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991.
S Ichikawa  S Uchino  Y Hirata 《Lymphology》1989,22(3):123-131
We traced the origin of lymphatic capillaries of the chordae tendineae by serial ultrathin sections and electron microscopy of lymphatics identified first by light microscopy at the base of the chordae tendineae. Most of the lymphatics appear flattened in cross section, approximately 15 to 20 microns and 3 to 5 microns in greater and lesser diameters, respectively. Spiny (thorn-like) branchlets (about 10 microns in length) randomly projected from the sides of straight lymphatic capillaries and each was composed of a single endothelial cell with marginal zones in apposition to one another. The extreme end of a straight lymphatic capillary terminated blindly and consisted of a single endothelial cell with an ultrastructural appearance that resembled that of the spiny branchlets.  相似文献   
992.
Despite scientific advances, the therapeutic options for hepatitis C virus (HCV) are limited by poor response rates. HCV1b is particularly resistant to standard interferon therapy. The inhibition of the progression of chronic hepatitis and liver cirrhosis and the prevention of the occurrence and recurrence of hepatocellular carcinoma (HCC) are important and thus, there is a need for new therapeutic modalities for HCV1b infection. We, therefore, investigated highly immunogenic peptides and report in this study three novel candidate peptides (at positions 711-720 in envelope 2 protein, 885-893 in non-structural protein 2 and 1716-1724 in non-structural protein 4B) among 35 peptides of conserved regions of HCV1b proteins containing HLA-A24 binding motifs tested. Namely, HCV(711-720), HCV(885-893) and HCV(1716-1724) induced HLA-A24-restricted and peptide-specific cytotoxic T lymphocytes (CTLs) activity in peripheral blood mononuclear cells (PBMCs) from 7, 6 and 5 of 12 patients and also were recognized by plasma of 8, 5 and 7 of 12 HCV1b(+) patients, respectively. These results may provide new insight into the development of a peptide-based specific immunotherapy for HCV1b(+) HLA-A24(+) patients.  相似文献   
993.
To explore the mechanism of glomerular permselectivity defect in passive Heymann nephritis, an experimental model of human membranous glomerulopathy, Munich-Wistar rats were subjected to both micropuncture assessment of glomerular hemodynamics and whole kidney clearance measurements of graded size dextrans 10 days after injection of sheep anti-rat tubular antigen (anti-Fx1A). Compared with normal control rats, anti-Fx1A-treated animals were characterized by marked proteinuria (65 +/- 8 micrograms/min versus 6 +/- 1, p less than 0.001), markedly and significantly higher glomerular transcapillary hydraulic pressure difference (40 +/- 1 mm Hg versus 33 +/- 1, p less than 0.001), depressed ultrafiltration coefficient and impaired glomerular size-selective function as determined by fractional clearance of dextrans. Calculation of membrane parameters based on a recently defined heteroporous membrane model revealed abnormally high availability of non-size selective, large pore pathways in the glomerular capillary wall of the rats with passive Heymann nephritis. To ascertain the role of the altered hemodynamic pattern in the observed defect in the size-selective function of the glomerular capillary wall, glomerular transcapillary hydraulic pressure difference was manipulated experimentally in these proteinuric rats by intra-aortic infusion of acetylcholine or angiotensin II. These agents respectively suppressed and augmented glomerular transcapillary hydraulic pressure difference and brought about a decline of and a further rise in fractional clearance of larger dextrans along with parallel changes in both urine protein excretion rate and availability of nonselective channels. These results indicate that the permselectivity defect in passive Heymann nephritis is attributable, at least in part, to impaired size selectivity of the glomerular capillary wall caused by a prevailing abnormally high transcapillary hydraulic pressure difference.  相似文献   
994.
We reported a case of 64 year-old female patient of pulmonary tuberculosis associated with ARDS during corticosteroid treatment of Rheumatoid Arthritis. On admission her chief complaints were fever, fatigue and dyspnea. A chest roentgenogram showed diffuse alveolar infiltration consistent with pulmonary edema. Arterial blood gas studies showed severe hypoxemia. We clinically diagnosed so-called ARDS. Smears of sputum for acid fast bacilli were negative, but transbronchial lung brushing by bronchofiberscope revealed many acid fast bacilli. Intensive therapy with anti-tuberculosis drugs (INH, RFP, SM), high dose corticosteroid (methylprednisolone) therapy and mechanical ventilation was started. During the following 2 weeks, the PaO2 rose gradually and the alveolar infiltration on the chest roentgenogram disappeared. The experience of this case to emphasized the importance of suspecting this condition because pulmonary tuberculosis is a potentially curable cause of ARDS and it should also be emphasized that the good treatment effect could be expected with combined use of high dose corticosteroid and mechanical ventilation.  相似文献   
995.
