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111.
阿魏酸钠对实验性兔肺气肿形成的抑制作用   总被引:1,自引:0,他引:1  
目的研究阿魏酸钠对实验性兔肺气肿形成的抑制作用。方法27 只健康雄性新西兰白兔随机均分为模型组(A组),阿魏酸钠干预组(B组)和对照组(C组)。A、B两组气管内一次性注入胰弹性蛋白酶,1周后B组腹腔注入阿魏酸钠干预,C组予生理盐水作为对照,于第14、28、42 天观察血气变化、光镜和电镜形态学改变及图文半定量分析。结果B组血气分析和半定量分析结果较A组明显改善(P<0 05),光镜、电镜形态学观察与对照组相近(P>0 05)。结论在胰蛋白酶所致实验性兔肺气肿病变的早期,阿魏酸钠可以阻抑肺气肿形成。  相似文献   
112.
Chronic obstructive lung disease(COPD), predominantly emphysema, causes several thoracic anatomical and hemodynamic changes which may cause changes in various electrocardiographic parameters. A 12-lead electrocardiogram(ECG), which is often a part of routine evaluation in most clinical settings, may serve as a useful screening modality for diagnosis of COPD or emphysema. Our current article aims to provide a comprehensive review of the electrocardiographic changes encountered in COPD/emphysema utilizing published PubMed and Medline literature database. Several important ECG changes are present in COPD/emphysema and may serve as a good diagnostic tool. Verticalization of Pvector, changes in QRS duration, pattern recognition of precordial R-wave progression and axial shifts can be considered some of the most valuable markers among other changes. In conclusion, 12-lead surface electrocardiogram can serve as a valuable tool for the diagnosis of COPD and/or emphysema. An appropriate knowledge of these ECG changes can not only help in the diagnosis but can also immensely help in an appropriate clinical management of these patients.  相似文献   
113.
肺气肿的心向量图诊断标准探讨   总被引:2,自引:0,他引:2  
为探索心向量图对肺气肿的诊断标准,观察51例经肺功能检查诊断为慢性阻塞性肺气肿和25例对照组的心向量图.结果发现两组横面左前、左后及X轴后方的QRS环密度积分等指标差异有非常显著意义(P<0.01).如在原来肺气肿心向量图诊断标准的基础上增加上述指标,可使肺气肿诊断阳性率从84%提高至96%,差异有显著意义(P<0.05).说明新标准敏感性较高,可作为心向量图诊断肺气肿参考依据.  相似文献   
114.
Cigarette smoke has been implicated in the pathogenesis of a variety of diseases that affect connective tissues. The effect of the gas phase of cigarette smoke on hyaluronic acid was investigated in vitro. The smoke markedly reduced the chain length of purified hyaluronic acid as assessed by both viscometry and gel chromatography. The hyaluronate exposed to smoke, nevertheless, could aggregate proteoglycans, although the viscosity of the aggregates was lower than in those formed with the unexposed material. The degradation of the hyaluronate was a rapid phenomenon and was inhibited by dimethylsulfoxide, a known scavenger of hydroxyl radicals. We conclude that free radicals in the gas phase of cigarette smoke degrade hyaluronic acid in vitro.  相似文献   
115.
复方营养液对肺气肿大鼠肺动脉高压及膈肌的影响   总被引:4,自引:0,他引:4  
经气管内滴注猪胰弹性蛋白酶,复制大鼠肺气肿模型。观察复方营养液(Ensure+硒酸酯多糖)对肺气肿大鼠肺动脉高压、右心/左心+室间膈比值及膈肌张力的影响。结果表明,复方营养液连续灌胃1个月可明显提高隔肌张力(P<0.01),降低肺动脉高压(P<0.05),减少右心/左心+室间膈比值(P<0.05).提示复方营养液为一有效的肺气肿康复治疗手段。  相似文献   
116.
