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   932篇
  免费   54篇
  国内免费   57篇
耳鼻咽喉   1篇
儿科学   38篇
妇产科学   37篇
基础医学   149篇
口腔科学   83篇
临床医学   42篇
内科学   169篇
皮肤病学   14篇
神经病学   7篇
特种医学   7篇
外科学   37篇
综合类   101篇
预防医学   209篇
眼科学   1篇
药学   116篇
  1篇
中国医学   15篇
肿瘤学   16篇
  2024年   2篇
  2023年   13篇
  2022年   36篇
  2021年   68篇
  2020年   54篇
  2019年   33篇
  2018年   30篇
  2017年   34篇
  2016年   48篇
  2015年   37篇
  2014年   62篇
  2013年   112篇
  2012年   62篇
  2011年   63篇
  2010年   54篇
  2009年   48篇
  2008年   54篇
  2007年   45篇
  2006年   36篇
  2005年   36篇
  2004年   19篇
  2003年   16篇
  2002年   25篇
  2001年   3篇
  2000年   2篇
  1999年   15篇
  1998年   5篇
  1997年   4篇
  1996年   2篇
  1995年   1篇
  1994年   3篇
  1993年   4篇
  1992年   2篇
  1991年   4篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1985年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1974年   1篇
  1973年   1篇
排序方式: 共有1043条查询结果,搜索用时 15 毫秒
41.
宫颈疾病包括宫颈炎症、宫颈鳞状上皮内病变及宫颈癌,近年研究发现阴道微生物菌群产生的细胞因子及局部免疫系统与宫颈疾病的发生、发展有关。正常女性的阴道微生态环境由多种微生物构成,其中乳杆菌对维持阴道微生态平衡发挥着重要作用。宫颈癌在女性恶性肿瘤中发生率位居第一,其发生与人乳头瘤病毒(HPV)持续感染密切相关,但并非所有感染HPV者均患宫颈癌,其病因为多因素综合作用。因乳杆菌变化导致的阴道疾病与HPV感染相互作用,共同参与宫颈疾病的发生、进展,系统有效的阴道微生态环境检测对及时调节阴道微生态平衡非常重要。阴道微生物菌群与宫颈疾病之间的关系成为许多学者的研究热点,综述阴道微生态与宫颈疾病发生、发展的相关性,为宫颈疾病尤其是宫颈癌的预防、治疗及预后提供理论依据。  相似文献   
42.
肠易激综合征(irritable bowel syndrome,IBS)是临床上常见的功能性胃肠病,其会影响患者的生活质量.因此探寻IBS的有效治疗方法具有重要意义.益生菌可改善IBS患者的症状并提高其生活质量,其中备受关注的是鼠李糖乳杆菌(Lactobacillus rhamnosus GG,LGG).LGG是目前被...  相似文献   
43.
目的:观察热致死的发酵乳杆菌对牛乳β-乳球蛋白(BLG)致敏小鼠Th1/Th2细胞平衡、血清抗体水平及T细胞亚群数量的影响,探讨其缓解过敏反应的作用。方法:用牛乳BLG和弗氏佐剂的混合液腹腔注射诱发BALB/c小鼠致敏,建立动物过敏模型。将实验动物随机分为空白组、致敏组和不同剂量的热致死发酵乳杆菌组。采用ELISA法测定各组小鼠血清总IgE、BLG特异性IgE和总IgG含量。体外分离培养各组小鼠脾细胞,采用ELISA法检测细胞上清液中Th1型细胞因子(IL-12、IFN-γ)和Th2型细胞因子(IL-4)水平,采用流式细胞术检测脾淋巴细胞中CD3+、CD4+和CD8+T百分含量。结果:发酵乳杆菌组小鼠脾细胞培养上清液中IFN-γ/IL-4比值为13.53,显著高于致敏组的3.34(P<0.05);血清总IgE、BLG特异性IgE和总IgG水平显著降低(P<0.05);脾细胞中CD3+和CD4+T细胞比例升高,CD4+/CD8+比值趋近正常组。特别是高剂量的热致死发酵乳杆菌组小鼠脾细胞培养上清液中抑制IL-4分泌的效果显著优于致敏组(P>0.05),且该组小鼠血清的抗体水平和CD4+/CD8+比值与空白组相比无差异(P>0.05)。结论:热致死的发酵乳杆菌干预可改善小鼠的BLG过敏症状,其作用可能与促进Th1占优势的Th1/Th2细胞平衡,阻断IgE、IgG分泌及平衡T细胞亚群数量相关。  相似文献   
44.
