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81.
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OBJECTIVES: To determine whether six days recombinant human growth hormone (rhGH) in an abstinent anabolic-androgenic steroid (AAS) group had any cardiovascular and biochemical effects compared with a control group. METHODS: Male subjects (n=48) were randomly divided, using a single blind procedure into two groups: (1) control group (C) n=24, mean+/-SD, age 32+/-11 years; height 1.8+/-0.06m; (2) rhGH using group (0.058IUkg(-1)day(-1)) (GH) n=24, mean+/-SD, age 32+/-9 years; height 1.8+/-0.07m. Physiological responses, anthropometry, arterial pulse wave velocity (APWV), blood pressure (BP), heart rate (HR), peak oxygen uptake (VO(2) peak) and biochemical indices were investigated. RESULTS: Body mass index, fat-free mass index and VO(2) peak significantly increased while body fat significantly decreased within GH (all P<0.017). Insulin like growth factor-I significantly increased within GH (P<0.017) and compared with C (P<0.05). Serum sodium significantly increased (P<0.017) and serum homocysteine, high sensitivity C-reactive protein, thyroid stimulating hormone and tetra-iodothyronine (T(4)), significantly decreased within GH (all P<0.017). T(4) significantly decreased compared with C (P<0.05). Arterial pulse wave velocity, peak and recovery systolic and diastolic BP, significantly decreased compared with C (P<0.05). Resting HR and rate pressure product (RPP) significantly increased compared with C (P<0.05). CONCLUSION: The findings of this study suggest that short term use of rhGH may have beneficial effects on endothelial function and specific inflammatory markers of cardiovascular disease in abstinent AAS users, but may have an adverse effect on the cardiovascular system, as evidenced by the increase in resting RPP.  相似文献   
83.
The biological action and pharmacokinetics of insulin were assessed in nine type 1 (insulin-dependent) diabetic patients before and after 3 months conventional insulin treatment, and in seven age and weight-matched non-diabetic controls, by means of the euglycaemic insulin clamp technique. The mean (+/- S.E.) metabolic clearance rate of insulin, when infused at 1 mU/kg/min, was similar in untreated and treated diabetic patients and in controls (22.7 +/- 2.0, 19.3 +/- 3.8, and 22.9 +/- 3.3 ml/kg/min) but, when infused at 6 mU/kg/min, was greater (p less than 0.01 and less than 0.01) in untreated patients (18.0 +/- 2.5 ml/kg/min) than in treated patients (11.5 +/- 1.4 ml/kg/min) and controls (12.7 +/- 1.3 ml/kg/min). Insulin-mediated glucose disposal was reduced (p less than 0.01 and less than 0.01) at insulin infusion rates 1 and 6 mU/kg/min in untreated patients (18.5 +/- 1.9 and 33.8 +/- 4.5 mumol/kg/min) when compared with controls (35.8 +/- 3.4 and 62.0 +/- 4.7 mumol/kg/min) and was improved (p less than 0.01 and less than 0.01) following insulin treatment (36.1 +/- 4.6 and 64.8 +/- 4.2 mumol/kg/min). Daily insulin requirement fell by 33% following 3 months insulin treatment with improvement in mean HbA1 from 16.3 +/- 0.7 to 8.2 +/- 0.4%, but without significant increase in endogenous insulin secretion. The 'honeymoon phenomenon', which has traditionally been attributed exclusively to resurrection of endogenous insulin release, may also be related to normalization of insulin action following institution of insulin treatment.  相似文献   
84.
We describe our 9-year experience with lectin-treated T-cell-depleted haplocompatible parental bone marrow transplantation (BMT) for 24 patients with severe combined immunodeficiency disease (SCID). Nineteen of 21 evaluable patients had T-cell engraftment; 2 of 11 patients tested had B-cell and monocyte engraftment. Fourteen of 24 (58%) patients are alive 7 months to 9.8 years post-BMT. Seventeen of 24 patients received pretransplant conditioning with chemotherapy and/or total body irradiation, and 8 of 24 received more than one transplant. Patients who received conditioning had a survival rate of 61% versus 57% for those who received no conditioning. None received graft-versus- host disease (GVHD) prophylaxis and no patient had acute or chronic GVHD greater than grade I. Kinetics and follow-up of immune recovery were analyzed in 14 patients who are greater than 1 year from transplant. Half of the patients showed evidence of T-cell function by 3 months and normal T-cell function by 4 to 7 months post-BMT. On average, T-cell numbers and subsets became normal 10 to 12 months posttransplant. Recovery of B-cell function was more delayed, although in most patients B-cell numbers and IgM levels were normal by 12 months post-BMT. B-cell function, as determined by isohemagglutinin titers or specific antibodies to pneumococcal polysaccharide, keyhole limpet hemocyanin, or tetanus toxoid, became normal in 10 of 14 patients 2 to 8 years post-BMT. Seven of the 14 are off gammaglobulin therapy. Production of isohemagglutinins tended to predict recovery of antibody response to pneumococcal polysaccharide (P < .064). Based on these results, we believe that haplocompatible BMT is an effective, curative treatment for patients with SCID who lack an HLA-matched related donor.  相似文献   
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In the cat or primate primary visual cortex (V1), normal vision corresponds to a state where neural excitation patterns are driven by external visual stimuli. A spectacular failure mode of V1 occurs when such patterns are overwhelmed by spontaneously generated spatially self-organized patterns of neural excitation. These are experienced as geometric visual hallucinations. The problem of identifying the mechanisms by which V1 avoids this failure is made acute by recent advances in the statistical mechanics of pattern formation, which suggest that the hallucinatory state should be very robust. Here, we report how incorporating physiologically realistic long-range connections between inhibitory neurons changes the behavior of a model of V1. We find that the sparsity of long-range inhibition in V1 plays a previously unrecognized but key functional role in preserving the normal vision state. Surprisingly, it also contributes to the observed regularity of geometric visual hallucinations. Our results provide an explanation for the observed sparsity of long-range inhibition in V1--this generic architectural feature is an evolutionary adaptation that tunes V1 to the normal vision state. In addition, it has been shown that exactly the same long-range connections play a key role in the development of orientation preference maps. Thus V1's most striking long-range features--patchy excitatory connections and sparse inhibitory connections--are strongly constrained by two requirements: the need for the visual state to be robust and the developmental requirements of the orientational preference map.  相似文献   
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Alpha-mannosidosis is a rare lysosomal storage disease. Hematopoietic SCT (HSCT) is usually recommended as a therapeutic option though reports are anecdotal to date. This retrospective multi institutional analysis describes 17 patients that were diagnosed at a median of 2.5 (1.1-23) years and underwent HSCT at a median of 3.6 (1.3-23.1) years. In all, 15 patients are alive (88%) after a median follow-up of 5.5 (2.1-12.6) years. Two patients died within the first 5 months after HSCT. Of the survivors, two developed severe acute GvHD (>=grade II) and six developed chronic GvHD. Three patients required re-transplantation because of graft failure. All 15 showed stable engraftment. The extent of the patients' developmental delay before HSCT varied over a wide range. After HSCT, patients made developmental progress, although normal development was not achieved. Hearing ability improved in some, but not in all patients. We conclude that HSCT is a feasible therapeutic option that may promote mental development in alpha-mannosidosis.  相似文献   
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