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Photocarcinogenesis and inhibition of intercellular adhesion molecule 1 expression in cells of DNA-repair-defective individuals 下载免费PDF全文
3.
G Kretschmer E Rossmann E Gruber T Pratschner M Schemper F Piza F Zekert P Polterauer 《Helvetica chirurgica acta》1991,57(4):649-653
To determine whether acetyl salicylic acid (ASA) in a daily dose of 1500 mg versus untreated controls is effective in patients with peripheral arterial disease a prospective randomized but not placebo-controlled one single centre trial was undertaken. Patients were assigned to one of two groups by means of multi-dimensional contingency tables whereas the risk factors age, sex, height, body weight, diabetic metabolic state, hypertension, history of myocardial infarction, smoking habits and preoperative clinical status according to the Fontaine classification where found in the state of balance. 298 patients with arterial occlusions in the iliaco-femoro-popliteal level were recruited during 1971-1974, the primary end points were probability of patency and probability of survival. In regard as well as to the probability of patency (p less than 0.56 Breslow, p less than 0.66 Mantel) as to the probability of survival (p less than 0.10 Breslow, p less than 0.70 Mantel) no statistical significant difference was detected. In conclusion ASA, in the doses administered here, was unable to improve patency or prolong patient survival, an outcome, which is at variance with results obtained by others. 相似文献
4.
Michael Burwinkel Constanze Riemer Anja Schwarz Julia Schultz Sabine Neidhold Theresa Bamme Michael Baier 《International journal of developmental neuroscience》2004,22(7):497-505
Prion infections of the central nervous system (CNS) are characterised by a reactive gliosis and the subsequent degeneration of neuronal tissue. The activation of glial cells, which precedes neuronal death, is likely to be initially caused by the deposition of misfolded, proteinase K-resistant, isoforms (termed PrP(res)) of the prion protein (PrP) in the brain. Cytokines and chemokines released by PrP(res)-activated glia cells may contribute directly or indirectly to the disease development by enhancement and generalisation of the gliosis and via cytotoxicity for neurons. However, the actual role of prion-induced glia activation and subsequent cytokine/chemokine secretion in disease development is still far from clear. In the present work, we review our present knowledge concerning the functional biology of cytokines and chemokines in prion infections of the CNS. 相似文献
5.
We proposed that double exposure to stressors at work and from family are associated with increased coronary risk in women and that the same exposures are accompanied by depressive feelings. The study group comprised 292 women coronary patients (30-65 years) and 292 age-matched healthy controls. Work-stress, marital-stress, and depressive symptoms were assessed by standardized questionnaires and evaluated in both case-control and 5-year follow-up analyses. We found that double exposure to stress from work and family was accompanied by the highest risk and the worst prognosis in women's coronary disease. In women patients depressive feelings were frequent, and they were more closely related to family than to work stress. In healthy women, both stressors, but in particular their combination, lead to depressive symptoms. 相似文献
6.
Prognostic value of MMP-2, -9 and TIMP-1,-2 immunoreactive protein at the invasive front in advanced head and neck squamous cell carcinomas 总被引:10,自引:0,他引:10
Ondruschka C Buhtz P Motsch C Freigang B Schneider-Stock R Roessner A Boltze C 《Pathology, research and practice》2002,198(8):509-515
In head and neck cancer as well as in other carcinomas, tumor expansion and spread to distant sites require the secretion of destructive enzymes that degrade the extracellular matrix. A variety of proteases contribute to matrix destruction. Characteristics of the invasive tumor front may reflect tumor prognosis better than do other parts of the tumor. Therefore, it was the aim of the present study to (i) compare central and peripheral tumor zones for differences in the expression of matrix-metalloproteinases (MMP) -2 and -9 and their naturally occurring inhibitors (tissue inhibitor of matrix-metalloproteinases (TIMP) -1 and -2), (ii) examine the morphological potential of malignancy, and (iii) correlate these findings with clinicopathological parameters. The study population consisted of 106 surgical specimens of advanced head and neck squamous cell carcinomas. The invasive front was graded for malignancy, and immunohistochemical staining with MMP-2, MMP-9, TIMP-1 and TIMP-2 antibodies was performed. Both MMP-2 and MMP-9 were found to be significantly overexpressed at the tumor front. The MMP-2-positive invasive front exhibited diminished overall survival times. In multivariate analysis, MMP-2 expression retained its correlation with overall survival in addition to nodal status and total malignancy score. Expression of TIMP-2 correlated with local tumor invasion. We conclude that the expression of MMP-2 at the invasive front is a marker of poor survival and appears to be associated with early recurrence in initially lymph node-negative patients. 相似文献
7.
