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51.
We have previously reported 2 cases of healthy men showing in vivo monoclonal expansion of mature CD4? CD8? αβ T cells. In the present study, an additional 3 adults were found to exhibit such an expansion, among a total 464 adult donors studied. These 5 individuals were otherwise physiologically normal, with no history of severe illness and autoimmune disease at the time of examination. To investigate the mechanisms of the clonal expansion, further characterization of the clonal cells was attempted. No apparent preference for usage of the Tcell receptor β chain variable region was observed in the clonal T cells. These clonal T cells showed lectin-dependent or redirected antibody-dependent cell-mediated cytotoxicities, whereas they could not lyse autologous lymphoblastoid cell lines. Failure of Fas antigen expression was not observed for any of these clones. These results suggest that clonal expansion of CD4? CD8? αβ T cells frequently occurs in the periphery without any T cell abnormalities.  相似文献   
52.
To examine the roles of cytokines in muscle regeneration, we injected cardiotoxin into mouse tibialis anterior muscle and examined the expression profiles of cytokines and related genes in the regeneration process. Expression of 40, 64, and 7 genes among 522 genes spotted on a cytokine expression array were increased more than fivefold at 48 hours, 96 hours, and 7 days after toxin injection, respectively, when compared with those of the control muscle. Especially the levels of mRNA for chemokines and chemokine receptors, many of which are potent regulators of macrophages, were highly elevated 48 hours after injury. The expression of osteopontin (OPN), a versatile regulator of inflammation and tissue repair, was up-regulated more than 118-fold in regenerating muscle at 48 hours after injury. Northern blotting confirmed that the expression of OPN was highest at 48 hours after cardiotoxin injection and declined sharply thereafter. Immunohistochemistry showed that OPN was detected both in the cytoplasm of macrophages and in necrotic muscle infiltrated with macrophages. Our studies suggest OPN may serve as an adhesion molecule that promotes macrophage binding to necrotic fibers and may be an important mediator in the early phase of muscle regeneration.  相似文献   
53.
Blood concentrations of 14C-rokitamycin (14C-TMS-19-Q) reached their peaks at 1 hour after a single oral (200 mg/kg) administration to male and female rats, and they were 28.0 +/- 0.8 and 24.9 +/- 2.0 micrograms/ml, respectively. No significant differences were observed between male and female in AUC values or maximum blood concentrations. The distribution of TMS-19-Q was good, and concentrations of 14C were high in liver, kidney, spleen, pancreas, adrenal, pituitary gland, thyroid, trachea, exorbital lacrimal gland, submaxillary gland and bone marrow. During the 72 hours period after a single oral (200 mg/kg) administration of 14C-TMS-19-Q to male rats, 8.0 and 89.6% of the dose were excreted in urine and feces, respectively and a total recovery rate was 97.5% of the dose. During the 48 hours period after a single intraduodenal (200 mg/kg) administration of 14C-TMS-19-Q in male rats, 6.9 and 36.2% of the dose were excreted in urine and bile, respectively. Reabsorption of 14C excreted from the bile was negligible. Absorptions of TMS-19-Q from the duodenum, jejunum, ileum and colon were good, but absorption from the stomach was negligible. Major metabolic reactions of TMS-19-Q were deacylation and hydroxylation, and the major metabolites in rats of TMS-19-Q found in the plasma, urine and bile after oral and intraduodenal administration were 10"-OH-TMS-19-Q, leucomycin A7, leucomycin V and 14-OH-leucomycin V.  相似文献   
54.
Interactions of rat ascites hepatoma cells with primary cultured layers of rat mesentery-derived cells were studied. The mesentery-derived cells were isolated from rat mesentery and cultured in Eagle's minimum essential medium with a 2-fold concentration of amino acids and vitamins supplemented with 10% calf serum. The primary cultured cells, consisting mainly of mesothelial cells in polygonal shape, forms a "paving stone" sheet. Upon seeding the tumor cells on the mesentery-derived cell layers, three different types of tumor cell growth were observed. Type 1 was the formation of piled-up tumor cell nests on mesothelial cell layers. Type 2 was the formation of flattened tumor cell islands underneath mesothelial cell layers. This island formation was clearly observed under a phase contrast microscope 2 days after the tumor cell seeding. Protrusion of cellular processes of the tumor cells beneath mesothelial cells was occasionally seen. Type 3 was the growth of tumor cells in suspension. These types of tumor cell growth closely resemble those in the peritoneal cavity observed after i.p. implantation of the tumor cells. When the tumor cells recovered from the blood of tumor-bearing rats were seeded, flattened tumor cell islands were formed 15 times more frequently than when the tumor cells isolated from host peritoneal cavity were seeded. Shortly after the appearance of small flattened tumor cell islands, a distinct morphological change of mesothelial cells from polygonal to spindle shape was seen preferentially at the marginal area of the cell layers (a partial retraction of cell edges). The retraction of mesothelial cells was induced not only by seeding the tumor cells but by adding the tumor ascites fluid or the medium conditioned by the tumor cell culture. The morphological change was reversed by changing the culture medium to remove the effectors. These results indicate that the system described in this study can provide a useful model to study tumor cell invasion.  相似文献   
55.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
56.