OBJECTIVE: To clarify the mechanism of impaired bone formation during low dose methotrexate (MTX) therapy. METHODS: The in vitro effects of MTX on the function and differentiation of osteoblastic cells were investigated using (1) a mouse osteogenic cell line (MC3T3-E1) with the capacity to differentiate into osteoblastic or osteocytes, (2) a human osteoblastic osteosarcoma cell line (SaOS-2) with a mature osteoblastic phenotype, and (3) mouse bone marrow stromal cells containing osteoblast precursors. Osteoblast function was assessed by measuring the cellular activity of alkaline phosphatase (ALP) and the mineralization capacity of cultures. RESULTS: MTX suppressed ALP activity dose-dependently in growing MC3T3-E1 cells, but proliferation of these cells was only inhibited by a high concentration of MTX. In contrast, inhibition of ALP activity in MC3T3-E1 cells of mature osteoblastic phenotype was only observed with 10(-8) M and 10(-7) M MTX, and proliferation was not influenced. ALP activity and the proliferation of SaOS-2 cells were not inhibited by MTX, even when growing cells were treated. However, both ALP activity and formation of calcified nodules in bone marrow stromal cell cultures were significantly suppressed by MTX at concentrations between l0(-10) and 10(-7) M. CONCLUSION: These results suggest that MTX suppresses bone formation by inhibiting the differentiation of early osteoblastic cells.  相似文献   
996.
The purpose of this study was to compare biochemical markers of bone resorption and formation in young women using different hormonal contraceptive methods. Women aged 18-39 yr who were using depot medroxyprogesterone acetate (DMPA) contraception were recruited for the study; comparison women were matched by age and clinic location. There were 116 women using DMPA, 39 using oral contraceptives containing estrogen and progestin, and 72 not currently using hormonal contraceptives. Biochemical measurements were serum calcium, PTH and osteocalcin, and urine N-telopeptide. Bone density was measured using dual-energy x-ray absorptiometry. The N-telopeptide levels, adjusted for age and other risk factors, were 42.4 +/- 2.3 nmol/mmol creatinine in the DMPA group, 26.2 +/- 3.3 nmol/mmol in the oral contraceptive group, and 35.4 +/- 2.9 nmol/mmol in the nonusers; significant differences were seen in all pairwise comparisons. Osteocalcin levels showed the same pattern, although the difference between the DMPA users and nonusers was not statistically significant. There were no differences among groups in the PTH levels. The bone density at the spine was 1.086 +/- 0.085 g/cm(2) in the DMPA group, 1.103 +/- 0.095 g/cm(2) in the oral contraceptive group, and 1.093 +/- 0.090 g/cm(2) in nonusers (P = 0.051). The results suggest that in women using DMPA bone resorption exceeded bone formation.  相似文献   
997.
Many people living with HIV/AIDS (PHA) use herbal medicine as one of alternative therapies, where curative options are limited. This study aimed to examine the association between the herbal medicine use and quality of life (QOL) among PHA in northeastern Thailand. Participants were 132 HIV-positive Thai adults who attended the PHA's self-help group meetings from June to July 2002. Health-related QOL scores were measured by self-administered questionnaire from the Medical Outcomes Study-HIV Health Survey. Dimensions of physical function (PF) and mental health (MH) in QOL were assessed. Additional data were collected on herbal medicine use, socio-demographic, psychosocial and HIV-related characteristics. The herbal medicine users had significantly better MH scores than the non-users, while the herbal medicine use was not statistically associated with PF scores. When stratified, herbal medicine users with the following characteristics had significantly better MH scores than the non-users: female, widowed, having no income, reporting any HIV-related symptom, having no instrumental support or receiving subsidies. In conclusion, herbal medicine use was associated with better MH especially among socially vulnerable PHA. This study suggests that herbal medicine has a potential to improve the MH aspect of QOL among socially vulnerable PHA who cannot easily receive antiretroviral therapy in Thailand.  相似文献   
998.
