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11.
Recurrent loss-of-function mutations of spliceosome gene, ZRSR2, occur in myelodysplastic syndromes (MDS). Mutation/loss of ZRSR2 in human myeloid cells primarily causes impaired splicing of the U12-type introns. In order to further investigate the role of this splice factor in RNA splicing and hematopoietic development, we generated mice lacking ZRSR2. Unexpectedly, Zrsr2-deficient mice developed normal hematopoiesis with no abnormalities in myeloid differentiation evident in either young or ≥1-year old knockout mice. Repopulation ability of Zrsr2-deficient hematopoietic stem cells was also unaffected in both competitive and non-competitive reconstitution assays. Myeloid progenitors lacking ZRSR2 exhibited mis-splicing of U12-type introns, however, this phenotype was moderate compared to the ZRSR2-deficient human cells. Our investigations revealed that a closely related homolog, Zrsr1, expressed in the murine hematopoietic cells, but not in human cells contributes to splicing of U12-type introns. Depletion of Zrsr1 in Zrsr2 KO myeloid cells exacerbated retention of the U12-type introns, thus highlighting a collective role of ZRSR1 and ZRSR2 in murine U12-spliceosome. We also demonstrate that aberrant retention of U12-type introns of MAPK9 and MAPK14 leads to their reduced protein expression. Overall, our findings highlight that both ZRSR1 and ZRSR2 are functional components of the murine U12-spliceosome, and depletion of both proteins is required to accurately model ZRSR2-mutant MDS in mice.  相似文献   
12.
Urinary ascites is a rare diagnosis, commonly associated with bladder rupture. We present a case of intraperitoneal bladder injury following a Cesarean section with subsequent development of urinary ascites. Initial laboratory data with elevated serum creatinine and blood urea nitrogen (BUN) raised the suspicion for acute kidney injury due to the recent obstetrical procedure. This case highlights the importance of including intraperitoneal bladder injury with urinary ascites as a key differential in the workup of acute renal failure, particularly in the obstetric surgical setting. The rapid development of ascites with elevated serum BUN and creatinine should prompt work up for evaluating intraperitoneal bladder injury. Early diagnosis and treatment can yield gratifying results and avoid unnecessary workup of other causes of renal failure.  相似文献   
13.
广地龙中促进子宫收缩的成分   总被引:1,自引:0,他引:1  
徐叔云  孙鼎兴  尹留康  邢文 《药学学报》1964,11(11):729-734
本文研究了自广地龙中提出来的一种引湿性、淡黄色針状結晶(含量約0.2%)对平滑肌器官(特别是对子宮)的作用。介紹了該結晶的提取方法。該結晶0.1毫克加入25毫升Locke液中,能使已孕和未孕大鼠或豚鼠离体子宮角紧张度明显升高,0.3毫克可使之呈痙攣收縮状态。按1毫克/公斤給已孕和未孕麻醉家兔靜脉注射后15—30分钟,在位子宮紧张度升高,作用維持1.5—3小时。按8—10毫克/公斤注射,子宮紧张度立卽升高和血压急剧下降到零而死亡。9只慢性子宫瘻家兔靜脉注射(3—6毫克/公斤)或灌胃給药(10—20毫克/公斤)后15—45分钟,子宮收縮明显增强,作用維持1.5—3小时(注射給药)和7小时以上(灌胃給药)。多数实驗家兔在子宮兴奋同时有排便現象。該結晶对家兔在位腸管和大鼠后肢血管均有强烈兴奋作用,但对豚鼠支气管肌作用极弱。当給小鼠靜脉注射时,LD50为38.7毫克/公斤。  相似文献   
14.
15.
Odontogenic sinusitis is a well-recognized condition and accounts for approximately 10% to 12% of cases of maxillary sinusitis. An odontogenic source should be considered in patients with symptoms of maxillary sinusitis who give a history positive for odontogenic infection or dentoalveolar surgery or who are resistant to standard sinusitis therapy. Diagnosis usually requires a thorough dental and clinical evaluation with appropriate radiographs. Common causes of odontogenic sinusitis include dental abscesses and periodontal disease perforating the Schneidarian membrane, sinus perforations during tooth extraction, or irritation and secondary infection caused by intra-antral foreign bodies. The typical odontogenic infection is now considered to be a mixed aerobic-anaerobic infection, with the latter outnumbering the aerobic species involved. Most common organisms include anaerobic streptococci, Bacteroides, Proteus, and Coliform bacilli. Typical treatment of atraumatic odontogenic sinusitis is a 3- to 4- week trial of antibiotic therapy with adequate oral and sinus flora coverage. When indicated, surgical removal of the offending odontogenic foreign body (primary or delayed) or treatment of the odontogenic pathologic conditions combined with medical therapy is usually sufficient to cause resolution of symptoms. If an oroantral communication is suspected, prompt surgical management is recommended to reduce the likelihood of causing chronic sinus disease.  相似文献   
16.
