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101.
T cell immune response c-DNA (TIRC7) is up-regulated during the early stages of T-cell activation in response to alloantigens. In this study, we analyzed the effects of newly developed monoclonal antibodies (mAb) against TIRC7 in acute cardiac allograft rejection. Fully vascularized heterotopic allogeneic heart transplantation was performed in mice across a full-mismatch barrier (C57Bl/10 into CBA). Recipients received seven injections (day 0-7) of a novel anti-TIRC7 mAb or remained untreated. Graft survival, histology and ex vivo lymphocyte functions were tested. Targeting of TIRC7 with an anti-TIRC7 mAb diminishes lymphocyte infiltration into grafts resulting in delay of morphological graft damage and prolongation of allograft survival. The lymphocytes from anti-TIRC7 mAb-treated animals exhibit hypo-responsiveness without evidence of lymphocyte depletion against the donor allo-antigens. Proliferation and expression of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) were down-regulated while interleukin-4 (IL-4) and IL-10 expression were spared. Moreover, anti-TIRC7 mAb enhanced up-regulation of CTLA-4 expression but suppressed up-regulation of CD25 on stimulated lymphocytes in vitro and in vivo. Ligation of TIRC7 has important effects on the regulation of co-stimulatory signaling pathways associated with suppressing of T-cell activation. Targeting of TIRC7 may therefore provide a novel therapeutic approach for modulating T cell immune responses during organ transplantation.  相似文献   
102.
目的:调查没有临床神经损害体征的2型糖尿病患者早期的高级神经功能改变,方法:分别对52例2型糖尿病患者和32名健康对照者进行了韦氏智力量表的相似、数字广度、数字符号、木块图等4项分测验测定,采用二合一(相似、木块图)的方法计算简式智商,同时进行事件相关电位检查,结果:糖尿病患者组的相似、木块图分测验成绩和简式智商明显较健康对照组低下,ERP检查发现病人组N2、P3潜伏期较对照组明显延长,结论:2型糖尿病可导致高级神经功能损害。并且这种损害可能要早于周围神经损害。  相似文献   
103.
Smoking delays the healing process and increases morbidity associated with many common musculoskeletal disorders, including long bone fracture. In the current study, a murine model of tibial fracture healing was used to test the hypothesis that smoking delays chondrogenesis after fracture. Mice were divided into two groups, a nonsmoking control group and a group exposed to cigarette smoke for 1 month prior to surgical tibial fracture. Mice were euthanized at 7, 14, and 28 days after surgery. The outcomes measured were immunohistochemical staining for type II collagen protein expression as a marker of cartilage matrix and proliferating cell nuclear antigen (PCNA) staining to measure proliferation at the site of injury. Toluidine blue staining and histomorphometry were used to quantify areas of cartilaginous and noncartilaginous fracture callus. Radiographs were analyzed for evidence of remodeling after injury. At day 7 after injury, mice exposed to cigarette smoke had a smaller fracture callus with less cartilage matrix compared to controls. Proliferation was present at high levels in both groups at this time point, but proliferating cells had a more immature morphology in the smoking group. At day 14, chondrogenesis was more active in smokers compared to controls, while a higher percentage of bone was present in the control animals. At day 28, X-ray analysis revealed a larger fracture callus remaining in the smoking animals. Together, these findings show that the chondrogenic phase of tibial fracture healing is delayed by smoking. This study represents, to our knowledge, the first analysis of molecular and cellular mechanisms of healing in a smoking mouse fracture model.  相似文献   
104.
BACKGROUND: Recent reports have shown a correlation between extensive Mongolian spots and mucopolysaccharidosis type II (Hunter syndrome). However, a statistical survey of the incidence and natural history of extensive Mongolian spots among the patients with Hunter syndrome is lacking. OBJECTIVES: To determine the prevalence of extensive Mongolian spots, to determine the natural course of the spots according to age in Japanese patients with Hunter syndrome, and to compare them with the results obtained from the patients' brothers who did not have Hunter syndrome. PATIENTS/METHODS: Fifty-two males with Hunter syndrome aged 3 to 40 years were studied. Twenty-five patients were examined in two clinics to determine the existence and characteristics of the spots. We interviewed their families about the spots in their neonates and the natural course of the spots according to their ages. The same survey was done among another 27 patients using a mailed questionnaire to their families. As control, we investigated 21 brothers of the patients by a mailed questionnaire to their families. RESULTS: The extensive Mongolian spots are identified in almost all the infants with Hunter syndrome and disappear extremely later in their life. The lesions had a high incidence of deep-blue hyperpigmentation. Regardless of age, the overall incidence was 78%. All of the brothers who did not have Hunter syndrome had common-type Mongolian spots in neonates, which regressed during their childhood. CONCLUSION: Our results confirm a strong correlation between extensive Mongolian spots and Hunter syndrome for the Japanese population. The presence of extensive Mongolian blue spots should alert the physician to the possibility of Hunter syndrome.  相似文献   
105.
