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1.
2.
D. Le Elizabeth Eric R. Powers Jian-Ping Bin Howard Leong-Poi N. Craig Goodman Sanjiv Kaul 《Journal of nuclear cardiology》2007,14(2):207-214
Background The mechanism by which transmyocardial revascularization (TMR) offers clinical benefit is controversial. We hypothesized that
TMR ameliorates ischemia by reversing paradoxical catecholamine-induced vasoconstriction.
Methods and Results Chronic ischemic cardiomyopathy was created in 11 dogs by placing ameroid constrictors on the proximal coronary arteries and
their major branches. Six weeks later, 35 channels were created percutaneously in the left circumflex artery region, with
the left anterior descending artery region serving as control. At rest, wall thickening and myocardial blood flow did not
change in the treated region, whereas they deteriorated in the control bed. Contractile and myocardial blood flow reserve
increased in the treated region but deteriorated in the control region. There was diminished iodine 123 metaiodobenzylguanidine
uptake and a significant reduction in noradrenergic nerves in the treated region compared with the control region, with a
corresponding reduction in tissue tyrosine hydroxylase activity.
Conclusions We conclude that the absence of a catecholamine-induced reduction in MBF reserve and contractile reserve in the TMR-treated
region with associated evidence of neuronal injury indicates that the relief of exercise-induced ischemia after TMR most likely
results from reversal of paradoxical catecholamine-induced vasoconstriction. These findings may have implications in selecting
patients who would benefit from TMR.
Supported in part by grants from the National Institutes of Health (R01-HL66034 and K-08-HL074290-01). Bethesda. Md. The radio-labeled
microspheres were provided by DuPont Pharmaceuticals, North Billerica. Mass, and the ultrasound equipment was supplied by
Philips. Andover, Mass. Dr Leong-Poi was the recipient of a Fellowship Training Grant from the Canadian Institute of Health
Research and the Heart and Stroke Foundation of Canada. 相似文献
3.
Cardiomyopathy: a late complication of hemolytic uremic syndrome 总被引:2,自引:0,他引:2
Amanda M. Walker Lee N. Benson Greg J. Wilson Gerald S. Arbus 《Pediatric nephrology (Berlin, Germany)》1997,11(2):221-222
This report describes a child who presented with classic hemolytic uremic syndrome (HUS) and 4 months later developed a life-threatening
but reversible cardiomyopathy with global cardiac dysfunction and a left ventricular ejection fraction of 14%. There was no
evidence of electrolyte abnormalities, anemia, hypertension, severe fluid overload, or viral infection. Endomyocardial biopsies
were consistent with a dilated cardiomyopathy. This paper highlights the importance of considering the diagnosis of associated
cardiomyopathy when presenting with late-onset edema following HUS.
Received February 12, 1996; received in revised form and accepted August 22, 1996 相似文献
4.
扩张型心肌病与β1 受体自身抗体关系初探 总被引:2,自引:1,他引:1
目的 探讨抗β1受体自身抗体与扩张型心肌病(DCM)之间的关系。方法 以人心脏β1受体细胞外第二环表位肽段作为抗原,应用酶联免疫吸附测定(ELISA)技术,检测28例DCM患者和32例正常人血清中β1受体的自身抗体。结果 DCM患者血清中有13例(46%)抗β1受体自身抗体阳性,正常人血清中有2例(6%),两组阳性率差异有显著性(P<0.01);DCM组自身抗体平均几何滴度为1:92,显著高于正常对照组1:20(P<0.01);DCM患者中自身抗体阳性者的抗体滴度在不同心功能间的分布差异有显著性(P<0.001)。结论 DCM患者存在着β1受体自身抗体且其滴度也明显高于正常对照组。 相似文献
5.
G. J. van Ekeren A. M. Stadhouders J. A. M. Smeitink R. C. A. Sengers 《European journal of pediatrics》1993,152(3):255-259
The objectives of this study were to describe the course of two forms of an hereditary syndrome characterised by congenital cataract, mitochondrial myopathy of heart and skeletal muscle and lactic acidosis. We also sought to determine clinical, physicochemical and histopathological data which might allow early distinction between the two forms. We compared the ages at which clinical and physicochemical signs appeared in 16 patients. In 5 patients, enzyme-histochemical and ultrastructural data of skeletal muscle were available and muscle fibre composition analysed morphometrically. In any particular family only one form of the syndrome occurred. Amongst the patients who did not survive (range 14–34 years) 4 patients died in the neonatal period and 7 died at a median age of 23 years. The median age of the survivors was 19 years (range 15–42 years). Outflow obstruction of the left ventricle was noted in four deceased patients at variable times prior to death. The other deceased patients were not examined, but the cause of death was invariably heart failure. In none of the surviving patients was outflow obstruction noted. Enzyme-histochemical and ultrastructural findings were not specific for the course of the disease. In one biopsy, taken at the age of 3.5 months from a patient who survived, strong lipid accumulation was noted. Morphometric analysis showed proliferation of the mitochondria in muscle fibres, which increased during the course of the disease. 相似文献
6.
