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101.
标  题 硝苯地平胃肠治疗系统对老年患者的抗高血压治疗作用作  者 BravoEL,KrakoffLR,TuckML,etal.  参考文献 AmJHypertens,1990,3:326S目  的 评估硝苯地平的新剂型胃肠治疗系统GITS治疗高血压的疗效和安全性。研究疾病 高血压病。设  计 多中心、开放性临床研究。病人资料 1155例DBP在95~110mmHg的高血压患者。随  访 至目标血压达到后12周。治疗方案 硝苯地平控释片30mg/d,在6周内剂量逐渐增至最大量180mg/d,每次增量为30mg,目标血压为舒张压降至90…  相似文献   
102.
103.
Spectrum and origin of phenylketonuria mutations in Spain   总被引:3,自引:0,他引:3  
In order to characterize the molecular heterogeneity of phenylalanine hydroxylase deficiencies in the Spanish population, 37 PKU patients were initially screened for 16 known European mutations. For the remaining unidentified alleles, we used a combined strategy based on single strand conformation polymorphism analysis and DNA sequencing. Overall, a total of 15 different mutations were found in our sample, which account for 62% of the total mutant alleles. We also investigated the association between the mutations, haplotypes and variable number of tandem repeats described on the phenylalanine hydroxylase gene. In addition, we analyzed the geographical distribution in Spain of the two most prevalent mutations in our population: IVS10 and I65T.  相似文献   
104.
Spoligotyping was compared with RFLP fingerprinting analysis in the identification of Mycobacterium tuberculosis strains. Spoligotyping sensitivity was 97.6% with a specificity of 47%. The global probability for two strains clustered with spoligotyping to be clustered also with RFLP analysis was 33%; the probability for two strains clustered with RFLP analysis to be clustered also with spoligotyping analysis was 95%. However, comparing the two methods in five outbreak episodes, full concordance was evidenced between spoligotyping and RFLP. Moreover, we evaluated the presence of our 17 largest spoligotyping clusters in spoligotyping databases from Caribbean countries, London and Cuba. Only five out of 17 patterns were present in all the cohorts. The conditional probability comparing spoligotyping and RFLP methods related to these patterns resulted in very low concordance (range from 2 to 38%). In conclusion, we confirm that spoligotyping when used alone overestimates the number of recent transmission and does not represent a suitable method for wide clinical practice application. However, it allows to get a first good picture of strain identity in a new setting and in more localized or confined settings, the probability of reaching the same result compared to RFLP was 100% confirming the usefulness of spoligotyping in the management of epidemic events, especially in hospitals, prisons and close communities.  相似文献   
105.
Laparoscopic splenectomy has gained increasing acceptance in the surgical management of a variety of splenic disorders, in particular hematological diseases. In this series, we report our experience with 20 patients (male:female ratio of 4:16 with median age of 16 years, range 5-49 years) who underwent this procedure because of ITP in 9 cases, spherocytosis in 7 and Cooley disease, sickle cell anemia, dyserythropoietic and hemolytic anemia in one case each. The patient was placed in a supine position using a fourtrocars technique. We did not perform pre-operative splenic artery embolization in any case. Spleen lower pole and its posterolateral attachments were dissected first, using electrocautery and endoclips. Vascular hilar isolation was achieved with an EndoGIA stapler and the spleen was removed by morcelation within a retrieval bag (16 cases) or via a 4-5 cm left subcostal incision (4 cases). One patient required conversion to open technique (conversion rate 5 %), because of uncontrolled bleeding from splenic hilum. Mean operative time was 165 min (range 100-240 min), mean splenic size was 13.5 cm (range 11-20 cm), with weight ranging between 140 and 1060 g and estimated blood loss was 151 ml (75-280 ml). No patient required a blood transfusion. Median postoperative hospital stay was 4 days (range 3-8 days). Postoperative complications occurred in 2 patients (10%), with no mortality rate in this series. Regarding the low complication rate and the advantages of a small abdominal trauma in the postoperative period, such as less postoperative pain, faster hospital discharge and better cosmetic results, the laparoscopic approach for elective splenectomy in hematological disorders has a substantial benefit for the patient.  相似文献   
106.
BACKGROUND: Aortic valve replacement in elderly patients with a small aortic annulus may pose difficult problems in terms of prosthesis selection. We have evaluated the hemodynamic performance of the 21-mm Carpentier-Edwards Perimount bioprosthesis implanted in elderly patients. METHODS: From July 1996 to June 1998, 19 patients (17 women and 2 men, mean age 76+/-4 years and mean body surface area 1.73+/-0.13 m2), had aortic valve replacement with a 21-mm Carpentier-Edwards Perimount bioprosthesis. The hemodynamic performance of the valve was evaluated in 16 patients, who completed at least a 6-month follow-up interval, with transthoracic color-Doppler echocardiography with particular reference to peak and mean transprosthetic gradients, effective orifice area index, and regression of left ventricular mass index. RESULTS: There were no late deaths and no major postoperative complications. At a mean follow-up of 12+/-7 months, compared to discharge, all patients showed clinical improvement with a significant reduction of peak gradient (from 23+/-4 to 21+/-6 mm Hg, p = 0.04) and left ventricular mass index (from 181+/-23 to 153+/-20 g/m2; p<0.001), whereas mean gradient (from 13+/-3 to 13+/-4 mm Hg, p = not significant) and effective orifice area index (from 1.12+/-0.34 to 1.13+/-0.28 cm2/m2, p = not significant) remained substantially unchanged. CONCLUSIONS: The use of a 21-mm Carpentier-Edwards Perimount bioprosthesis is associated with low transprosthetic gradients and significant reduction in left ventricular hypertrophy after aortic valve replacement. The results of our study suggest that a 21-m Carpentier-Edwards Perimount bioprosthesis should be considered a valid option in elderly patients with aortic valve disease and a small aortic annulus.  相似文献   
107.
