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91.
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93.
The aim of this study was to determine the clinical impact of whole body positron emission tomography (FDG PET) to detect clinically silent metastases in the follow-up of patients with high risk melanoma. FDG PET was performed to 30 asymptomatic melanoma patients (AJCC stage IIB-IIIC) 7-24 months after the primary surgery and sentinel node biopsy. FDG PET was able to detect six of seven recurrences, constituting 20% of all study patients. One patient presented with a negative FDG PET finding at the very first scanning, but was positive later in a repeated scan after manifestation of palpable mass in the axilla. The positive PET finding had an impact on treatment decisions in every case: three patients underwent surgical resection and four patients received chemotherapy or interferon. The mean follow-up time was 27 months (range, 12-48 months) and during that time the other 23 patients with true negative FDG PET were disease-free. One of the seven recurrences was in remission after surgical metastasectomy. In conclusion, whole body FDG PET is a valuable follow-up tool in high risk melanoma to diagnose recurrences and to select the patients, who are suitable for surgical metastasectomy.  相似文献   
94.
An international collaborative health screening project was undertaken to stimulate interest in child health education, to study feasibility of health screening in young children from diverse cultures, and to compare the distribution of chronic disease risk factors among 15 countries. Data for the 13-year-old participants showed that risk factors defined by cholesterol greater than 180 mg/dl, systolic blood pressure greater than 130 mm Hg, and daily or occasional smoking were present, to varying degrees, in children from each country. We found no relationship between obesity and cholesterol or blood pressure for these children. The acceptability of the screening, the children's enjoyment in participation, and the prevalence of risk factors at this young age lead to the conclusion that school-based health education programs should be initiated during childhood.  相似文献   
95.
The aim of this pilot study was to determine the postoperative blood perfusion (BF(PET)) and perfusion heterogeneity (BF(PET) HG) in free microvascular breast reconstruction flap zones with positron emission tomography (PET). Regional BF(PET) and BF(PET) HG of the adipose tissue in medial, central, and lateral parts of 13 free flaps were assessed on the first postoperative morning with PET using oxygen-15-labeled water ([(15)O]H(2)O) in 12 patients undergoing breast reconstruction with a deep inferior epigastric perforator (DIEP) or a transverse rectus abdominis muscle (TRAM) flap. The mean BF(PET) values did not differ between DIEP and TRAM flaps (P = 0.791). The mean BF(PET) values were higher in zone III compared with zone I (P = 0.024). During follow-up, fat necrosis was identified in three patients in the medial part (zone II) of the flap. However, the adipose tissue BF(PET) assessed on the first postoperative day from all zones of the flap using PET with radiowater was normal. The BF(PET) HG was higher in the control side (i.e., in the healthy breast tissue) compared with the flap (P = 0.042). The BF(PET) HG was lower in zone III than in zone I (P = 0.03) and in zone II (P < 0.001). In this pilot study, PET was used for the first time for studying the adipose tissue perfusion in different zones in free flaps in a clinical setup, finding that the mean BF(PET) values did not differ between DIEP and TRAM flaps, and that zone II was sometimes not as well perfused as zone III supporting revisited zone division.  相似文献   
96.
OBJECTIVE: The purpose of this study was to investigate whether smoking reduces the effects of transdermal estrogen replacement therapy on bone. STUDY DESIGN: One hundred forty-eight women (0.5-5 years after menopause, aged 46-58 years) completed the study. Smokers were assigned randomly to receive either 1.0 mg (n=32 women) or 1.5 mg (n=31 women) of transdermal estradiol in gel daily, and nonsmokers (n=46 women) were assigned to receive 1.0 mg of transdermal estradiol for 2 years. The control group consisted of 17 smokers and 22 nonsmokers. Bone mineral density was measured by dual-energy x-ray absorptiometry. Bone turnover was assessed by measurements of urinary aminoterminal telopeptide of type I collagen and serum aminoterminal propeptide of type I procollagen. RESULTS: Lumbar spine bone mineral density increased similarly in smoking (+3.6%) and nonsmoking (+2.6%) estrogen users (P<.0001 to a decrease of 2.5% in the control group). Femoral neck bone mineral density increased 2.2% to 2.4% in smoking and nonsmoking estrogen users but decreased 0.2% in control subjects (P<.05). Urinary aminoterminal telopeptide of type I collagen decreased similarly in all estrogen-using groups (P<.05 to control group), but serum aminoterminal propeptide of type I procollagen decreased more in smoking than in nonsmoking estrogen users (P=.006). Serum 25-hydroxyvitamin D was 20% lower (P=.004) in smokers than in nonsmokers. CONCLUSION: Transdermal estrogen treatment protects smoking women as effectively as nonsmokers from osteoporosis. Smoking worsens the vitamin D state of postmenopausal women.  相似文献   
97.
