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81.
目的研究胰腺炎相关蛋白Ⅰ(pancreatitis assoc iated prote inⅠ,PAPⅠ)在急性胰腺炎(acute pancreatitis,AP)动物模型胰腺组织中的表达特点及意义。方法大鼠轻型胰腺炎(m ild acute pancreatitis,MAP)和重型胰腺炎(severe acute pancreatitis,SAP)模型由逆行胰胆管注射1.5%及3.0%牛磺胆酸钠制备。采用反转录聚合酶链反应(RT-PCR)法检测胰腺组织PAPⅠmRNA的表达,同时检测胰腺组织病理改变、湿/干质量比率、腹水量以评价炎症程度。结果PAPⅠmRNA在正常对照组无表达,AP造模后6 h即明显升高,24 h达高峰,48 h迅速下降。SAP组PAPⅠmRNA表达水平在6、24、48、72 h各时间点均显著高于MAP组(P<0.05)。同时PAPⅠmRNA表达与胰腺组织病理、胰腺组织湿/干质量比率和腹水量相关。结论PAPⅠmRNA的表达变化与AP时胰腺组织损伤程度相关。  相似文献   
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BACKGROUND/PURPOSE: This study was designed to investigate the effects of 6 months of nocturnal nasal positive pressure ventilation (NNPPV) on respiratory muscle function and exercise capacity in patients with chronic respiratory failure. METHODS: A prospective, randomized, controlled design was used. Twenty-nine patients with chronic respiratory failure were enrolled and allocated to either the NNPPV (n = 14) or control group (n = 15). Patients in the NNPPV group received bi-level positive pressure ventilation via nasal mask for 6 consecutive months. Arterial blood gas, respiratory muscle assessment and 6-minute walk test (6MWT) were performed before and after the 6-month NNPPV intervention. Respiratory muscle function was assessed using the variables of maximal inspiratory pressure (Pimax), maximal expiratory pressure (Pemax), and maximum voluntary ventilation (MVV). RESULTS: Subjects in the NNPPV group showed a significant improvement in blood gas exchange and increased 6-minute walk distance (6MWD) compared to baseline and the control group. The 6MWD was significantly increased from 257.1 +/- 114.1 to 345.2 +/- 109.9 m (34.3%) in the NNPPV group. NNPPV also significantly improved MVV and Pimax relative to baseline. MVV was significantly increased from 19.2 +/- 6.5 to 22.3 +/- 7.1 L/min (16.1%) in the NNPPV group (p < 0.05). Furthermore, there was a significant correlation between the magnitude of MVV improvement and 6MWD change. CONCLUSION: The 6-month NNPPV treatment significantly decreased the partial pressure of carbon dioxide and improved daytime respiratory muscle function, thus contributing to exercise-capacity increase in patients with chronic respiratory failure.  相似文献   
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85.
Introduction of macromolecules into synaptosomes using electroporation   总被引:1,自引:0,他引:1  
Synaptic terminals are sites of high metabolic activity and thus are particularly vulnerable to oxidative stress. Oxidative damage to proteins can be toxic to neurons and may cause irreversible cell damage and neurodegeneration. A neuroprotective mechanism used by cells to combat oxidative damage is to selectively degrade damaged proteins. Therefore, it is of interest to study the mechanism of degradation of oxidatively damaged proteins in synaptosomes. One way of oxidizing synaptosomal proteins in vitro is by incubating intact synaptosomes in the presence of an oxidizing agent. A problem with this approach is that it may also cause oxidative damage to the machinery required to recognize and degrade oxidized proteins. We have, therefore, introduced a fluorescent macromolecule into synaptosomes to assess the feasibility of using this technique to study how oxidized proteins are degraded and removed from synaptic terminals. Synaptosomes were subjected to electroporation in the presence of FITC labelled-dextran with an average molecular weight of 70000 (FD-70) and non-specific binding was determined by running parallel experiments in lysed synaptosomes. Following extensive washing, synaptosomes were assayed for the presence of intra-synaptosomal FD-70 by measuring fluorescence in a microplate fluorescence reader. Significant differences in fluorescence were found between intact and lysed synaptosomes with maximal uptake at 100 V/ 1500 microF (approx. 36 pmol/mg protein). To determine if membrane transport was compromised by electroporation, uptake of 3H-arginine was compared in control and electroporated synaptosomes. While untreated electroporated synaptosomes showed a loss of 22% in the ability to transport arginine, preincubation in the presence of 1 mM ATP resulted in a complete restoration of arginine transport. These results show that electroporation is a potentially useful technique for introducing a specific oxidized protein, into synaptic terminals so its metabolic fate can be examined.  相似文献   
86.
BACKGROUND: Insomnia causes severe distress in patients with breast cancer who receive chemotherapy. Few studies have focused on using objective methods to assess sleep. This study explored the quality of sleep and related factors in patients with breast cancer during chemotherapy. METHODS: The participants were 16 women with stage I or II breast cancer receiving their third cycle of chemotherapy with cyclophosphamide, epirubicin and fluorouracil, or cyclophosphamide, methotrexate and fluorouracil. The effects of chemotherapy on sleep were assessed on the 8th and 9th days of the third cycle, i.e. the active phase in terms of side effects, and the last 2 days before the start of the fourth cycle for comparison. Instruments used to assess sleep quality and related factors included actigraphy, the Hospital Anxiety and Depression Scale (HADS), the Symptom Distress Scale (SDS), the Fatigue Visual Analogue Scale (FVAS), the Epworth Sleepiness Scale (ESS), and sleep logs. RESULTS: During the active phase, patients showed an anxiety tendency with an average HADS score of 7.8 +/- 3.8. The average FVAS score was 4 +/- 2, indicative of mild fatigue, and SDS score (1.8 +/- 0.3) also indicated mild symptom distress. The number of awakenings each night was 2.2 +/- 1.6 by sleep logs, and the total time spent awake during these episodes was 47.8 +/- 26.1 minutes by Actiwatch. Sleep efficiency measured by Actiwatch in the active phase was 82.1 +/- 9.4% below the normal limit. Daytime sleepiness assessed by ESS showed mild sleepiness (6.0 +/- 3.5) in the active phase. CONCLUSION: The study showed poor sleep quality and daytime sleepiness in patients with breast cancer during the active phase of chemotherapy. Chemotherapy may bring symptom distress to patients and adversely influence sleep quality.  相似文献   
87.
