全文获取类型
收费全文 | 12662篇 |
免费 | 1189篇 |
国内免费 | 577篇 |
专业分类
耳鼻咽喉 | 175篇 |
儿科学 | 531篇 |
妇产科学 | 138篇 |
基础医学 | 1321篇 |
口腔科学 | 40篇 |
临床医学 | 1065篇 |
内科学 | 2324篇 |
皮肤病学 | 42篇 |
神经病学 | 643篇 |
特种医学 | 304篇 |
外国民族医学 | 3篇 |
外科学 | 1503篇 |
综合类 | 2057篇 |
现状与发展 | 3篇 |
预防医学 | 897篇 |
眼科学 | 228篇 |
药学 | 1612篇 |
1篇 | |
中国医学 | 1106篇 |
肿瘤学 | 435篇 |
出版年
2024年 | 66篇 |
2023年 | 268篇 |
2022年 | 550篇 |
2021年 | 599篇 |
2020年 | 444篇 |
2019年 | 463篇 |
2018年 | 404篇 |
2017年 | 429篇 |
2016年 | 470篇 |
2015年 | 453篇 |
2014年 | 636篇 |
2013年 | 889篇 |
2012年 | 628篇 |
2011年 | 724篇 |
2010年 | 549篇 |
2009年 | 511篇 |
2008年 | 483篇 |
2007年 | 526篇 |
2006年 | 527篇 |
2005年 | 457篇 |
2004年 | 422篇 |
2003年 | 412篇 |
2002年 | 331篇 |
2001年 | 282篇 |
2000年 | 287篇 |
1999年 | 222篇 |
1998年 | 199篇 |
1997年 | 203篇 |
1996年 | 198篇 |
1995年 | 185篇 |
1994年 | 188篇 |
1993年 | 154篇 |
1992年 | 126篇 |
1991年 | 100篇 |
1990年 | 118篇 |
1989年 | 111篇 |
1988年 | 88篇 |
1987年 | 72篇 |
1986年 | 65篇 |
1985年 | 87篇 |
1984年 | 76篇 |
1983年 | 67篇 |
1982年 | 66篇 |
1981年 | 59篇 |
1980年 | 59篇 |
1979年 | 46篇 |
1978年 | 32篇 |
1977年 | 24篇 |
1976年 | 16篇 |
1971年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
3.
4.
5.
6.
BackgroundPercutaneous endoscopic gastrostomy (PEG) is required for Levodopa/Carbidopa Intestinal Gel (LCIG) delivery in patients with advanced Parkinson's disease (PD) as well as for enteral feeding in a variety of neurological disorders. Buried Bumper Syndrome (BBS) is a serious complication of PEG. The frequency of BBS in patients receiving LCIG treatment has never been reported.ObjectivesTo compare the frequency of BBS in patients on LCIG treatment or on enteral feeding over the past 12 years and identify possible risk factors.MethodsWe reviewed prospectively recorded data from 2009 to 2020 on two case-series: LCIG-treated PD patients and non-PD patients on enteral nutrition. We identified all BBS incidences. Patients’ characteristics, clinical manifestations, BBS management, possible risk factors and outcomes were analyzed.ResultsDuring the 12 years, 35 PD patients underwent PEG insertion for LCIG infusion, and 123 non-PD patients for nutritional support. There were eight cases of BBS in six PD patients (17.1%). Six of them were effectively managed without treatment discontinuation. Of the enteral feeding patients, only one developed BBS (0.8%) (p < 0.001). We identified inappropriate PEG site aftercare, weight gain, early onset PD, longer survival, treatment duration, dementia and PEG system design as potential risk factors for BBS development.ConclusionsBBS occurs more frequently in LCIG patients than in patients receiving enteral feeding. If detected early, it can be successfully managed, and serious sequalae or treatment discontinuation can be avoided. Regular endoscopic follow-up visits of LCIG-treated patients and increased awareness in patients and clinicians are recommended. 相似文献
7.
8.
Joseane Balan Da Silva Gleison Daion Piovezana Bossolani Camila Piva Greicy Brisa Malaquias Dias Jancarlo Gomes Ferreira Diogo Francisco Rossoni 《International journal of environmental health research》2016,26(5-6):578-588
The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services. 相似文献
9.
10.
Zi-Gang Che Ting Ni Zhen-Chang Wang De-Wang Wang 《World Journal of Clinical Cases》2021,9(8):1940-1945
BACKGROUNDNasolacrimal duct obstruction leading to epiphora is a common ophthalmologic complaint, and it may derive from amyloidosis in rare cases. There are a few reports about localized amyloidosis, and amyloidosis with involvement and obstruction of the nasolacrimal duct is exceedingly rare. CASE SUMMARYA 54-year-old male presented with a 2-year history of a lump overlying the left lacrimal sac that had grown rapidly for nearly half a year. Physical examination touched a firm lump in the left lacrimal sac. Nasal endoscopy discovered lesions in appearance of sediments with easy bleeding at the entry of the nasolacrimal duct of the left inferior nasal meatus. Computerized tomography scan revealed speckle high density in the left lacrimal sac and the dilated nasolacrimal duct. During an endoscopic exploration and excision, a large number of dacryoliths were exposed. Pathology indicated amorphous pink material and multinucleated giant cell reaction in the fibrous tissue.CONCLUSIONThis case showed amyloidosis in localized form mimicking dacryolith with nasolacrimal duct obstruction. In clinical practice, we should be aware of the possibility of localized amyloidosis in the nasolacrimal excretory system. 相似文献