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21.
CD40, a member of the tumor necrosis factor-alpha receptor family, is constitutively expressed by cells of hematopoietic and non- hematopoietic origin, including fibroblasts. Signaling through this receptor molecule regulates inflammatory cytokine secretion by many cell types. Based on the recently described cytokine secretory heterogeneity of fibroblast cell subsets, we hypothesized that secretion of inflammatory cytokines by gingival fibroblast cultures may be dictated by the existence of differential proportions of cytokine- secreting subpopulations which express high levels of CD40. After examining a large number of gingival fibroblast (GF) cultures we find that the frequency of IL-6- and IL-8-secreting cells mirrors the frequency of cells expressing high levels of CD40 in these cultures. In addition, we demonstrate a direct functional relationship between CD40 expression and IL-6 or IL-8 secretion by showing that ligation of this molecule on GF, and CD40+ fibroblast subsets in particular, up- regulates secretion of these cytokines in vitro.   相似文献   
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23.
How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
24.
Impaired expression of the FMR1 gene is responsible for the fragile X mental retardation syndrome. The FMR1 gene encodes a cytoplasmic protein with RNA-binding properties. Its complex alternative splicing leads to several isoforms, whose abundance and specific functions in the cell are not known. We have cloned in expression vectors, cDNAs corresponding to several isoforms. Western blot comparison of the pattern of endogenous FMR1 proteins with these transfected isoforms allowed the tentative identification of the major endogenous isoform as ISO 7 and of a minor band as an isoform lacking exon 14 sequences (ISO 6 or ISO 12), while some other isoforms (ISO 4, ISO 5) were not expressed at detectable levels. Surprisingly, in immunofluorescence studies, the transfected splice variants that exclude exon 14 sequences (and have alternate C-terminal regions) were shown to be nuclear. Such differential localisation was however not seen in subcellular fractionation studies. Analysis of various deletion mutants suggests the presence of a cytoplasmic retention domain encoded in exon 14 and of a nuclear association domain encoded within the first eight exons that appear however to lack a typical nuclear localisation signal.   相似文献   
25.
Human 19S IgM was digested with pronase and proteinase K. Proteolysis was relatively fast, producing Fab2 mu-like fragments (approx. mol. wt 114,000) and Fab mu-like fragments (approx. mol. wt 46,500) as major products. Immunochemical analysis indicated that the fragments produced by either enzyme are very similar and that they are produced by cleavage at the C mu 2-C mu 3 and C mu 1-C mu 2 domain junctions respectively. An intermediate species of mol. wt 74,300, immunologically identical to F(ab)2 mu, was also identified. This is thought to represent an F(ab)2 mu fragment with one Fab mu fragment removed. Fc mu-related fragments were not identified in the digestion mixture with either enzyme. Covalently linked and non-covalently linked 7S human IgM (IgMs and IgMr respectively) were digested with pronase and proteinase K. IgMs was degraded very rapidly by either enzyme, producing relatively stable F(ab)2 mu- and Fab mu-like fragments. These fragments were similar in mol. wt and immunochemical properties to those produced from 19S IgM. IgMr was also degraded rapidly by either enzyme, in this case producing Fab mu-like fragments with no detectable F(ab)2 mu-like fragments. The kinetics of digestion and nature of the products suggest that cleavage of 19S IgM by pronase or proteinase K proceeds via an initial attack at the C mu 2-C mu 3 junction, followed by further degradation at the Cmu 1-C mu 2 junction. The results obtained using 7S IgM show that the intersubunit disulphide bonds, and the associated pentameric structure, are responsible for the relative resistance of 19S IgM to proteolysis. The inter-heavy-chain disulphide bonds, in particular the bond at cys 337, are responsible for the limited susceptibility of F(ab)2 mu-like fragments to proteolysis.  相似文献   
26.
Female guinea pigs were treated daily with 1 mg of beta-estradiol-3-benzoate intramuscularly beginning 14 days before intravaginal inoculation with the chlamydial agent of guinea pig inclusion conjunctivitis and continuing during the course of the infection. Treatment with estradiol was found to markedly influence the course of genital infection with the chlamydial agent of guinea pig inclusion conjunctivitis, producing infections of greater intensity and longer duration than those in control animals. Moreover, pathogenesis was altered in that ascending infection was observed, resulting in endometritis, cystic salpingitis, and cystitis. Infection in the controls was limited to the cervix and vagina. Estradiol treatment increased the apparent number of infected cells in the cervix and vagina as detected by histopathology and immunofluorescent staining. Humoral and cell-mediated immune responses to the chlamydial agent of guinea pig inclusion conjunctivitis were comparable in estradiol-treated and untreated animals. These data indicate that hormonal manipulation may have profound effects on the course of chlamydial genital infections.  相似文献   
27.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
28.
易军  戴辉  张聚良 《医学争鸣》2000,21(5):86-86
0 引言 胰腺多房性潴留性囊肿极为罕见,我科收治1例,报道如下.1 病例报告 患者,男,29岁,因发现右上腹包块11d入院,缘于11d前无明显诱因感右上腹痛,仅局限于右上腹部,无肩背部放散痛,伴间歇性发热,体温最高达38.3℃,经抗炎,对症治疗无效.并逐渐可触及右上腹有一肿块,在当地医院行穿刺检查为脓血性液体.镜检发现炎性细胞,B超示:胆囊窝下方及右肾内侧及腹腔动脉,下腔静脉外前方可见异常区,大小约9.1cm×6.6cm×7.6cm,边界清楚,形态不规则,内呈蜂窝状,可见多个大小不等的液性暗区,CT示:右上腹部上腔静脉前方6.0cm×9.0cm肿块和周围组织粘…  相似文献   
29.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition  相似文献   
30.
With current trends in health consciousness, physicians are being asked to counsel individuals with chronic diseases who are involved in exercise programs. To accomplish this goal, health care providers should understand the effects of exercise on these individuals. Previously, epileptics were precluded from physical activity. Recent data reveals that exercise can be beneficial for epileptics. Therefore, in most cases, these individuals should be encouraged to participate in exercise programs. Asthmatics should be encouraged to participate in regular exercise to improve cardiovascular and respiratory fitness levels. For asthmatics, a proper exercise program can lead to an increased threshold before the stimulation of exercise-induced asthma occurs. The benefits of exercise for diabetics have been recognized for many decades. Exercise should be combined with appropriate diabetic education. Hypertrophic cardiomyopathy (HCM) is the number one cause of sudden death in young adults. HCM is a contraindication to strenuous exercise, but with proper medical management low-intensity exercise may be safely accomplished.  相似文献   
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