Treatment of cerebral malaria with intravenous quinine is frequently associated with life-threatening cardiotoxicity. We report a case of imported cerebral malaria successfully treated with artesunate-mefloquine combination therapy. The 27-year-old woman presented with fever, sudden onset of binocular blindness and altered consciousness 10 days after a short stay in Indonesia. Hyperparasitemia with Plasmodium falciparum and P. vivax in more than 5% of red blood cells was demonstrated on peripheral blood smear. She was admitted to the intensive care unit due to shock, jaundice and acute renal failure. Because of a shortage of intravenous quinine, intravenous artesunate was given as an alternative. Her condition stabilized on the 3rd day of therapy, with resolution of fever and disappearance of parasitemia. Consolidation therapy with oral mefloquine and primaquine was then given to prevent recrudescence and relapse. The only adverse event associated with artesunate was transient reticulocytopenia, which resolved after discontinuation of therapy. Her vision completely recovered, along with renal and liver function.  相似文献   
88.
BACKGROUND: Quality of life (QOL) is now considered to be an important part of the assessment of dialysis patients. The aim of this study was to develop and assess the reliability, validity and sensitivity of the dialysis module of the World Health Organization Quality of Life - Brief (WHOQOL-BREF) Taiwan version [WHOQOL-BREF(TW)] in patients undergoing regular hemodialysis (HD). METHODS: QOL survey was administered to 283 regular HD patients in metropolitan Taipei. The instruments used included: (1) the proposed module - composed of the core part, the WHOQOL-BREF(TW), and the six specific items; (2) the symptom/problem (S/P) scale - composed of 12 items specific for dialysis patients; (3) the utility measure, which was performed with standard gamble (SG) methods; and (4) the rating scale (RS). RESULTS: Based on the six criteria of validity, reliability and variance of the items, four HD-specific items were selected. Reliability study showed that Cronbach's alphas, composite reliability, and test-retest reliability (intraclass correlation at an average retest interval of 4-8 weeks) of the four domains of physical, psychological, social relationship and environment, ranged from 0.74-0.82, 0.79-0.84 and 0.61-0.79, respectively. Validity study showed that all the correlations between an item and its corresponding domain were highly significant (r>0.4, p<0.01) and larger than the correlations between the item and other domains. SG and psychometric measures showed relatively low correlations (0.12-0.26). The module showed the same construct as the WHOQOL-BREF(TW) under confirmatory factor analysis, whereas the exploratory factor analysis showed mild variation. Convergent and discriminant validity were good. Global QOL, physical, psychological and environment domains had some sensitivity to differentiate the severity of the condition of patients receiving HD. Clinical validity was demonstrated in global QOL, physical and psychological domains to have significant correlations with S/P scores. CONCLUSION: Besides broader coverage than the core WHOQOL-BREF(TW), the dialysis module of the WHOQOL-BREF(TW) is a valid, reliable and sensitive QOL instrument for the assessment of HD patients in Taiwan.  相似文献   
89.
Prodelphinidin B-2 3'-O-gallate, a proanthocyanidin gallate isolated from green tea leaf, was investigated for its anti-proliferative activity in human non-small cell lung cancer A549 cells. The results showed that prodelphinidin B-2 3'-O-gallate inhibited the proliferation of A549 cells with no detectable toxic effects on normal WI-38 cells as measured by the XTT assay. Flow cytometric analysis showed that prodelphinidin B-2 3'-O-gallate blocked cell cycle progression in the G0/G1 phase. In addition, prodelphinidin B-2 3'-O-gallate effectively induced A549 cell apoptosis as determined by assessing the nucleosome level in cytoplasm. Enzyme-linked immunosorbent assay showed that the G0/G1 phase arrest is due to p53-independent induction of p21/WAF1. An enhancement in Fas/APO-1 and its two form ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by prodelphinidin B-2 3'-O-gallate. We suggested that prodelphinidin B-2 3'-O-gallate's activities might be potentially contribute to its overall chemopreventive effects against lung cancer, and can possibly be considered for future therapeutic application.  相似文献   
90.
PURPOSE: Our goal was to determine whether dynamic MR subtraction images could be used to detect and stage gastric tumors. METHOD: Dynamic MR subtraction images were prospectively performed in 20 patients without gastric lesions and in 39 patients with gastric tumors. The flat- or depressed-type early gastric cancers were excluded. The MR findings were assessed for layered pattern of the normal gastric wall, detectability of tumors, enhanced pattern of tumor, and depth of the tumor invasion. Surgical specimens were obtained from 30 of the patients with tumors, and histopathologic sections were made in the dynamic MR scanning direction. RESULTS: The three-layered structure of the normal gastric wall was apparent in more of the dynamic MR subtraction images (60%) than of the nonsubtraction images (30%) in the control group. All 39 gastric tumors were detected by MRI. The intact inner layers overlying stromal tumors and outer layers interrupted by advanced gastric cancers were clear on the subtracted images. MRI accurately T-staged 88% of the gastric cancers. CONCLUSION: Dynamic MR subtraction images can be used to identify gastric tumors and to stage gastric cancers.  相似文献   
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