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81.
The presence of serum markers of hepatitis B virus (HBV) infection in different stage of illness has a specific pathogenic and diagnostic significance. Based on the frequency of the appearance of HBV markers in patients' sera at different stages of the illness, we attempted a grouping possibly helpful for differentiation, epidemiologic and prognostic evaluation of hepatitis. The significance for chronic disease development of the dynamics of HBV marker levels in the serum is discussed.  相似文献   
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83.
PURPOSE: The authors wanted to identify those patients assessed by exercise SPECT in whom the quantification of lung Tl-201 uptake helps to evaluate disease prognosis. METHODS: One hundred forty-nine patients (114 men, 35 women; 74 after myocardial infarction [MI]; mean age, 54 +/- 9 years) underwent exercise Tl-201 SPECT. The SPECT patterns were divided into normal (n = 45), fixed defects (n = 29), and inducible ischemia (n = 75). Anterior planar imaging was performed before SPECT acquisition to calculate the lung-to-heart ratio (L:H). RESULTS: During an average follow-up of 20 +/- 9 months, eight patients had died of cardiac causes and 13 patients experienced nonfatal MIs. Among the 45 patients with normal perfusion, no cardiac event was observed and the L:H ratio was not helpful for risk stratification. In 29 patients with fixed defects, four cardiac deaths occurred (all in patients with L:H ratios >0.5; annual event rate, 21.1% for L:H ratios >0.5 compared with 0% for L:H ratios <0.5; chi-square = 4.07, P < 0.05). Among the 75 patients with ischemia, 4 died and 13 had nonfatal MIs (annual event rate, 15.4% for L:H ratios >0.5 compared with 13% for L:H ratios <0.5; P = NS). CONCLUSIONS: These findings suggest a benign prognosis in patients with normal SPECT (regardless of the L:H ratio). Conversely, all patients with ischemia are at high risk for future cardiac events. Quantification of the Tl-201 lung uptake seems to be valuable in evaluations of disease prognosis, especially in patients with fixed defects.  相似文献   
84.
In this study we show that benzo[a]pyrene (B[a]P) and the cyclopenta polycyclic aromatic hydrocarbons (CP-PAH) cyclopenta[c,d]pyrene (CPP), benz[j]aceanthrylene (B[j]A) and benz[l]aceanthrylene (B[l]A) induce apoptosis in Hepa1c1c7 cells, as measured by fluorescence microscopy and flow cytometry. The compounds induced formation of the active form of caspase-3, cleavage of its intracellular substrate, poly(ADP-ribose)polymerase (PARP), and DNA fragmentation. B[j]A was found to be the most potent in inducing apoptosis, followed by B[a]P, CPP and B[l]A. All compounds increased expression of CYP1A1 with relative potencies B[j]A > B[a]P > CPP > B[l]A, corresponding well with their relative apoptotic responses. alpha-Naphthoflavone (alphaNF), an inhibitor of CYP1A1, reduced the induced apoptosis. B[a]P and CP-PAH exposure also resulted in an accumulation of the tumour suppressor protein p53. No changes were observed in the protein levels of Bax and Bcl-2, whereas the anti-apoptotic Bcl-xl protein was down-regulated, as judged by western blot analysis. Fluorescence microscopic analysis revealed a translocation of p53 to the nucleus and of Bax to the mitochondria. Furthermore, caspase-8 was activated and Bid cleaved. Interestingly, the levels of anti-apoptotic phospho-Bad (Ser155 and Ser112) had a biphasic increase after B[a]P or CPP treatment. Whereas alphaNF markedly reduced the activation of B[a]P to reactive metabolites, as measured by covalent binding to macromolecules, it did not inhibit the up-regulation of phospho-Bad. Neither of the compounds triggered apoptosis in primary cultures of rat lung cells (Clara cells, type 2 cells and lung alveolar macrophages), possibly due to a lack of CYP1A1 induction. In conclusion, B[a]P and the CP-PAH induced apoptotic as well as anti-apoptotic signals in Hepa1c1c7 cells.  相似文献   
85.
