全文获取类型
收费全文 | 188563篇 |
免费 | 1623篇 |
国内免费 | 60篇 |
专业分类
耳鼻咽喉 | 1406篇 |
儿科学 | 6986篇 |
妇产科学 | 3447篇 |
基础医学 | 18322篇 |
口腔科学 | 2623篇 |
临床医学 | 13108篇 |
内科学 | 33689篇 |
皮肤病学 | 1168篇 |
神经病学 | 17585篇 |
特种医学 | 9268篇 |
外科学 | 30818篇 |
综合类 | 2359篇 |
一般理论 | 3篇 |
预防医学 | 18906篇 |
眼科学 | 2908篇 |
药学 | 10089篇 |
中国医学 | 700篇 |
肿瘤学 | 16861篇 |
出版年
2023年 | 112篇 |
2022年 | 317篇 |
2021年 | 515篇 |
2020年 | 357篇 |
2019年 | 431篇 |
2018年 | 22346篇 |
2017年 | 17652篇 |
2016年 | 19800篇 |
2015年 | 1345篇 |
2014年 | 1412篇 |
2013年 | 1462篇 |
2012年 | 7999篇 |
2011年 | 22079篇 |
2010年 | 19443篇 |
2009年 | 12060篇 |
2008年 | 20407篇 |
2007年 | 22555篇 |
2006年 | 1430篇 |
2005年 | 3027篇 |
2004年 | 4014篇 |
2003年 | 4903篇 |
2002年 | 2992篇 |
2001年 | 327篇 |
2000年 | 448篇 |
1999年 | 234篇 |
1998年 | 291篇 |
1997年 | 304篇 |
1996年 | 164篇 |
1995年 | 180篇 |
1994年 | 150篇 |
1993年 | 116篇 |
1992年 | 67篇 |
1991年 | 117篇 |
1990年 | 148篇 |
1989年 | 91篇 |
1988年 | 79篇 |
1987年 | 57篇 |
1986年 | 40篇 |
1985年 | 39篇 |
1984年 | 40篇 |
1983年 | 39篇 |
1982年 | 44篇 |
1980年 | 52篇 |
1974年 | 29篇 |
1938年 | 61篇 |
1937年 | 25篇 |
1935年 | 22篇 |
1934年 | 30篇 |
1932年 | 56篇 |
1930年 | 48篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
71.
Late-onset and Recurrent Neonatal Group B Streptococcal Disease Associated with Breast-milk Transmission 总被引:2,自引:0,他引:2
Michael Kotiw Gwang W. Zhang Grant Daggard Elizabeth Reiss-Levy John W. Tapsall Andrew Numa 《Pediatric and developmental pathology》2003,6(3):251-256
The purpose of the study was to determine the epidemiological relationships in three unrelated cases of neonatal late-onset Group B streptococcal (GBS) disease and maternal breast-milk infection with GBS. All deliveries were by cesarean section; case 1 was at term, and cases 2 and 3 were at 32- and 33-wk gestation, respectively. Case 1 relates to a mother with clinical mastitis and recurrent GBS infection in a 20-day-old male infant. Following antibiotic therapy and cessation of breast-feeding, the infant recovered without sequelae. Case 2 refers to a mother with clinical mastitis and the occurrence of late-onset GBS disease in 5-wk-old male twins. Despite intervention, one infant died and the second became ill. Following antibiotic therapy and cessation of breast-feeding, the surviving infant recovered without sequelae. Case 3 refers to a mother with sub-clinical mastitis and late-onset GBS infection occurring in a 6-day-old female twin. Following intervention, the infant recovered but suffered a bilateral thalamic infarction resulting in developmental delay and a severe seizure disorder. Following recovery of GBS from an inapparent mastitis and cessation of breast-feeding, the second infant remained well. Blood cultures from all affected infants and maternal breast milk were positive for GBS. Epidemiological relationships between neonatal- and maternal-derived GBS isolates were confirmed by a random amplified polymorphic DNA polymerase chain reaction assay (RAPD-PCR). This study is significant in that it has demonstrated that maternal milk (in cases of either clinical or sub-clinical mastitis) can be a potential source of infection resulting in either late-onset or recurrent neonatal GBS disease. 相似文献
72.
