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991.
Endoscopic sclerotherapy as compared with endoscopic ligation for bleeding esophageal varices. 总被引:30,自引:0,他引:30
G V Stiegmann J S Goff P A Michaletz-Onody J Korula D Lieberman Z A Saeed R M Reveille J H Sun S R Lowenstein 《The New England journal of medicine》1992,326(23):1527-1532
BACKGROUND. Endoscopic sclerotherapy is an accepted treatment for bleeding esophageal varices, but it is associated with substantial local and systemic complications. Endoscopic ligation, a new form of endoscopic treatment for bleeding varices, may be safer. We compared the effectiveness and safety of the two techniques. METHODS. In this randomized trial we compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices. Sixty-five patients were treated with sclerotherapy, and 64 with ligation. Initial treatment for acute bleeding was followed by elective retreatment to eradicate varices. The patients were followed for a mean of 10 months, during which we determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival. RESULTS. Active bleeding at the first treatment was controlled by sclerotherapy in 10 of 13 patients (77 percent) and by ligation in 12 of 14 patients (86 percent). Slightly more sclerotherapy-treated patients had recurrent hemorrhage during the study (48 percent vs. 36 percent for the ligation-treated patients, P = 0.072). The eradication of varices required a lower mean (+/- SD) number of treatments with ligation (4 +/- 2 vs. 5 +/- 2, P = 0.056) than with sclerotherapy. The mortality rate was significantly higher in the sclerotherapy group (45 percent vs. 28 percent, P = 0.041), as was the rate of complications (22 percent vs. 2 percent, P less than 0.001). The complications of sclerotherapy were predominantly esophageal strictures, pneumonias, and other infections. CONCLUSIONS. Patients with cirrhosis who have bleeding esophageal varices have fewer treatment-related complications and better survival rates when they are treated by esophageal ligation than when they are treated by sclerotherapy. 相似文献
992.
Conversion of myoblasts to physiologically active neuronal phenotype 总被引:13,自引:0,他引:13
Watanabe Y Kameoka S Gopalakrishnan V Aldape KD Pan ZZ Lang FF Majumder S 《Genes & development》2004,18(8):889-900
993.
The value of pleural fluid anti-A60 IgM in BCG-vaccinated tuberculous pleurisy patients 总被引:1,自引:0,他引:1
E. Kunter K. Cerrahoglu A. Ilvan T. Isitmangil O. Turken O. Okutan Z. Kartaloglu S. Cavuslu 《Clinical microbiology and infection》2003,9(3):212-220
Objectives To determine if detection of IgM and IgG antibodies against mycobacterial antigen A60, together with the Mantoux tuberculin skin test (TST), could be used in the diagnosis of tuberculous pleurisy (TP) in BCG-vaccinated cases.
Methods We investigated 125 BCG-vaccinated patients with pleural effusion. Of these, 88 had TP and 37 had non-tuberculous pleurisy (NTP). TST and anti-A60 IgM and IgG measurements by ELISA were performed in the sera and pleural effusions of both groups.
Results Cut-off values, in optical density, for serum anti-A60 IgM, pleural fluid anti-A60 IgM, serum anti-A60 IgG and pleural fluid anti-A60 IgG were defined as 0.624, 0.614, 0.464, and 0.613, respectively. TP patients had higher IgG and IgM levels in the serum ( P < 0.001 and P < 0.05, respectively) and pleural effusion ( P < 0.001 and P < 0.001, respectively). Regardless of the diagnosis, IgG and IgM levels were higher in the sera ( P < 0.001 and P < 0.05, respectively) and pleural effusions ( P < 0.001 and P < 0.001, respectively) of TST-positive cases, and serum and pleural fluid IgM levels were higher ( P < 0.001 and P < 0.001, respectively) in the TST-positive TP cases. Sensitivity and specificity of TST were 65% and 68%, respectively. As a single parameter, pleural fluid anti-A60 IgM had the highest sensitivity (77%) and specificity (94%) in patients with negative TST.
Conclusion We suggest that in populations where tuberculosis prevalence is high and BCG vaccination is common, pleural fluid anti-A60 IgM can facilitate the diagnosis of TP. 相似文献
Methods We investigated 125 BCG-vaccinated patients with pleural effusion. Of these, 88 had TP and 37 had non-tuberculous pleurisy (NTP). TST and anti-A60 IgM and IgG measurements by ELISA were performed in the sera and pleural effusions of both groups.
