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91.
AIM: Taraxacum officinale (TO) has been frequently used as a remedy for inflammatory diseases. The aim of this study was to investigate the effect of TO on cholecystokinin (CCK)-octapeptide-induced acute pancreatitis in rats.METHODS: TO at 10 mg/kg was orally administered, followed by 75 μg/kg CCK octapeptide injected subcutaneously three times after 1, 3 and 5 h. This whole procedure was repeated for 5 d. We determined the pancreatic weight/body weight ratio, the levels of pancreatic HSP60 and HSP72, and the secretion of pro-inflammatory cytokines. Repeated CCK octapeptide treatment resulted in typical laboratory and morphological changes of experimentally-induced pancreatitis.RESULTS: TO significantly decreased the pancreatic weight/body weight ratio in CCK octapeptide-induced acute pancreatitis. TO also increased the pancreatic levels of HSP60 and HSP72. Additionally, the secretion of IL-6 and TNF-α decreased in the animals treated with TO.CONCLUSION: TO may have a protective effect against CCK octapeptide-induced acute pancreatitis.  相似文献   
92.
93.
Summary: Polymer blend nanocomposites containing linear low density polyethylene (LLDPE), nylon 6 and organoclays were prepared by melt mixing, and their morphologies and structures were examined with a field emission scanning electron microscope (FE‐SEM) and an X‐ray diffractometer (XRD). The size of phase‐separated domains decreased considerably with increasing content of organoclay. The d‐spacing of organoclay in the nanocomposites was increased from about 18.6 to over 28 Å. This effect was highly dependent on nylon 6 contents because nylon 6 is more polar and shows higher affinity to the organoclays compared to LLDPE.

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94.
BACKGROUND: Serratia marcescens is an aerobic gram-negative bacillus belonging to the family Enterobacteriacea. Infections caused by S marcescens may be difficult to treat because of their resistance to a variety of antibiotics, including beta-lactams and aminoglycosides. METHODS: This study aimed to (1) identify the risk factors associated with the development of Serratia marcescens bacteriuria in neurosurgical intensive care units (NSICU); (2) genotype the pathogens to determine the source of infection; (3) compare these results with antibiograms; and (4) determine and implement appropriate control measures. A retrospective case-control study of the epidemiologic data, the surveillance of environmental cultures, and the genotyping of strains using arbitrarily primed polymerase chain reaction (AP-PCR) were performed at a 750-bed, tertiary care teaching hospital. Seventy-four bacteriuria patients were compared with 74 age/sex-matched control patients in the NSICU between March 2002 and March 2004. The factors assessed were patient demographics; duration of hospital stay; duration of indwelling catheter use before and during stay in the NSICU; chronic underlying illnesses (diabetes mellitus, cardiovascular disease, malignancy); other sites of infection; history of trauma; exposure to a nasogastric tube; mechanical ventilation; urinary catheterization; central venous catheterization; surgical drainage; tracheostomy; brain or spine surgery; and receipt of total parenteral nutrition (TPN), antimicrobials (beta-lactams, aminoglycosides, quinolones, carbapenems, vancomycins), or steroids. RESULTS: Patients with S marcescens bacteriuria were more likely to have a longer NSICU stay and other sites of infection. Environmental surveillance showed the handling of urine jugs to be the point source of contamination. Genotyping and antibiograms of 14 patients were the same except for those of 2 patients. CONCLUSION: The patient-related risk factors were identified, and a rapid identification of the organism was made. Heightened surveillance, infection control measures, and empiric therapy led to improved methods for handling urine jugs, which terminated the outbreak.  相似文献   
95.
BACKGROUND: LNCaP and its derivative cell lines, which include C4-2 (and the related C4-2B) and CL1, are used as models of prostate cancer. Unlike LNCaP, the other cell lines show features of progressed disease such as metastatic capability and hormone independence. Analyses were done to determine if C4-2 or CL1 cells were selected from pre-existent subpopulations in LNCaP. METHODS: Prostate cancer cells were characterized by cluster designation (CD) phenotyping. Specific cell populations were sorted by flow cytometry. DNA array analysis was used to probe differential gene expression. RESULTS: CD phenotyping showed that CL1 and C4-2 (and C4-2B) were very dissimilar, and C4-2 was more similar to LNCaP. One common difference between LNCaP and its derivatives was CD26, in which virtually all C4-2 or CL1 cells were CD26(+) but only approximately 10% of LNCaP cells were CD26(+). The CD26(+) subpopulation of LNCaP was isolated and cultured in vitro. After culture, a high percentage of the cells (descended from the sorted cells) were CD26(+), in contrast to those sorted by CD13 or CD44. The cultured CD13 and CD44 populations did not show a high percentage of CD13(+) and CD44(+) cells, respectively. CD13 and CD44 are markers, in addition to CD26, for CL1 but not for C4-2. CONCLUSIONS: C4-2 arose probably from CD26(+) LNCaP cells, while CL1 arose de novo.  相似文献   
96.
