全文获取类型
收费全文 | 11831篇 |
免费 | 637篇 |
国内免费 | 885篇 |
专业分类
耳鼻咽喉 | 129篇 |
儿科学 | 219篇 |
妇产科学 | 42篇 |
基础医学 | 595篇 |
口腔科学 | 82篇 |
临床医学 | 1514篇 |
内科学 | 2458篇 |
皮肤病学 | 24篇 |
神经病学 | 658篇 |
特种医学 | 653篇 |
外科学 | 2512篇 |
综合类 | 1785篇 |
现状与发展 | 1篇 |
预防医学 | 500篇 |
眼科学 | 130篇 |
药学 | 907篇 |
12篇 | |
中国医学 | 398篇 |
肿瘤学 | 734篇 |
出版年
2024年 | 27篇 |
2023年 | 247篇 |
2022年 | 442篇 |
2021年 | 599篇 |
2020年 | 527篇 |
2019年 | 359篇 |
2018年 | 353篇 |
2017年 | 345篇 |
2016年 | 444篇 |
2015年 | 401篇 |
2014年 | 987篇 |
2013年 | 918篇 |
2012年 | 835篇 |
2011年 | 893篇 |
2010年 | 665篇 |
2009年 | 631篇 |
2008年 | 670篇 |
2007年 | 674篇 |
2006年 | 542篇 |
2005年 | 457篇 |
2004年 | 323篇 |
2003年 | 276篇 |
2002年 | 209篇 |
2001年 | 190篇 |
2000年 | 158篇 |
1999年 | 136篇 |
1998年 | 121篇 |
1997年 | 108篇 |
1996年 | 75篇 |
1995年 | 73篇 |
1994年 | 66篇 |
1993年 | 61篇 |
1992年 | 54篇 |
1991年 | 47篇 |
1990年 | 56篇 |
1989年 | 47篇 |
1988年 | 37篇 |
1987年 | 21篇 |
1986年 | 34篇 |
1985年 | 35篇 |
1984年 | 29篇 |
1983年 | 11篇 |
1982年 | 42篇 |
1981年 | 31篇 |
1980年 | 17篇 |
1979年 | 18篇 |
1978年 | 21篇 |
1977年 | 18篇 |
1976年 | 8篇 |
1973年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
目的描述12~36月龄幼儿胃肠道功能情况,探讨潜在影响因素。方法2018年9月—2019年1月在北京市朝阳区某社区卫生服务中心招募12~36月龄幼儿385名,收集幼儿及母亲基本信息,采用简版《婴幼儿胃肠道症状问卷》评估幼儿胃肠道功能。问卷共10个问题,反映幼儿胃肠道症状(6个问题)和相关行为(4个问题)。胃肠道功能总评分为10~60分,其中胃肠道症状6~36分、胃肠道相关行为4~24分,评分越高提示胃肠功能越弱;将总评分等于或高于第二个三分位数(17分)定义为轻度胃肠不适。采用多因素logistic回归分析幼儿轻度胃肠不适的可能影响因素。结果幼儿胃肠道功能总评分、症状评分和相关行为评分的中位数(四分位数间距)分别为13.0(11.0~19.0)分、6.0(6.0~10.0)分和6.0(5.0~8.0)分。小月龄(12~17月龄14.5分,18~23月龄13.0分)比大月龄(24~29月龄12.0分,30~36月龄12.5分)、母亲为初产妇(14.0分)比经产妇(12.0分)的幼儿中位胃肠道功能总评分高(P<0.05)。轻度胃肠不适幼儿124名(32.2%),母亲为初产妇(36.8%)比母亲为经产妇(21.8%)的幼儿轻度胃肠不适发生率显著升高(P=0.004)。多因素logistic回归分析显示,12~17月龄幼儿与30~36月龄幼儿相比(调整OR,2.32;95%CI,1.14~4.71)、母亲为初产妇的幼儿与经产妇的幼儿相比(调整OR,2.05;95%CI,1.19~3.52),轻度胃肠不适风险显著升高。幼儿性别、分娩方式、母乳喂养时长和母亲分娩年龄对轻度胃肠不适发生风险无显著影响。结论幼儿胃肠道功能整体较好,幼儿月龄及母亲产次影响幼儿胃肠功能,小月龄及母亲为初产妇的幼儿易发生轻度胃肠不适。 相似文献
72.