Supernatants from short-term culture of peripheral blood and bone marrow mononuclear cells obtained from 22 multiple myeloma patients were used to measure the concentration of TNF-alpha, HGF, IL-6 and its soluble receptor (sIL-6R), VEGF and bFGF. Cells were cultured with or without thalidomide (THAL). We observed statistically significant decrease in TNF-alpha, HGF, IL-6, sIL-6R in supernatants from THAL cultures compared to cells cultured without THAL. Flow cytometry technique was applied to study the Bcl2 expression on CD 4, CD 8 and CD 138 positive cells. The statistically significant decrease in Bcl2 expression on myeloma cells (CD 138+) was observed both in PB and BM cultures. THAL could inhibit the plasma cell growth both by diminishing proangiogenic cytokines production and enhancing myeloma cell apoptosis.  相似文献   
86.
The effects of 12-O-tetradecanoylphorbol-13-acetate (TPA), 12-deoxyphorbol-13-phenylacetate(DOPP), 12-deoxyphorbol-13-phenylacetate-20-acetate (DOPP A),sapintoxin D (SAP D) and sapintoxin A (SAP A) on the decreasein [125I]epidermal growth factor (EGF) binding (indicating proteinkinase C activation), suppression of gap junctional intercellularcommunication (GJIC) and induction of morphological cell transformation(MCT) in Syrian hamster embryo (SHE) cells were investigated.All five phorbol esters were found to reduce [125I]EGF bindingin early passage SHE cells at comparable concentrations. DOPPA was  相似文献   
87.
Heterozygous mutations in adenomatous polyposis coli (APC) is an early event in inheritable and sporadic colon cancer development. We recently found reduced connexin (Cx43) expression in intestinal cell lines with heterozygous Apc mutation. In this study we investigated Cx expression and the role of one mutated Apc allele in epithelia of multiple intestinal neoplasia (Min) mouse intestines by immunohistochemistry. Cx43 was not expressed in intestinal epithelia of Min and wild-type mice. Cx32 was specifically expressed in enterochromaffin cells in both mice types, and in Paneth cells of wild-type mice. In contrast, Min mice had nearly undetectable level of Cx32 in Paneth cells. Isolated small intestinal crypts from Min mice had markedly increased secretion of both lysozyme and matrilysin compared with wild-type mice. Absence of matrilysin in Min mice reduces adenoma development. Reduced Cx32 and increased matrilysin secretion from Paneth cells could be important to neoplastic development in the intestine.  相似文献   
88.
Hus 《健康大视野》2006,(4):64-65
我是一名护士,我当过最普通的护士、护师,当过最操心的护士长,当过最忙碌的助理员,也曾反串过病人的角色。在20多年的从护生涯中,我对护士职业有过困惑,有过失望,有过欣喜,但更多的是振奋与努力。我热爱这个职业,从多年对护理职业的关注与思索中,我对护理的内涵有些许理解和感悟、热爱护理,理解护理,关注护理,振兴护理是每一名从护人员的责任与义务。下面我将对护理职业的理解及感悟呈献给读者朋友,希望可以抛砖引玉。  相似文献   
89.
90.
Richter transformation (RT) of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) to Hodgkin lymphoma (HL) is a rare and unexpected event in the course of the disease and data on this phenomenon is still limited. To better understand the clinical and histological characteristics and the outcomes of HL variant of RT (HvRS) the Polish Lymphoma Research Group performed a nationwide survey which identified 22 patients with histologically proven HvRS diagnosed between 2002 and 2016. There were 16 (73%) males. The median age at CLL/SLL and HvRS diagnosis was 59 (39‐77) and 64 (40‐77) years, respectively. The median interval between CLL/SLL and HvRS diagnosis was 38 months (range: 0‐187). All patients had an advanced stage HL, and majority, 17 (77%), presented with B symptoms. The predominant subtypes of HL were nodular sclerosis (12; 55%) and mixed cellularity (9; 41%). Eighteen patients received non‐palliative treatment, including 13 who received driamycin, bleomycin, vinblastine, and dacarbazine (ABVD) regimen first line. Objective response was: 50%, with 33% complete remissions (61% and 46% for ABVD, respectively). Median overall survival reached 13.3 months (95% CI, 3.7‐NA). The only adverse prognostic factor for survival was a higher number (≤1 versus ≥2) of prior lines of treatment given for CLL/SLL with HR 3.57 (95% CI, 1.16‐10.92). We conclude, HvRS harbors a poor prognosis, especially in patients heavily pretreated for CLL/SLL. Response to standard first‐line anti‐HL chemotherapy is unsatisfactory, and new agents should be tested to improve the outcome.  相似文献   
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