Michelle Bonnett Tracie Wallis Michelle Rossmann Nat L Pernick David Bouwman Kathryn A Carolin Daniel Visscher 《Modern pathology》2003,16(2):154-160
Appropriate follow-up of patients with needle core breast biopsies (NCBB) showing atypical hyperplasia remains unclear because previous studies show that subsequent open biopsies in variable proportions of these patients reveal ductal carcinoma in situ (DCIS) or even invasive carcinoma, indicating significant sampling artifact. NCBB with diagnoses of atypia were morphologically classified into groups as follows: I, ALH (n = 24); II, ADH with minimal cytologic atypism (n = 90); III, atypia, other (9 columnar, 2 apocrine, 11 atypical papillary); IV, severe ADH/borderline DCIS (n = 31). Mammographic and histologic features, including the number of foci of atypia in the NCBB and the calcification span, were then correlated with presence of DCIS or invasive tumor in subsequent open excisions. Open excisional biopsies showed more severe lesions in 12% of Group I-III cases (8% in Group I, 9% in Group II, and 27% in Group III), of which 15 were DCIS and one was an invasive tubular carcinoma (0.3 cm). Of the DCIS, 60% (n = 9) were < or =5 mm, and 13 of 15 (87%) were low grade. The NCBB cavity was immediately adjacent to the more severe lesions in 88% (n = 14) of cases, in keeping with sampling error. The subset showing severe ADH with borderline nuclear features in contrast was associated with a high likelihood (63%) of DCIS in follow-up excisions. NCBB with atypical papillary features also showed a high frequency of DCIS (4/11, 36%) in subsequent open excisions. Other factors associated with more severe lesions on open biopsy included the number of atypical foci in the NCBB (>4, P <.05) and the mammographic calcification span (>2.0 cm, P <.0001). Atypical lesions diagnosed in NCBB samples are radiographically and morphologically heterogeneous, accounting for the variable frequency of DCIS or invasive neoplasm identified in subsequent open excisions, which are usually focal, low grade, and a consequence of sampling artifact (i.e., adjacent to the NCBB cavity). DCIS is more likely if microcalcifications are mammographically extensive or if atypia is multifocal or is associated with borderline cytologic features. 相似文献
8.
S Kim U Boege S Krishnaswamy I Minor T J Smith M Luo D G Scraba M G Rossmann 《Virology》1990,175(1):176-190
The structure of Mengo virus had been determined from crystals grown in the presence of 100 mM phosphate buffer at pH 7.4. It is shown that Mengo virus is poorly infectious at the phosphate concentration similar to that in which it was crystallized. Maximal infectivity is achieved at 10 mM phosphate or less in physiological saline. The phosphate effect is ameliorated when the pH is lowered to 4.6. Although it has not been possible to study the crystal structure of the virus at low phosphate concentrations, it is shown that increasing the Cl- concentration at pH 6.2 or decreasing the pH to 4.6 causes substantial conformational changes confined to the "pit," a deep surface depression. These structural changes involve a movement of the "FMDV loop" (GH loop) in VP1, an ordering of the "VP3 loop" (GH loop in VP3) between 3176 and 3182, the displacement of a bound phosphate near the "FMDV loop" (GH loop in VP1), and movement of the carboxy terminus of VP2. The changes in conformation are correlated with the dissociation of the virion into pentamers at pH 6.2 and 150 mM Cl-. The localization of the conformational changes and the correlated role of the phosphate in controlling infectivity support the hypothesis that the "pit" is the receptor attachment site. 相似文献
9.