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81.
David G. Zaridze Andrej Marochko Tamara Basieva Stephen W. Duffy 《International journal of cancer. Journal international du cancer》1993,54(6):889-894
Cancer incidence rates were examined in the native peoples of the far north-east of Siberia for the years 1977–1988. Particularly high rates of cancers of the stomach, lung, oesophagus and cervix were observed. For stomach cancer, the male and female age-standardized (to the world population) rates were 103.9 per 100,000 and 50.0 per 100,000 respectively. The corresponding lung cancer rates were 109.4 and 45.7, and for oesophageal cancer 83.9 and 35.0. The age-standardized cervical cancer rate was 38.5 per 100,000. Rates of these cancers were considerably higher than in native Alaskan peoples, although the latter had higher rates of breast and colorectal cancers. The rates were also much higher than those of the migrant peoples from Russia and elsewhere who have settled in the far north-east over the past 3 centuries, particularly at younger ages. Male rates of stomach and lung cancer were highest in the paleo-Asiatic peoples of the north, whereas male oesophageal rates were highest in the Taiga people. In females, rates of stomach and oesophageal cancers were highest in the paleo-Asiatic peoples, and rates of lung cancer were highest in the Taiga nationalities. Cervical cancer rates were highest in the Amuro-Sakhalin nationalities of the south. Further research is needed at individual levels to explain the very high risks and the differences among the ethnic groups. 相似文献
82.
Incidental prostatic carcinoma (ICP) has good prognosis related to low stage at diagnosis. Few rogressive cases demanding aggressive treatment need early identification. Neoangiogenesis proved its predictive role in prostatic carcinoma after radical prostatectomy. To reveal its value in ICP authors investigated specimens after transurethral resection of prostate (TURP). Retrospective study was performed on 68 ICP diagnosed in years 1985 1989. Microvessels highlighted by factor VIII were counted in a x200 microscope field (0,8012 mm 2 ) in most active areas of neovascularisation. Microvessel count was correlated with tumor differentiation degree, Gleason score, disease stage, and patients survival in at least 9 years after diagnosis. Higher maximal microvessel counts were associated with lower degree of tumor differentiation (p=0,005), Gleason score (p=0,001), and disease stage (0,003). No association with disease progression and patients survival was found. Mean microvessel counts showed less significant values when correlated with tumor differentiation degree (p=0,003) and Gleason score (p=0, 01), and no correlation with other variables. Microvessel density in TURP specimens of ICP retains its prognostic value already demonstrated in carcinoma of peripheral prostatic lobes. Maximal microvessel counts were prognostically more reliable than mean values. 相似文献
83.
Margaret Fedelešová Andrej Džurba Attila Ziegelhöffer 《Biochemical pharmacology》1975,24(20):1847-1850
d,l-aspartic acid as well as its K+ and Mg2+ salts have been found to be inhibitory to Na+ + K+)-ATPase activity of the dog heart microsomal fraction enriched with sarcolemma. According to intensity of the inhibitory effect (noncompetitive) they form the following sequel: mono-K+-aspartate of K+ and Mg2+-aspartate in a molar ratio of 1:1 (K+, Mg2+-ASP). The latter mixture is widely used as an agent in cardiac failure. For (Na+ + K+)-ATPase the salient effects of d,l-aspartic acid and/or its K+ and Mg2+ salts were: (i) decrease in V for ATP as substrate with unchanged Km; (ii) for Na+ as an allosteric modifier of (Na+ + K+)-ATPase activity a decrease in V without any alteration in n as a measure of cooperativity between activating sites; (iii) for K+ a decrease in V and n as well as an increase in K0.5. In the presence of Na+ and ATP the high affinity of the enzyme for K+ became reduced by d,l-aspartic acid, lowering at the same time the K0.5 value.Effects like these have also been described for ouabain. The present data show that K+ and Mg2+ salts of d,l-aspartic acid act at a similar locus as does ouabain. 相似文献
84.
We describe cervids as potential reservoir hosts of Babesia EU1 and B. divergens. Both babesial parasites were found in roe deer. Sequence analysis of 18S rRNA showed 99.7% identity of roe deer Babesia EU1 with the human EU1 strain. B. divergens detected in cervids was 99.6% identical to bovine B. divergens. 相似文献
85.
Henna (Lawsonia inermis) has been used for centuries as a herbal hair and skin dye, but very little is known about its additives and contaminants that could adversely affect human health. An analytical method was developed to determine organochlorine compounds in henna, as they are still widely used in the areas where henna is grown. Samples were sonicated with n-hexane, extracts cleansed on Florisil sorbent and analysed using gas chromatography with electron capture detection. The overall recoveries were 17-33 % with the extraction RSD 5-21%, while the levels of lindane (gamma-HCH), p,p'-DDT, and p,p'-DDE in henna samples were 7-157 microg kg(-1). The same procedure was successfully applied to analyse black tea samples for the same compounds, and which showed lower contamination. 相似文献
86.
Milosev I Trebse R Kovac S Cör A Campbell P 《Archives of orthopaedic and trauma surgery》2005,125(2):134-141
We describe a case of spontaneous dissociation of the metal inlay from the polyethylene cup of a sandwiched metal-on-metal total hip prosthesis manufactured from Co-28Cr-6Mo SM 21 alloy. The patient, a 51-year-old active woman, started to feel groin pain 50 months postoperatively. The pain progressed after a slight trauma and led to final revision after 66 months in situ. No signs of impingement were observed. The polyethylene cup showed an approximately 2 mm-deep groove in the superior wall, and the head was heavily worn on the lateral side. In addition to the typically observed abrasive wear patterns, several types of severe wear defects were noticed. Extensive metallosis and necrosis were observed histologically. This unusual case of substantial deformation of the head and the cup was presumed to have occurred as a result of the increased friction and consequent high wear of the metal head. 相似文献
87.
