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71.
The diabetic neuropathic ulcer is typically slow to heal and recurrent. Macrovascular insufficiency is usually excluded as foot pulses are present and ankle:brachial pressure ratios are not decreased. These assessments cannot however exclude more distal vascular disease. Digital pressure measurements enable a reliable assessment of the distal peripheral vascular status to be made. The aim of this study was therefore to use toe pressures to assess the contribution of distal ischaemia in the pathogenesis of the neuropathic ulcer. Sixteen diabetic patients with recurrent neuropathic foot ulceration had their toe pressures compared to 10 neuropathic patients without a history of foot ulceration, 10 diabetic control subjects, and 11 normal subjects. Four non-diabetic patients with neuropathy and foot ulceration were also assessed. All subjects had ankle:brachial pressure indices ≧ 1. Toe pressure was assessed using laser Doppler flowmetry to record the return of skin blood flow. The toe:brachial pressure index (TBI) was then calculated. The diabetic patients with a history of recurrent neuropathic ulceration, had the lowest mean TBI, 0.63 ± 0.14 (SD), compared to the non-ulcerated diabetic neuropathy patients, the diabetic control subjects, and the normal subjects. 0.84 ± 0.11, 0.82 ± 0.1, and 0.81 ± 0.07, p < 0.01, respectively. Three of the four non-diabetic patients with neuropathic foot ulceration also had an abnormally low TBI. Reduced toe pressure measurements are thus found to be associated with neuropathic foot ulceration. The contribution of distal ischaemia in the pathogenesis of the diabetic neuropathic foot ulcer needs to be evaluated. One hundred and eight non-insulin-dependent diabetic patients who had been tested for autonomic dysfunction in 1984/85 were re-evaluated 5 years later. Autonomic function was assessed by means of four cardiovascular tests (heart rate variation during deep breathing and standing, and blood pressure variation after standing and sustained handgrip). Eighteen subjects were lost to follow-up; in the 90 patients who completed the study, both the deep breathing and the handgrip test significantly worsened (respectively from 13.7 ± 7.8 to 11.6 ± 6.3 beats min?1 p < 0.01, and from 16.9 ± 8.2 to 12.7 ± 7.1 mmHg, p < 0.001), whereas both the 30:15 ratio and the variation of blood pressure on standing did not change. The impairment of a comprehensive evaluation score (from 2.5 ± 1.7 to 3.0 ± 1.5; p < 0.05) also confirmed the gradual deterioration of autonomic function over the study period.  相似文献   
72.
We studied the long-term outcome of 268 patients suffering fromdiabetic end-stage renal disease (DM-ESRD) treated with long-termhaemodialysis between 1978 and 1991, with special emphasis onvisual acuity as well as the heterogeneity of DM-ESRD The 50%patient survival on haemodialysis was 60 months. Visual disturbanceswere found in 73.1% (392/536) of eyes at the start of haemodialysis.Chronological assess ment of visual acuity demonstrated thestabilization of visual acuity and 87.1% (364/418) of eyes werestable, 4.8% (20/418) were improved, and 8.1% (34/418) wereaggravated in the long term respectively. The change of visualacuity was frequently seen in the short term, and rapid shiftsof body fluid to correct overhydration induced abrupt changesof glycaemic control as well as retraction of macular oedema.Hence it might be one of the factors affecting rapid changeof visual acuity in the short term. Meanwhile, long-term deterioration of visual acuity resulted from either hyperten sionunresponsive to medical treatment or poor glycaemic control.Some DM-ESRD patients had only background retinopathy at thestart of haemodialysis and these were likely to have the nephroscleroticglomerular lesion. They were old, not nephrotic and had a milddegree of diabetes during the predialysis stage. Thus, DM-ESRDpatients seem to have some heterogeneity in their clinical characteristics,and old DM-ESRD patients with only background retinopathy havethe appearance of diabetic macroangiopathy rather than microangiopathy.  相似文献   
73.
74.
刘春  蹇文渊  段俊国 《中国全科医学》2023,26(15):1847-1856
背景 近年来,人工智能(AI)在医学领域发展迅速,在糖尿病视网膜病变(DR)中的应用范围不断扩展。目的 通过文献计量分析总结AI在DR领域的应用情况,阐明AI在DR领域相关研究的现状、热点和新兴趋势,以期为未来的研究提供思路。方法 以Web of Science数据库为来源,检索建库至2022-11-04的AI应用于DR领域的相关文献,运用CiteSpace软件对纳入文献进行发文量、国家、机构、作者、共被引和关键词的文献计量学分析。结果共获得1 770篇文献,2011年1月至2022年11月发文量总体呈上升趋势,2021年发文量达峰值(402篇)。中国是发文量(440篇)位居第1的国家,英国为中心性(0.26)最高的国家。机构合作网络图谱共纳入436家机构,以中山大学和首都医科大学为代表。作者合作网络图谱共纳入601位作者,以JIA Y L和HWANG T为代表。GULSHAN V、ABRàMOFF M D与TING D W 3位高被引作者对该领域做出了重要贡献。Ophthalmology、Invest Ophth Vis Sci和Ieee T Med Imaging是AI应用于DR领...  相似文献   
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76.
