全文获取类型
收费全文 | 122536篇 |
免费 | 7961篇 |
国内免费 | 3518篇 |
专业分类
耳鼻咽喉 | 449篇 |
儿科学 | 2534篇 |
妇产科学 | 1524篇 |
基础医学 | 7623篇 |
口腔科学 | 385篇 |
临床医学 | 16272篇 |
内科学 | 35273篇 |
皮肤病学 | 187篇 |
神经病学 | 4474篇 |
特种医学 | 7323篇 |
外国民族医学 | 9篇 |
外科学 | 12235篇 |
综合类 | 22416篇 |
现状与发展 | 8篇 |
预防医学 | 5242篇 |
眼科学 | 1199篇 |
药学 | 10973篇 |
91篇 | |
中国医学 | 4266篇 |
肿瘤学 | 1532篇 |
出版年
2024年 | 290篇 |
2023年 | 1835篇 |
2022年 | 3378篇 |
2021年 | 4841篇 |
2020年 | 4653篇 |
2019年 | 3992篇 |
2018年 | 4069篇 |
2017年 | 3936篇 |
2016年 | 4200篇 |
2015年 | 4243篇 |
2014年 | 8412篇 |
2013年 | 9342篇 |
2012年 | 7049篇 |
2011年 | 7445篇 |
2010年 | 6331篇 |
2009年 | 5960篇 |
2008年 | 5892篇 |
2007年 | 6050篇 |
2006年 | 5512篇 |
2005年 | 4660篇 |
2004年 | 3899篇 |
2003年 | 3449篇 |
2002年 | 2840篇 |
2001年 | 2676篇 |
2000年 | 2149篇 |
1999年 | 1886篇 |
1998年 | 1707篇 |
1997年 | 1692篇 |
1996年 | 1402篇 |
1995年 | 1367篇 |
1994年 | 1169篇 |
1993年 | 926篇 |
1992年 | 906篇 |
1991年 | 726篇 |
1990年 | 643篇 |
1989年 | 555篇 |
1988年 | 531篇 |
1987年 | 466篇 |
1986年 | 404篇 |
1985年 | 500篇 |
1984年 | 430篇 |
1983年 | 220篇 |
1982年 | 297篇 |
1981年 | 247篇 |
1980年 | 237篇 |
1979年 | 161篇 |
1978年 | 122篇 |
1977年 | 101篇 |
1976年 | 87篇 |
1975年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
ABSTRACT A follow-up examination was performed one month to 20 years after adrenalectomy in 28 cases with surgically treated primary aldosteronism due to adrenal adenoma. The mean age at diagnosis was 45, and the mean duration of hypertension seven years. Severe hypertension with a diastolic blood pressure of 130 mmHg or more was observed in 35%. Postoperatively cerebrovascular catastrophe developed in two cases, both of which belonged to the group of patients with severe hypertension. Normalization of blood pressure was observed in 70% and in the remaining subjects the blood pressure was lower than at diagnosis. The blood pressure response to adrenalectomy appeared unpredictable in view of such parameters as the initial blood pressure, age at diagnosis, and duration of the hypertensive state. Toxicosis during pregnancy and metrorrhagia was observed with unexpectedly high frequency in this study population. Low ambulatory plasma renin activity was recorded at the follow-up in 15 out of 18 subjects studied in the absence of evidence of hyperaldosteronism. 相似文献
92.
Gü l Gü rsel Haluk Tü rktas Nahide G k ora Ishak
zel Tekin 《The Journal of asthma》1997,34(4):313-319
The aim of the present study was to investigate whether sputum eosinophil cationic protein (ECP) concentrations could be a useful marker in the differential diagnosis between intrinsic asthma and chronic obstructive pulmonary disease (COPD). For this purpose total blood eosinophil counts were obtained and concentrations of serum and sputum ECP from 10 nonatopic asthmatics with a mild attack and 9 COPD patients with acute exacerbation were measured by radioimmunoassay. Mean serum ECP concentration was 54.3 ± 23.0 g/L in the asthmatic group and 83.3 ± 79.2 g/L in the COPD group (p: n.s.). In the group of asthmatics mean sputum ECP level was 984.5 ± 1245.5 mg/L/g sputum and in the COPD group it was 417.5 ± 363.5 mg/L/g sputum. There was no significant difference in sputum ECP levels between patients with asthma and COPD. We conclude that neither sputum nor serum ECP levels are useful markers in differential diagnosis of asthma attack and acute exacerbation of COPD. 相似文献
93.
