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BACKGROUND Metabolic disturbances including changes in serum calcium,magnesium or phosphate(P) influence the prevalence of type 2 diabetes mellitus(DM).We assessed the importance of serum P in elderly patients with type 2 DM vs nondiabetes mellitus(non-DM) in relation to renal function.AIM To determine the association between serum P and serum glucose or insulin resistance in diabetic and non-diabetic patients.METHODS One hundred-ten subjects with a mean age of 69.02±14.3 years were enrolled.Twenty-nine of the participants had type 2 DM(26.4%).The incidence of hypertension,smoking and receiving vitamin D(vitD) derivates were recorded.The participants were classified by both estimated glomerular filtration rate(eGFR) and albuminuria categories according to the Kidney Disease Improving Global Outcomes 2012 criteria.RESULTS We divided the patients in two groups according to the P cut-off point related to DM value.A comparison between high and low P showed that body mass index30.2±6.3 vs 28.1±4.6(P=0.04),mean glucose 63.6 vs 50.2(P=0.03),uric acid 6.7±1.6 vs 6.09±1.7(P=0.05),mean intact-parathyroid hormone 68.06 vs 47.4(P=0.001),systolic blood pressure 147.4±16.7 vs 140..2±16.1(P=0.02),mean albuminuria 63.2 vs 50.6(P=0.04) and eGFR 45.6±22.1 vs 55.4±21.5(P=0.02)were significantly different.χ~2 tests showed a significant association between high P and DM,hypertension,receiving vitD,smoking and eGFR stage(χ~2=6.3,P=0.01,χ~2=3.9,P=0.03,χ~2=6.9,P=0.009,χ~2=7.04,P=0.01 and χ~2=7.36,P=0.04,respectively).The adjusted model showed that older age,female gender and increased body mass index were significant predictors of type 2 DM when entering the covariates.CONCLUSION High serum P contributes to vascular and metabolic disturbances in elderly patients with type 2 DM and renal impairment.  相似文献   
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Introduction  

Positive end-expiratory pressure (PEEP)-induced lung derecruitment can be assessed by a pressure–volume (P–V) curve method or by lung computed tomography (CT). However, only the first method can be used at the bedside. The aim of the study was to compare both methods for assessing alveolar derecruitment after the removal of PEEP in patients with acute lung injury or acute respiratory distress syndrome.  相似文献   
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BACKGROUND: Early, rapid bone loss and fractures after cardiac transplantation are well-documented complications of steroid administration; therefore, we undertook this study on the effects of long-term calcitonin on steroid-induced osteoporosis. METHODS: Twenty-three heart transplant recipients on maintenance immunosuppression with cyclosporine, mycophenolate mofetil and prednisone were retrospectively studied. All patients received long-term prophylactic treatment with elemental calcium and vitamin D. Twelve (52.2%) patients also received long-term intranasal salmon calcitonin, whereas 11 (47.8%) received none. Bone mineral density and vertebral fractures were assessed at yearly intervals. Statistical comparisons between each group's bone loss during the first year and in the early (1 to 3 years), intermediate (4 to 6 years) and late (7+ years) post-transplantation periods were done. RESULTS: Lumbar spine bone loss was significant during the early follow-up period in the group not receiving calcitonin (0.744 +/- 0.114 g/cm(2) vs 0.978 +/- 0.094 g/cm(2) [p = 0.002]). The calcitonin group showed bone mineral density (BMD) levels within normal average values throughout the study period. BMD increased in the no-calcitonin group during the intermediate (4 to 6 years) and late (7+ years) follow-up periods, with values approaching normal average and no significant difference between the 2 groups (0.988 +/- 0.184 g/cm(2) vs 0.982 +/- 0.088 g/cm(2) [p = 0.944] and 0.89 +/- 0.09 g/cm(2) vs 1.048 +/- 0.239 g/cm(2) [p = 0.474], respectively). CONCLUSIONS: Prophylactic treatment with intranasal salmon calcitonin prevents rapid bone loss associated with high-dose steroids early after cardiac transplantation. Long-term administration does not seem warranted in re-establishing BMD.  相似文献   
