全文获取类型
收费全文 | 8794篇 |
免费 | 530篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 122篇 |
儿科学 | 162篇 |
妇产科学 | 153篇 |
基础医学 | 1096篇 |
口腔科学 | 858篇 |
临床医学 | 679篇 |
内科学 | 1979篇 |
皮肤病学 | 199篇 |
神经病学 | 648篇 |
特种医学 | 264篇 |
外科学 | 901篇 |
综合类 | 24篇 |
一般理论 | 4篇 |
预防医学 | 995篇 |
眼科学 | 159篇 |
药学 | 683篇 |
中国医学 | 97篇 |
肿瘤学 | 339篇 |
出版年
2023年 | 80篇 |
2022年 | 188篇 |
2021年 | 345篇 |
2020年 | 246篇 |
2019年 | 288篇 |
2018年 | 349篇 |
2017年 | 223篇 |
2016年 | 251篇 |
2015年 | 318篇 |
2014年 | 454篇 |
2013年 | 472篇 |
2012年 | 668篇 |
2011年 | 813篇 |
2010年 | 382篇 |
2009年 | 315篇 |
2008年 | 543篇 |
2007年 | 546篇 |
2006年 | 394篇 |
2005年 | 402篇 |
2004年 | 309篇 |
2003年 | 292篇 |
2002年 | 243篇 |
2001年 | 168篇 |
2000年 | 145篇 |
1999年 | 121篇 |
1998年 | 47篇 |
1997年 | 45篇 |
1996年 | 40篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 18篇 |
1992年 | 44篇 |
1991年 | 66篇 |
1990年 | 50篇 |
1989年 | 45篇 |
1988年 | 39篇 |
1987年 | 41篇 |
1986年 | 37篇 |
1985年 | 41篇 |
1984年 | 30篇 |
1983年 | 29篇 |
1982年 | 18篇 |
1981年 | 13篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 12篇 |
1973年 | 14篇 |
1970年 | 13篇 |
1968年 | 10篇 |
1966年 | 13篇 |
排序方式: 共有9362条查询结果,搜索用时 31 毫秒
81.
Câmara Vd Filhote MI Lima MI Alheira FV Martins MS Dantas TO Luiz RR 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(2):149-158
The main objective of this study was to promote the evaluation of an educational method to identify health risks among adolescents exposed to mercury by their work in gold mining production.The project was carried out with adolescents from a public school from the District of Monsenhor Horta, Municipality of Mariana, state of Minas Gerais. Statistical evaluation of the results revealed a significant increase in the amount of correct answers between the first and fifth stage concerning the definition of work accidents and its importance in relation to work-related diseases, accidents on route to and from the work place and violence at work site itself. 相似文献
82.
DR Brewster MJ Manary IS Menzies EV O'Loughlin RL Henry 《Archives of disease in childhood》1997,76(3):236-241
Intestinal permeability can be assessed non-invasively using the lactulose-rhamnose (L-R) test, which is a reliable measure of small intestinal integrity. AIMS: To determine risk factors for abnormal intestinal permeability in kwashiorkor, and to measure changes in L-R ratios with inpatient rehabilitation. DESIGN: A case-control study of 149 kwashiorkor cases and 45 hospital controls. The L-R test was adapted to study kwashiorkor in Malawi, with testing at weekly intervals during nutritional rehabilitation. Urine sugars were measured by thin layer chromatography in London. RESULTS: The initial geometric mean L-R ratios (x100) (with 95% confidence interval) in kwashiorkor were 17.3 (15.0 to 19.8) compared with 7.0 (5.6 to 8.7) for controls. Normal ratios are < 5, so the high ratios in controls indicate tropical enteropathy syndrome. Abnormal permeability in kwashiorkor was associated with death, oliguria, sepsis, diarrhoea, wasting and young age. Diarrhoea and death were associated with both decreased L-rhamnose absorption (diminished absorptive surface area) and increased lactulose permeation (impaired barrier function) whereas nutritional wasting affected only L-rhamnose absorption. Despite, clinical recovery, mean L-R ratios improved little on treatment, with mean weekly ratios of 16.3 (14.0 to 19.0), 13.3 (11.1 to 15.9) and 14.4 (11.0 to 18.8). CONCLUSION: Abnormal intestinal permeability in kwashiorkor correlates with disease severity, and improves only slowly with nutritional rehabilitation. 相似文献
83.
Teixeira AB Etchebehere CS Carvalho DC Sousa MC Santos AO Lima MC Ramos CD Camargo EE 《Clinical nuclear medicine》2000,25(6):484
A 47-year-old woman with adenocarcinoma of the right breast had bone scintigraphy with Tc-99m MDP. Bone imaging did not show any metastases. However, a large area of increased tracer uptake was seen extending from the abdomen to the pelvis. Abdominal ultrasound revealed a large solid and heterogeneous mass, measuring 18 x 11 x 14.3 cm, that originated in an empty uterus. A biopsy of the surgical specimen showed a leiomyoma of the uterus. 相似文献
84.
85.