Paradoxical hypertension is a relatively common complication of surgical repair of coarctation of the aorta. An early phase of systolic hypertension has been ascribed to elevated levels of norepinephrine. Activation of the renin-angiotensin system from sympathetic stimulation has been implicated in a later phase of systolic and diastolic hypertension that can result in mesenteric arteritis. The use of a rapidly acting, titratable intravenous alpha- and beta-adrenergic blocker, such as labetalol hydrochloride, addresses both of these neurohormonal mechanisms. In the intravenous form, it would appear to be an excellent choice for the management of early postoperative hypertension and it can be converted to the oral form in cases of persistent hypertension. We report for the first time the use of labetalol in two young patients for the control of paradoxical hypertension following coarctation repair. 相似文献
94.
目的:分析血脂代谢异常与冠状动脉狭窄程度的关系.方法:对366例因胸痛而就诊的患者行选择性冠状动脉造影,按冠状动脉狭窄程度分为正常对照组、单支病变组、双支病变组、多支病变组.同时观察患者血脂各成分,并对各组指标进行统计学分析.结果:总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C),在各组之间存在差异,尤其多支病变组与正常组之间差异显著(P<0.01).TC、TG、LDL-C随冠状动脉病变加重而增加,HDL-C随冠状动脉病变加重而减少,LDL-C与冠状动脉狭窄程度呈正相关,HDL-C与冠状动脉狭窄程度呈负相关.结论:血脂代谢紊乱与冠状动脉狭窄的发生发展有内在的联系,对于预测有无冠状动脉病变及其进展有一定临床意义. 相似文献
95.
肺癌组织中血管内皮生长因子受体Flt1及KDR的表达及其与肿瘤转移和预后的关系 总被引:1,自引:1,他引:0
①目的 探讨肺癌中血管内皮生长因子受体Flt1、KDR的表达与其转移及预后的关系。②方法 应用免疫组织化学PowerVisionTM PV90 0 0法 ,测定 75例肺癌标本中Flt1、KDR的表达。③结果 肺癌组织中Flt1、KDR的表达较为广泛 ,主要位于肿瘤细胞胞浆及胞膜上 ,纤维母细胞和血管内皮细胞胞浆中亦有表达。Flt1、KDR在肿瘤细胞中的阳性率均显著高于在间质纤维母细胞中的表达 (χ2 =6 .0 7、5 .88,P <0 .0 5 )。肿瘤细胞及纤维母细胞中该两种受体的阳性率在不同年龄、不同性别及不同病理类型、不同病理分级之间差异均无显著性 (χ2 =0 .0 1~4 .84 ,P >0 .0 5 ;P =0 .2 9~ 0 .79)。肿瘤细胞中Flt1、KDR的阳性表达率在 3组不同大小的肿瘤间差异均有显著性(χ2 =1 0 .35、7.2 9,P <0 .0 5 ) ,而纤维母细胞中差异均无显著性 (χ2 =2 .86、2 .5 6 ,P >0 .0 5 ) ;肿瘤细胞及纤维母细胞中Flt1、KDR的阳性率在淋巴结有、无转移两组间的差异均有显著性 (χ2 =4 .72~ 9.32 ,P <0 .0 5 ) ,在 3组不同术后生存时间病人间亦均有显著性差异 (χ2 =8.81~ 1 9.1 9,P <0 .0 5 )。肿瘤细胞中Flt1、KDR的表达呈极显著性正相关 (r =0 .4 4 ,P <0 .0 1 )。④结论 肺癌的生长主要依赖自分泌机制 ,联合检测Flt1、KDR可能对肺癌转移 相似文献
96.