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The pharmacokinetics and metabolism of 4-demethoxydaunorubicin (idarubicin, IDA) were studied in 21 patients with advanced cancer after i.v. (12 mg/m2) and oral (30-35 mg/m2) treatment according to a balanced crossover design. Patients were divided into four groups: subjects who showed normal liver and kidney function (group N), those who presented with normal kidney function and liver metastases (group L), those with kidney dysfunction (creatinine clearance, less than or equal to 60 l/h; group R), and those with both liver and kidney dysfunction (group LR). Five patients showed variations in liver or kidney function after the first treatment and were considered to be nonevaluable for the crossover study but evaluable for the liver/kidney function study; some of them appeared in different groups for the i.v. as opposed to p.o. treatments. After i.v. administration, IDA plasma levels followed a triphasic decay pattern. The main metabolite observed in all patients was the 13C-reduced compound (IDAol), which attained plasma levels 2-12 times higher than those of the parent compound. IDA pharmacokinetics was not dependent on the presence of liver metastases but was related to the integrity of kidney function. Analysis of variance indicated a significant correlation between IDA plasma clearance and creatinine clearance; it was also found that IDA plasma clearance was lower in patients whose creatinine clearance was less than 60 ml/min [group N, 122.8 +/- 44.0 l/h; group L, 104.4 +/- 27.7 l/h (P = 0.58) vs group R, 83.4 +/- 18.3 l/h (P = 0.037)]. The IDAol terminal half-life and mean residence time (MRT) were significantly increased in patients with impaired kidney function [MRT: group N, 63.6 +/- 10.8 h; group L, 69.9 +/- 10.2 h (P = 0.27) vs group R, 83.2 +/- 10.9 h (P = 0.025) and t1/2 gamma: group N, 41.3 +/- 10.1 h; group L, 47.0 +/- 7.4 h (P = 0.31) vs group R, 55.8 +/- 8.2 h (P = 0.025)]. After oral treatment, drug absorption occurred during in the first 2-4 h after IDA administration; a biphasic decay pattern was observed thereafter. The main metabolite observed in all patients was again IDAol. The AUC of IDAol was greater after oral administration than after i.v. treatment in proportion to the AUC of IDA (i.v.: AUC-IDAol/AUC-IDA, 2.4-18.9; p.o.: AUC-IDAol/AUC-IDA, 4.1-21.4). Following oral dosing, a substantial amount of 4-demethoxydaunomycinone (AG1) was found in 11/21 patients.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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There is much evidence to suggest that scleroderma in human patients is caused by a fundamental defect in the immune system. In tightskin mice, the scleroderma syndrome is associated with autoimmunity, particularly autoantibodies interacting with scleroderma target antigens.  相似文献   
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The renin-aldosterone axis in patients with diabetes insipidus   总被引:1,自引:1,他引:0  
OBJECTIVE The objective of the present study was to investigate the renin-aldosterone axis in neurogenic diabetes insipidus in man, in view of the fact that profound abnormalities of this axis have been described in experimental animals with congenital neurogenic diabetes insipidus. DESIGN AND PATIENTS Nine patients with neurogenic diabetes insipidus and 11 healthy subjects (controls) were examined under basal conditions, following the standard 8-hour water deprivation test and 1 hour after a subsequent oral rehydration. MEASUREMENTS Plasma and urine osmolalities were determined by freezing point depression, plasma sodium and potassium by a method using an ion-selective electrode, plasma AVP, Cortisol, aldosterone and plasma renin activity by radioimmunoassay. RESULTS Plasma renin activities under basal conditions were significantly higher in patients with diabetes insipidus than in controls (mean ± SEM 23.4 ± 6.6 vs 7.8 ± 1.2 ng/ I min). In the diabetes insipidus group, water deprivation caused a twofold Increase in plasma renin activities (48 ± 13.8 ng/l min), while in the control group plasma renin activity levels were not significantly altered (10.2 ± 1.2 ng/l min). Rehydration did not alter plasma renin activity levels in either group (patients 50.4 ± 13.2, controls 9.0 ± 2.4 ng/l min). Plasma aldosterone concentrations under basal conditions did not differ between the two groups (patients 302.4 ± 37, controls 326.4 ± 36.5 pmol/l) and did not change in patients with diabetes insipidus after water deprivation or rehydration (307.5 ± 67.2 and 385.5 ± 91 pmol/l, respectively). Conversely, controls showed a significant decrease in plasma aldosterone levels after dehydration (201 ± 27.9 pmol/l), which was attributed to the circardian variation in aldosterone secretion, as shown by a parallel decrease in plasma Cortisol levels. CONCLUSIONS Patients with diabetes insipidus are hyper-reninaemic, probably because of chronic volume contraction. There is a dissociation between renin and aldosterone in patients with diabetes insipidus under basal conditions, which is exaggerated during water deprivation.  相似文献   
9.