Ninichuk V Gross O Reichel C Khandoga A Pawar RD Ciubar R Segerer S Belemezova E Radomska E Luckow B Perez de Lema G Murphy PM Gao JL Henger A Kretzler M Horuk R Weber M Krombach F Schlöndorff D Anders HJ 《Journal of the American Society of Nephrology : JASN》2005,16(4):977-985
Human Alport disease is caused by a lack of the alpha3-, 4-, or 5-chain of type IV collagen (COL4A). Affected humans and COL4A3-deficient mice develop glomerulosclerosis and progressive renal fibrosis in the presence of interstitial macrophages, but their contribution to disease progression is under debate. This question was addressed by treating COL4A3-deficient mice with BX471, an antagonist of chemokine receptor 1 (CCR1) that is known to block interstitial leukocyte recruitment. Treatment with BX471 from weeks 6 to 10 of life improved survival of COL4A3-deficient mice, associated with less interstitial macrophages, apoptotic tubular epithelial cells, tubular atrophy, interstitial fibrosis, and less globally sclerotic glomeruli. BX471 reduced total renal Cll5 mRNA expression by reducing the number of interstitial CCL5-positive cells in inflammatory cell infiltrates. Intravital microscopy of the cremaster muscle in male mice identified that BX471 or lack of CCR1 impaired leukocyte adhesion to activated vascular endothelium and transendothelial leukocyte migration, whereas leukocyte rolling and interstitial migration were not affected. Furthermore, in activated murine macrophages, BX471 completely blocked CCL3-induced CCL5 production. Thus, CCR1-mediated recruitment and local activation of macrophages contribute to disease progression in COL4A3-deficient mice. These data identify CCR1 as a potential therapeutic target for Alport disease or other progressive nephropathies associated with interstitial macrophage infiltrates. 相似文献
88.
The activation of jaw muscles varies with different tasks and must be coordinated to ensure proper function of the masticatory system. The activation patterns might differ in various muscles or over the time course. In order to evaluate the activation patterns and the intermuscular correlation during normal daily activity the electromyograms (EMG) of the superficial and deep masseter, medial pterygoid and digastric muscles were continuously recorded in rabbits and related to activity levels. Muscle use was assessed as the relative time per hour (duty time) during which predefined levels of the peak-EMG of the day were exceeded. Pearson's correlation of duty times was calculated for 6 muscle pairs at various activity levels. The duty times of the muscles differed significantly at levels exceeding 50% of the peak-EMG. The animals exhibited apparent intraday variations of duty times revealing a circadian covariant pattern of muscle use. These variations, however, were different in each individual animal. The activation of pairs of jaw-closing muscles was more highly correlated than that of pairs consisting of a jaw-closing and a jaw-opening muscle. The mutual dependence of hourly muscle activity among jaw-closers and among jaw-closers and jaw-openers varied with the activity level suggesting that those muscle groups might be independently controlled during non-powerful and powerful motor behaviors. 相似文献
89.
Anderson SE Beer KT Banic A Steinbach LS Martin M Friedrich EE Stauffer E Vock P Greiner RH 《AJR. American journal of roentgenology》2005,185(6):1441-1448
OBJECTIVE: The objective of this study was to determine the MRI characteristics of Merkel cell carcinoma, with an emphasis on histologic correlation. MATERIALS AND METHODS: The demographic information about 15 patients from our institution and their MRI examinations were retrospectively reviewed by three musculoskeletal radiologists by consensus for lesion location and intrinsic characteristics. The study group was composed of three women and 12 men who ranged in age from 48 to 87 years, with a mean age of 75 years. Histology results of resected specimens were reviewed in all cases and were correlated with imaging. RESULTS: MRI showed skin thickening, subcutaneous reticular stranding (n = 9, 60%); multiple anatomically aligned subcutaneous soft-tissue masses, representing lymphatic tumor nodules (n = 5, 33%); lymph node enlargement with fine, compressed, retained fatty tissue (n = 5, 33%); nodal necrosis (n = 1); and perifascial and intramuscular metastases (n = 2). Histology confirmed the lymphatic nature of the soft-tissue Merkel cell tumors. CONCLUSION: Patients with Merkel cell tumors may present at imaging with subcutaneous lymphatic reticular stranding, multiple subcutaneous masses, and lymph node metastases. Often there is massive lymph node enlargement with fine, compressed, retained fatty tissue. 相似文献
90.
Dental aesthetics, self-awareness, and oral health-related quality of life in young adults 总被引:5,自引:0,他引:5
The aim of the present study was to explore the putative relationship between dental aesthetics and oral health-related quality of life (OHRQoL), taking into consideration the potential direct and moderating influence of private and public self-consciousness. The subjects of this cross-sectional survey were 148 university students. Dental aesthetics were assessed by means of the aesthetic component (AC) of the Index of Orthodontic Treatment Need (IOTN). OHRQoL was estimated using a modification of the scales 'social appearance concern' and 'appearance disapproval', and a novel dental self-confidence scale. In addition, the private and public self-consciousness scales were used. Two-factor analyses of variance were carried out with high and low levels of dental aesthetics and private and public self-consciousness as the independent variables and the OHRQoL scales as the dependent variables. It was found that dental aesthetics had a direct effect on all OHRQoL scale values. Private self-consciousness was related to social appearance concern, while public self-consciousness was associated with both social appearance concern and appearance disapproval. An interaction effect was identified which showed that the impact of dental aesthetics on social appearance concern was stronger in respondents with high private and public self-consciousness than in low scoring subjects. The findings of the study suggest that minor differences in dental aesthetics may have a significant effect on perceived OHRQoL. This effect was more significant in subjects with high self-consciousness. 相似文献