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21.
Background:  T helper (Th)-17 cells are a subset of T helper lymphocytes that exert regulatory activities. Recently, it has been reported that serum interleukin (IL)-17 levels are high in the most severe cases of birch allergy studied outside the pollen season.
Objective:  The aim of this study was to investigate a possible relationship between serum IL-17 levels and clinical parameters in patients with allergic rhinitis studied during the pollen season.
Methods:  In all, 56 patients with persistent pollen-induced allergic rhinitis were evaluated during the pollen season. Serum IL-17 levels were evaluated by enzyme-linked immunosorbent assay. Symptoms were assessed by visual analogue scale, drug use was monitored and peripheral eosinophils were counted.
Results:  Serum IL-17 levels were significantly related to clinical symptoms, drug use and peripheral eosinophil counts ( P  = 0.0001 for all).
Conclusion:  This study provides evidence that serum IL-17 level assessment might be considered to classify allergy severity.  相似文献   
22.
不同树龄银杏叶在不同季节中总黄酮和总内酯的含量变化   总被引:16,自引:1,他引:15  
目的:确定银杏叶最适宜采收季节。方法:采用HPLC法(二级管阵列检测器DAD和蒸发光散射检测器ELSD)分别测定银杏叶中总黄酮和总内酯的含量。结果:不同树龄,不同季节的银杏叶总黄酮、总内酯含量不同,结论:银杏叶的总黄酮、总内酯以二、三年生的为高,总黄酮在5月份,总内酯在9月份含量为高。  相似文献   
23.
目的研究1997年8月~2003年5月六安市21例流行性出血热病例,探讨流行性出血热的流行规律,为流行性出血热防治提供依据。方法对流行性出血热病人个案调查表中的发病季节、年龄、性别、传播途径和职业特点等进行分析。结果本地区流行性出血热在春夏间和秋冬间均有发病,分别占发病人数的61.9%和38.1%。年龄以30~49岁所占比例最大,为85.7%。涉及的人群主要是男性青壮年农民,也有极少数为经商和机关工作人员。结论家鼠型和野鼠型出血热在本地区均有病例发生,病例以青壮年男性为主,接触传播为流行性出血热的主要传播途径。  相似文献   
24.
目的了解老年人群血浆维生素K和维生素D水平的季节变化。方法对85名健康老年人用放射免疫分析法测定春秋两季血浆维生素D(25(OH)D)和甲状旁腺素(PTH)含量,用高压液相色谱法测定血浆维生素K含量。结果血浆维生素K水平女性在春秋两季均明显高于男性,而男性和女性各自无季节性差异。无论男女秋季血浆维生素(25(OH)D)水平明显高于春季,同一季节内男女间差异无统计学意义。维生素D缺乏率女性春季为63.4%,秋季为7.3%。男性春季为65.9%,秋季无缺乏者。春季维生素D缺乏率显著高于秋季(P<0.05)。男女秋季血浆PTH浓度明显低于春季。老年女性春季血浆25(OH)D浓度和血浆PTH浓度之间呈负相关(r=-0.426,P<0.001)。结论该人群血浆25(OH)D和PTH有明显的季节变化,春季血浆25(OH)D水平低。而血浆维生素K没有季节变化。  相似文献   
25.
Aim: To evaluate the characteristics of semen produced by one- and two-years old White Italian ganders duringentire reproductive season, in order to clarify whether the young ganders are responsible for a low fertility rate in yougeese. Methods: Males were kept individually in cages under natural light. Semen was collected by dorso-abdonhal massage three times a week and routine examination was performed. Results: The mean ejaculate volume (2and 1.6 mL, respectively) and sperm concentration (323 and 281 × 10~6/mL, respectively) in one-year-old gandwere higher than those of two-year-old ones. The percentages viable spermatozoa of one- and two-year-old gandwere similar (91.4 and 92.3%, respectively), but the percentage of normally formed viable spermatozoa was signicantly higher in the older ganders than in the younger (47.8 and 42.9%, respectively, P < 0.05). Conclusion:The semina from one- or two-year-old Ganders were similar in regard to volume, sperm density and sperm motility,the percentage of norma  相似文献   
26.