Summary: Clinical studies revealed that angiotensin converting enzyme (ACE) inhibitor reduces proteinuria and attenuates progressive decline in renal function in IgA nephropathy. Recent studies by us and others have demonstrated that the homozygote of the D allele (DD) of the ACE insertion/deletion (I/D) polymorphism is a potential risk factor for poor prognosis in IgA nephropathy, and that this deletion polymorphism predicts the therapeutic efficacy of ACE inhibition on proteinuria and, potentially, on progressive deterioration of renal function in patients with the nephropathy.  相似文献   
106.
报告5例对胰岛素抵抗的糖尿病特殊类型病例,其均具有胰岛素应用指征,但使用胰岛素后血糖却反而上升,逐渐增加胰岛素用量,则血糖值亦呈上升趋势。对该类病人的治疗,首先停用胰岛素,改用自制中药制剂及优降糖、降糖灵治疗,取得了良好效果。  相似文献   
107.
Clinicopathologlc and mucin histochemical characteristics of 90 cases of ovarian mucinous borderline tumors (MBT) of Intestinal (IMET) and müllerian types (MMBT) were studied to determine whether IMBT and MMBT constitute distinct tumor subtypes. The IMBT (77 cases, 78 lesions) contained goblet cells, absorptive cells and endocrine cells, which represented Intestinal differentiation. The average diameter of IMBT was 13.4 cm. Five patients (6.5%) had stage III disease wtth pseudomyxoma perltonel and one of them died from tumor. Approximately 50% of IMBT demonstrated gastrointestinal characteistics on mucin histochemistry. The MMBT (13 cases, 14 lesions) consisted of mumus columnar cells and eosinophilic cells, with no Intestinal differentiation. MMBT accounted for 15.2% of MBT. MMBT averaged 8.4 cm in diameter, and 29% were associated with endometriosls of the ipsilateral ovary. All patients with MMBT had stage I disease, and none suffered from pseudomyxoma peritonel. All patients whose follow-up data were available were alive and well, without evidence of tumor recurrence. The mucin histochemical findings in MMBT resembled those of noml endocervix. Results of the present study suggest that IMBT and MMBT have different characteristics and constitute distinct subtypes of MBT.  相似文献   
108.
Design of a Centrifugal Blood Pump with Magnetic Suspension   总被引:1,自引:0,他引:1  
Abstract: A new concept blood pump, whose impeller is suspended by permanent magnets and a mechanical pivot without seals or ball bearings, is presented in this paper. The primary aim of the blood pump is an application to implantable artificial hearts. The prototype model is of a centrifugal type with a four-vaned semiopen impeller 50 mm in diameter. Since this mechanism has no seals or ball bearings, flow stagnation or heat generation that might cause blood cell denaturation is expected to be small. The results of performance testing for the prototype model 2 were satisfactory regarding pump head and efficiency. The radial-suspension magnets and the magnetic coupling were stable. As a result, the present mechanism has been verified to be a candidate applicable to implantable artificial hearts.  相似文献   
109.
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality.  相似文献   
110.
对114例不同类型和级别的结肠癌进行银染核仁形成区嗜银蛋白(Ag-NORs)形态定量研究.结果表明,Ag-NORs数量、大小和分布在结肠未分化癌和印戒细胞癌组与管状腺癌和粘液腺癌组比较,有明显差异.管状腺癌随分化程度的降低,Ag-NORs的数量、形态、大小和分布也发生等级性变化.结果提示,Ag-NORs形态定量的数量、形态、大小和分布4项指标对结肠癌分型有一定意义,对管状腺癌分级有较好的诊断价值。  相似文献   
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