选择性动脉造影在不明原因的下消化道出血诊断中的价值探讨 总被引:1,自引:0,他引:1
目的 探讨选择性动脉造影和造影时机选择在不时原因下消化道出血诊断中的价值。方法 运用Seldinger技术对32例患者进行选择性肠系膜上、下动脉及其分支造影,其中少量出血患者17例,中至大量15例。首次出血3例,2次以上反复出血29例。结果 32例中28例发现病变(87.5%),其中肿瘤性病变(n=15)非肿瘤性病变(n=13),少理出血未见造影剂外溢征,中至大量出血中造影剂外溢征占33%。结论 选择性动脉造影检查下消化道出血是一种安全、有效的方法,在少量出血和出血间歇期仍有很大价值;造影显示病变部位更重要于显示出血征象。 相似文献
73.
目的:观察健脾祛湿方对脾虚湿盛型高脂血症大鼠血脂、胃肠功能、水液代谢的影响及作用机制。方法:将56只SD大鼠随机分为空白组(n=8)和造模组(n=48),采用“劳倦过度+饮食不节+高脂饲料喂养”复制脾虚湿盛型高脂血症大鼠模型。造模4周后,根据总胆固醇(TC)水平将造模组随机分成6组:即模型组,血脂康组,参苓白术颗粒组,健脾祛湿方低、中、高剂量组,每组8只。分组后开始给药,灌胃剂量为1 mL/100 g,空白组、模型组给予生理盐水,其余组给予相应的受试物,连续给药6周。测定血脂四项TC、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-Ch)和高密度脂蛋白胆固醇(HDL-Ch),胃肠激素,即胃动素(MTL)、促胃液素(GAS)和血管活性肠肽(VIP),水液调节激素醛固酮(ALD)、抗利尿激素(ADH)和心房利尿钠肽(ANP),以及白蛋白(ALB)和总蛋白(TP),采用苏木精-伊红(HE)染色法观察胃、结肠组织形态,免疫荧光法检测结肠水孔蛋白(AQP)3、胃AQP4的表达位置及水平,采用蛋白质印迹法(Western Blotting)检测结肠、胃组织中闭合蛋白(Occludin)的表达量。结果:与正常组比较,模型组大鼠血清TC、TG、LDL-Ch水平升高(P<0.001),HDL-Ch水平降低(P<0.05),血清MTL、GAS水平降低(P<0.001,P<0.01),VIP升高(P<0.001),ALD、ADH升高(P<0.05,P<0.001),ANP水平显著降低(P<0.001),TP、ALB水平降低(P<0.001,P<0.05)。结肠绒毛、胃黏膜出现大量脱落情况,结肠AQP3荧光强度降低,胃AQP4荧光表达增强,结肠、胃组织Occludin表达水平降低。与模型组比较,血脂康组、参苓白术颗粒组、健脾祛湿方低、中、高剂量组大鼠血清TC、TG、LDL-Ch水平呈下降趋势,HDL-C水平升高,MTL、GAS显著升高,VIP水平显著降低,ALD、ADH水平降低,ANP显著升高,结肠、胃组织形态结构有所改善。结肠AQP3荧光表达增强,胃AQP4荧光强度减弱,结肠、胃组织Occludin表达水平增强。结论:健脾祛湿方可降低脾虚湿盛型高脂血症大鼠血脂,有健脾祛湿之功,其作用机制可能是通过调节Occludin、AQP3、AQP4的表达,保护紧密连接结构的完整性达到促进胃肠消化吸收功能,改善水液代谢障碍的作用。 相似文献
74.
