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21.
目的:探讨胸腔闭式引流联合尿激酶注入对包裹性胸腔积液的临床疗效。方法:对我院2007年2月-2011年4月收治的包裹性胸腔积液患者87例,随机分为实验组以及对照组,实验组采用胸腔闭式引流联合尿激酶注入进行治疗,对照组采用常规治疗。结果:实验组患者临床疗效明显优于对照组(P<0.05);实验组患者治疗后其积液中蛋白量以及白细胞含量明显低于对照组(P<0.05);实验组患者治疗时间、胸膜壁厚度等比较明显优于对照组(P<0.05)。结论:对包裹性胸腔积液患者采用胸腔闭式引流联合尿激酶注入进行治疗,可有效改善患者预后,提高患者临床治疗效果。  相似文献   
22.
构建截断型可溶性尿激酶型纤溶酶原激活物受体(u-PAR)的原核及酵母表达质粒并分别在大肠杆菌和Pichiapastoris酵母中高效表达.利用PCR扩增截断型可溶性u-PARcDNA片段,并分别连入酵母及原核表达载体中,构建成表达质粒.后者经诱导表达的蛋白被用于免疫家兔,获得抗u-PAR的抗血清,用于对酵母表达产物的鉴定.前者在甲醇的诱导下表达,产物分泌至培养液中.结果表明,原核表达的u-PAR蛋白免疫家兔后获得高效价的抗血清,利用此抗血清所作Westernblot证实酵母表达蛋白具有u-PAR的免疫原性,表观分子量40kD左右.Mut-表型在第5d为最高(2.5μg/ml),Mut+表型在第4d为最高(7.5μg/ml).因此,构建的可溶性u-PAR表达质粒在Pichiapastoris酵母细胞获得表达,为进一步竞争拮抗受体功能的研究奠定了基础.  相似文献   
23.
陈明云  熊莉娟  李新宪  冯杰  庹田 《生物磁学》2013,(26):5115-5118
目的:比较国产重组链激酶(r-SK)与尿激酶(uK)在急性心肌梗死(AMI)溶栓中的血管再通率。方法:对68例诊断为AMI并进行溶栓治疗的患者进行临床分组治疗,观察组36例,对照组32例,观察组治疗给予r-SK,对照组治疗给予UK。观察两组患者血管再通率、住院并发症、不良反应以及30d病死率等。结果:观察组患者总血管再通率、小于6h血管再通率以及6-12h血管再通率均明显高于对照组(P〈0.05),不良反应方面,观察组用药后轻度出血、皮疹、低血压等与对照组比较无差异(P〉0.05)。30d病死率方面,观察组为11.11%,与对照组的15.63%比较无明显差异(P〉0.05)。结论:国产r-SK进行AMI溶栓的血管再通率高,不良反应明显优于UK,30d病死率与UK相似,值得临床应用。  相似文献   
24.
目的:探讨地塞米松联合尿激酶对结核性胸膜炎的临床效果。方法:选择2013年8月到2016年5月在我院进行诊治的结核性胸膜炎患者190例,根据随机信封抽签原则分为观察组与对照组各95例,两组都给予标准抗结核治疗方案,对照组在抗结核治疗的同时给予尿激酶治疗,观察组再给予地塞米松治疗,两组都治疗1个月。治疗后,比较两组的总有效率、不良反应的发生情况、胸腔积液完全引流时间、抽出胸腔积液总量、凝血酶原时间和凝血酶时间。结果:所有患者都注射耐受良好,未见严重并发症;观察组的总有效率(88.4%)明显高于对照组(72.6%);观察组胸腔积液完全引流时间和抽出胸腔积液总量分别为7.56±2.44d和2867.33±456.10 m L,对照组分别为9.44±2.89d和1989.92±444.20 m L,观察组胸腔积液完全引流时间明显短于对照组,且抽出胸腔积液总量显著高于对照组(P0.05)。治疗后,两组的凝血酶原时间和凝血酶时间都明显高于治疗前(P0.05),且观察组显著高于对照组(P0.05)。结论:地塞米松联合尿激酶治疗结核性胸膜炎能延长凝血酶时间和凝血酶原时间,缩短胸腔积液引流时间,增加抽出胸腔积液总量,安全性和临床疗效均较好。  相似文献   
25.
Two isomeric piperidine derivatives (meta and para isomers) were used as arginine mimics in the P1 position of a cyclic peptidic inhibitor (CPAYSRYLDC) of urokinase-type plasminogen activator. The two resulting cyclic peptides showed vastly different affinities (∼70 fold) to the target enzyme. X-ray crystal structure analysis showed that the two P1 residues were inserted into the S1 specificity pocket in indistinguishable manners. However, the rest of the peptides bound in entirely different ways on the surface of the enzyme, and the two peptides have different conformations, despite the highly similar sequence. These results demonstrate how the subtle difference in P1 residue can dictate the exosite interactions and the potencies of peptidic inhibitors, and highlight the importance of the P1 residue for protease inhibition. This study provides important information for the development of peptidic agents for pharmacological intervention.  相似文献   
26.