A C L Nobre S M Nunes-Monteiro M C S A Monteiro A M C Martins A Havt P S F Barbosa A A M Lima H S A Monteiro 《Toxicon》2004,44(5):555-559
We showed previously that exposure to microcystin-LR causes renal toxic effects in isolated perfused rat kidney, and that inflammatory mediators from supernatants of macrophages stimulated by microcystin-LR are involved in this process. The aim of this research was to examine water and electrolytes secretion in vivo, induced by microcystin-LR and supernatant of macrophages stimulated for this toxin (SUP.MphiS + MCLR), using perfused rat ileal segment and ligated intestinal loop models. We found microcystin-LR at 1 microg/ml (0.09 +/- 0.003* vs. control 0.07 +/- 0.001 g of secretion/2 cm of loop; P < 0.05*) and the SUP.MphiS + MCLR after 18 h postinoculation (0.10 +/- 0.003 vs. control 0.03 +/- 0.002 g/cm) caused intestinal secretion. In addition, microcystin-LR caused significant sodium secretion (-2.18 +/- 0.72* vs. control 2.18 +/- 0.50 microEq g(-1) min(-1)), potassium (-0.26 +/- 0.04* vs. control 0.32 +/- 0.03 microEq g(-1) min(-1)), chloride (MCLR = -3.29 +/- 1.93* vs. control 0.88 +/- 1.25 microEq g(-1) min(-1)) and water (-0.012 +/- 0.004* vs. control 0.002 +/- 0.002 ml g(-1) min(-1)). We also demonstrated SUP.MphiS + MCLR to induce intestinal secretion of electrolytes (sodium, potassium, chloride) and water. These findings suggested that microcystin-LR and lamina propria macrophages-derived mediators are able to induce intestinal secretion in vivo, probably via inhibition of protein phosphatase. 相似文献
86.
87.
Genetic Analysis of PARK2 and PINK1 Genes in Brazilian Patients with Early-Onset Parkinson's Disease
Karla Cristina Vasconcelos Moura Mário Campos Junior Ana Lúcia Zuma de Rosso Denise Hack Nicaretta Jo?o Santos Pereira Delson José Silva Flávia Lima dos Santos Fabíola da Costa Rodrigues Cíntia Barros Santos-Rebou?as Márcia Mattos Gon?alves Pimentel 《Disease markers》2013,35(3):181-185
Parkinson''s disease is the second most frequent neurodegenerative disorder in the world, affecting 1-2% of individuals over the age of 65. The etiology of Parkinson''s disease is complex, with the involvement of gene-environment interactions. Although it is considered a disease of late manifestation, early-onset forms of parkinsonism contribute to 5–10% of all cases. In the present study, we screened mutations in coding regions of PARK2 and PINK1 genes in 136 unrelated Brazilian patients with early-onset Parkinson''s disease through automatic sequencing. We identified six missense variants in PARK2 gene: one known pathogenic mutation, two variants of uncertain role, and three nonpathogenic changes. No pathogenic mutation was identified in PINK1 gene, only benign polymorphisms. All putative pathogenic variants found in this study were in heterozygous state. Our data show that PARK2 point mutations are more common in Brazilian early-onset Parkinson''s disease patients (2.9%) than PINK1 missense variants (0%), corroborating other studies worldwide. 相似文献
88.
T.C.A. Ferrari M.A.P. Xavier P.V.T. Vidigal N.S. Amaral P.A. Diniz A.P. Resende D.M. Miranda A.C. Faria A.S. Lima L.C. Faria 《Brazilian journal of medical and biological research》2014,47(11):990-994
Estimates of occult hepatitis B virus (HBV) infection prevalence varies among
different studies depending on the prevalence of HBV infection in the study
population and on the sensitivity of the assay used to detect HBV DNA. We
investigated the prevalence of occult HBV infection in cirrhotic patients undergoing
liver transplantation in a Brazilian referral center. Frozen liver samples from 68
adults were analyzed using a nested polymerase chain reaction assay for HBV DNA. The
specificity of the amplified HBV sequences was confirmed by direct sequencing of the
amplicons. The patient population comprised 49 (72.1%) males and 19 (27.9%) females
with a median age of 53 years (range=18-67 years). Occult HBV infection was diagnosed
in three (4.4%) patients. The etiologies of the underlying chronic liver disease in
these cases were alcohol abuse, HBV infection, and cryptogenic cirrhosis. Two of the
patients with cryptic HBV infection also presented hepatocellular carcinoma. Markers
of previous HBV infection were available in two patients with occult HBV infection
and were negative in both. In conclusion, using a sensitive nested polymerase chain
reaction assay to detect HBV DNA in frozen liver tissue, we found a low prevalence of
occult HBV infection in cirrhotic patients undergoing liver transplant, probably due
to the low prevalence of HBV infection in our population. 相似文献
89.
90.
One‐year follow‐up of titanium/zirconium alloy X commercially pure titanium narrow‐diameter implants placed in the molar region of the mandible: a randomized controlled trial
下载免费PDF全文
![点击此处可从《Clinical oral implants research》网站下载免费的PDF全文](/ch/ext_images/free.gif)