Individuals with a negative intradermal reaction to tuberculin PPD have long been described in the Mycobacterium tuberculosis exposed, immune-competent population. Here, we studied PPD-specific blood T lymphocytes from these subjects for phenotypic markers relevant to skin migration, including the expression of the skin-selective homing receptor, the cutaneous lymphocyte-associated antigen (CLA). Out of 82 patients with active tuberculosis we identified four subjects who were repeatedly PPD skin test-negative. CD4 T lymphocytes specific to mycobacterial antigens were derived from these individuals, which (i) proliferated in vitro to M. tuberculosis antigens comparably to those from PPD+ patients; (ii) secreted comparable amounts of IL-2 but lower amounts of IFN-gamma; (iii) were confined within the CLA-negative T cell subset. We conclude that the negative tuberculin reaction in a small subset of patients exposed to mycobacteria is associated with impaired production of IFN-gamma by circulating PPD-specific T cells that are lacking CLA expression. On this basis in vitro proliferation to PPD can discriminate bona fide non-responders from infected patients with a deficit in the margination of M. tuberculosis-specific T lymphocytes.  相似文献   
108.
The mechanisms involved in the maintenance of staphylococcal enterotoxin B (SEB)-induced T cell anergy are poorly understood. Here, we demonstrate that CD4+ T cell anergy induced by SEB treatment is under partial B cell control. This effect is not mediated by anti-SEB antibodies or any in vitro B cell-produced suppresser factor. At day 13 after SEB immunization, T cells from B cell-deficient mice proliferate upon in vitro stimulation with SEB. These results suggest that SEB- induced T cell anergy is reversible and that B cells have an important function in anergy maintenance in CD4+ T cells, both in vivo and in vitro.   相似文献   
109.
Human synpolydactyly (SPD) is an inherited congenital limb malformation caused by mutations in the HOXD13 gene. Heterozygotes are typically characterized by 3/4 finger and 4/5 toe syndactyly with associated duplicated digits; hands and feet of homozygotes are very small because of a shortening of the phalanges, metacarpal and metatarsal bones. Here we describe the phenotype and molecular basis of a spontaneous mutation of Hoxd13 in mice that provides a phenotypically and molecularly accurate model for human SPD. The new mutation, named synpolydactyly homolog (spdh), is a 21 bp in-frame duplication within a polyalanine- encoding region at the 5'-end of the Hoxd13 coding sequence. The duplication expands the stretch of alanines from 15 to 22; the same type of expansion occurs in human SPD mutations. spdh/spdh homozygotes exhibit severe malformations of all four feet, including polydactyly, syndactyly and brachydactylia. The phenotype of spdh is much more severe than that exhibited by mice with a genetically engineered, presumably null, disruption of Hoxd13. Thus spdh probably acts in a dominant-negative manner and will be valuable for examining interactions with other Hox genes and their protein products during limb development. Homozygous mice of both sexes also lack preputial glands and males do not breed; therefore, spdh/spdh mice may also be valuable in studies of reproductive physiology and behavior.   相似文献   
110.
目的:观察维生素C,维生素E和维生素C 维生素E联合后对胚胎中脑神经细胞生长发育的影响。方法:实验于2006-03/04在江苏大学医学院研究中心细胞培养室完成。采用16d大鼠胚胎中脑神经细胞体外培养方法,观察不同剂量的维生素C(5,10,25,50μmol/L),维生素E(10,25,50,100μmol/L)和维生素C、维生素E联合作用(维生素C25μmol/L 维生素E50μmol/L,维生素C50μmol/L 维生素E100μmol/L),培养10d后收集细胞,并利用图像分析细胞形态的变化、蛋白质、丙二醛含量及超氧化物歧化酶活性指标。结果:①维生素C、维生素E和维生素C 维生素E联合能促进体外培养中脑神经细胞突起生长,集落数增多。②与正常对照组比较,维生素C10,25μmol/L组、维生素E10,25,50μmol/L组、维生素C25μmol/L 维生素E50μmol/L组神经细胞总蛋白相对含量明显增加。③与正常对照组比较,维生素C10,25μmol/L组、维生素E25,50μmol/L组、维生素C25μmol/L 维生素E50μmol/L组神经细胞超氧化物酶活性增加,丙二醛含量降低。④维生素C50μmol/L组、维生素E100μmol/L组和维生素C50μmol/L 维生素E100μmol/L组超氧化物酶活性低于正常对照组,丙二醛含量高于正常对照组。结论:维生素C、维生素E和维生素C 维生素E联合剂量在一定范围内能够明显提高中脑神经细胞的抗氧化能力,同时能促进胚胎中脑神经细胞分化和增殖作用。  相似文献   
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