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31.
Forty depressed patients and 36 age- and sex-matched controls were given 250 μg ACTH1–24 by bolus. Plasma steroid hormone levels were measured prior to and 60 min after ACTH administration. The depressed patients had significantly greater cortisol (F), 11-deoxycortisol (S), androstenedione (AD), and 17-hydroxyprogesterone (17-OHP) responses (delta; p<0.05) and a marginally greater 11β-hydroxyandrostenedione (11β-OHAD) response (delta; p=0.091) than the controls. There was no significant difference in the corticosterone (B) response between the two groups.

With the exception of 11β-OHAD, all the steroid hormones were significantly negatively correlated with age in the controls, but only S and AD marginally demonstrated this relationship in the depressed patients. F, S, AD, 17-OHP, and B, but not 11β-OHAD, were significantly positively correlated with each other in the controls, but only F was significantly correlated with AD in the depressed patients. These data suggest that the hypercortisolemia found in some depressed patients involves increased precursor and metabolite levels both at baseline and in response to exogenous ACTH, compared to controls. Furthermore, variability in these precursors is greater in depressed patients, and their relationship to age is lost. These findings are consistent with the hypothesis that adrenal products other than cortisol also could be related to affective symptoms.  相似文献   

32.
Twenty patients with advanced malignant disease submitted to autologous bone marrow transplantation with marrow either unpurged (10 patients) or purged in vitro with mafosfamide (10 patients) after ablative chemotherapy, received simultaneously autologous peripheral blood stem cells (PBSC) collected during one to three 3 h cytapheresis procedures. The kinetics of the hematological recovery of these patients were compared to those of a group of patients suffering from similar diseases and grafted in the same institution with either unpurged marrow only (14 patients) or purged in vitro with mafosfamide (six patients). The median times to reach 10(9)/l leukocytes, 0.5 x 10(9)/l polymorphs, and 50 x 10(9)/l platelets were reduced by 10, 10, and 13 days, respectively, in patients transfused with both autologous bone marrow and peripheral blood stem cells as compared to those receiving bone marrow only. A reduction in the numbers of days spent in hospital post-transplantation (p less than 0.01), of days of fever greater than 38 degrees C (p = NS), and of platelet (p = 0.07) and of red blood cell transfusions (p less than 0.01) were also observed in the group of patients grafted with bone marrow and PBSC.  相似文献   
33.
Percutaneous transvenous mitral commissurotomy was performed successfully via the transjugular approach in a patient with severe rheumatic mitral stenosis and obstruction of the inferior vena cava due to prior liver transplantation. This case demonstrates the advantage of the jugular approach in patients with difficult anatomy.  相似文献   
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The percutaneous anterior approach to the celiac plexus using CT guidance   总被引:3,自引:0,他引:3  
This paper describes a new approach to the neurolytic block of the celiac plexus through the anterior abdominal wall using CT guidance. In 5 patients, CT guidance was used for needle placement and visualization of the spread of the injection. Once the pain has been relieved on completion of the neurolytic block, the radiologist proceeds with the biopsy. Pain relief was obtained in 80% of the cases after 2 weeks and in 60% after 6 months. No serious complications were observed. The anterior approach is simple and is useful in those patients with upper chronic abdominal pain scheduled for biopsy of the pancreas, and in those terminally ill patients who cannot tolerate the prone position.  相似文献   
36.
A microprocessor-based real-time digital vibrotactile vocoder system has been developed to train the deaf and for artificial hearing research. The system is composed of a microcomputer module with a digital signal processor interface units and an attenuator/driver circuit. Live or digitised (stored or synthetic) speech is presented to the skin spectrally through a belt housing eight or 16 vibrators. Speech is processed in real time using a fast Fourier transform. The system is also capable of presenting any arbitrary spatiotemporal pattern on the skin for artificial hearing experiments. A preliminary experiment with a deaf subject indicates that the system is potentially an effective device for artificial hearing.  相似文献   
37.