Michiko Kawaguchi Masaaki Techigawara Takako Ishihata Tsukasa Asakura Fujiko Saito Kazuhira Maehara Yukio Maruyama 《Heart and vessels》1997,12(6):267-274
Summary The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological
changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial
changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural
changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls
without hypertension or diabetes mellitus (n=6), and patient with hypertension (n=3), diabetes mellitus (n=8), and diabetes with hypertension (n=8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures
were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials
showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement
membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater
in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in
the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective
of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial
cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells
and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately,
to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension. 相似文献
7.
急性心肌梗塞错误溶栓治疗12例分析 总被引:1,自引:0,他引:1
自1993年12月至1995年8月,对155例急性心肌梗塞(AMI)病人进行溶栓治疗,12例发生误溶(7.7%)。其中早期复极综合征4例,室壁瘤2例,心肌炎1例,心肌病1例,完全性左束支阻滞1例,间歇性左前分支阻滞互例,其它2例。本文分析了误溶病例与AMI的鉴别要点,并提出了减少误溶,提高诊疗水平的措施。 相似文献
8.
背景 血栓栓塞(TE)事件是肥厚型心肌病(HCM)的重要并发症。目前针对HCM患者TE事件的风险预测,仅国外学者构建了两个模型:HCM Risk-CVA及French HCM score,然而,现有研究发现HCM Risk-CVA模型对于中国HCM患者的临床价值较为有限。目的 本研究拟构建适合中国HCM患者的TE事件风险预测模型。方法本研究系回顾性队列研究,收集2010—2018年在四川大学华西医院就诊的537例HCM患者的病例资料。本研究通过电话随访或电子病历系统查询患者就诊记录,每6~12个月随访1次,直至出现终点事件或死亡或研究拟定的评估日期(2019-12-31),终点事件定义为复合性TE事件。采用单因素和多因素Cox回归分析构建风险预测模型,并使用自助重抽样的方法进行内部验证。结果 537例患者中,24例患者有不同程度的数据缺失,最终纳入513例患者。中位随访时间为4.2(1.3,6.2)年,随访过程中42例(8.18%)发生TE事件,年发病率为2.10%[95%CI(1.47%,2.73%)]。根据多因素Cox回归模型构建TE事件风险预测模型,最终纳入年龄、既往TE事件、心... 相似文献
9.
背景 2型糖尿病可增加患者心血管疾病的早发风险,对健康构成重大威胁。阐明2型糖尿病对扩张型心肌病患者预后的影响,有利于指导患者的管理。目的 探讨2型糖尿病对扩张型心肌病患者预后的影响。方法 回顾性选取广西医科大学第一附属医院心血管内科2015年1月至2020年5月收治的313例扩张型心肌病患者为研究对象。根据患者是否罹患2型糖尿病将患者分为糖尿病组(n=66)和非糖尿病组(n=247),收集患者一般资料、实验室检查指标并进行随访,随访终点事件为全因死亡,随访日期截至2021-12-31。采用landmark比较两组患者的生存率。建立多因素Cox比例风险回归模型,探究扩张型心肌病患者全因死亡的影响因素。结果 Landmark分析结果显示,糖尿病组和非糖尿病组扩张型心肌病患者随访1年内的生存率比较,差异无统计学意义(χ2=1.520,P=0.218);随访1年后,糖尿病组扩张型心肌病患者的生存率低于非糖尿病组(χ2=4.414,P=0.036)。分段拟合法构建的多因素Cox比例风险回归分析显示,收缩压[HR=0.965,95%CI(0.948,0.982)]、N末端B型利钠肽原[HR=9.... 相似文献
10.
R. Christen R. Morant J. Schneider R. Jenni J. Fehr 《Journal of molecular medicine (Berlin, Germany)》1989,67(6):358-365
Summary A female patient is described in whom the diagnosis of idiopathic hypereosinophilic syndrome (HES) with heart disease and peripheral neuropathy was made at the age of 32 years. Although prednisone induced a prompt and longstanding complete hematological remission, progressive and eventually intractable heart failure developed, and the patient died 6 years later. Endomyocardial biopsy at diagnosis showed infiltration with intact and disintegrated eosinophils and Charcot-Leyden crystals. Echocardiographic follow-up (including Doppler-Echocardiography) revealed mitral regurgitation with thickening and impaired motility of the posterior mitral leaflet, as well as progressive dilated cardiomyopathy. At autopsy, a diffuse interstitial fibrosis with patchy prominence in an eccentric hypertrophic and highly dilated heart was found. There were no significant endocardial thickening and no mural thrombi. In contrast to the findings of the initial endomyocardial biopsy, autopsy revealed no eosinophilic infiltrate.In this case, eosinophil-induced heart disease manifested as dilated cardiomyopathy, without endocardial fibrosis as originally described by Löffler. We speculate, that eosinophils have been deposited predominantly in the myocard at an early stage of disease, and — activated locally — secreted their granule proteins producing an initial damage to capillary endothelial cells and myocytes. After prednisone-induced clearance of eosinophils from blood and tissues, progressive, self-perpetuating interstitial fibrosis of the myocard and loss of myocytes eventually resulted in end-stage dilated cardiomyopathy.Abkürzungsverzeichnis HES
idiopathic hypereosinophilic syndrome
- UBBC
unsaturated vitamin B12 binding capacity
- ECP
eosinophil cationic protein
- MBC
major basic protein
- EDD
end-diastolic diameter of the left ventricle
- LA
left atrium diameter
- LVEDP
left ventricular end-diastolic pressure
- NIH
National Institutes of Health 相似文献