全文获取类型
收费全文 | 62005篇 |
免费 | 3963篇 |
国内免费 | 999篇 |
专业分类
耳鼻咽喉 | 475篇 |
儿科学 | 1570篇 |
妇产科学 | 1595篇 |
基础医学 | 7320篇 |
口腔科学 | 1078篇 |
临床医学 | 5556篇 |
内科学 | 14496篇 |
皮肤病学 | 1144篇 |
神经病学 | 5600篇 |
特种医学 | 1992篇 |
外国民族医学 | 2篇 |
外科学 | 7722篇 |
综合类 | 2157篇 |
现状与发展 | 1篇 |
一般理论 | 12篇 |
预防医学 | 4186篇 |
眼科学 | 974篇 |
药学 | 5073篇 |
8篇 | |
中国医学 | 1030篇 |
肿瘤学 | 4976篇 |
出版年
2023年 | 542篇 |
2022年 | 1359篇 |
2021年 | 2154篇 |
2020年 | 1330篇 |
2019年 | 1585篇 |
2018年 | 1753篇 |
2017年 | 1369篇 |
2016年 | 1414篇 |
2015年 | 1818篇 |
2014年 | 2444篇 |
2013年 | 3071篇 |
2012年 | 4171篇 |
2011年 | 4364篇 |
2010年 | 2520篇 |
2009年 | 2210篇 |
2008年 | 3570篇 |
2007年 | 3610篇 |
2006年 | 3351篇 |
2005年 | 3212篇 |
2004年 | 2880篇 |
2003年 | 2533篇 |
2002年 | 2317篇 |
2001年 | 1517篇 |
2000年 | 1407篇 |
1999年 | 1333篇 |
1998年 | 579篇 |
1997年 | 442篇 |
1996年 | 428篇 |
1995年 | 353篇 |
1994年 | 320篇 |
1993年 | 259篇 |
1992年 | 713篇 |
1991年 | 605篇 |
1990年 | 571篇 |
1989年 | 580篇 |
1988年 | 484篇 |
1987年 | 437篇 |
1986年 | 417篇 |
1985年 | 333篇 |
1984年 | 279篇 |
1983年 | 230篇 |
1982年 | 131篇 |
1981年 | 109篇 |
1979年 | 220篇 |
1978年 | 137篇 |
1977年 | 118篇 |
1974年 | 128篇 |
1973年 | 130篇 |
1972年 | 129篇 |
1971年 | 112篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
Neurological Sciences - Bladder and urethra are innervated peripherally by pelvic parasympathetic, lumbar sympathetic and pudendal nerves; but a complex of brain networks is involved in the... 相似文献
132.
Correlation of serum metalloproteinase levels with lung cancer metastasis and response to therapy. 总被引:14,自引:0,他引:14
S Garbisa G Scagliotti L Masiero C Di Francesco C Caenazzo M Onisto M Micela W G Stetler-Stevenson L A Liotta 《Cancer research》1992,52(16):4548-4549
Cancer cells elaborate metalloproteinases which may play a role in invasion and metastasis. The serum level of the M(r) 72,000 type IV collagenase (MMP-2) was measured in 87 lung cancer patients. Stage IV cancer levels were significantly elevated (P less than 0.0001) compared to normal sera. A significant difference (P less than 0.01) was found between enzyme levels in the presence versus the absence of distant metastasis. For 29 patients treated with combination chemotherapy, a positive relationship was noted between response failure and elevated enzyme levels. Serum metalloproteinase levels may provide information relevant to prognosis as well as treatment decisions. 相似文献
133.
Sylvie Di Filippo Bertrand Semiond Ricardo Roriz Francois Sassolas Marie José Raboisson André Bozio 《The Journal of heart and lung transplantation》2003,22(8):876-882
BACKGROUND: Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease. METHODS: Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage. RESULTS: All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE. CONCLUSIONS: DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population. 相似文献
134.
超声心动图对62例房间隔缺损封堵术后心功能变化的评价 总被引:5,自引:0,他引:5
目的:应用超声心动图评价房间隔缺损(ASD)封堵术前后左、右心室功能的变化。方法:对62例成功施行经皮穿刺ASD封堵术的患者进行研究。所有患者在术前、术后1周及1个月分别进行超声心动图检查.观察心脏大小及功能的改变。结果:ASD封堵术后,左室舒张末期前后径、左室舒张末期容积、左室每搏量及左室射血分数增大,而左室收缩末期容积未见明显改变;右室舒张末期前后径、右室舒张末期容积、右室收缩末期容积、右室每搏量、右室射血分数及右室心肌工作指数均减小。结论:经皮穿刺ASD封堵治疗既可减轻右室容量负荷,改善右室功能,也可改善左室的收缩功能:超声心动图对ASD封堵前后心脏血流动力学评价及疗效的观察起了重要的作用。 相似文献
135.