《European journal of medical genetics》2023,66(2):104678
BackgroundSubjects with Megalencephaly-Capillary Malformation-Polymicrogyria syndrome (MCAP) can present with a Chiari Malformation Type 1 and resulting alterations in cerebrospinal fluid (CSF) dynamics, which may require surgical treatment. The aim of this paper is to describe the features of children with MCAP who underwent surgical decompression for CM1, and to explore the PIK3CA variant allele frequency (VAF) identified in cerebellar parenchyma and other adjacent structures.MethodsThis study reviewed two cases of children with CM1 and MCAP who underwent surgical decompression treatment. These two cases were part of a national cohort of 12 MCAP patients who had CM1, due to their surgical eligibility. Tissue samples were obtained from the cerebellar tonsils and adjacent anatomical structures during the surgical procedures. Samples were then subsequently analyzed for PIK3CA postzygotic variants.ResultsIn both cases, alterations in CSF dynamics, specifically hydrocephalus and syringomyelia, were observed and required surgical treatment. PIK3CA targeted sequencing determined the VAF of the postzygotic variant in both cerebellar and adjacent bone/connective tissues.DiscussionThe recognition of a CM1 comorbidity in MCAP patients is of paramount importance when considering personalized treatment options, especially because these patients are at higher risk of developing complications during surgical decompression surgery. The variable PIK3CA VAF identified in the different analyzed tissues might help explain the heterogeneous nature and severity of anomalies observed in the volume of the posterior fossa structures in MCAP patients and associated CSF and venous disorders. 相似文献
75.
《Surgery for obesity and related diseases》2021,17(12):2054-2064
BackgroundSleeve gastrectomy (SG) is widely applied. Few studies have evaluated patient-reported abdominal symptoms after SG.ObjectiveTo evaluate the prevalence of chronic abdominal pain (CAP) and symptom characteristics after SG.SettingOslo University Hospital and Voss Hospital.MethodsWe performed a longitudinal prospective cohort study of patients operated on with SG at two tertiary referral centers. For broad assessments of abdominal pain and symptoms, consultations were performed and questionnaires retrieved before and 2 years after SG. The definition of CAP or recurrent abdominal pain lasting for more than 3 months was sustained. Preoperative predictors of CAP were explored.ResultsOf 249 patients at baseline, 207 (83.1%) had follow-up consultations. Mean preoperative body mass index was 43.9 (6.0) kg/m2, and 181 patients (72.7%) were female. Total weight loss was 31.9% (10.4%). CAP was reported in 32 of 223 patients (14.3%) before and in 50 of 186 patients (26.9%) after SG (P =.002). All mean gastrointestinal symptoms rating scale questionnaire scores increased after SG, and they were higher in patients with CAP. Symptoms of depression decreased but were more prevalent in patients with CAP at follow-up. Most quality-of-life scores increased after SG. However, patients with CAP had lower scores (except for physical functioning). Preoperative bothersome Gastrointestinal Symptom Rating Scale reflux symptoms, study center, and younger age seemed to predict CAP after SG.ConclusionThe prevalence of patient-reported CAP increased after SG. Patients reporting CAP had reduced quality-of-life scores. 相似文献
76.
77.
78.
Pil Whan Yoon Jong Yeal Kang Chul-Ho Kim Soong Joon Lee Jeong Joon Yoo Hee Joong Kim Sung Keun Kang Ju Hyeon Min Kang Sup Yoon 《Clinics in Orthopedic Surgery》2021,13(1):37
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events. 相似文献
79.
IntroductionThe effectiveness of transanal decompression tube (TDT) to prevent anastomotic leakage after rectal surgery has been widely accepted in recent years. However, a rare complication of intestinal perforation due to TDT has been also reported.Presentation of caseA 88-year-old woman underwent laparoscopic low anterior resection for rectal cancer. An abdominal drainage tube adjacent to the colorectal anastomosis and a TDT were placed. The patient experienced abdominal pain, nausea and elevated inflammatory markers on postoperative day 6. Enema and computed tomography demonstrated colonic perforation due to the TDT, and emergency laparotomy was performed. Perforation of the anterior sigmoid colon located at the proximal side of the colorectal anastomosis was seen, and the TDT was exposed to the abdominal cavity. Therefore, primary closure of the perforation site, peritoneal lavage, drainage tube placement and transverse colostomy was performed.DiscussionIn our case, TDT seemed to compress the anterior wall of the colon and lead to perforation. The looseness of the remaining oral intestinal tract depressed in the pelvis was compressed by the TDT.ConclusionTDTs should be very carefully placed to avoid complication. The length and looseness of the oral intestine and the relationship between the TDT to be inserted might be important. 相似文献
80.