Results Cut-off values, in optical density, for serum anti-A60 IgM, pleural fluid anti-A60 IgM, serum anti-A60 IgG and pleural fluid anti-A60 IgG were defined as 0.624, 0.614, 0.464, and 0.613, respectively. TP patients had higher IgG and IgM levels in the serum ( P < 0.001 and P < 0.05, respectively) and pleural effusion ( P < 0.001 and P < 0.001, respectively). Regardless of the diagnosis, IgG and IgM levels were higher in the sera ( P < 0.001 and P < 0.05, respectively) and pleural effusions ( P < 0.001 and P < 0.001, respectively) of TST-positive cases, and serum and pleural fluid IgM levels were higher ( P < 0.001 and P < 0.001, respectively) in the TST-positive TP cases. Sensitivity and specificity of TST were 65% and 68%, respectively. As a single parameter, pleural fluid anti-A60 IgM had the highest sensitivity (77%) and specificity (94%) in patients with negative TST.
Conclusion We suggest that in populations where tuberculosis prevalence is high and BCG vaccination is common, pleural fluid anti-A60 IgM can facilitate the diagnosis of TP. 相似文献
994.
郭禹君陆文君杨书龙李昭铸 《中国组织工程研究》2023,(1):138-144
背景:尿源干细胞为尿液中存在的间充质干细胞,具备自我增殖与多向分化的潜能,由于其本身存在于泌尿系统,并且很可能来源于肾脏组织,相较于其他间充质干细胞存在先天的优势,因此尿源干细胞及其外泌体可能具备对于肾脏病的特殊干预作用。目的:综述尿源干细胞及其外泌体的生物学特性,以及二者在肾脏病领域的应用进展,以期为临床肾脏疾病的治疗提供新思路。方法:以“urine-derived stem cell*,urine-derived stromal cell*,urine-derived mesenchymal stem cell*,urine-derived mesenchymal stromal cell*,urine-derived progenitor cell*,kidney diseases,acute kidney injury,diabetic nephropathies,kidney failure,chronic,tissue engineering,organoids”为检索词检索PubMed数据库,以“尿源干细胞,急性肾损伤,慢性肾病,糖尿病肾病,组织工程,类器官”为检索词检索CNKI数据库,发表时间限定为2000年1月至2021年10月。检索后严格按照纳入和排除标准进行人为筛选,最终纳入31篇文献进行综述。结果与结论:①尿源干细胞作为泌尿系统来源的间充质干细胞,具备间充质干细胞共有的特性。此外,其在肾脏病领域是一种有效的干预措施和适宜的种子细胞来源;②尿源干细胞及其外泌体在急性肾损伤动物及细胞模型上,可以显著缓解肾功能损害和组织学损伤,抑制炎症、细胞凋亡和氧化应激;在慢性肾脏病(包括糖尿病肾病)方面,尿源干细胞及其外泌体可以延缓肾功能进展及组织学改变,抑制炎症细胞浸润及纤维化,发挥对足细胞的保护作用;此外,其在肾脏组织工程与再生医学领域的应用也同样具有广阔的前景;③虽然尿源干细胞及其外泌体在肾脏病领域的研究尚处于初始阶段,但已体现出较大的潜力和价值,在未来有望成为临床肾脏病治疗的有效手段之一。 相似文献
995.
Structure-function relationships for human antibodies to pneumococcal capsular polysaccharide from transgenic mice with human immunoglobulin Loci 下载免费PDF全文
To investigate the influence of antibody structure and specificity on antibody efficacy against Streptococcus pneumoniae, human monospecific antibodies (MAbs) to serotype 3 pneumococcal capsular polysaccharide (PPS-3) were generated from transgenic mice reconstituted with human immunoglobulin loci (XenoMouse mice) vaccinated with a PPS-3-tetanus toxoid conjugate and their molecular genetic structures, epitope specificities, and protective efficacies in normal and complement-deficient mice were determined. Nucleic acid sequence analysis of three MAbs (A7, 1A2, and 7C5) revealed that they use two different V(H)3 genes (A7 and 1A2 both use V3-15) and three different V(kappa) gene segments. The MAbs were found to have similar affinities for PPS-3 but different epitope specificities and CDR3 regions. Both A7 and 7C5 had a lysine at the V(H)-D junction, whereas 1A2 had a threonine. Challenge experiments with serotype 3 S. pneumoniae in BALB/c mice revealed that both 10- and 1- micro g doses of A7 and 7C5 were protective, while only a 10- micro g dose of 1A2 was protective. Both A7 and 7C5 were also protective in mice lacking either an intact alternative (FB(-/-)) or classical (C4(-/-)) complement pathway, but 1A2 was not protective in either strain. Our data suggest that PPS-3 consists of epitopes that can elicit both highly protective and less protective antibodies and that the superior efficacies of certain antibodies may be a function of their structures and/or specificities. Further investigation of relationships between structure, specificity, and efficacy for defined MAbs to PPS may identify antibody features that might be useful surrogates for antibody (and vaccine) efficacy. 相似文献
996.
