首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2371篇
  免费   166篇
  国内免费   116篇
耳鼻咽喉   59篇
儿科学   82篇
妇产科学   4篇
基础医学   206篇
口腔科学   12篇
临床医学   160篇
内科学   912篇
皮肤病学   23篇
神经病学   53篇
特种医学   98篇
外科学   147篇
综合类   361篇
预防医学   45篇
眼科学   5篇
药学   194篇
中国医学   192篇
肿瘤学   100篇
  2024年   2篇
  2023年   41篇
  2022年   76篇
  2021年   92篇
  2020年   92篇
  2019年   95篇
  2018年   106篇
  2017年   82篇
  2016年   106篇
  2015年   85篇
  2014年   189篇
  2013年   177篇
  2012年   160篇
  2011年   137篇
  2010年   131篇
  2009年   117篇
  2008年   100篇
  2007年   124篇
  2006年   113篇
  2005年   92篇
  2004年   74篇
  2003年   60篇
  2002年   44篇
  2001年   58篇
  2000年   32篇
  1999年   35篇
  1998年   21篇
  1997年   17篇
  1996年   22篇
  1995年   15篇
  1994年   26篇
  1993年   15篇
  1992年   19篇
  1991年   18篇
  1990年   15篇
  1989年   7篇
  1988年   11篇
  1987年   2篇
  1986年   9篇
  1985年   7篇
  1984年   3篇
  1982年   2篇
  1981年   5篇
  1979年   6篇
  1978年   3篇
  1977年   3篇
  1976年   2篇
  1973年   1篇
  1970年   1篇
  1968年   1篇
排序方式: 共有2653条查询结果,搜索用时 515 毫秒
1.
习洋  陶泽璋 《疑难病杂志》2020,(2):207-211,216
慢性鼻窦炎(CRS)是一种常见的慢性非特异感染性鼻部疾病,病理分型主要分为Th2细胞介导的嗜酸性粒细胞性鼻窦炎(ECRS)和Th1细胞介导的非嗜酸性粒细胞性鼻窦炎(非ECRS)2种表型。欧洲国家CRS患病人群主要表现为ECRS,而随着亚洲国家的急剧工业化发展,其ECRS的比例也在急剧增加。ECRS发病机制复杂,涉及多种免疫细胞和相关因子相互作用。其治疗方法包括抗生素、激素药物治疗及手术治疗等,但仍有部分患者症状难以改善或存在复发的风险。Ⅱ型固有淋巴样细胞(ILC2s)是一种非B、非T的新型淋巴细胞,与Th2免疫应答关系密切。文章就ILC2s在ECRS发病机制中的作用进行综述,以期为ECRS的诊断和治疗提供理论参考。  相似文献   
2.
目的:观察降气化痰理血法治疗食管重建术后全食管炎的疗效.方法:降气化痰理血法治疗食管重建术后食管炎62例(治疗组),并与西药治疗56例(对照组)作对照.结果:两组疗效比较差异有显著性意义(P<0.05),治疗组总有效率87.1%;治疗组临床主要症状改善明显;纤维内镜显示食管粘膜炎性改善,两组Ⅱ期、Ⅲ期比较差异都具有显著性意义(P<0.05).结论:降气化痰理血中药具有缓解和消除临床症状,改善食管粘膜炎性状况,具有抗炎,抗胃肠反流和提高机体术后恢复能力.  相似文献   
3.
Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10–18, 10–16, 10–14M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment.  相似文献   
4.
If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH<4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH<4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean ±2sd of the relative differences between the two test results for all 53 subjects. Total percent time with pH<4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.Supported, in part, by Public Health Services Grant AM 34200-01A1 from NIADDIK.  相似文献   
5.