Differences in breastfeeding, other milk feeding and complementary feeding patterns were evaluated in infants at increased genetic risk with and without maternal type 1 diabetes (T1D). The Trial to Reduce IDDM in the Genetically at Risk is an international nutritional primary prevention double‐blinded randomized trial to test whether weaning to extensively hydrolyzed vs. intact cow's milk protein formula will decrease the development of T1D‐associated autoantibodies and T1D. Infant diet was prospectively assessed at two visits and seven telephone interviews between birth and 8 months. Countries were grouped into seven regions: Australia, Canada, Northern Europe, Southern Europe, Central Europe I, Central Europe II and the United States. Newborn infants with a first‐degree relative with T1D and increased human leukocyte antigen‐conferred susceptibility to T1D were recruited. A lower proportion of infants born to mothers with than without T1D were breastfed until 6 months of age in all regions (range, 51% to 60% vs. 70% to 80%). Complementary feeding patterns differed more by region than by maternal T1D. In Northern Europe, a higher proportion of infants consumed vegetables and fruits daily compared with other regions. Consumption of meat was more frequent in all European regions, whereas cereal consumption was most frequent in Southern Europe, Canada and the United States. Maternal T1D status was associated with breastfeeding and other milk feeding patterns similarly across regions but was unrelated to the introduction of complementary foods. Infant feeding patterns differed significantly among regions and were largely inconsistent with current recommended guidelines.  相似文献   
98.
This study aimed to evaluate the associations among serum 17beta-estradiol (E2), testosterone (T), sex hormone-binding globulin (SHBG), bone geometric properties, and mineral density in 248 healthy girls between the ages of 10 and 13 yr old. The left tibial shaft was measured by peripheral quantitative computed tomography (Stratec XCT-2000; Stratec Medizintechnik, GmbH, Pforzheim, Germany). The cortical bone and marrow cavity areas were expressed as proportions of the total tibial cross-sectional area (CSA). Cortical thickness and total volumetric bone mineral density (vBMD) were also determined. These tibial geometric and densitometric measures were correlated against the serum sex hormone concentrations after controlling for age and body size. The results showed that E2 was negatively associated with marrow cavity proportion (r = -0.19, P = 0.003) and positively associated with cortical proportion and thickness and with total vBMD (r = 0.26, P < 0.001; r = 0.25, P < 0.001; and r = 0.23, P < 0.001, respectively). However, T was not associated with these bone variables. On the other hand, SHBG was positively associated with marrow cavity proportion (r = 0.17, P = 0.007) and negatively associated with cortical proportion and thickness and with total vBMD (r = -0.14, P = 0.029; r = -0.16, P = 0.010; and r = -0.18, P = 0.005, respectively). Total bone CSA did not correlate with E2, T, or SHBG. These results suggest that E2 has a positive effect on bone geometric and densitometric development by suppressing bone turnover at the endocortical surface during the early pubertal period, that SHBG plays an opposite role to E2, and that T has no detectable effect.  相似文献   
99.
Interaction of intercellular adhesion molecules (ICAMs) with their receptors has a key role in normal leucocyte adhesion and migration, whereas in leukaemia this has not been well established. In this study, we have evaluated the roles of different adhesion molecules in normal and leukaemia cell extravasation in a novel organotypic model for vessel wall and measured plasma ICAM-1 and -2 levels in acute leukaemia patients at diagnosis and during chemotherapy. We found that both normal mononuclear cells and blast cells from acute leukaemia patients, as well as retinoic acid-treated promyelocytic leukaemia cells, rapidly extravasated through endothelial cell layers into the underlying collagen matrix. ICAM-1 antibody prevented the extravasation, while antibodies to other adhesion molecules showed little (CD18, ICAM-2) or no inhibition (CD11a and ICAM-3). Soluble ICAM-1 (sICAM-1) protein had no effect. We also observed increased plasma sICAM-1 and -2 levels in leukaemia patients and found that they correlated only weakly with the white blood cell count. No correlation was found between sICAM-1 or -2 levels and the response to therapy. Although elevated sICAM-2 levels decreased rapidly during chemotherapy, sICAM-1 levels did not. Because sICAM-1 protein had no effect on leukaemia cell extravasation in vitro, it is probable that the increased plasma sICAM-1 levels in leukaemia patients may not play a role in leukaemia cell infiltration. However, as we showed that ICAM-1 mediated leukaemia cell extravasation on the cell surface, it is possible that cellular ICAM-1 has an important role in disease progression.  相似文献   
100.
BACKGROUND: Upregulation of proinflammatory endothelial cell adhesion molecules and decreased bioactivity of endothelial nitric oxide (NO) are important in the pathogenesis of atherosclerosis. We investigated the effects of co-infection with Chlamydia pneumoniae and Helicobacter pylori on these two events in apoE-KO mice. METHODS: Thirty-two apoE-KO mice, 8 weeks old, were equally divided into 4 groups. The first 2 groups were infected with either C. pneumoniae or H. pylori, while the 3rd group was infected with both C. pneumoniae and H. pylori. Mice from the 4th group and 4 wild-type mice served as controls. Thoracic and abdominal aortas were harvested after 10 weeks, and staining for vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 was analyzed by immunocytochemistry. The endothelial vasomotor responses of thoracic aortas to methacholine were studied in organ chambers in the absence and presence of L-NAME. The plasma levels of nitrate/nitrite were measured. RESULTS: Staining for VCAM-1 was more intense at the branching sites of aortas from mice with co-infection than in mono-infected or noninfected apoE-KO mice. The relaxation responses to methacholine and the plasma levels of nitrate/nitrite were significantly less in the co-infected group than in the other groups (p < 0.05). CONCLUSION: Co-infection of apoE-KO mice with C. pneumoniae and H. pylori seems to be associated with impaired bioactivity of endothelial NO and increased expression of VCAM-1 at branching sites. The findings may suggest an additive interaction of these pathogens in atherogenesis.  相似文献   
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