Ona Faye-Petersen 《Pediatric and developmental pathology》2003,6(6):599-600
73.
Recent reports of sexually transmitted infection-rate increases among men indicate the need for renewed study of male sexual risk behavior to aid development of updated and novel risk reduction interventions. Men who have childhood sexual abuse (CSA) histories consistently report frequent sexual risk behavior. The objective of this sturdy is to explore whether posttraumatic stress disorder (PTSD) and depression are moderators and/or mediators of the association between CSA and sexual risk in adult men. A cross-sectional survey study employing random digit dial recruitment was administered to men aged 18–49 years from Philadelphia County. Two bundred ninety eight men were recruited and screened for CSA history, administered items from the Posttraumatic Stress Diagnostic Scale (PDS) and Center for Epidemiologic Studies—Depression (CES-D), and asked to estimate their number of lifetime sexual partners (LSPs). Effects of sociodemographic characteristics, CSA, PTSD, and depression on the number of LSPs were modeled using Poisson regression. Results show that 197 (66%) men participated; 43 (22%) had CSA histories. CSA was significantly associated with PTSD/depression (P=.03). Four sociodemographic variables (age, race, sexual identity, and education), CSA (incidence rate ratio, IRR=1.47, P<.001), PTSD (IRR=1.19, P=.04), depression (IRR=1.29, P=.001), all 2-way interactions, and the 3-way CSA/PTSD/depression interaction (IRR=11.00, P<.001) were associated with the number of LSPs (R2=0.27). In conclusion, sexual partnership patterns unique to men with CSA histories and comorbid PTSD/depression appear to lead to substantially higher numbers of LSPs. Estimates of this relationship may have been biased toward the null by underreporting that can occur with phone surveys. Cross-sectional studies do not support causal inferences; however, the identification of a moderating and mediating influence of PTSD/depression on the relationship between CSA and sexual risk behavior is important and suggests the need for future studies with larger samples that examine trajectories for CSA, psychiatric illness, and sexual partnerships. 相似文献
74.
Ricardo Mitrani Momo Vasilic August Bruguera 《Practical procedures & aesthetic dentistry》2005,17(1):71-8; quiz 80
Recent scientific and technological developments have allowed the dental team to execute revolutionary restorative treatments that would have once been considered unfeasible. This article describes a restorative alternative for fixed implant-supported reconstructions, consisting of a CAD/CAM-generated framework and CAD/CAM-generated all-ceramic cement-retained restorations. Distinct advantages of this type of restoration include the passive fit of the framework, the ability of the ceramist to fabricate individual restorations independent from the framework, and the delivery of optimal aesthetics. 相似文献
75.
Doris Cerecedo Sirenia González Mónica Mondragón Elba Reyes Ricardo Mondragón 《Blood coagulation & fibrinolysis》2006,17(2):161-164
Platelets are cell fragments with dynamic properties involved in clot formation after tissue damage. Platelet activation causes a change in shape, secretion of intracellular granules and aggregation with each other through the cytoskeleton components and biochemical changes. Platelet adhesion, considered as the major event in haemostasis, has been studied in several in-vitro and in-vivo models to evaluate the feasible thrombogenicity of some materials, the dynamics of specific receptors, as well as the effect of different buffers and inhibitors in this process. In spite of the numerous reports about platelet activation, to date there is no information available about the fine structure of the platelet-platelet and platelet-substrate interactions. In the present report we describe an in-vitro system that allows the visualization of these interactions: platelets are adhered to an inert substrate, and interactions with suspended platelets as a process to initiate the formation of thrombi was followed by ultramicrotomy and transmission electron microscopy. 相似文献
76.
77.
78.
79.
Péter Móricz Imre Gerlinger Jenő Solt Krisztina Somogyvári József Pytel 《European archives of oto-rhino-laryngology》2007,264(12):1441-1445
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy
and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic
balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases.
In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The
average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature
data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every
effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major
myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap
needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free
flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in
prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and
neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter
dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure
provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However,
a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion
of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications. 相似文献
80.
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