谢迎新 《医学信息》2020,(2):138-139,146
目的 观察复方嗜酸乳杆菌联合常规四联疗法治疗幽门螺旋杆菌(Hp)感染消化性溃疡的疗效。方法 选择2018年5月~2019年5月在我院诊治的幽门螺旋杆菌感染消化性溃疡患者112例,采用随机数字表法分为对照组和观察组,各56例。对照组采用常规四联疗法治疗,观察组在对照组基础上加用复方嗜酸乳杆菌治疗,比较两组临床治疗总有效率、临床症状(反酸、上腹痛、饱胀、呕吐)评分、Hp根除率以及临床不良反应发生情况。结果 观察组治疗总有效率为94.64%,高于对照组的80.35%,差异有统计学意义(P<0.05);观察组反酸、上腹痛、饱胀、呕吐症状评分均低于对照组,差异有统计学意义(P<0.05);观察组Hp根除率为92.85%,高于对照组的78.57%,差异有统计学意义(P<0.05);观察组不良反应发生率为3.57%,低于对照组的16.07%,差异有统计学意义(P<0.05)。结论 复方嗜酸乳杆菌联合常规四联疗法治疗Hp感染消化性溃疡疗效确切,可促进Hp根除,有助于减轻临床症状,降低临床症状评分,且临床不良反应少。  相似文献   
45.
46.
Traditional medical treatments for ulcerative colitis (UC) are still compromised by its adverse effects and not potent enough to keep in remission for long-term periods. So, new therapies that are targeted at specific disease mechanisms have the potential to provide more effective and safe treatments for ulcerative colitis. Probiotics is recently introduced as a therapy for ulcerative colitis. In the present study, Lactobacillus acidophilus was selected as a probiotic therapy to investigate its effects in oxazolone-induced colitis model in rats that mimics the picture in human. The rats were grouped (8 rats each) as normal control group (Group I), Group II served as untreated oxazolone-induced colitis, Group III oxazolone-induced colitis treated with probiotic L. acidophilus (1 × 107 colony-forming units (CFU)/mL/day oral for 14 days), Group IV oxazolone-induced colitis treated with olsalazine (60 mg/kg/day oral for 14 days), Group V oxazolone-induced colitis treated with probiotic L. acidophilus and olsalazine in the same doses and duration. Disease activity index (DAI) was recorded, serum levels of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and intrleukin-6 (IL-6) was assessed as inflammatory markers and the histopathological picture of the colon of each rat was studied. Disease activity index (DAI) showed significant positive correlation with the elevated serum levels of CRP (r = 0.741, p < 0.05), TNF-α (r = 0.802, p < 0.05) and IL-6 (r = 0.801, p < 0.05). Treatment with either L. acidophilus (group III) or olsalazine (group IV) resulted in significant reduction in serum levels of CRP, TNF-α and IL-6, as well as disease activity index (DAI). Treatment with combination of L. acidophilus and olsalazine (group V) offered more significant reduction in serum levels of CRP, TNF-α, IL-6 and disease activity index (DAI) when compared to either group II (untreated group), group III (treated with L. acidophilus) or group IV (treated with olsalazine). So, it was concluded that L. acidophilus probiotic could be recommended as adjuvant therapy in combination with olsalazine to achieve more effective treatment for ulcerative colitis. For application in human, this needs to be verified in further clinical studies.  相似文献   
47.
