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71.
Kirschbaum  NE; Gumina  RJ; Newman  PJ 《Blood》1994,84(12):4028-4037
Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell-cell adhesion molecule that is expressed on circulating platelets, on leukocytes, and at the intercellular junctions of vascular endothelial cells and mediates the interactions of these cells during the process of transendothelial cell migration. The cDNA for PECAM-1 encodes an open reading frame of 738 amino acids (aa) that is organized into a 27- aa signal peptide, a 574-aa extracellular domain composed of 6 Ig homology units, and a relatively long cytoplasmic tail of 118 aa containing multiple sites for posttranslational modification and postreceptor signal transduction. To provide a molecular basis for the precise evaluation of the structure and function of this transmembrane glycoprotein, we have determined the organization of the human PECAM-1 gene. The PECAM-1 gene, which has been localized to human chromosome 17, is a single-copy gene of approximately 65 kb in length and is broken into 16 exons by introns ranging in size from 86 to greater than 12,000 bp in length. Typical of other members of the Ig superfamily, each of the extracellular Ig homology domains is encoded by a separate exon, consistent with PECAM-1 having arisen by gene duplication and exon shuffling of ancestral Ig superfamily genes. However, the cytoplasmic domain was found to be surprisingly complex, being encoded by seven short exons that may represent discrete functional entities. Alternative splicing of the cytoplasmic tail appears to generate multiple PECAM-1 isoforms that may regulate phosphorylation, cytoskeletal association, and affinity modulation of the mature protein. Finally, a processed pseudogene having 76% identity with PECAM- 1 cDNA was identified and localized to human chromosome 3. These findings should have important implications for structure/function analysis of PECAM-1 and its role in vascular adhesive interactions.  相似文献   
72.
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain.  相似文献   
73.
Epstein-Barr virus (EBV) is the cause of infectious mononucleosis and is associated with a variety of life-threatening diseases in humans. Therefore the development of an effective vaccine is an important objective. Many of the initial studies of vaccine efficacy analyse the ability of vaccine preparations to prevent the induction of lymphomas in cottontop tamarins by the B95-8 strain of EBV. We used a vaccinia virus recombinant expressing gp340, vMA1, tested previously in the cotton-top tamarin, to evaluate a common marmoset model in which the challenge virus, M81, resembles more closely the wild-type strains of EBV in the general population than does the standard B95-8 strain. We characterised the M81 strain of EBV with respect to the sequence of its gp340/220 gene and in regard to the presence of a region deleted in B95-8. Replication of the challenge virus in the group vaccinated with vMA1 was decreased when compared to control groups. © 1996 Wiley-Liss, Inc.  相似文献   
74.
Researchers have reported similar prevalence rates for non-suicidal self-injury (NSSI) among men and women, yet few studies have investigated gender differences in NSSI. This study describes and compares basic NSSI characteristics among a nonclinical sample by gender. Forty-eight individuals reporting a history of NSSI were interviewed (M = 18.52 years old, SD = 1.18 years). NSSI characteristics, including frequency, age of onset, method of NSSI, pain and control during NSSI, and degree of medical injury were compared between men (n = 19) and women (n = 29). Men and women differed significantly on age of onset, degree of medical injury, and NSSI methods. This study supports previous findings of gender differences in NSSI and suggests that further investigation of gender differences in NSSI is warranted.  相似文献   
75.
76.
Studies of the role of individual genes in chronic lymphocytic leukemia (CLL) have been hampered by the inability to consistently transfect primary tumor cells. Here, we describe a highly efficient method of genetically modifying primary CLL cells using a VSVG pseudotyped lentiviral vector. We transduced CD38 negative CLL cells with a lentiviral vector encoding CD38 which caused increased surface CD38 expression in all the samples tested (n=17) with no evidence of plasmacytoid differentiation. The mean percentage of positive cells expressing CD38 was 87%±8.5% and the mean cell viability 74%±17%. This high level of transduction of all the CLL cell samples tested demonstrates the utility of this technique which should prove applicable for the introduction and analysis of other genes in these non-dividing cells.  相似文献   
77.
The Interpersonal Theory of Depression suggests that depressed individuals have behavioral patterns that alienate people in their environment, thereby reducing social support and maintaining their depression. Excessive reassurance seeking has been implicated as such a behavior. A model was tested in which excessive reassurance seeking mediates the relationships between sociotropy and increases in negative interpersonal life events as well as sociotropy and depressive symptoms. Participants consisted of 110 undergraduate students. Measures were given at two time points 6 weeks apart assessing sociotropy, excessive reassurance seeking, negative interpersonal life events, and depressive symptoms. Results suggested that excessive reassurance seeking mediated the predicted relationship between sociotropy and negative interpersonal life events, but did not mediate the relationship between sociotropy and depressive symptoms. The implications for these findings in the interactional nature of depression are discussed.  相似文献   
78.
Effect of lung-volume-reduction surgery in patients with severe emphysema   总被引:17,自引:0,他引:17  
BACKGROUND: Although many patients with severe emphysema have undergone lung-volume-reduction surgery, the benefits are uncertain. We conducted a randomized, controlled trial of the surgery in patients with emphysema. Patients with isolated bullae were excluded because such patients are known to improve after bullectomy. METHODS: Potentially eligible patients were given intensive medical treatment and completed a smoking-cessation program and a six-week outpatient rehabilitation program before random assignment to surgery or continued medical treatment. After 15 patients had been randomized, the entry criteria were modified to exclude patients with a carbon monoxide gas-transfer value less than 30 percent of the predicted value or a shuttle-walking distance of less than 150 m, because of the deaths of 5 such patients (3 treated surgically and 2 treated medically). RESULTS: Of the 174 subjects who were initially assessed, 24 were randomly assigned to continued medical treatment and 24 to surgery. At base line in both groups, the median forced expiratory volume in one second (FEV1) was 0.75 liter, and the median shuttle-walking distance was 215 m. Five patients in the surgical group (21 percent) and three patients in the medical group (12 percent) died (P=0.43). After six months, the median FEV1 had increased by 70 ml in the surgical group and decreased by 80 ml in the medical group (P=0.02). The median shuttle-walking distance increased by 50 m in the surgical group and decreased by 20 m in the medical group (P=0.02). There were similar changes on a quality-of-life scale and similar changes at 12 months of follow-up. Five of the 19 surviving patients in the surgical group had no benefit from the treatment. CONCLUSIONS: In selected patients with severe emphysema, lung-volume-reduction surgery can improve FEV1, walking distance, and quality of life. Whether it reduces mortality is uncertain.  相似文献   
79.
Ovarian hyperandrogenism is a common disorder of women of reproductive age. The therapies that are presently available to treat this disorder are not uniformly effective or free of adverse effects. We conducted a prospective study of eight women receiving ketoconazole for a mean duration of 44 +/- 15 (SEM) weeks, as therapy of ovarian hyperandrogenism. Serum testosterone and hair growth rate declined in patients while on 600 to 1,000 mg ketoconazole daily. Menses normalized in seven of eight subjects during treatment. Ketoconazole therapy was not associated with a change in basal or postgonadotropin-releasing hormone stimulation gonadotropin levels. Basal cortisol levels were also unchanged on ketoconazole though responsiveness of cortisol to adrenocorticotropic hormone stimulation tended to be reduced. We conclude that ketoconazole can effectively reverse the biochemical and clinical abnormalities of ovarian hyperandrogenism. Until the issue of its safety is resolved, ketoconazole therapy is best limited to select individuals who agree to careful monitoring and the use of reliable birth control methods during treatment.  相似文献   
80.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described.  相似文献   
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