ObjectiveTo assess the implementation of the Regional framework for action on implementation of the End TB Strategy in the Western Pacific, 2016–2020 in countries and areas in the World Health Organization Western Pacific Region.MethodsWe used a mixed methods approach to assess the framework’s measurable and perceived impact. We conducted an analysis of national tuberculosis strategic plans, a cross-sectional survey of senior staff of tuberculosis programmes, key informant interviews and some country case studies.FindingsOf the 37 countries and areas of the Western Pacific Region, 14 had a national tuberculosis strategic plan, including all countries and areas with a high incidence of tuberculosis. Most senior tuberculosis programme staff who responded to the survey (16/23) found the regional framework useful when developing their national targets and grant applications. Programmatic challenges identified included financing, human resources, public–private mix, active case finding, and paediatric and drug-resistant tuberculosis. Most of the 17 key informants thought that the regional framework’s categorization of actions (for all settings, for specific settings and for pre-elimination settings) was useful, but that the added value of the regional framework over other relevant documents was not obvious because of overlap in content.ConclusionThe regional framework influenced national level tuberculosis control planning and implementation in a positive way. A future regional framework should provide a longer-term strategic horizon and specifically address emerging trends and persistent problems faced by countries or areas of the region.  相似文献   
57.
One hundred patients with carcinoma of the urinary bladder were treated with preoperative intra-arterial anticancer drug infusion in combination with an active carbon-based artificial liver or preoperative radiotherapy (400 rad X 5 days, total 2000 rad) in order to alleviate systemic side effects after preoperative adjuvant therapy and to perform radical cystectomy as soon as possible. Five-year survival was 69.8% in the artificial liver combined preoperative intra-arterial anticancer drug infusion group, and that of the no-pretreatment group and the preoperative irradiated group was 48.6% and 45.8%, respectively. In particular, the CDDP treated group had a higher 5-year survival of 77.4% than did the without CDDP treated group. This was attributable mostly to improved prognosis of T2, whereas either of these preoperative adjuvant therapies failed to ameliorate the prognosis of T3 or T4 stage patients. Therefore, systemic preoperative anticancer chemotherapies such as M-VAC are necessary to destroy "micrometastases" and to improve the prognosis of highly advanced bladder cancer.  相似文献   
58.
Journal of Artificial Organs - Few reports have examined the association between changes in cerebral oxygenation and clinical factors, including blood pressure (BP), upon standing after...  相似文献   
59.
A 58-year-old man was found to have a basaloid carcinoma of the thymus, initially detected as an abnormal shadow on chest radiograph. The patient underwent resection followed by radiotherapy, and has survived 25 months without recurrence. Although this rare tumor may be related to multilocular thymic cyst, its pathogenesis is obscure. We discuss clinicopathologic features of our case and others.  相似文献   
60.
We report a successful surgical case of billowing mitral leaflet syndrome combined with severe mitral regurgitation. A 45-year-old man suffered from congestive heart failure and admitted our institution for precise examination. A heart murmur was pointed out by a medical examination at his high school, and mitral valve prolapse was detected by echocardiography at 23 year of age. No medication was applied because he showed no symptom. From 44 year of age, he noted palpitation on exercise. Holter monitor showed blocked PAC and Wenckebach A-V block, and transesophageal echocardiography indicated severe mitral regurgitation due to the billowing of voluminous both leaflets. At his operation, we recognized the billowing of both leaflets with torn chordae, and size of the mitral valve orifice was 8.5 x 5 cm. The huge mitral valve was replaced with a CarboMedics 31M prosthetic valve by plicating mattress stitches of native mitral annulus. Histopathologic findings showed accumulation of acid mucopolysaccharide. Postoperative echocardiography showed reduction of the left ventricular volume and preservation of the left ventricular function. Relatively slow progression of the billowing mitral leaflet syndrome did not cause apparent symptoms of heart failure in this patient. Therefore, proper selection of the procedure and timing of surgical treatments might be important for successful long-term results after operation of the billowing mitral leaflet syndrome.  相似文献   
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