We have previously described the expression of interleukin cytokines (IL)-1alpha, IL-1beta, and IL-1 receptor antagonist (IL-1ra) in human breast cancer (HBC) tissue. Based on our previous studies, we hypothesize that the IL-1 family of cytokines, antagonists (IL-1ra) and receptors (IL-1RI and IL-1RII) are present within the human breast cancer (HBC) tumor microenvironment and that the IL-1 network of cytokines and receptors within the tumor microenvironment can control tumor cell subpopulation expression of other protumorigenic cytokines such as the angiogenic/growth factor, interleukin-8 (IL-8). To test this hypothesis we characterized the in vivo expression of the IL-1 network in HBC tissues and homogenates by immunohistochemistry (IHC) and ELISA. Additionally, we examined IL-1R expression in HBC cell lines in vitro and in a murine xenograft model by IHC. Finally, we determined the ability of IL-1 to induce IL-8 expression in in vitro using HBC cell lines. We observed that not only are the IL-1 cytokines present in HBC tissue and homogenates, but that IL-1Rs and IL-8 are also present in the HBC tumor microenvironment. Additionally, expression levels for some members of the IL-1/IL-8 network of cytokines correlated with the prognostic indicators, ER/PR. Using HBC cell lines, we observed that HBC cell lines express IL-1Rs in vitro and in the xenograft model. Furthermore, in vitro, HBC cell lines show a spectrum of responsiveness to IL-1 as measured by expression the proangiogenic/mitogenic cytokine IL-8. Our data clearly demonstrate the presence and distribution of IL-1 cytokines and receptors in HBC and suggests that the local expression of IL-1 results in the activation of a population of cells within the HBC tumor microenvironment. This activation of the IL-1/IL-1R cytokine family via autocrine and/or paracrine mechanisms leads to a cascade of secondary protumorigenic cytokines. These secondary signals induce the expression of numerous protumorigenic activities such as the expression of IL-8, and subsequently contribute to angiogenesis, tumor proliferation, and tumor invasion.  相似文献   
17.
玻璃体切除术治疗外伤性眼内炎62例   总被引:2,自引:1,他引:2  
王金兰  蒋宏苏  惠延年 《医学争鸣》2000,21(2):S018-S018
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…  相似文献   
18.
In order to understand how the brain prepares for and executes a switch in task demand, we measured reaction time (RT), accuracy, and event-related brain potentials associated with performance in single and mixed-task blocks using a cued design. Our results show that trials which repeat in a mixed-task block (repeat trials) were more demanding than trials which repeated in a single-task block, as reflected by the presence of a RT mixing cost and by the presence of a smaller target-locked positivity (P3b) on repeat trials. Within a mixed-task block, repeat and switch trials also differed, where repeat trials showed evidence of greater preparation (larger cue-locked negativity), more efficient target processing (larger target-locked P3b), and shorter RTs. In addition, the cue-locked negativity difference remained despite equating repeat and switch trials on RT, suggesting that this negativity difference is specific to the switching process. Our results are discussed in light of existing models of task switching.  相似文献   
19.
目的:了解中国不同地区间中老年人群膝关节骨性关节炎患病危险因素。方法:调查时间为2005—07/08。①从中国六大行政区(西北,华北,华东。中南,东北,西南)选出六城市(西安,石家庄,上海。广州,哈尔滨市,成都),用分层多阶段整群抽样方法,抽取6218名40岁及以上具有正式户口常住男女人群进行膝关节骨性关节炎的流行病学问卷调查(包括一般情况、现病史、既往史、体格检查、X射线片检查情况和疾病诊断6个方面,共计94个问题141个变量指标),并对其中4808名有症状者进行X射线平片膝正侧位投照。②膝关节骨性关节炎诊断标准为临床症状阳性加X射线Kellgren & Lawrence分级二级及以上者。③计算患病率,并采用Epilnf06.0和SPSS 10.0软件对其中83个变量进行多因素非条件Logistfc回归分析,表示疾病与暴露因素之间联系强度的指标用比值比(OR),若OR〉1,说明疾病发生危险性增加,与暴露因素呈正关联;若OR〈1,说明疾病发生危险性减少,与暴露因素呈负关联。 结果:①六城市膝关节骨性关节炎总患病率为15.6%,其中西安7.7%,石家庄11.2%,上海9.8%。广州30.5%,哈尔滨16.9%,成都17.5%,各城市患病率比较差异显著(P〈0.01)。②Logistic回归分析膝关节骨性关节炎在大部分城市有共同的危险因素如年龄大(OR=1.032—1.181),使用蹲坑排便年限长(OR=1.021-1.077),体质量高(OR=1.048—1.073),和开始饮酒年龄大(OR=1.008~1.028);而从事专职体育运动(OR=1.651,西安),骨质疏松病史(OR=3.311,石家庄),吸烟(OR=2.654,石家庄),类风湿关节炎病史(OR=4.964,上海),文化程度高(OR=2.593,上海),女性(OR=2.510,广州),姐妹骨关节炎史(OR=13.251,哈尔滨),母亲骨关节炎史(OR=5.683,成都)等危险因素分别在不同地区出现. 结论:年龄大、使用蹲坑排便年限长、体质量高和开始饮酒年龄大是中国六地区膝关节骨性关节炎患病的共同危险因素,同时,不同地区主要危险因素又有一定差异。  相似文献   
20.
Chronic kidney disease and end-stage renal disease are a growing epidemic, both in the United States and worldwide. African–Americans are disproportionately afflicted with kidney disease. The reasons for this disparity are multiple, but ultimately unclear. Not only are diabetes mellitus and hypertension more prevalent in African–Americans, but also end-organ damage from these processes appears also to be accelerated. Also, certain primary and secondary glomerular diseases are more prevalent and more severe in African–Americans than in Caucasians. Despite controlling for these factors and socioeconomic status, the increased prevalence of kidney disease in African–Americans is still not entirely explained. Recently, two studies identified certain alleles within the MYH9 gene locus that are more frequently expressed in African–Americans with focal segmental glomerulosclerosis and non-diabetic renal disease. These studies emphasize the important role that genetic factors may play in explaining racial discrepancies in kidney disease, and represent exciting areas for new research.  相似文献   
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