High intensity focused ultrasound: physical principles and devices.   总被引:7,自引:0,他引:7  
High intensity focused ultrasound (HIFU) is gaining rapid clinical acceptance as a treatment modality enabling non-invasive tissue heating and ablation for numerous applications. HIFU treatments are usually carried out in a single session, often as a day case procedure, with the patient either fully conscious, lightly sedated or under light general anaesthesia. A major advantage of HIFU over other thermal ablation techniques is that there is no necessity for the transcutaneous insertion of probes into the target tissue. The high powered focused beams employed are generated from sources placed either outside the body (for treatment of tumours of the liver, kidney, breast, uterus, pancreas and bone) or in the rectum (for treatment of the prostate), and are designed to enable rapid heating of a target tissue volume, while leaving tissue in the ultrasound propagation path relatively unaffected. Given the wide-ranging applicability of HIFU, numerous extra-corporeal, transrectal and interstitial devices have been designed to optimise application-specific treatment delivery. Their principle of operation is described here, alongside an overview of the physical mechanisms governing HIFU propagation and HIFU-induced heating. Present methods of characterising HIFU fields and of quantifying HIFU exposure and its associated effects are also addressed.  相似文献   
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Detailed analyses of the neuropathologic changes in the cerebralcortex of elderly individuals and Alzheimer's disease patientshave demonstrated that certain components of the neocorticaland hippocampal circuits are likely to be selectively vulnerable.Based on the distribution of neurofibrillary tangles (NFTs)and senile plaques, it has been proposed that a global cortico-corticaldisconnection leads to the loss of integrated functions observedin Alzheimer's disease. In order to investigate the distributionof lesions associated with aging as well as with the earliestsymptoms of senile dementia, we performed a quantitative neuropathologicavaluation of a large series of elderly patients representingthe entire autopsy population for the year 1989 from a geriatrichospital. Among the 145 cases quantitatively assessed, therewere 102 nondemented patients, 33 patients presenting clinicallywith globally intact intellectual function but early signs ofimpairment of specific cognitive functions, and 10 cases withsenile dementia of the Alzheimer type. All of the cases hadNFTs in layer II of the entorhinal cortex, regardless of theirclinical diagnosis, and most cases had some NFTs in the CA1field of the hippocampus. Severe pathologic changes within theinferior temporal neocortex were observed only in the dementedcases. The extent of amyloid deposition was not correlated withthe clinical diagnosis and seemed to be present in the neocorticalareas earlier than in the hippocampal formation. Also, severalcases contained NFTs without amyloid deposition, but amyloidnever occurred without NFTs. These results suggests that involvementof certain structures within the hippocampal formation is aconsistent feature of aging. Thus, involvement of the hippocampalformation may be a necessary, but not sufficient, conditionfor the clinical expression of dementia, which is likely tobe more closely related to the progressive degeneration of selectneuronal populations in the neocortex.  相似文献   
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