目的探讨骨嗜酸细胞肉芽肿的临床表现、诊断和治疗效果。方法1991年3月至2006年3月收治骨嗜酸细胞肉芽肿28例,男19例,女9例;年龄1-61岁,平均22.4岁。病程20d~10个月。单发24例,多发4例。影像学表现为溶骨性改变,15例伴软组织肿物影。于外院确诊5例,入院后误诊为原发肿瘤及转移癌12例。所有病例均经病理学确诊。单发病例行化疗1例,手术治疗20例,手术后辅以放疗、化疗、激素综合治疗3例;多发病例采用放疗1例,激素治疗1例,综合治疗2例。结果全部病例随访7个月 ̄15年,平均5.3年。20例手术者手术治愈率100%;术后辅以放疗、化疗及激素治疗者无复发;植骨者6~12个月骨性愈合,随访功能不受限。1例行胸椎椎板减压术者截瘫部分恢复。4例多发病例中2例出现复发,再次给予激素及放疗、化疗后缓解。结论骨嗜酸细胞肉芽肿临床症状及影像学表现与肿瘤类似,误诊率极高。术前应尽可能行穿刺活检。对单发病例宜采用手术治疗,可辅以放疗或化疗;多发病例病灶多、范围广,不宜采用手术治疗,可选择放疗、化疗、激素治疗等综合疗法。  相似文献   
6.
Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa.  相似文献   
7.
8.
Summary The authors have studied the pancreas of a premature female infant born to a diabetic mother. The findings included a peri-insular eosinophilic leucocyte infiltration, macropolinesia and a marked increase in B cells. In the exocrime parenchyma small B cells aggregates were also observed. B cells contained voluminous hypercromatic muclei and degranulated cytoplasm. Morphometric data demonstrated an increase in islet tissue. These morphological findings are indicative of excessive insulin secretion. The presence of eosinophilic leucocytes in pancreatic tissue and the pathogenic mechanism involved are discussed.  相似文献   
9.
目的:探究疏肝和胃降逆汤加减联合雷贝拉唑治疗肝胃不和证反流性食管炎(RE)患者的临床疗效。方法:选取莆田市涵江区中医院2021年2月至2022年2月期间收治的100例肝胃不和证RE患者,随机分为对照组与观察组,各50例。对照组患者采用雷贝拉唑、莫沙必利治疗,观察组患者采用疏肝和胃降逆汤加减联合雷贝拉唑治疗。比较两组患者的临床疗效、中医证候积分、血清相关指标及6个月复发率。结果:观察组患者治疗总有效率为94.00%,高于对照组的76.00%,差异具有统计学意义(P <0.05)。治疗后观察组患者各项中医证候积分低于对照组,差异具有统计学意义(P <0.05)。治疗后观察组患者血清胃动素(MTL)、胃泌素(GAS)水平高于对照组,生长抑素(SS)水平低于对照组,差异具有统计学意义(P <0.05)。治疗后观察组患者血清白细胞介素–1β(IL–1β)、IL–2、瘦素(Leptin)、降钙素基因相关肽(CGRP)水平低于对照组,差异具有统计学意义(P <0.05)。随访6个月,观察组失访4例,对照组失访3例。观察组患者6个月复发率为2.13%,低于对照组的18.42%,...  相似文献   
10.
Fibroinflammatory lesions of the sinonasal tract are one of the most common head and neck lesions submitted to surgical pathology. When the fibroinflammatory pattern represents the lesion (i.e., not surface reactive ulceration), an algorithmic approach can be useful. Separated into reactive, infectious, and neoplastic, and then further divided based on common to rare, this logical progression through a series of differential considerations allows for many of these lesions to be correctly diagnosed. The reactive lesions include chronic rhinosinusitis and polyps, granulomatosis with polyangiitis, and eosinophilic angiocentric fibrosis. Infectious etiologies include acute invasive fungal rhinosinusitis, rhinoscleroma, and mycobacterial infections. The neoplastic category includes lobular capillary hemangioma, inflammatory myofibroblastic tumor, and NK/T-cell lymphoma, nasal type. Utilizing patterns of growth, dominant cell types, and additional histologic features, selected ancillary studies help to confirm the diagnosis, guiding further clinical management.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号