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Background  

Development of accurate therapeutic approaches to salivary gland neoplasms depends on better understanding of their molecular pathogenesis. Tumour growth is regulated by the balance between proliferation and apoptosis. Few studies have investigated apoptosis in salivary tumours relying almost exclusively on immunohistochemistry or TUNEL assay. Furthermore, there is no information regarding the mRNA expression profile of apoptotic genes in salivary tumors. Our objective was to investigate the quantitative expression of BCL-2 (anti-apoptotic), BAX and Caspase3 (pro-apoptotic genes) mRNAs in salivary gland neoplasms and examine the association of these data with tumour size, proliferative activity and p53 staining (parameters associated with a poor prognosis of salivary tumours patients).  相似文献   
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ObjectivesTo determine the impact of energy density on diet quality and anthropometric proxy measures for central body fat in young Spaniards.MethodsData were obtained from a representative national sample of 2513 young Spaniards aged 10 to 24 y. Dietary assessment was performed with a 24-h recall. Adherence to the Mediterranean diet was measured by the KIDMED index. Reduced rank regression analysis was used to identify energy-density dietary patterns. Waist circumferences and height were measured.ResultsPastries and sausages showed the strongest loading for the dietary energy density factor score (DED-FS), with fruits and vegetables at the opposite end of the scale. Multiple linear regression analysis showed a positive association (P < 0.01) of dietary energy density (DED) and the DED-FS with waist circumferences regressed on height and age (WCheight+age) and waist-to-height ratio (WHtR). The adjusted odds ratio for elevated WCheight+age and WHtR increased across quartile distribution of DED (P < 0.001) and DED-FS (P < 0.05). Diet quality characterized by the KIDMED index was negatively associated (P < 0.001) with DED and the DED-FS.ConclusionsHigher DED is a risk for increased central fat distribution and is associated with low adherence to the Mediterranean diet.  相似文献   
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Two sibling Drosophila species dramatically divergent in longevity, Drosophila buzzatii and D. koepferae, were examined for possible effects of both developmental culture medium and dietary composition (DC) on longevity. Longevity was greatly increased in the longer lived D. buzzatii when flies were reared and fed on a rich-in-nutrient and cactus-based culture (R-CBC) as compared to longevity in a poor nutrient culture (PNC). In D. buzzatii, life span was further increased by exposing flies to short periods of a poor-in-nutrient and cactus-based culture (P-CBC). In contrast, variation in the here used nutrient composition did not change life span in the shorter lived D. koepferae, as longevity in this species did not differ among R-CBC, P-CBC and PNC cultures. Hormesis is a plausible explanation for the beneficial biological effects against aging arising from brief exposure to a lowed calorie food source in D. buzzatii. This study shows that genetic variation between closely related species is substantial for dietary effects on longevity.  相似文献   
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Toksoz  D; Dexter  TM; Lord  BI; Wright  EG; Lajtha  LG 《Blood》1980,55(6):931-936
The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator).  相似文献   
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A young woman with a history of classic migraine suffered a large cerebellar infarction. Comprehensive evaluation did not disclose any potential causes for the stroke and she had no other risk factors. Transcranial Doppler (TCD) was useful in identifying vasospasm of the vertebral arteries. Following treatment with propranolol, angiography and repeat TCD revealed resolution of the vasospastic disorder. TCD is a useful noninvasive tool in detecting vasospasm associated with ischemic lesions in certain patients with migraine.  相似文献   
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OBJECTIVE: To undertake a multicentre epidemiological study reflecting acromegaly in Spain. DESIGN: Voluntary reporting of data on patients with acromegaly to an online database, by the managing physician. METHODS: Data on demographics, diagnosis, estimated date of initial symptoms and diagnosis, pituitary imaging, visual fields, GH and IGF-I concentrations (requested locally), medical, radiotherapy and neurosurgical treatments, morbidity and mortality were collected. RESULTS: Data were included for 1219 patients (60.8% women) with a mean age at diagnosis of 45 years (s.d. 14 years). Reporting was maximal in 1997 (2.1 cases per million inhabitants (c.p.m.) per year); prevalence was globally 36 c.p.m., but varied between 15.7 and 75.8 c.p.m. in different regions. Of 1196 pituitary tumours, most were macroadenomas (73%); 81% of these patients underwent surgery, 45% received radiotherapy and 65% were given medical treatment (somatostatin analogues in 68.3% and dopamine agonists in 31.4%). Cures (GH values (basal or after an oral glucose tolerance test) <2 ng/ml, normal IGF-I, or both) were observed in 40.3% after surgery and 28.2% after radiotherapy. Hypertension (39.1%), diabetes mellitus (37.6%), hypopituitarism (25.7%), goitre (22.4%), carpal tunnel syndrome (18.7%) and sleep apnoea (13.2%) were reported as most frequent morbidities; 6.8% of the patients had cancer (breast in 3.1% of the women and colon in 1.2% of the cohort). Fifty-six patients died at a mean age of 60 years (s.d. 14 years), most commonly of a cardiovascular cause (39.4%); mortality was greater in patients given radiotherapy (hazard ratio 2.29; 95% confidence interval 1.03 to 5.08; P=0.026), and in those in whom GH and IGF-I concentrations were never normal (P<0.001). CONCLUSIONS: This acromegaly registry offers a realistic overview of the epidemiological characteristics, treatment outcome and morbidity of acromegaly in Spain. As active disease and treatment with radiotherapy are associated with an increase in mortality, efforts to control the disease early are desirable.  相似文献   
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