Background: We compared our results with bullous vs diffuse emphysema by performing a bilateral thoracoscopic stapled volume reduction technique in 15 patients (age 45–80, 10 males, five females). Methods: Eight patients demonstrated bullous emphysema and seven patients diffuse emphysema. Lung reduction was performed with a bilateral thoracoscopic stapled technique utilizing bovine pericardium in the supine position. Results: Comparison of the bullous versus diffuse groups revealed no significant differences in means for the following variables: length of air leak (7.5 vs 3.3 days); length of stay (8.1 vs 6.5 days); pre-op FEV1 (23% vs 22%); pre-op dyspnea index (3.4 vs 3.6). At 3 months the bullous subset had a highly significant improvement (p < 0.007) in FEV1 (88%) compared with the diffuse subset FEV1 (59%). Conclusions: These early results suggest that patients with bullous emphysema are at no greater risk and demonstrate a significantly greater improvement in FEV1 than patients with diffuse emphysema. Received: 14 May 1997/Accepted: 6 August 1997  相似文献   
117.
Single-lung transplantation may induce asynchronous performance between the respiratory muscles of the chest. The objective of this study was to investigate the influence of a single transplanted lung on respiratory muscle mechanics. The force and power of the sternomastoid, external intercostal and external oblique muscles were evaluated throughout a range of respiratory maneuvers in emphysematic patients with a single transplanted lung and compared with that of healthy subjects. A significant differences was observed between the force, work and power of the muscles on the two sides of the chest in emphysematic patients (P<0.05). The control group demonstrated higher averaged maximal force, work and power. The total work done during either inspiration or expiration by the external intercostal and external oblique muscles on the side of the transplanted lung were higher compared with that of the native lung side and compared with the control group. The asynchrony between the lungs after single-lung transplant leads to asynchronous muscle force and work and lesser muscle strength compared to healthy subjects.  相似文献   
118.
We report a 4-month-old boy who developed scrotal emphysema following removal of a chest drain. The initial diagnosis was made by ultrasonography. This report describes the sonographic findings, pathophysiological mechanisms and outcome of this rare entity.  相似文献   
119.
Chronic pulmonary diseases are a major cause of morbidity and mortality worldwide. The present study is a case–control study nested in a defined cohort, undertaken in Athens, Greece, in order to investigate the association between long-term exposure to ambient air pollution and the development of chronic bronchitis, emphysema or chronic obstructive pulmonary disease (COPD). Individualized personal exposure assessment has been applied based on long-term residential and occupational subject history linked with geographical air pollution distribution. The first consecutive 3904 participants from the European Prospective Study into Cancer and Nutrition (EPIC), all residents of Athens, were asked to complete a questionnaire. One hundred and sixty-eight participants reporting a history of COPD symptomatology and 168 healthy controls recruited from the same study base individually matched for age and gender, were visited by a physician at their homes for conducting spirometry and a medical interview. Eighty-four of the 168 self-identified as cases were diagnosed as having chronic bronchitis, emphysema or COPD. Logistic regression models were used for statistical evaluation. Cases were more exposed to air pollution compared to controls. The estimated odds ratio (OR) indicates an increase of 37% in the risk of medically confirmed cases per exposure quartile (p = 0.02). When most of the subjects exposed are considered vs. all others, there is a twofold increase in disease risk (p = 0.03). Our findings provide evidence that long-term exposure to air pollution is an important factor in the development of chronic respiratory diseases.  相似文献   
120.
目的:评价肺气肿在HRCT双项扫描时的表现。方法:对临床和肺功能检查确诊的肺气肿病人40例与正常对照组20例,用HRCT分别进行深呼气末和深吸气末的CT扫描,测其CT值。所获数据用t检验。结果:肺气肿组在深吸气末的CT值与正常组相近,但在深呼吸末则明显低于正常组。其差异:正常组呼吸气之间平均为193Hu,肺气肿的差值为20.3Hu。结论:HRCT在诊断肺气肿时,呼气末要比吸气末更准确。  相似文献   
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