The aim of this study was to explore whether the risk of sudden infant death syndrome (SIDS) associated with prone sleeping position and other risk factors varies with season. The study was a large nation-wide case-control study, which compared 485 cases with 1800 controls. Parents of 393 (81.0%) cases and 1591 (88.4%) controls were interviewed. Obstetric records were also examined. Infants dying in winter were older and had lower birthweights than those dying in summer. The increased risk of SIDS associated with prone sleeping position was greater in winter than in summer. In contrast, the increased risk of SIDS associated with excess thermal insulation and bed sharing was less in winter than in summer. Prone sleeping position accounts for about half of the difference between the mortality rate in summer and that in winter. This suggests that some factor related to season modifies the effect of prone sleeping position.  相似文献   
27.
BACKGROUND: Clinical management of tuberculosis in Russia involves lengthy hospitalizations, in contrast to the recommended strategy advocated by the World Health Organization. METHODS: We used Fourier transform, spectral analysis and Student's t-test to analyse periodic and seasonal variations in admission and discharge rates for tuberculosis hospitalizations in 1999-2002, using routinely captured data from the Samara Region, Russia. RESULTS: Hospital admissions in colder months were significantly higher than in warmer months. The mean monthly adjusted number of admissions in colder and warmer months for all adults was 413 and 372 (P < 0.01), for unemployed adults 218 and 198 (P < 0.02) and for pensioners 104 and 82 (P < 0.05). Hospital discharges varied seasonally. Maximum differences between admissions and discharges occurred in colder months and minimum differences were observed in warmer months. CONCLUSIONS: As hospitalizations of tuberculosis patients in colder months fulfil an important social need, shifts to ambulatory care must be carefully managed.  相似文献   
28.
BACKGROUND: Although seasonal variation of birth weight has been reported previously, contributing factors such as the meteorological factor and its specific period of exposure remain unclear. AIM: To investigate the effect of season on birth weight and to determine the meteorological factor and its specific period of exposure which can contribute to any seasonal variation in birth weight. METHODS: Retrospective analysis of 3333 singleton live births after 36 completed weeks of pregnancy. Maternal age, parity, route of delivery, sex and individual meteorological variables for the first, second, and third trimesters of each pregnancy were analysed using multiple regression analysis with the birth weight as the dependent variable. RESULTS: A seasonal pattern was observed with lowest birth weights in women who had their last menstrual periods in summer and autumn. Upon multiple regression analysis, sex, parity, mode of delivery, and the temperature which the mother was exposed to in the second trimester were the independent determinants of birth weight. CONCLUSION: Exposure to low outdoor ambient temperature in the midtrimester can be associated with low birth weight.  相似文献   
29.
Variation at nine microsatellite loci was investigated to understand how Anopheles arabiensis populations survive the dry season in the sahelian region of Senegal. Low estimates of genetic differentiation (F(ST) = 0.012, R(ST) = 0.009) between two populations, 250 km apart, suggested extensive gene flow across this distance. Despite extreme seasonal fluctuation in abundance with dry season minima in which mosquitoes virtually disappeared, allele frequencies remained stable over time in the village of Barkedji from August 1994 to December 1997 (including four rainy seasons and three dry seasons). The effective population size (Ne) was estimated to be 601 with 95% CI (281, 1592), providing strong evidence against annual bottlenecks. Differences in measures of genetic diversity and linkage disequilibrium between the dry and the rainy seasons were not detected. These results suggest that despite extreme minima in local density, An. arabiensis maintains large permanent deme spread out over large area.  相似文献   
30.
芍药不同部位和不同采收期6个化学活性成分含量的比较   总被引:4,自引:0,他引:4  
运用RP-HPLC法检测了赤芍不同采收期、不同生长年限和原植物不同部位的没食子酸、儿茶素、芍药内酯苷、芍药苷、苯甲酸和丹皮酚的含量。结果表明: 秋季采收的赤芍药材中儿茶素和芍药苷含量最高, 苯甲酸含量较低; 生长年限越长的赤芍儿茶素和芍药苷含量越高; 芍药根部的儿茶素和芍药苷含量最高, 鲜叶中也含有芍药苷。研究提示, 赤芍应以秋季采收成年植株为佳; 芍药苷在叶中已开始合成, 而儿茶素在叶中未检测到, 在根部占较大比例。  相似文献   
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