Pulmonary tuberculosis in patients with idiopathic pulmonary fibrosis   总被引:2,自引:0,他引:2  
OBJECTIVES: Patients with idiopathic pulmonary fibrosis (IPF) have an increased risk of pulmonary tuberculosis. However, detecting pulmonary tuberculosis may be difficult due to the underlying fibrosis. The aim of this report is to describe the radiological and clinical findings of pulmonary tuberculosis in patients with idiopathic pulmonary fibrosis. MATERIALS AND METHODS: We reviewed 143 consecutive patients in whom IPF was diagnosed by either the histological or radio-clinical criteria. Among them, nine patients were histologically (n=2) or bacteriologically (n=7) confirmed to have active pulmonary tuberculosis. The location and patterns of pulmonary tuberculosis were examined on a thin section CT scan. RESULTS: The most common thin section CT findings were subpleural nodules (n=6; mean diameter, 3.2 cm) and a lobar or segmental consolidation (n=3). The lesions were located most commonly in the right lower lobe (n=4). The incidence of tuberculosis in patients with idiopathic pulmonary fibrosis was more than five times higher than that of the general population. CONCLUSION: The atypical manifestation of pulmonary tuberculosis is common in patients with idiopathic pulmonary fibrosis, which may mimic lung cancer or bacterial pneumonia.  相似文献   
97.
Since the diagnosis of extrapulmonary tuberculosis (EPT) is largely depended on the physician's suspicion in respect of the disease, we believed that it would be worthwhile to scrutinize the clinical characteristics of EPT. Thus, here we present retrospectively evaluated clinical manifestations of patients who were diagnosed as EPT cases in a tertiary referral care hospital. Medical records of 312 patients, diagnosed as having EPT at Yongdong Severance hospital from January 1997 to December 1999, were reviewed retrospectively. In total 312 patients, 149 (47.8%) males and 163 (52.2%) females aged from 13 years to 87 years, were included into this study. The most common site of the involvement was pleura (35.6%). The patients complained of localized symptoms (72.4%) more frequently than systemic symptoms (52.2%). The most common symptom was pain at the infected site (48.1%). Leukocytosis, anemia, and elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were found in 12.8%, 50.3%, 79.3% and 63.1% of the patients, respectively. Twenty-four percent of the patients had underlying medical illnesses such as, diabetes mellitus or liver cirrhosis, or were over 60 years old. In 67.3% of patients, tuberculosis was suspected at the initial visit. However, tuberculosis was microbiologically proven in only 23.7% of the patients. The time interval from the symptom onset to the diagnosis varied, with the mean duration of the period 96 days. Pulmonary parenchymal abnormal lesions were found in 133 patients (42.6%) on chest radiographs. EPT has a wide spectrum of clinical manifestations, so it is difficult to diagnose it. Based on our studies, only 11.2% of the patients were confirmed as EPT. So it is important that the physician who first examines the patient should have a high degree of suspicion based on the chest radiography, localized or systemic symptoms and several laboratory parameters reviewed in this study.  相似文献   
98.