Vincenzo La Milia Salvatore Di Filippo Monica Crepaldi Simeone Andrulli Lucia Del Vecchio Pietro Scaravilli Giovambattista Virga Francesco Locatelli 《Nephrology, dialysis, transplantation》2004,19(7):1849-1855
BACKGROUND: Sodium removal (NaR) may have a major impact on the survival of peritoneal dialysis patients. The dialysate/plasma sodium concentration ratio (D/P(Na)) is an indirect index of transcellular water transport by aquaporin channels, and thus of ultrafiltration. Sodium concentration can be assessed by means of flame photometry (F), and direct (D-ISE) or indirect ion-selective electrodes (I-ISE), but these methods have different properties. I-ISE is being used increasingly in clinical laboratories. The aim of this study was to evaluate NaR and D/P(Na) using the three different measurement methods. METHODS: We performed peritoneal equilibration tests (PETs) in 44 peritoneal dialysis patients and calculated the NaR. We also calculated D/P(Na) during the test; plasma and dialysate sodium concentrations were measured by F, D-ISE and I-ISE. RESULTS: NaR was lower (P<0.001) with D-ISE (69+/-29 mmol) than with F (81+/-29 mmol) or I-ISE (79+/-28 mmol). D/P(Na) was also lower at baseline (0.92+/-0.02 vs 0.95+/-0.02 and 0.95+/-0.02; P<0.001), after 60 min (0.87+/-0.03 vs 0.90+/-0.03 and 0.90+/-0.03; P<0.001) and at the end of PET (0.88+/-0.04 vs 0.92+/-0.04 and 0.92+/-0.04; P<0.001) when measured by D-ISE in comparison with F and I-ISE, respectively. CONCLUSIONS: NaR and D/P(Na) were lower when measured by the D-ISE method compared with the F and I-ISE methods. NaR and D/P(Na) were similar when measured by F or I-ISE. I-ISE can be used reliably in the evaluation of NaR and D/P(Na) in everyday clinical practice of peritoneal dialysis. 相似文献
136.
M Luigia Vaccario Maria A Valenti Anna Carullo Rossella Di Bartolomeo Salvatore Mazza 《Clinical EEG》2003,34(1):15-17
Benign neonatal sleep myoclonus (BNSM), characterized by myoclonic jerks of the extremities only in non-REM sleep, occurs in the first months of life with spontaneous disappearance within 3-4 months. We examined five siblings with typical BNSM, at the 3-10 years follow-up neurological examination. Psychomotor development, cognitive functions and EEG were completely normal. These cases confirm that BNSM is a self limited and nonepileptic disorder. 相似文献
137.
138.
A Vetrani F Fulciniti G Di Benedetto P Zeppa G Troncone A Boscaino G de Rosa L Palombini 《Cancer》1992,69(3):736-740
A series of 1153 fine-needle aspiration biopsies (FNAB) of breast masses obtained during the period 1985 to 1988 in one institution was examined. The following diagnostic accuracy values were found: sensitivity, 93.0%; specificity, 92.4%; predictive positive value, 93.7%; and efficiency, 92.8%. These results were compared with a previously published series for the period 1976 to 1984. The diagnostic accuracy values did not differ significantly between the two series. 相似文献
139.
A. Rocco J. Afra M. Toscano G. Sirimarco L. Di Clemente M. Altieri G. L. Lenzi V. Di Piero 《European journal of neurology》2007,14(12):1378-1382
The intensity dependence of the auditory-evoked potentials (IDAP) is inversely related to serotonergic tone. Depression is frequently observed after stroke, associated with cognitive impairment and increased mortality. Aim of this study was to investigate the serotonergic tone in acute stroke patients by IDAP. Consecutive patients with an acute stroke admitted in our stroke unit were evaluated using clinical and instrumental examinations and compared with healthy controls. The IDAP was calculated as the linear amplitude/stimulus intensity function (ASF) slope, by measuring the peak-to-peak amplitude of Nl-P2 on four blocks of different stimulus intensities. Twenty patients were enrolled; 11 had a right brain infarction; nine had depressive symptoms (DS). The ASF slope of the auditory-evoked potentials was markedly increased in stroke patients compared with controls ( P = 0.021). Stroke patients with DS had a significant steeper ASF slope than controls ( P = 0.017). There was no statistical difference in ASF slope between stroke patients without DS and controls. Post-stroke depression pathophysiology is still debated. Our study suggests that in acute stroke patients with DS, there is a direct involvement of the serotonergic system, regardless the degree of disability and the site of the lesion. 相似文献
140.
Risk of death from acute pancreatitis 总被引:5,自引:0,他引:5
Giorgio Talamini Claudio Bassi Massimo Falconi Nora Sartori Luca Frulloni Vincenzo Di Francesco Sergio Vesentini Paolo Pederzoli Giorgio Cavallini 《Journal of gastrointestinal cancer》1996,19(1):15-24
Summary
Conclusions
The analysis of all the data available in 192 patients at 24 h from admission shows that only serum glucose above 250 mg/dL
(13.88 mmol/L) and serum creatinine above 2 mg/dL (176.8 μmol/L) are prognostic factors of death (P<0.0001). When, however, pathological chest X-rays are also considered in a subset of 149 patients, these and serum creatinine
are prognostic factors of death with odds ratios of 2.9 (95% CL 1.3–6.3) and 9.4 (95% CL 2.2–40.7), respectively (P<0.0001).
Background In patients suffering from acute pancreatitis, neither Ranson scores nor Glasgow criteria evaluation at 24 h yield a sufficiently
reliable prognosis of the risk of death from the first acute attack.
Methods After excluding posttraumatic, postsurgical, and post-ERCP acute pancreatitis, we selected 192 consecutive patients admitted
in the first instance to our center for a first attack, distinguishing between patients who died and patients who survived.
We used Cox's model to analyze the prognostic weight of variables available within 24 h of admission (sex, age, alcohol intake,
smoking habits, 17 biochemical tests, body mass index, chest X-rays, body temperature, and shock status).
Results Seventeen (8.8%) patients died; mortality showed a decreasing trend over the period of years considered and was correlated,
among other things, with necrotizing type of pancreatitis, idiopathic etiology, and shock status on admission. 相似文献