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81.
The aim of the study was to evaluate the hypothalamus-pituitary-adrenal (HPA) axis in patients (nine males, three females; mean age +/- sem 51 +/- 2 yr) with adult-onset GH deficiency (GHD) due to surgically treated pituitary tumors with preserved HPA function and without evidence of tumor recurrence before and during recombinant human (rh) GH replacement therapy (duration 31 +/- 6 months). HPA function was assessed by urinary free cortisol and morning serum cortisol levels as well as cortisol responses to 1 mug ACTH test (n = 7 patients) or insulin tolerance test (n = 5 patients) before and during rhGH therapy, the cut-off for the diagnosis of hypoadrenalism being a cortisol peak less than 18 microg/dl (<500 nmol/liter) after stimulatory tests. Serum cortisol and urinary free cortisol levels were significantly lower on therapy than before [7.6 +/- 0.8 vs. 11.5 +/- 0.9 microg/dl (208 +/- 22 vs. 317 +/- 24 nmol/liter), P < 0.01, and 19.6 +/- 2.5 vs. 32.2 +/- 3.2 microg per 24 h (54 +/- 7 vs. 89 +/- 9 nmol per 24 h), P < 0.05, respectively], whereas no change in cortisol-binding globulin levels was observed. Cortisol peak after either ACTH test or insulin tolerance test was lower on rhGH therapy than before [15.9 +/- 1.5 vs. 20.2 +/- 1.1 microg/dl (437 +/- 43 vs. 557 +/- 31), P = 0.01, and 13.1 +/- 2.6 vs. 20.4 +/- 1.4 microg/dl (362 +/- 71 vs. 564 +/- 37 nmol/liter), P = 0.03, respectively]. Accordingly, central hypoadrenalism was detected in nine of 11 patients. In conclusion, low GH and IGF-I levels, likely enhancing the conversion of cortisone to cortisol, may mask a condition of central hypoadrenalism. Therefore, the reassessment of HPA function in GHD patients during rhGH therapy is mandatory.  相似文献   
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BackgroundColonoscopy demands a considerable amount of resources, and little is known about its diagnostic yield among inpatients.AimsTo assess indications, diagnostic yield and findings of colonoscopy for inpatients, and to identify risk factors for relevant findings and cancer.MethodsMulticentre, prospective, observational study including 12 hospitals. Consecutive adult inpatients undergoing colonoscopy were evaluated from February through November 2019.Results1,302 inpatients underwent colonoscopy. Diagnostic yield for relevant findings and cancer was 586 (45%) and 112 (8.6%), respectively. Adequate colon cleansing was achieved in 896 (68.8%) patients. Split-dose/same-day regimen was adopted in 847 (65%) patients. Factors associated to relevant findings were age ≥70 years (RR 1.32), male gender (RR 1.11), blood loss (RR 1.22) and adequate cleansing (RR 1.63). Age ≥70 years (RR 2.08), no previous colonoscopy (RR 2.69) and split-dose/same-day regimen (RR 1.59) significantly increased cancer detection. Implementing adequate cleansing and split-dose/same-day regimen in all patients would increase the diagnostic yield for any relevant findings and cancer from 43% to 70% and from 6% to 10%, respectively.ConclusionRelevant colorectal diseases and cancer were frequent among inpatients. Factors associated with detection of relevant findings were identified. Adequate colon cleansing and split-dose/same-day regimen significantly increased colonoscopy diagnostic yield.  相似文献   
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The major drug of abuse among teenagers in the United States continues to be ethanol (EtOH), but use is seen in children as young as nine. In the studies reported here, the impact of EtOH on biologic and hormonal parameters of puberty was assessed in female rats. Rats were fed a liquid diet containing EtOH, pair fed an identical liquid diet containing dextrimaltose instead of EtOH, or fed a liquid diet not containing EtOH ad libitum. Feeding was started at 21, 25, or 28 d of age. EtOH markedly delayed the age at vaginal opening (34.5±0.5 d in controls vs 48.5±2.4 d in EtOH animals; p<0.001), delayed the age at first estrous (40.9±0.6 d in controls vs 61.2±2.6 d in EtOH animals; p<0.001), increased the length of the estrous cycle, and decreased the number of proestrous days. EtOH, concomitant with reduced ovarian and uterine weight, decreased serum estradiol and progesterone. Associated with these changes in ovarian hormones there was a selective increase in follicle-stimulating hormone, but not luteinizing hormone. EtOH consistently reduced insulin-like growth factor-1. In general, EtOH-induced disruption was more severe the younger the animals were at the start of feeding. Opiate receptor blockade with naltrexone completely prevented the EtOH-induced delay in vaginal opening. The impact of EtOH on female puberty is dramatic, is an emerging public health problem, and deserves more study.  相似文献   
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Pituitary - The aim of the present study is to assess the predictive value of the suprasellar volume (SSV) of nonfunctioning pituitary adenomas (NFPAs) for visual field (VF) impairment in order to...  相似文献   
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A simple and robust method able to evaluate and predict, with high accuracy, the optical properties of single and multi-layer nanostructures is presented. The method was implemented using a COMSOL Multiphysics simulation platform and it has been validated by four case studies with increasing numerical complexities: (i) a single thin layer (20 nm) of Ag deposited on a glass substrate; (ii) a metamaterial composed of five bi-layers of Ag/ITO (indium tin oxide), with a thickness of 20 nm each; (iii) a system based on a three-material unit cell (AZO/ITO/Ag), but without any thickness periodicity (AZO stands for Al2O3/zinc oxide); (iv) an asymmetric nanocavity (thin-ITO/Ag/thick-ITO/Ag). A thorough study of this latter configuration reveals peculiar metamaterial effects that can widen the actual scenario in nanophotonic applications. Numerical results have been compared with experimental data provided by real ellipsometric measurements performed on the above mentioned ad hoc fabricated nanostructures. The obtained agreement is excellent, suggesting this research as a valid design approach to realize multi-band metamaterials able to work in a broad spectral range.

Hyper transmission of asymmetric nanocavity metamaterials; a comprehensive optical analysis of multi-layered nanostructures.  相似文献   
90.
Alcoholic liver disease encompasses a broad spectrum of diseases ranging from steatosis steatohepatitis, fibrosis, and cirrhosis to hepatocellular carcinoma. Forty-four per cent of all deaths from cirrhosis are attributed to alcohol. Alcoholic liver disease is the second most common diagnosis among patients undergoing liver transplantation (LT). The vast majority of transplant programmes (85%) require 6 mo of abstinence prior to transplantation; commonly referred to as the “6-mo rule”. Both in the case of progressive end-stage liver disease (ESLD) and in the case of severe acute alcoholic hepatitis (AAH), not responding to medical therapy, there is a lack of evidence to support a 6-mo sobriety period. It is necessary to identify other risk factors that could be associated with the resumption of alcohol drinking. The “Group of Italian Regions” suggests that: in a case of ESLD with model for end-stage liver disease < 19 a 6-mo abstinence period is required; in a case of ESLD, a 3-mo sober period before LT may be more ideal than a 6-mo period, in selected patients; and in a case of severe AAH, not responding to medical therapies (up to 70% of patients die within 6 mo), LT is mandatory, even without achieving abstinence. The multidisciplinary transplant team must include an addiction specialist/hepato-alcohologist. Patients have to participate in self-help groups.  相似文献   
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