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101.
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OBJECTIVE: To investigate the association between physical performance measures and bone mineral density (BMD) in older women. DESIGN: Cross-sectional analysis. SETTING: University research laboratory. PARTICIPANTS: Healthy postmenopausal women (N=116; mean age +/- standard deviation, 68.3+/-6.8y) in self-reported good health who were not taking medications known to affect bone, including hormone replacement therapy. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Anthropometrics and BMD of the hip, spine, whole body, and forearm. Physical performance measures included normal and brisk 8-m gait speed, normal step length (NSL), brisk step length (BSL), timed 1-leg stance (OLS), timed sit-to-stand (STS), and grip strength. RESULTS: NSL, BSL, normal gait speed, brisk gait speed, OLS, and grip strength correlated significantly with several skeletal sites ( r range, .19-.38; P <.05). In multiple regression models containing body mass index, hours of total activity, total calcium intake, and age of menarche, NSL, BSL, normal and brisk gait speeds, OLS, and grip strength were all significantly associated with BMD of various skeletal sites (adjusted R 2 range, .11-.24; P <.05). Analysis of covariance showed that subjects with longer step lengths and faster normal and brisk gait speeds had higher BMD at the whole body, hip, and spine (brisk speed only). Those with a longer OLS had greater femoral neck BMD, and those with a stronger grip strength had greater BMD in the whole body and forearm ( P <.05). STS was not related to any skeletal site. CONCLUSIONS: Normal and brisk gait speed, NSL, BSL, OLS, and grip strength are all associated with BMD at the whole body, hip, spine, and forearm. Physical performance evaluation may help with osteoporosis prevention and treatment programs for postmenopausal women when bone density scores have not been obtained or are unavailable.  相似文献   
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This review explains the physiological involvement of calcium in overweight/obesity (as it is understood now) and presents some of the studies where this role has been documented, as well as those reporting no effect of Ca on body weight/composition. Based on much of the presently reported data, Ca and even more so dairy foods, might help in weight reduction/maintenance when combined with energy-restricted diet. The scientific community is in agreement that there is a pressing need for large clinical trials to assess the effect of Ca on weight reduction and to investigate whether weight loss could be achieved easier with Ca supplements or dairy products. It has yet to be learned what amount of Ca would be optimal for those purposes and what influence, if any, an individual's current Ca intake and existing weight might play. Additionally, it is still hard to pinpoint which component(s) in dairy foods have a role in weight reduction and whether they act alone or in synergism with Ca. Considering the overwhelming prevalence of overweight/obesity and consequences to population health and economic burden it entails, it is of crucial importance to develop strategies to curtail the problem of obesity from all fronts and the one involving Ca seems quite promising. However, more research in this area is necessary.  相似文献   
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Hemangiopericytoma is a rare soft tissue tumor originating from contractile pericapillary pericytes. To address the issue of molecular genetic events that participate in genesis and progression of hemangiopericytoma we analyzed insulin-like growth factor (IGF) II and IGF I receptor in 29 tumors collected from a human tumor bank network. Seven of these tumors were associated with severe hypoglycemia; six were retroperitoneal and one was located in the leg. Of 22 tumors tested 12 (54.5%) exhibited IGF II mRNA, while almost 90% (17 of 19) of hemangiopericytomas exhibited IGF I receptor mRNA. Sera from some patients whose tumors expressed IGF II mRNA contained elevated levels of IGF II. Removal of the tumor eliminated most of the IGF II immunoreactivity from the sera. The potential role of IGF II as a growth-promoting factor was examined on three malignant primary hemangiopericytoma cell cultures. Extracellular addition of IGF II significantly enhanced cell proliferation in a dose-dependent manner. Antisense oligodeoxynucleotides that specifically inhibit IGF II mRNA, at a concentration of 40 or 80 micrograms/ml, inhibited the growth of hemangiopericytoma cells significantly, by 40%. Simultaneous administration of antisense deoxyoligonucleotides to both IGF II and IGF I receptor inhibited tumor cell proliferation by even 80%. Our data suggest that tumor cells produce IGF II, and that this in turn stimulates their proliferation by autocrine mechanisms.  相似文献   
105.
