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91.
The effectiveness of the clinical pathway for laparoscopic cholecystectomy was evaluated, and the efficiency of medical care was analyzed. The duration of hospitalization and the number of National Health Insurance (NHI) points for medical service fees were compared between 86 patients treated after introduction of the clinical pathway (pathway group) and 56 patients treated before introduction of the clinical pathway (pre-pathway group). In the pathway group, variance from the pathway occurred in 24 patients (27.9%) due to postponement of discharge in 7 patients, to earlier discharge in 5 patients, and to insertion of a bile duct catheter in 5 patients. Total and postoperative hospitalization times were significantly shorter in the pathway group than in the pre-pathway group (8.0 +/- 1.6 vs 13.7 +/- 9.0 days, p<0.0001, 5.4 +/- 1.1 vs 6.5 +/- 2.2 days, p<0.0001, respectively). In the pathway group, the total number of NHI points was lower and the number of points per day was higher. By simulation, the total number of NHI points for the 5-day pathway (discharge on postoperative day 3 or earlier) was significantly lower than that for the current 7-day pathway. Moreover, the weekly profit per bed with the 3-day pathway (discharge on postoperative day 1) was more than twice that with the current pathway. The results suggest that the clinical pathway for laparoscopic cholecystectomy is beneficial for patients and useful for the introduction of diagnosis procedure combination in our hospital.  相似文献   
92.
Previously we reported disease-specific interaction between interferon- (IFN-) and interleukin-4 (IL-4) in patients with IgA nephropathy (IgAN), suggesting the existence of unusual T cell behavior in this disease. In the present study, we investigated characteristic synthesis of interferon- (IFN-) and expression of IFN- receptor (IFN-R) in the peripheral blood mononuclear cells (PBMC) from patients with IgAN and other chronic proliferative glomerulonephritis (PGN). Heparinized peripheral blood samples were obtained from 38 patients with chronic mesangial proliferative glomerulonephritis (CGN; including 24 with IgA nephropathy) and 20 healthy controls. PBMC were isolated by gradient centrifugation and fragments were cultured in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% fetal calf serum (FCS) for 72 hr. IFN- concentrations in supernatants were evaluated by the enzyme-linked immunosorbent assay (ELISA). Other parts of PBMC pellets were reacted with anti-human IFN-R monoclonal antibody and FITC-labeled anti-mouse second antibody for analysis of IFN-R expression on these cells by FACScan. The remaining PBMC were fractionated into CD4+ T cells, CD8+ T cells, B cells, NK, cells and macrophages using the MACS cell sorting system. The isolated cells were evaluated for IFN- or IFN-R mRNA expression by the semiquantitative RT-PCR method.In vitro IFN- synthesis was enhanced in patients with CGN, and NK cells were revealed to be responsible for such enhancement. On the other hand, the expression of IFN-R on macrophages was suppressed in CGN patients. These results suggest that impairment of regulation of the IFN- system might be involved in the development of CGN.  相似文献   
93.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
94.
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis.  相似文献   
95.
The etiology of usual interstitial pneumonia (UIP), a progressive lung disease, remains unclear. We examined alveolar structure in UIP three-dimensionally. Lung biopsy specimens from five patients with idiopathic pulmonary fibrosis were used. Sections 150-microm thick were stained with elastica solution for elastic fibers, with alpha-smooth muscle actin antibody for myofibroblasts, with anti-Thomsen-Friedenreich antibody for type-II pneumocytes and with anti-CD34 antibody for blood vessels. We examined them three-dimensionally using a laser confocal microscope or light microscope. In the fibrotic lesions, the thick elastic fibers forming the alveolar framework were not particularly dense considering the reduction in alveolar volume. Near the fibrotic lesions, some of the thin elastic fibers in the alveolar wall were slightly sinuous and ended with rounded tips. Type-II pneumocytes had proliferated and were distributed uniformly over the alveolar surface. Smooth muscle actin filaments were detected only around the alveolar orifice. These findings show that in UIP destruction of the elastic fiber framework of the alveoli may lead to irreversible focal alveolar collapse after damage to the alveolar epithelial cells, and proliferation of type-II pneumocytes may be involved with this elastolysis.  相似文献   
96.