Bone morphogenetic protein (BMP), a member of the TGF-beta superfamily, is involved in development, morphogenesis, cell proliferation and apoptosis. Dysregulation of BMP signaling has been suggested in tumorigenesis. In an analysis of human colon normal mucosa and tumors at different stages by immunohistochemistry, we observed that the intensity of BMP-4 staining in late-adenocarcinomas was stronger than that in normal mucosa and adenomas, while there was no difference in the staining of its receptors (BMPR-IA and BMPR-II) at all stages. The up-regulation of BMP-4 was further validated in another panel of tumor tissues by real-time RT-PCR, showing that BMP-4 mRNA levels in primary colonic carcinomas with liver metastasis were significantly higher than that in the matched normal mucosa. In order to understand the functional relevance of BMP-4 expression in colon cancer progression, BMP-4-overexpressing cell clones were generated from HCT116 cells. Overexpression of BMP-4 did not affect the HCT116 cell growth. The cells overexpressing BMP-4 became resistant to serum-starvation-induced apoptosis and exhibited enhanced migration and invasion characteristics. Overexpression of BMP-4 changed cell morphology to invasive spindle phenotype and induced the expression and activity of urokinase plasminogen activator (uPA). These results indicate that BMP-4 confers invasive phenotype during progression of colon cancer.  相似文献   
27.
To understand the contribution of epidermal melanocytes in the proteolytic potential of human skin, we have studied melanocytes grown in a low-serum medium deprived of phorbol esters, cholera toxin, and other non-physiological supplements. We focused on the plasminogen activation system and certain matrix metalloproteinases (gelatinases). Supposing that the proteolytic activity of cells can influence binding to collagen matrix and its reorganization, we have analyzed these parameters as well. We found that human melanocytes secreted tissue-type plasminogen activator and utilised it to generate cell-bound plasmin. No urokinase-type plasminogen activator was detected in the cultures but its receptor was found in cell extracts. Both the 72 kDa and 92 kDa gelatinases were secreted by the cells and in equal amounts. In addition, melanocytes secreted the wide-spectrum proteinase inhibitor alpha-2-macroglobulin. Melanocytes cast into collagen matrices retained a rounded morphology, did not extend processes, and were unable to contract collagen lattices. As a control, these parameters were investigated in parallel in cultures of human keratinocytes, dermal fibroblasts, and two melanoma cell lines. The obtained characteristics suggest that normal human melanocytes are proteolytically active cells. This function may pertain to skin physiology and pathophysiology.  相似文献   
28.
Plasminogen activation catalyzed by urokinase-type plasminogen activator (uPA) plays an important role in normal and pathological tissue remodeling processes. Since its discovery in the mid-1980s, the cell membrane-anchored urokinase-type plasminogen activator receptor (uPAR) has been believed to be central to the functions of uPA, as uPA-catalyzed plasminogen activation activity appeared to be confined to cell surfaces through the binding of uPA to uPAR. However, a functional uPAR has so far only been identified in mammals. We have now cloned, recombinantly produced, and characterized two zebrafish proteases, zfuPA-a and zfuPA-b, which by several criteria are the fish orthologs of mammalian uPA. Thus, both proteases catalyze the activation of fish plasminogen efficiently and both proteases are inhibited rapidly by plasminogen activator inhibitor-1 (PAI-1). But zfuPA-a differs from mammalian uPA by lacking the exon encoding the uPAR-binding epidermal growth factor-like domain; zfuPA-b differs from mammalian uPA by lacking two cysteines of the epidermal growth factor-like domain and a uPAR-binding sequence comparable with that found in mammalian uPA. Accordingly, no zfuPA-b binding activity could be found in fish white blood cells or fish cell lines. We therefore propose that the current consensus of uPA-catalyzed plasminogen activation taking place on cell surfaces, derived from observations with mammals, is too narrow. Fish uPAs appear incapable of receptor binding in the manner known from mammals and uPA-catalyzed plasminogen activation in fish may occur mainly in solution. Studies with nonmammalian vertebrate species are needed to obtain a comprehensive understanding of the mechanism of plasminogen activation.  相似文献   
29.
30.
Administration of quercetin, a common polyphenolic component of many vascular and edible plants including vegetables, fruits and tea significantly reduced the tumor volume in rats induced for mammary carcinoma using dimethyl benz (a) anthracene (DMBA). Dose response was assessed, by treating the animals with different doses (15-45 mg/kgbw) of quercetin and 25 mg/kgbw was taken as effective dose. Quercetin was administered as an intra tumoral injection once a week for 4 weeks. Serum levels of carcino embryonic antigen (CEA), a potent marker for tumor growth and invasion was significantly decreased on quercetin treatment. Quercetin caused a significant decrease in the activities of acid phosphatase and Cathepsin D in serum of experimental animals. Activities of lysosomal enzymes- (beta-D galactosidase, beta-D glucuronidase, beta-D glucosidase and sialidase), in serum and tissue were significantly altered in DMBA animals compared to control animals. However, quercetin treatment caused no significant change in lysosomal enzyme activities in tissues, whereas the activities were significantly lowered in serum. Partial purification of tissue type plasminogen activator (t-PA) from the tumor and kidney showed increased activity in the DMBA induced animals. Serum urokinase, -like plasminogen activator (u-PA) was also increased in animals with tumor, indicating tumor invasion. Administration of quercetin caused a significant decrease of both t-PA and u-PA. In conclusion, the present study suggests the possible role of quercetin in primary and invasive mammary tumor treatment. The above observations in vivo warrant further studies, due to the easy availability, common occurrence and low toxicity of this dietary bioflavonoid.  相似文献   
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