D M Reboussin D C Goff E W Lipkin D M Herrington J Summerson M Steffes R J Crouse L Jovanovic M N Feinglos J L Probstfield M A Banerji D J Pettitt J Williamson 《Diabetic medicine》2004,21(10):1082-1089
OBJECTIVE: To examine the effect of short-term improvements in glycaemic control on brachial artery endothelial function as a marker of cardiovascular health. METHODS: Persons with Type 2 diabetes who were poorly controlled on oral therapy were randomly assigned to monotherapy with repaglinide or combination therapy with repaglinide plus metformin. Brachial artery flow-mediated vasodilation was assessed by ultrasonography at randomization and following 16 weeks of therapy. The primary outcome was change in brachial artery endothelial function from baseline. Comparison of randomized groups was a secondary aim. RESULTS: Eighty-six participants were randomized, and 83 were followed to study completion. Post occlusion brachial artery vasodilation was 3.74% at baseline and 3.82% following 16 weeks of therapy (P = 0.77). The treatment effect was 0.08% (95% CI: -0.48%, 0.64%). No difference was seen between treatment groups (P = 0.69). Overall, A1C was reduced from 8.3% to 7.0%, with a greater reduction in the combination therapy group (from 8.4% to 6.7%) than in the monotherapy group (from 8.3% to 7.3%, p for difference between groups = 0.01). Statistically significant reductions were observed in fasting glucose, and plasminogen activator inhibitor-1. Statistically significant increases were observed for fasting insulin, uric acid, weight and BMI. CONCLUSIONS: Brachial artery endothelial function was not influenced by short-term improvements in glycaemic control. The CONTROL DM group was successful in lowering A1C. Future research should explore more intensive and longer-lasting improvements in glycaemic control on endothelial function. Some data previously published in abstract form (Diabetes 2001; 50 (Suppl. 2): A217). 相似文献
97.
Purpose: To compare the short-term efficacy and side effects of betaxolol and timoloi in treatment of primary open angle glaucoma or ocular hypertension. Methods: Fourteen patients with newly diagnosed early primary open angle glaucoma or ocular hypertension were included.Each patient received 0.5% timoloi and 0.5% betaxolol twice daily for four weeks in two phases. Between two courses of treatment there was four weeks wash out period. At the end of study the effect of these two drugs on intraocular pressure, mean arterial blood pressure,pulse rate,basic tear secretion and ocular symptoms were evaluated and statistically analyzed,using wilcoxon and chi-squar test.RESULTS:The study was performed on fourteen patients with baseline IOP of 26.7 ±1.5 mmHg.After four weeks treatmem,timoiol and betax-olol reduced IOP by 7.8±1.2mmHg or 29% and 6.1±1.3mmHg or 23%, respectively (P<0.001). The difference between two groups was significant(P<0.001). Mean arterial blood pressure was reduced with betaxolol and tim 相似文献
98.
L Madacsy A Yasar T Tulassay A Körner J Kelemen M Hóbor M Miltényi 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(4):414-417
Twenty-four-hour blood pressure and heart rate measurements were carried out in 14 newly diagnosed diabetics and in 28 diabetics with 5–13 years' duration of the disease; 8 healthy children were used as controls. Mean arterial blood pressure increased at night in 5, decreased slightly (less than 10%) in 5 and decreased markedly (more than 10%) in 18 diabetics with longer duration of the disease. The diurnal-nocturnal differences in heart rates were significantly lower in diabetics with relative "nocturnal hypertension" compared to the control group ( p < 0.05). A significant negative correlation was found between maximal arterial blood pressure during physical exercise and the diurnal-nocturnal differences in mean arterial blood pressure in diabetics ( r =−0.58; p < 0.02). In conclusion, we found elevated nocturnal blood pressure in a subgroup of children with longer duration of diabetes and without increased albumin excretion. However, longitudinal studies of blood pressure profiles are needed to identify the candidates for diabetic vasculopathy among diabetic children. 相似文献
99.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae. 相似文献
100.