RATIONALE AND OBJECTIVES: We assess the value of computed tomography perfusion image (CTPI) obtained by postprocessing the CT data in the diagnosis of pulmonary embolism. METHODS: An experimental pulmonary embolism model was made in 6 pigs by injecting 2 types of emboli into the pulmonary arteries. For each pig, 5 type-A (diameter 3.5 x 8 mm) and 5 type-B (diameter 2.5 x 6 mm) emboli were injected through a catheter with the distal tip located in the inflow tract of the right atrium. After obtaining precontrast and postcontrast CT data during a single breath-hold using a 4-slice multidetector CT, perfusion images were generated by data subtraction. Approximately 150 to 180 mL of contrast material was injected at an injection rate of 6 mL/s to obtain postcontrast CT. Three independent observers twice analyzed CT images for the presence of emboli: once with postcontrast CT scans (CT angiography: CTA) alone and again with both CTA and CTPI. The locations of the emboli in the pulmonary arteries were confirmed by examining the killed porcine lungs. RESULTS: The sensitivity and positive predictive value in the detection of pulmonary emboli with CTA alone were 59% (106/180) and 87% (106/122), respectively. The sensitivity and positive predictive value with both CTA and CTPI were 87% (156/180) and 85% (156/184), respectively. For type-A emboli, the sensitivity with both CTA and CTPI (76/90, 85%) was better than that with CTA alone (63/90, 70%) (P < 0.001). For type-B emboli, the sensitivity with both CTA and CTPI (80/90, 89%) was also better than that of CTA alone (43/90, 48%) (P < 0.001). CONCLUSIONS: CTPI could be obtained using digital subtraction of the CT data. It appeared to be an adjunct in enhancing the diagnostic accuracy of pulmonary embolism, particularly when detecting small pulmonary emboli.  相似文献   
99.
Kim YM  Lee JY  Choi SH  Kim DG  Jahng JW 《Brain research》2004,1018(2):221-226
It has been reported that food deprivation decreases expression of neuronal nitric oxide synthase (nNOS) in the hypothalamic paraventricular nucleus (PVN). Food deprivation produces autonomic changes and the PVN nitric oxide has been suggested to be involved in regulation of autonomic functions. In order to understand the molecular mechanism by which food deprivation decreases nNOS expression in the PVN, we examined if plasma glucocorticoids, which reported to be elevated during food deprivation, mediates the fasting-induced down-regulation of the PVN-nNOS. Male Sprague-Dawley rats underwent 48 h of food deprivation, but not water deprivation, with/without subcutaneous RU486, glucocorticoid receptor antagonist, and the brain tissues were processed for immunohistochemistry with specific antibodies against nNOS. Immunoreactivity of phosphorylated cAMP response element-binding protein (pCREB) was also examined in the PVN sections, because nNOS promoter carries cAMP response element (CRE). Food deprivation significantly decreased both nNOS and pCREB immunoreactivity (-ir) in the medial parvocellular PVN, and RU486 blocked this reduction. In the posterior magnocellular PVN, nNOS-ir, but not pCREB-ir, was decreased by food deprivation, and RU486 exerted no effect. These results suggest that glucocorticoid receptor may mediate the fasting-induced down-regulation of nNOS in the parvocellular PVN, but not in the magnocellular PVN.  相似文献   
100.
Kang HG  Jeong SH  Cho JH  Kim DG  Park JM  Cho MH 《Toxicology》2004,199(2-3):219-230
Chlorpyrifos-methyl (CPM), an organophosphate insecticide, widely used for grain storage and agriculture, has been suspected as endocrine disrupter by a few in vitro studies. This study was performed to investigate the (anti-) estrogenicity and (anti-) androgenicity of CPM in vivo using immature rat uterotrophic assay and rat Hershberger assay. CPM with or without 17beta-estradiol were administered to 20 days old female rats to investigate its (anti-) estrogenic activity. Uterine and vaginal weight, uterine epithelial cell height were not affected by the treatment of CPM (2, 10, 50, 250 mg/kg). CPM 250 mg/kg potentiated relative vagina weight in 17beta-estradiol treated immature female rats without any changing of uterine weight. Relative liver weight was increased with decrease of body weight by CPM 250 mg/kg treatment. Uterine cell proliferation tested with bromodeoxyuridine labeling index was not observed in CPM treated rats. CPM with or without testosterone propionate were administered to castrated rat of 51 days old for 10 days to investigate the (anti-)androgenic activity,. The weight of relative and absolute androgen-dependent accessory sex organs; seminal vesicle with coagulating glands (SV/CG), ventral prostate gland (VP), glans penis (GP), levator ani plus bulbocarvernosus muscle (LABC) and Cowper's gland (CG,) were unchanged by the treatment of CPM alone. While CPM induced the increase of relative adrenal gland weight, CPM 50mg/kg decreased the weights of CV/CG, VP, CG and LABC without change of GP without changing of GP when it was treated with TP. In conclusion, CPM dose not show estrogenic and anti-estrogenic activity in immature female rats, but it represents anti-androgenic activity by inhibition of the TP-stimulated increase of the weight of accessory sex organs.  相似文献   
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