We describe two patients with anti-BP180-type mucous membrane pemphigoid (MMP), who were correctly diagnosed and treated in early stages through the cooperation of dentists and dermatologists. Patient 1 was a 74-year-old woman who visited our dental department due to blisters over the oral mucosa and eruptions on the skin. She had also experienced bleeding of the gingiva and palate mucosa. Biopsy specimens from the oral mucosa revealed detachment of epithelial basement membrane and subepithelial lamina propria with slight chronic inflammation. Direct immunofluorescence (DIF) revealed linear IgG and IgA deposits along the basement membrane zone (BMZ). Indirect immunofluorescence (IIF) using 1 M-NaCl split normal human skin showed binding of IgG and IgA on the epidermal side. On immunoblot analysis, IgG and IgA autoantibodies reacted with the C-terminal protein of BP180. These findings indicated a diagnosis of anti-BP180-type MMP. Patient 2 was a 59-year-old woman who was referred to our dental department with a history of blisters and large erosions on the gingiva. Biopsy specimens from the oral mucosa revealed partial junctional separation at the level of the basement membrane. DIF showed linear depositions of IgG and C3 along the BMZ. IIF, using 1 M-NaCl split normal human skin, revealed circulating anti-BMZ-IgG antibodies bound to the epidermal side. These findings indicated a diagnosis of anti-BP180-type MMP. Both patients were treated successfully with systemic or topical steroids and oral health care. In conclusion, appropriate clinical examination and cooperation among medical specialists are important for the early diagnosis and treatment of patients with recurrent and chronic stomatitis and for their good prognosis.  相似文献   
999.
OBJECTIVES: We aimed to determine the effects of macrophage colony-stimulating factor (M-CSF) and granulocyte colony-stimulating factor (G-CSF) treatment on both the repair process and ventricular function after myocardial infarction (MI). BACKGROUND: The M-CSF and G-CSF have multiple potential effects on cells involved in wound repair. METHODS: Myocardial infarction was induced by 45- or 90-min coronary occlusion and reperfusion in rats with or without subsequent injection of M-CSF (10(6) IU/kg/day) or G-CSF (50 microg/kg/day) for five days. We examined histology and messenger ribonucleic acid (mRNA), and assessed left ventricular function in situ using a conductance catheter. RESULTS: Five days after MI, M-CSF increased the number of ED-1-positive cells, mRNA levels of transforming growth factor-beta-1, collagen I and III, and collagen fibers within the infarct. Fourteen days after MI, induced by 45-min ischemia, left ventricular end-systolic elastance (Ees) was reduced (1,191 +/- 87 mm Hg/ml vs. 1,812 +/- 150 mm Hg/ml) and both isovolumic relaxation time constant (tau) (11.9 +/- 0.9 ms vs. 8.5 +/- 0.4 ms) and left ventricular end-diastolic volume (LVEDV) (0.225 +/- 0.014 ml vs. 0.172 +/- 0.011 ml) increased versus sham-operated rats. These alterations after MI were attenuated by M-CSF (Ees = 1,650 +/- 146, tau = 9.7 +/- 0.7, LVEDV = 0.199 +/- 0.012) but not by G-CSF. This beneficial effect of M-CSF on Ees was also detected in hearts with MI induced by 90-min ischemia. Furthermore, M-CSF increased collagen content within infarcts and reduced the proportion of thin collagen fibers 14 days after MI. The Ees significantly correlated with infarct collagen content. Nevertheless, neither M-CSF nor G-CSF modified infarct size. CONCLUSIONS: The M-CSF treatment attenuates deterioration of left ventricular function after MI by accelerating infarct repair.  相似文献   
1000.
Using 3-color flow cytometry, we determined the proportions of activated T cells (DR+), including CD4+ cells, CD8+ cells, and their subsets, in the peripheral blood of 17 patients with Sj?gren's syndrome (SS). Activated T cells were significantly increased in CD4+ cells, CD8+ cells, and T suppressor inducer (CD4+, Leu-8+), T helper (CD4+, Leu-8-), and T cytotoxic (CD8+, CD11-) subsets, but not the T suppressor/natural killer subset (CD8+, CD11+), in patients with SS as compared with the controls. Furthermore, the proportions of activated T cells in the CD4+, Leu-8- subset, the CD8+ subset, or the CD8+, CD11- subset showed a positive correlation with serum gamma globulin levels in the SS patients. Our findings suggest that a certain immunoregulatory balance between T helper and T suppressor activities is maintained in SS patients, although this balance seems to occur at highly activated levels, and that quantitative changes of some lymphocyte subsets are important factors in maintaining this balance. We discuss the possibility that CD4+, Leu-8+ cells recirculate into peripheral lymph nodes, while CD4+, Leu-8- cells migrate into inflammatory tissues such as salivary glands, since the Leu-8 antigen is reported to be a homing receptor in peripheral lymph nodes. This process might be accelerated in SS, and each T cell subset may further participate in immunologic activation in the lymph nodes or target tissues.  相似文献   
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