The CX3C chemokine fractalkine (CX3CL1) exists as both a membrane-bound form promoting firm cell-cell adhesion and a soluble form chemoattracting leukocytes expressing its receptor CX3CR1. When adenoviral vector expressing mouse fractalkine (AdFKN) was transduced to the tumor cells, fractalkine was expressed as both membrane-bound form on the tumor cells and soluble form in the supernatant in vitro. Intratumoral injection of AdFKN (1 x 10(9)PFU/tumor) into C26 and B16F10 tumors resulted in marked reduction of tumor growth compared to control (C26: 86.5%, p<0.001; B16F10: 85.5%, p<0.001). Histological examination of tumor tissues revealed abundant infiltration of NK cells, dendritic cells, and CD8(+) T lymphocytes 3 and/or 6 days after treatment with AdFKN. Splenocytes from mice treated by AdFKN developed tumor-specific cytotoxic T cells, and thereby protected from rechallenging with parental tumor cells. Antitumor effects by AdFKN were completely abrogated in both NK cell-depleted mice and CD8(-/-) mice, and partially blocked in CD4(-/-) mice. These data indicated that fractalkine mediates antitumor effects by both NK cell-dependent and T cell-dependent mechanisms. This study suggests that fractalkine can be a suitable candidate for immunogene therapy of cancer because fractalkine induces both innate and adaptive immunity.  相似文献   
97.
Bacteria produce many types of hemolysin that induce diarrhea by mechanisms that are not completely understood. Aeromonas sobria hemolysin (ASH) is a major virulence factor produced by A. sobria, a human pathogen that causes diarrhea. Since epithelial cells in the intestine are the primary targets of hemolysin, we investigated the effects of ASH on ion transport in human colonic epithelial (Caco-2) cells. ASH increased short-circuit currents (Isc) in a dose-dependent manner, and it also activated a 125I efflux from Caco-2 cells. ASH-induced Isc increases and 125I efflux activations were both suppressed by low Ca2+ levels in the extracellular solution or by pretreatment with the Ca2+ chlelator BAPTA-AM. Intracellular Ca2+ levels were increased by ASH in a biphasic fashion characterized by a rapid sharp increase (peak 1) followed by a sustained low plateau (peak 2). ASH-induced peak 1 was inhibited by pretreatment with pertussis toxin, indicating that Ca2+ was mobilized from intracellular stores, and peak 2 was induced by an influx of extracellular Ca2+. Peak 2 but not peak 1 was related to Cl- secretion. These results indicate that ASH activates Ca2+-dependent Cl- secretion.  相似文献   
98.
Myotonic dystrophy type 1 (DM1) is a debilitating multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant splicing of several genes has been reported to contribute to some symptoms of DM1, but the cause of muscle weakness in DM1 and elevated Ca2+ concentrations in cultured DM muscle cells is unknown. Here, we investigated the alternative splicing of mRNAs of two major proteins of the sarcoplasmic reticulum, the ryanodine receptor 1 (RyR1) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) 1 or 2. The fetal variants, ASI(-) of RyR1 which lacks residue 3481-3485, and SERCA1b which differs at the C-terminal were significantly increased in skeletal muscles from DM1 patients and the transgenic mouse model of DM1 (HSA(LR)). In addition, a novel variant of SERCA2 was significantly decreased in DM1 patients. The total amount of mRNA for RyR1, SERCA1 and SERCA2 in DM1 and the expression levels of their proteins in HSA(LR) mice were not significantly different. However, heterologous expression of ASI(-) in cultured cells showed decreased affinity for [3H]ryanodine but similar Ca2+ dependency, and decreased channel activity in single-channel recording when compared with wild-type (WT) RyR1. In support of this, RyR1-knockout myotubes expressing ASI(-) exhibited a decreased incidence of Ca2+ oscillations during caffeine exposure compared with that observed for myotubes expressing WT-RyR1. We suggest that aberrant splicing of RyR1 and SERCA1 mRNAs might contribute to impaired Ca2+ homeostasis in DM1 muscle.  相似文献   
99.
100.
Novel segmented multiblock copolymers ( 7 ) were synthesized by linking poly(ethylene oxide) (PEO) blocks with poly(β-benzyl L -aspartate)(PBLA) blocks via urethane and urea bonds, which were formed by the reaction of 4,4′-methylenediphenyl isocyanate ( 5 ) with the terminal hydroxyl groups of α-hydro-ω-hydroxypoly(oxyethylene) ( 4 ) and the terminal amino groups of poly(β-benzyl L -aspartate)-block-iminohexamethyleneimino-block-poly(β-benzyl L -aspartate) ( 3 ) [prepared from 1,6-hexanediamine ( 1 ) and β-benzyl L -aspartate N-carboxy anhydride ( 2 )], respectively. Membranes with various water contents were obtained from these copolymers by changing the lengths of the PEO and PBLA segments. The study of the permeation of 1-phenyl-1,2-ethanediol, vitamin B12 and myoglobin through the membranes showed a high dependency of the permeability on the molecular weight of the solutes.  相似文献   
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