VC is an important clinical entity; however, very little information is available on its resolution. Induction and regression of calcitriol-induced VC was studied in 47 rats. After calcitriol withdrawal, there was a relatively rapid regression of VC mediated by an active cellular process. INTRODUCTION: Vascular calcifications (VCs) represent an important risk factor for cardiovascular death. Although VCs are prevalent in relevant diseases (e.g., chronic kidney disease, osteoporosis, diabetes), the reversibility of extraskeletal calcifications is an unresolved issue. This study was conducted to investigate (1) the in vivo effect of calcitriol on VC and (2) whether calcitriol-induced VC would regress after suppression of calcitriol treatment. MATERIALS AND METHODS: The calcifying effect of calcitriol was studied in four groups of rats (n = 8) that received calcitriol (1 mug/kg, IP) for 2, 4, 6, and 8 days. The reversibility of VC was studied in three additional groups (n = 5) treated with 1 mug/kg of calcitriol for 8 days that were subsequently killed 1, 2, and 9 weeks after the last calcitriol dose. Aortic VC was assessed by histology and by quantification of aortic calcium and phosphorus content. The aortic wall was studied by histology and immunohistochemistry. Statistical analysis was performed by ANOVA and t-tests. RESULTS: Calcitriol administration resulted in a time-dependent induction of VC, with aortic calcium and phosphorus being significantly increased at 6 and 8 days. Treatment with calcitriol for 8 days resulted in massive medial calcification of the aorta with a 10- to 30-fold increase in the aortic Ca and P content. After suppressing calcitriol administration, a progressive decrease in von Kossa staining and aortic Ca (from 32.8 +/- 2.5 to 9.3 +/- 1.8 mg/g of tissue, p < 0.001) and P (from 11.9 +/- 1.2 to 2.7 +/- 1.8 mg/g of tissue, p = 0.001) content was evidenced. Histology of the aortic wall showed monocytes adhered to the aortic endothelium and macrophages involved in the reabsorption of calcium deposits. CONCLUSIONS: Our results show that calcitriol treatment induces time-dependent VC. After calcitriol withdrawal, VC regress rapidly with aortic calcium and phosphorus decreasing by 75% in the course of 9 weeks. An active cellular process seems to be involved in regression of VC.  相似文献   
38.
Spinocerebellar ataxia-1 (SCA1) is caused by the expansion of a polyglutamine repeat within the disease protein, ataxin-1. The overexpression of mutant ataxin-1 in SCA1 transgenic mice results in the formation of cytoplasmic vacuoles in Purkinje neurons (PKN) of the cerebellum. PKN are closely associated with neighboring Bergmann glia. To elucidate the role of Bergmann glia in SCA1 pathogenesis, cerebellar tissue from 7 days to 6 wks old SCA1 transgenic and wildtype mice were used. We observed that Bergmann glial S100B protein is localized to the cytoplasmic vacuoles in SCA1 PKN. These S100B positive cytoplasmic vacuoles began appearing much before the onset of behavioral abnormalities, and were negative for other glial and PKN marker proteins. Electron micrographs revealed that vacuoles have a double membrane. In the vacuoles, S100B colocalized with receptors of advanced glycation end-products (RAGE), and S100B co-immunoprecipated with cerebellar RAGE. In SCA1 PKN cultures, exogenous S100B protein interacted with the PKN membranes and was internalized. These data suggest that glial S100B though extrinsic to PKN is sequestered into cytoplasmic vacuoles in SCA1 mice at early postnatal ages. Further, S100B may be binding to RAGE on Purkinje cell membranes before these membranes are internalized.  相似文献   
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40.
BACKGROUND: We are interested in identifying susceptibility genes that predispose subjects to attempted suicide. METHODS: We conducted a secondary analysis of genome-wide linkage data from 162 bipolar pedigrees that incorporated attempted suicide as a clinical covariate. RESULTS: The strongest covariate-based linkage signal was seen on 2p12 at marker D2S1777. The logarithm of odds (LOD) score at marker D2S1777 rose from 1.56 to 3.82 after inclusion of the suicide covariate, resulting in significant chromosome-wide empirically derived p-values for the overall linkage finding (p = .01) and for the change in LOD score after the inclusion of the covariate (p = .02). CONCLUSIONS: The finding on chromosome 2 replicates results from two previous studies of attempted suicide in pedigrees with alcohol dependence and in pedigrees with recurrent early-onset depression. Combined, these three studies provide compelling evidence for a locus influencing attempted suicide on 2p12.  相似文献   
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