Background: Probiotics are living microorganisms that provide beneficial effects for the host when administered in proper quantities. The aim of this double‐masked placebo‐controlled parallel‐arm randomized clinical trial is to evaluate the clinical effects of a Lactobacillus rhamnosus SP1‐containing probiotic sachet as an adjunct to non‐surgical therapy. Methods: Twenty‐eight systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically at baseline and 3, 6, 9, and 12 months after therapy. Clinical parameters measured included plaque accumulation, bleeding on probing, probing depths (PDs), and clinical attachment loss. Patients received non‐surgical therapy, including scaling and root planing (SRP), and were assigned randomly to a test (SRP + probiotic, n = 14) or control (SRP + placebo, n = 14) group. The intake, once a day for 3 months, of an L. rhamnosus SP1 probiotic sachet commenced after the last session of SRP. Results: Both test and control groups showed improvements in clinical parameters at all time points evaluated. However, the test group showed greater reductions in PD than the control. Also, at initial visits and after 1‐year follow‐up, the test group showed a statistically significant reduction in the number of participants with PD ≥6 mm, indicating a reduced need for surgery, in contrast to the placebo group. Conclusion: The results of this trial indicate that oral administration of L. rhamnosus SP1 resulted in similar clinical improvements compared with SRP alone.  相似文献   
48.
乳杆菌是大多数健康女性阴道微生态中的优势菌群,对预防泌尿生殖系统感染性疾病起重要作用。能产生乳酸、过氧化氢、细菌素和生物表面活性物质等抑菌物质是乳杆菌成为潜在益生菌的重要基础。本文对阴道来源的乳杆菌抑菌物质相关研究进展作一综述。  相似文献   
49.
The purpose of this work was to investigate whether a probiotic bacterium, Lactobacillus plantarum 299v, could affect Escherichia coli-induced passage of mannitol across the intestinal wall. Sprague-Dawley rats were pretreated for one week by either tube feeding with L. plantarum 299v twice daily, free access to L. plantarum 299v by adding the bacterium in the drinking water, or negative control receiving regular feeding. Intestinal segments were mounted in Ussing chambers and the mucosa was exposed to control medium, E. coli, and L. plantarum 299v (alone or together). [14C]Mannitol was added as a marker of intestinal permeability and samples were taken from the serosal side. E. coli exposure induced a 53% increase in mannitol passage across the intestinal wall (P < 0.05). One week of pretreatment with L. plantarum 299v in the drinking water abolished the E. coli-induced increase in permeability. Tube feeding for one week or short-term addition of L. plantarum 299v in the Ussing chambers had no effect on the permeability provoked by E. coli challenge. Notably, L. plantarum 299v itself did not change the intestinal passage of mannitol. These data demonstrate that pretreatment with L. plantarum 299v, which is a probiotic bacterium, protects against E. coli-induced increase in intestinal permeability, and that L. plantarum 299v alone has no influence on the intestinal permeability. Thus, this study supports the concept that probiotics may exert beneficial effects in the gastrointestinal tract.  相似文献   
50.
The involvement of several cytokines in the antitumor effect induced by intrapleural (i.pl.) injection of heat-killed cells of Lactobacillus casei strain Shirota (LC 9018) in mice was investigated. Injection of LC 9018 i.pl. into Meth A fibrosarcoma (Meth A)-bearing mice not only significantly prolonged the survival of the mice, but also effectively inhibited the accumulation of malignant pleural fluid in the thoracic cavity. In the thoracic cavity of tumor-bearing mice treated with LC 9018, we observed large amounts of several cytokines including interleukin (IL)-1β, interferon (IFN)-γ, IL-12 and tumor necrosis factor (TNF)-α. Both anti-IFN-γ and anti-IL-12 monoclonal antibody (mAb) treatments partially diminished the antitumor activity of LC 9018 in vivo, while the treatment of anti-IL-1β mAb did not influence the survival of the mice. However, anti-TNF-α mAb treatment completely abolished the antitumor effect of LC 9018 in vivo, suggesting that in this model LC 9018 has a survival-prolonging effect involving certain cytokines. Moreover, i.pl. injection of mouse recombinant TNF-α into Meth A-bearing mice pretreated with anti-TNF-α mAb partially restored the survival-enhancing effect of LC 9018. These results led us to conclude that TNF-α induced by i.pl. injection of LC 9018 plays an important role in the antitumor effect of LC 9018 in vivo. Received: 22 February 1999  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