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排序方式: 共有998条查询结果,搜索用时 62 毫秒
1.
目的:分析四肢关节专用低场强MRI诊断膝关节损伤的临床应用价值。 方法:于2004-12/2005-10解放军总医院全军骨科研究所收治经手术、关节镜检查或临床证实的膝关节损伤患者40例(43个膝关节)。应用Atorscan0.2T永磁型四肢关节专用低场强磁共振机,对膝关节损伤的MRI表现进行分析。 结果:四肢关节专用低场强MRI对半月板、前交叉韧带、骨挫伤等均可作出正确诊断。 结论:四肢关节专用低场强MRI对膝关节损伤的综合诊断具有重要意义,是膝关节损伤较理想的一种非创伤性检查方法。  相似文献   
2.
There is abundant evidence of immune modulation induced by exposure to blood transfusions. Some studies have demonstrated a detrimental effect of transfusion on the recurrence of malignant disease and survival. We retrospectively studied the impact of blood transfusion exposure on 229 patients with breast cancer who were seen from July 1973 to September 1980, had at least 5 years' follow-up and had been randomized by therapy at the time of diagnosis. The patients were divided into four groups according to transfusion history: Group 1 (111 patients), no transfusion; Group 2 (34 patients), first transfusion after mastectomy; Group 3 (41 patients), first transfusion at mastectomy; and Group 4 (43 patients), first transfusion before mastectomy. All transfused patients received red cells or whole blood or both. At the time of analysis, 124 (54%) of the patients had died. Only Group 2 was statistically associated with decreased survival; recurrence of disease was 85 percent in this group, compared with 53 percent to 61 percent in the other three groups (p = 0.006, log-rank test). In general, Group 2 patients received transfusions because of recurrent disease. We conclude that transfusions before or at mastectomy are not associated with increased recurrence or reduced survival in patients with breast cancer.  相似文献   
3.
目的:观察人脂肪干细胞复合脱细胞软骨基质支架在生物反应器中初步构建组织工程软骨的可行性。方法:实验于2005-04/2006-05在解放军总医院骨科研究所完成。脂肪组织和关节软骨均来自膝关节置换术中切除的组织,并经患者知情同意。关节软骨冻干后经粉碎机粉碎,过筛,选取25~38μm大小的软骨微粒。在样品中先加入2.5g/L胰蛋白酶,37℃消化24h,再加入1%Triton X-100震荡72h。将软骨微粒和蒸馏水按1∶3的比例混合后滴加在模板中,置入冷冻干燥机冻干后行紫外线交联。紫外线照射8h完成。最后经25kGy 60Co辐照灭菌完成支架制备。取膝关节置换术中切除的髌下脂肪垫,酶消法获得脂肪干细胞,扩增后复合于脱细胞软骨基质制成圆柱状三维支架上(细胞密度5×1010L-1),置于生物反应器中进行诱导培养,同时设静态培养组作为对照,3周后观测大体形态和组织学形态变化,同时进行组织化学(包括番红花O,阿利新蓝染色)和Ⅱ型胶原免疫组织化学分析。结果:生物反应器组诱导培养3周苏木精-伊红染色显示支架结构消失,只有中心区域残存少量支架结构;静态培养组支架结构尚存在,有少量基质分泌。番红花O染色显示生物反应器组细胞外有大量蛋白聚糖沉积,阿利新蓝染色表明有软骨特异性蛋白多糖的聚集;而静态培养组只有部分区域染色且淡于生物反应器组。Ⅰ型胶原免疫组化的结果显示,在生物反应器组细胞能够合成大量软骨细胞特异性胶原成分,而静态培养组呈弱阳性。结论:生物反应器培养明显促进了脂肪干细胞的增殖与软骨分化,是体外构建组织工程软骨的良好方法。  相似文献   
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5.
Pulmonary arterial hypertension (PAH) is a life-threatening disease of varied etiologies. Although PAH has no curative treatment, a greater understanding of pathophysiology, technological advances resulting in early diagnosis, and the availability of several newer drugs have improved the outlook for patients with PAH. Sildenafil is one of the therapeutic agents used extensively in the treatment of PAH in children, as an off-label drug. In 2012, the United States Food and Drug Administration (USFDA) issued a warning regarding the of use high-dose sildenafil in children with PAH. This has led to a peculiar situation where there is a paucity of approved therapies for the management of PAH in children and the use of the most extensively used drug being discouraged by the regulator. This article provides a review of the use of sildenafil in the treatment of PAH in children.KEY WORDS: Child, phosphodiesterase (PDE)-5 inhibitor, Pulmonary hypertension therapy  相似文献   
6.