Zúñiga MC 《Virus research》2002,88(1-2):17-33
The poxviruses have evolved a diverse array of proteins which serve to subvert innate and adaptive host responses that abort or at least limit viral infections. Myxoma virus and its rabbit host are considered to represent an ideal poxvirus-host system in which to study the effects of these immunomodulatory proteins. Studies of laboratory rabbits (Oryctolagus cuniculus) infected with gene knockout variants of myxoma virus have provided compelling evidence that several myxoma virus gene products contribute to the pathogenic condition known as myxomatosis. However, myxomatosis, which is characterized by skin lesions, systemic immunosuppression, and a high mortality rate, does not occur in the virus' natural South American host, Sylvilogus brasiliensis. Moreover, in Australia where myxoma virus was willfully introduced to control populations of O. cuniculus, myxomatosis-resistant rabbits emerged within a year of myxoma virus introduction into the field. In this review I discuss the characterized immunomodulatory proteins of myxoma virus, their biochemical properties, their pathogenic effects in laboratory rabbits, the role of the host immune system in the susceptibility or resistance to myxomatosis, and the evidence that immunomodulatory genes may have been attenuated during the co-adaptation of myxoma virus and O. cuniculus in Australia. 相似文献
997.
This study was conducted to evaluate the ability of the BacT/Alert automated blood culture system to detect Brucella spp. in comparison with traditional Brucella broth culture. Overall, 100 (50 bone marrow and 50 blood samples) paired cultures were obtained, and 59 were positive by at least one method. The Brucella broth culture method detected all 59 positive cultures (100%), and the BacT/Alert system detected 30 (50.8%) ( P < 0.05). The mean detection times for B. melitensis were 4.5 days in the BacT/Alert system and 5 days in Brucella broth culture ( P > 0.05). There is no significant difference between the two methods with respect to growth time of the microorganism, but Brucella broth culture is more sensitive than the BacT/Alert system. 相似文献
998.
Harold Z. Hirsch Andrej Tarkowski William J. Koopman Jiri Mestecky 《Journal of clinical immunology》1989,9(4):273-278
The enzyme-linked immunospot assay was used to enumerate both the number and the frequency of spontaneous IgG, IgA, and IgM immunoglobulin-secreting cells and IgA- and IgM-rheumatoid factor (RF)-producing cells present in the gingivae and peripheral blood of adult periodontitis patients. Cells from 29 patients were incubated on plates coated with human IgG, Fc, or F(ab)2 fragments and on plates coated with class-specific antihuman antibodies and secreted antibodies were subsequently visualized by means of an immunoenzymatic procedure. The data indicate that (1) IgA-RF- and IgM-RF-secreting cells are frequently present in the gingiva of adult periodontitis patients; (2) production of RF in gingivae of adult periodontitis patients occurs in the absence of demonstrable RF production by simultaneously obtained peripheral blood mononuclear cells, suggesting that local autoimmune reactions may occur in this disease; and (3) lack of correlation between IgA-RF and IgM-RF production in diseased gingiva suggests that the two RF isotypes are regulated independently of each other. 相似文献
999.
1000.
散发性急性戊型肝炎血清抗体动态变化和肝脏超微… 总被引:1,自引:0,他引:1
为探讨散发性戊型肝为血清抗体动态变化,应用酶联免疫法(EIA)检测了7例急性戊型肝炎抗戊型肝炎病毒(HEV)IgG和IgM抗体、并对1例2进行了肝超微结构病理检测,结果表明,发病10天至45天内抗HEV-IgG和IgM滴度最高,发病第40天仍有肝细胞肿胀,胞浆空化和线粒体固缩等病理变化。患者轿清抗-HEVIgM滴度在45天后逐渐下降,2个月内全中消失,抗-HEVIgM滴度在45天后逐渐下降,2个月 相似文献