returned to normal. Moreover, gas chromatography–mass spectrometry (GC-MS) study revealed the presence of cyclobarbital and benzazulene derivative in MECR, which is thought to be a novel source of these chemicals.

Conclusions: To our knowledge, there is no report that has attempted to reveal nutritional changes in terms of efficacy and variation in anticancer constituents in tea leaves, plucked in two seasons. This study revealed a novel source of barbital and benzazulene derivative. The unique presence of cyclobarbital and benzazulene, as revealed from GC-MS data, in methanolic extract of tea leaves collected during the rainy season (MECR) may have contributed to its enhanced in vitro (adopting MTT assay) and in vivo (on EAC-infected Swiss albino mice) cytotoxicity vis-à-vis antiproliferative properties compared to methanolic extract of tea leaves collected during the autumn season (MECA). The nature of plucking leaves in the two selected seasons is different.  相似文献   

6.
Introduction: A seasonal affective disorder (SAD) is a subtype of unipolar and bipolar major depressive disorders. It is characterized by its annual recurrence of depressive episodes at a particular season, mostly seen in winter and is responsible for 10–20% of the prevalence of major depressive disorders. Some pathophysiological hypotheses, such as the phase delay and the monoamine depletion hypotheses, have been postulated but the exact cause has not been fully unraveled yet. Studies on treatment for SAD in the last decade are lacking. To tackle this chronic disease, attention needs to be drawn to the gaps in this research field.

Areas covered: In this systematic review, the authors give a broad overview of the pharmacological therapy available for SAD. Also, nutritional substances fitting well with the postulated hypotheses are reviewed for the treatment and prevention of SAD. There is a specific focus on the quality of the currently performed studies.

Expert opinion: Light therapy and fluoxetine are the only proven and effective acute treatment options for SAD, while bupropion is the only registered drug for prevention of SAD. This area of research is in dire need of valid large-scale and sufficiently reproducible randomized control trials.  相似文献   

7.
目的 掌握西安市鼠种构成、鼠密度及季节消长趋势等情况,为制定防鼠灭鼠措施提供科学依据。方法 2015—2019年按照西安市地理方位东、南、西、北共选择4个区(县),每个区(县)选择城镇居民区、农村自然村和食品餐饮业共5个监测点,奇数月中旬采用夹夜法监测,以生花生米为诱饵,晚放晨收。鉴定鼠种并计算鼠密度,采用χ2检验对5年间鼠类种群构成和不同生境鼠类种群构成进行统计学分析。结果 共捕获4类鼠495只,平均鼠密度为0.39%,2016年鼠密度最低,为0.27%,2018年鼠密度最高,为0.58%。鼠密度季节消长呈不明显的双峰型,小高峰和大高峰分别出现在1月和7月,鼠密度分别为0.44%和0.46%,11月鼠密度最低,为0.32%。农村自然村鼠密度最高,为0.84%,城镇居民区鼠密度最低,为0.23%。不同生境小家鼠(M. musculus)的构成比最高,鼠种构成差异有统计学意义(P<0.001)。城镇居民区鼠密度季节消长变化趋势平稳,农村自然村呈双峰趋势,食品餐饮行业呈单峰趋势。小家鼠(M. musculus)在不同鼠种中季节消长趋势明显,1月、7月和9月为高峰期。结论 2015—2019年西安市鼠密度呈现先上升后下降的趋势;不同年份、不同生境、不同鼠种鼠密度有差异。建议以农村为工作重心制定不同生境的防鼠灭鼠措施,以达到减少鼠类传染病的目的。  相似文献   
8.
Objectives. Low serum BDNF levels have been found in depressed patients. No study has systematically investigated whether individual symptoms or symptom profiles within a depressed population contribute to low BDNF levels found in depressed subjects. Methods. All 1070 patients with a past 6-month diagnosis of major depressive disorder from the Netherlands Study of Depression and Anxiety (NESDA) were included. Composite International Diagnostic Interview (CIDI) and Inventory of Depressive Symptoms (IDS) items were tested individually in separate multiple regression analyses with serum BDNF level as the dependent and the CIDI or IDS item as independent variable. Subsequently, we compared BDNF levels between patients with seasonal affective disorder (based on the Seasonal Pattern Assessment Questionnaire) and melancholic depression, atypical depression and moderate depression (based on a latent class analysis). All analyses were adjusted for confounders. Results. Only one item was significantly associated with serum BDNF levels, namely the CIDI item “loss of interest” (β = 0.14; P < 0.01). Counterintuitively the presence of this symptom was associated with higher BDNF levels. Other items and the comparison between different types of depression did not reveal significant differences. Conclusions. Decreased serum BDNF levels in depression cannot be attributed to a specific symptom or symptom cluster.  相似文献   
9.
单郑鹏 《光明中医》2021,(1):106-107
目的系统性评价子午流注针法联合中药外敷治疗腰椎间盘突出症患者的临床疗效。方法选取2019年1月—2020年1月接受治疗的非手术腰椎间盘突出症患者60例,采用信封法随机分为对照组和试验组30例,对照组采用常规针刺治疗,试验组在对照组的基础上应用子午流注针法联合中药外敷,观察2组患者治疗前后的M-JOA评分,评价治疗有效率。结果治疗后试验组腰痛评分(11.1±5.01)分,对照组为(15.9±5.85)分;试验组总有效率为96.7%,对照组为66.7%。治疗后试验组的腰痛积分和治疗总有效率比较,差异具有统计学意义(P<0.05)。结论子午流注针法治疗腰椎间盘突出症患者可有效改善临床症状,提高治疗效果,值得推广。  相似文献   
10.
The aim of this study was to define features of Guillain‐Barré syndrome in a large cohort of patients from three Western Balkans countries. Data from adult Guillain‐Barré syndrome (GBS) cases from 2009 to 2013 were retrospectively obtained from all tertiary health care centers. During the 5‐year period, 327 new cases of GBS were identified with a male to female ratio of 1.7 : 1. The most common GBS variants were demyelinating (65%) and axonal (12%). At nadir 45% of patients were chair‐bound, confined to bed, or required assisted ventilation, while 5% died. The crude incidence of GBS in Serbia and Montenegro was 0.93 per 100,000 population, and age‐adjusted incidence according to the world standard population was 0.86 per 100,000. Incidence was particularly high in 50‐ to 80‐year‐old men. Statistically significant seasonal variations of GBS were not observed. This study of patients with GBS in the Western Balkans allows us to prepare the health system better and to improve the management of patients. This study also opens opportunities for international collaboration and for taking part in the multinational studies on GBS.  相似文献   
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