Yarrowia lipolytica yeast was grown batchwise on n-hexadecane as the carbon and energy source. Two cerebroside species were quantitatively isolated from sphingolipid fractions of total lipids by a combination of column chromatography and preparative high-performance thin-layer chromatography. The cerebroside content accounted for 1.3% of the total cell lipids. Glucose was detected as the sole sugar constituent in cerebrosides. The fatty acid composition of cerebrosides was characterized by a high proportion of hydroxylated long-chain saturated fatty acids. The major fatty acids were h16:0 and 16:0. The long-chain bases composition shows a preponderance of trihydroxy bases and a small amount of dihydroxy bases. The striking finding was a high proportion of 19-phytosphingosine.  相似文献   
106.
Conjunctival melanoma is a rare but sight and life threatening malignancy. It accounts for 2%–5% of all ocular tumours and 5%–7% of all ocular melanomas with an incidence of 0.2–0.8 per million in the Caucasian population with rare cases reported in the non-Caucasians. In recent decades the incidence of uveal melanoma has been relatively stable whilst conjunctival and cutaneous melanoma have shown increasing incidence which may be connected to the result of environmental exposure to ultraviolet light. The dissimilarity in incidence between light and dark pigmented individuals observed in conjunctival melanomas compared to uveal and cutaneous melanomas may be related to differences in their histological structures and genetic profile. Recent molecular biological studies support the fact that each type of melanoma undergoes its own molecular changes and has characteristic biological behaviour. Further studies are required for each type of melanoma in order to ascertain their individual etiology and pathogenesis and based on this knowledge develop relevant preventative and treatment procedures.  相似文献   
107.
There are a number of reports on collision occurrence of non-hematologic cancers and Non-Hodgkin's lymphoma (NHL) and multiple myeloma. In this report we present a case of patient with immunoproliferative disease, extramedullary plasmocytoma and NHL-lymphoplasmocytoid lymphoma (LPL) and squamous cell carcinoma of the lung. After diagnosis of extramedullary plasmocytoma cytostatic therapy was commenced and the patient was well. Five years after patient was clinically worse and diagnostic evaluation this time revealed lymphoplasmocytoid cells in bone marrow. Five months later malignant morphologically undifferentiated cells were found in bone marrow which were by immunocytochemistry established as CD38 positive. After the patient's death, disseminated NHL-LPL and squamous cell carcinoma of lung was confirmed. In the report, we compared clinical course and diagnostic findings of our patient with literature data. We have also discussed the possible relationship of multiple B-cell lymphoid tumors and squamous cell carcinoma concluding that multidiscplinary diagnostic tools are essential not only for carcinoma diagnosis and follow-up, but also for further understanding of carcinogenesis.  相似文献   
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Bombesin receptor subtype-3 (BRS-3) is an orphan G protein-coupled receptor implicated in the regulation of energy homeostasis. Here, we report the biologic effects of a highly optimized BRS-3 agonist, (2S)-1,1,1-trifluoro-2-[4-(1H-pyrazol-1-yl)phenyl]-3-(4-{[1-(trifluoromethyl)cyclopropyl]methyl}-1H-imidazol-2-yl)propan-2-ol (MK-5046). Single oral doses of MK-5046 inhibited 2-h and overnight food intake and increased fasting metabolic rate in wild-type but not Brs3 knockout mice. Upon dosing for 14 days, MK-5046 at 25 mg · kg(-1) · day(-1) reduced body weight of diet-induced obese mouse by 9% compared with vehicle-dosed controls. In mice, 50% brain receptor occupancy was achieved at a plasma concentration of 0.34 ± 0.23 μM. With chronic dosing, effects on metabolic rate, rather than food intake, seem to be the predominant mechanism for weight reduction by MK-5046. The compound also effectively reduced body weight in rats and caused modest increases in body temperature, heart rate, and blood pressure. These latter effects on temperature, heart rate, and blood pressure were transient in nature and desensitized with continued dosing. MK-5046 is the first BRS-3 agonist with properties suitable for use in larger mammals. In dogs, MK-5046 treatment produced statistically significant and persistent weight loss, which was initially accompanied by increases in body temperature and heart rate that abated with continued dosing. Our results demonstrate antiobesity efficacy for MK-5046 in rodents and dogs and further support BRS-3 agonism as a new approach to the treatment of obesity.  相似文献   
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