Microalbuminuria is a predictor of renal and cardiovascular disease in both type 1 (insulin-dependent) and type 2 (insulin-independent) diabetes. We report on a screening programme for microalbuminuria at a diabetes clinic in Italy. All diabetic patients without Albustix-positive proteinuria attending the clinic between April and September 1991 were screened. Microalbuminuria was defined as a urinary albumin/creatinine ratio, on an early morning sterile urine sample, >3 in at least two consecutive urine collections. Three hundred and fifty patients, 45 (20 female, 25 female) type 1 and 305 (145 male, 160 female) type 2 diabetics, were examined. The age range was 18–42 years and 36–73 years and duration of diabetes 1–24 and 1–35 years for type 1 and type 2 diabetic patients respectively. Blood pressure, lipids, glycosylated haemoglobin, body mass index and insulin dose, where appropriate, were measured in all patients. Microalbuminuria was found in 8 (22%) of the type 1 diabetics. These patients had a longer duration of diabetes (17.5 vs 7.4 years,P<0.001), higher diastolic blood pressure (86±2.1 vs 76±2.6 mmHg,P<0.05) and an increased total serum cholesterol level (203±23 vs 180±25 mg/dl,P<0.05) compared with diabetic patients with microalbuminuria. Of the type 2 diabetic patients 95 (33%) were found to have microalbuminuria and 210 (69%) nor-moalbumiuria. The prevalence of hypertension (defined blood pressure >140/90 mmHg or antihypertensive treatment) and of dyslipidaemia (defined as total cholesterol >200 and triglycerides >170 or hypolipidaemic treatment) were significantly higher (P<0.001 and 0.01 respectively) in patients with microalbuminuria. This study shows a prevalence of microalbuminuria in type 1 and type 2 diabetic patients similar to that reported in surveys of diabetes clinic outpatients in northern Europe. The association between microalbuminuria and recognized risk factors for cardiovascular and renal disease justifies screening programmes for microalbuminuria for early detection of at-risk diabetic patients and for the implementation of preventive therapeutic measures.  相似文献   
77.
The role of dietary factors in patients with type 1 (insulin-dependent) diabetes is reviewed by examining three different aspects: the effect of an acute protein load, the effect of dietary protein restriction on the progression of nephropathy and the metabolic effects of low-protein diets. After an acute protein load some impairment of the renal functional reserve may be observed only in patients with type 1 diabetes and overt nephropathy. However, the renal functional reserve is not able to give useful indications of the extent of renal damage and the prognosis of the disease. Both short-term and long-term dietary protein restriction are followed by a significant decrease in glomerular filtration rate (GFR) and albuminuria in type 1 diabetics with incipient nephropathy. In patients with overt nephropathy the long-term administration of a low-protein diet is followed by significant reductions in the rate of decline of GFR and in urinary protein excretion only when started at GFR values higher than 45 ml/min. The rate of functional deterioration when dietary treatment is prescribed seems critical in modulating the effects of a low-protein diet. In addition, low-protein diets may exert important metabolic and clinical effects beyond their supposed effect on progression. Clearly, an adequate dietary regimen is only part of the medical treatment in patients with diabetic nephropathy.  相似文献   
78.
Of all the electroretinogram (ERG) components (a-wave, b-wave, and oscillatory potentials) only one oscillatory potential, OP2, was found to be significantly correlated with the absolute intensity of the flash stimulus (i.e., the intensity of the stimulus irrespective of the state of retinal adaptation). Our finding was further confirmed in single cell recordings of lateral geniculate unit activity in rabbits in which peak time of OP2 was found to correlate better with the geniculate activity. For these reasons we have identified OP2 as the intensity coding oscillatory potential of the ERG. In order to investigate if this new feature could have some clinical significance, we examined photopic ERGs recorded from patients affected with various retinopathies. In most instances the peak time of OP2 paralleled that of the b-wave, that is, in the ERG with delayed b-wave the peak time of OP2 was also delayed, while in ERGs with normal b-wave peak time the peak time of OP2 was also normal. However, in some conditions (especially in cone-rod diseases) a delayed OP2 was found in ERGs with normal b-wave peak times.  相似文献   
79.
Visual acuity, color vision, pattern-visual-evoked-potentials (P-VEPs) and pattern-electroretinograms (P-ERGs) were measured in 13 diabetic subjects before, and 24 hours and 5 weeks after blue-green argon laser treatment. As control, the same examinations were performed in 7 normal subjects and 7 diabetic patients before and after slit lamp examination with the Goldman three mirror contact lens.Visual acuity and P-ERG amplitudes were significantly reduced one day after the laser treatment, while 5 weeks after the laser coagulation, visual acuity and P-ERG amplitudes recovered to pretreatment values. The control group showed no significant changes after slit lamp examination. Since fluorescein angiography revealed no macular changes after laser treatment, the possibility of a reversible functional light damage after blue-green argon laser coagulation (ALC) is discussed.This study was supported by the Medizinisch - Wissenschaftlicher Fonds des Bürgermeisters der Bundeshauptstadt Wien.  相似文献   
80.
目的探讨2型糖尿病(DM)患者血管内皮细胞损伤与血白介素6(IL-6)的关系及其意义。方法检测45例2型DM患者及20例正常人外周血IL-6和循环内皮细胞(CEC)水平并进行比较。结果①2型DM患者血IL-6和CEC水平高于正常人(P<0.05);②早期糖尿病肾病患者血CEC水平明显高于单纯糖尿病患者(P<0.01);③多元逐步回归分析显示CEC与血IL-6水平和尿蛋白排泄率(UAER)显著相关,标准偏回归系数β分别为0.264(P=0.033)和0.545(P=0.000)。结论2型糖尿病血管内皮细胞损伤与体内IL-6升高有密切关系,并在糖尿病肾病的发病过程中起一定作用。  相似文献   
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