Bacterial lipopolysaccharides (LPS) are structural components of the outer membranes of Gram-negative bacteria and also are potent inducers of inflammation in mammals. Higher vertebrates are extremely sensitive to LPS, but lower vertebrates, like fish, are resistant to their systemic toxic effects. However, the effects of LPS on the fish intestinal mucosa remain unknown. Edwardsiella ictaluri is a primitive member of the Enterobacteriaceae family that causes enteric septicemia in channel catfish (Ictalurus punctatus). E. ictaluri infects and colonizes deep lymphoid tissues upon oral or immersion infection. Both gut and olfactory organs are the primary sites of invasion. At the systemic level, E. ictaluri pathogenesis is relatively well characterized, but our knowledge about E. ictaluri intestinal interaction is limited. Recently, we observed that E. ictaluri oligo-polysaccharide (O-PS) LPS mutants have differential effects on the intestinal epithelia of orally inoculated catfish. Here we evaluate the effects of E. ictaluri O-PS LPS mutants by using a novel catfish intestinal loop model and compare it to the rabbit ileal loop model inoculated with Salmonella enterica serovar Typhimurium LPS. We found evident differences in rabbit ileal loop and catfish ileal loop responses to E. ictaluri and S. Typhimurium LPS. We determined that catfish respond to E. ictaluri LPS but not to S. Typhimurium LPS. We also determined that E. ictaluri inhibits cytokine production and induces disruption of the intestinal fish epithelia in an O-PS-dependent fashion. The E. ictaluri wild type and ΔwibT LPS mutant caused intestinal tissue damage and inhibited proinflammatory cytokine synthesis, in contrast to E. ictaluri Δgne and Δugd LPS mutants. We concluded that the E. ictaluri O-PS subunits play a major role during pathogenesis, since they influence the recognition of the LPS by the intestinal mucosal immune system of the catfish. The LPS structure of E. ictaluri mutants is needed to understand the mechanism of interaction.  相似文献   
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8.
The Wisconsin Card Sorting Test (WCST) is a popular neuropsychological measure of executive dysfunction that has been researched with regard to invalid performances, a subset of which in a forensic context could be associated with malingering. In the first of three studies, WCST multivariate approaches identified in prior research (Bernard, McGrath, & Houston, 1996; Suhr & Boyer, 1999), as well as newly created variables, were used to differentiate 33 chronic traumatic brain injury (TBI) patients with good effort and 27 patients with probable insufficient effort (IE). Newly created variables that were derived logically based upon hypotheses regarding strategies that might be employed by malingerers were not effective in differentiating TBI and IE groups. Application of previously researched validity indicators based upon commonly used WCST variables, individually, and within new logistic regression findings were reasonably effective in differentiating TBI and IE groups. In order to determine whether results would vary in different TBI samples, these validity indicators were examined in Study 2 with 75 moderate and severe, acute TBI rehabilitation patients whose posttraumatic amnesia had just resolved. Statistically significant differences were present between the IE group of Study 1 and the rehabilitation patient group of Study 2 on failures to maintain set, number of trials to achieve first correct category, and number of categories completed. All these measures were performed more poorly by the IE group. However, previously used multivariate approaches and the logistic regression analysis developed in Study 1 ranged widely in the degree to which Study 2's more acute rehabilitation patients were correctly classified. Specifically, the discriminant function of Bernard and colleagues correctly classified 73% and the Suhr and Boyer logistic regression correctly classified 75% of the Study 2 participants. The Study 1 logistic regression classified 97% of the Study 2 participants correctly. In Study 3, 130 mild to severe TBI patients in the VA system were studied. The Study 1 IE group performed significantly worse than the more acute and more severe VA TBI group on all 10 common WCST variables of interest. Application of the three multivariate procedures resulted in good to excellent classification rates: Suhr and Boyer logistic regression 85%, Bernard et al. discriminant function 85%, and Study 1 logistic regression 99%. The aggregate discussion of the three studies focuses on apparent differences in samples associated with varying degrees of success in identifying TBI patients. Application of these validity indicators in forensic situations should consider that some of these multivariate approaches possess possible classification limitations associated with chronicity and severity of the reported TBI. Only the Study 1 logistic regression demonstrated improved classification rates with the more acute and severe patients of Study 2 and Study 3. As with all validity indicators, use of any WCST IE criteria in solation would not be appropriate.  相似文献   
9.
Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.  相似文献   
10.
Chapman  RM; Sutcliffe  SB 《Blood》1981,58(4):849-851
It has been reported by us and by others that after chemotherapy for Hodgkin's disease the ovary contains fewer than 5 primordial and primary follicles per 5 x 5 mm biopsy section. In young women this is associated with premature menopause. We report here that before treatment the tissue contains 18--55 such follicles per biopsy section. When women took combination oral contraceptives throughout the course of MVPP therapy, the posttreatment ovarian biopsy tissue had more than 20 follicles per histologic section. Normal menses were established in the five women who discontinued oral contraceptives at the end of MVPP therapy, and one of them is now pregnant.  相似文献   
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