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Analysis of the function of the nervous system, based on clinical, neurological, and psychological studies in 78 patients with generalized periodontitis, revealed central regulation disorders without signs of organic lesions of the brain in 76% patients. The authors claim that stress and a high level of personal anxiety may be responsible for the development of these disorders, which was confirmed by the results of psychological testing.  相似文献   
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Iron deficiency can be caused not only by diets deficient in iron but by poor absorption of available dietary iron. Extrinsically tagging foods with radioiron allows the exact measurement of iron absorbed from heme and nonheme iron foods. It has furthered the study of the effect of enhancers and inhibitors of iron absorption. As a result, we have a greater understanding of why iron deficiency and iron deficiency anemia are prevalent in populations of low socioeconomic status and of which food vehicles and iron compounds are most suitable for iron fortification.  相似文献   
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Laparoscopic surgery has gained much interest since its advent the late eighties. A 36-year-old patient underwent laparoscopic appendicectomy via the transumbilical route. She was rehospitalized three times thereafter for subumblical pain. At day +48, an abscess was evacuated at the point of the umbilical trocar insertion. This hour-glass shaped abscess had a preperitoneal and subcutaneous localization, blocked by the epiploic reaction. The infection this patient developed is an unusual clinical finding as pain was localized at a distance. The umbilical site and the preperitoneal subcutaneous nature of the abscess are also unusual. This case emphasizes the gravity of post-operative abscess of the abdominal wall and the necessity for adequate prophylaxy.  相似文献   
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We have previously shown that the tumor suppressor gene for hepatocellular carcinoma (HCC) without cirrhosis may be located on chromosome 5q35-qter. In this study, we analyzed nine cases of primary HCC without cirrhosis using probes from the MCC and APC genes, which are in the region 5q21-22. None of the informative cases had allele loss detected by these probes, whereas the probe lambda MS8 for the region 5q35-qter showed allele loss in six out of six informative cases. The results confirm that the putative tumor suppressor gene for HCC without cirrhosis on chromosome 5q is distinct from the MCC and APC genes.  相似文献   
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For environmental considerations, the substitution of the conventionally used oil-based grinding fluids has nowadays become strongly recommended. Although several alternatives have been proposed, cryogenic cooling by liquid nitrogen is the non-polluting coolant that has been given relatively more attention because of its very low temperature. In this investigation, in order to contribute to developing this promising cooling mode, its beneficial effects on the ground surface integrity of the AISI 304 stainless steel and their consequences on the fatigue lifetime are explored. Results of this investigation show that grinding under cryogenic cooling mode generates surfaces with lower roughness, less defects, higher work hardening and less tensile residual stresses than those obtained on surfaces ground under oil-based grinding fluid. These surface enhancements result into substantial improvements in the fatigue behaviour of components ground under this cooling mode. An increasing rate of almost 15% of the endurance limit at 2 × 106 cycles could be realized. SEM analyses of the fatigue fracture surfaces have shown that the fatigue cracks observed on the specimens ground under cryogenic cooling are shorter (i.e., 30-50 μm) than those generated under oil-based cooling mode (i.e., 150-200 μm). The realized improvements in the surface integrity and in the fatigue behaviour are thought to be related to the reduction of the grinding zone temperature observed under cryogenic cooling, as no significant differences between the grinding force components for both cooling modes have been observed.  相似文献   
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