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Metyrapone was used in the long-term management of 13 patients with pituitary-dependent bilateral adrenal hyperplasia (Cushing''s disease). The total length of treatment ranged from two to 66 months, with a mean of 21 months. The clinical features of the disease rapidly improved on metyrapone and this improvement was maintained. Although plasma ACTH concentrations rose in all patients, the increase was insufficient to overcome the adrenal blockade induced by the drug. Eight of the 13 patients had additional external pituitary irradiation as definitive treatment of their disease and one underwent a transfrontal hypophysectomy. Radiotherapy cured one patient, and after three years metyrapone was withdrawn. Slight hirsuties was noted in four of the seven women who received the drug for six months or more. A fifth woman had more severe hirsuties and this led to bilateral adrenalectomy. Other than hirsuties, side effects were few and the routine use of metyrapone is recommended as an adjunct to more definitive treatment in all patients who present with Cushing''s syndrome, irrespective of aetiology.  相似文献   
3.
Twenty-three patients with adrenocorticotrophic hormone-(ACTH)-dependent Cushing''s syndrome were subjected to selective venous catheterisation and sampling for ACTH on a total of 26 occasions. Out of 10 patients with pituitary-dependent disease, nine had raised ACTH concentrations in one or both high internal jugular vein samples. Eight patients had 11 proved sites of ectopic hormone production: of these, six were correctly identified by the sampling technique, and in four of them this was the only accurate method of localisation. The results of one catheterisation were misleading, and on 10 occasions they were inconclusive; five patients remained undiagnosed by any method. Overall, 15 of the 26 catheterisations provided diagnostically valuable information. Selective venous catheterisation and sampling for ACTH is effective in confirming a pituitary source of the hormone and may be valuable in locating the source of ectopic ACTH production in some cases.  相似文献   
4.
Neural correlates of behavioral preference for culturally familiar drinks   总被引:1,自引:0,他引:1  
Coca-Cola (Coke) and Pepsi are nearly identical in chemical composition, yet humans routinely display strong subjective preferences for one or the other. This simple observation raises the important question of how cultural messages combine with content to shape our perceptions; even to the point of modifying behavioral preferences for a primary reward like a sugared drink. We delivered Coke and Pepsi to human subjects in behavioral taste tests and also in passive experiments carried out during functional magnetic resonance imaging (fMRI). Two conditions were examined: (1) anonymous delivery of Coke and Pepsi and (2) brand-cued delivery of Coke and Pepsi. For the anonymous task, we report a consistent neural response in the ventromedial prefrontal cortex that correlated with subjects' behavioral preferences for these beverages. In the brand-cued experiment, brand knowledge for one of the drinks had a dramatic influence on expressed behavioral preferences and on the measured brain responses.  相似文献   
5.
Ghosh R  Tomlin C 《Systems biology》2004,1(1):170-183
Hybrid automata are an eminently suitable modelling framework for biological protein regulatory networks, as the protein concentration dynamics inside each biological cell are modelled using linear differential equations; inputs activate or deactivate these continuous dynamics through discrete switches, which themselves are controlled by protein concentrations reaching given thresholds. This paper proposes an iterative refinement algorithm for computing discrete abstractions of a class of hybrid automata with piecewise affine continuous dynamics and forced discrete transitions, defined completely in terms of symbolic variables and parameters. Furthermore, these discrete abstractions are utilised to compute symbolic parametric backward reachable sets from the equilibria of the hybrid automata, that are guaranteed to be exact or conservative under-approximations. The algorithm is then implemented using MATLAB and QEPCAD, to compute reachable sets for the biologically observed equilibria of the multiple cell Delta-Notch protein signalling automaton with symbolic parameters. The results are analysed to show that novel, non-intuitive, and biologically interesting properties can be deduced from the reachability computation, thus demonstrating the utility of the algorithm.  相似文献   
6.
The Schizosaccharomyces pombe septation initiation network (SIN) triggers actomyosin ring constriction, septation, and cell division. It is organized at the spindle pole body (SPB) by the scaffold proteins Sid4p and Cdc11p. Here, we dissect the contributions of Sid4p and Cdc11p in anchoring SIN components and SIN regulators to the SPB. We find that Sid4p interacts with the SIN activator, Plo1p, in addition to Cdc11p and Dma1p. While the C terminus of Cdc11p is involved in binding Sid4p, its N-terminal half is involved in a wide variety of direct protein-protein interactions, including those with Spg1p, Sid2p, Cdc16p, and Cdk1p-Cdc13p. Given that the localizations of the remaining SIN components depend on Spg1p or Cdc16p, these data allow us to build a comprehensive model of SIN component organization at the SPB. FRAP experiments indicate that Sid4p and Cdc11p are stable SPB components, whereas signaling components of the SIN are dynamically associated with these structures. Our results suggest that the Sid4p-Cdc11p complex organizes a signaling hub on the SPB and that this hub coordinates cell and nuclear division.  相似文献   
7.
中国的炭疽杆菌DNA分型及其地理分布   总被引:7,自引:1,他引:6  
炭疽广泛分布于中国各地,特别是西部地区,并经常造成人畜疾病,在一项合作研究中,用多位点VNTR分析(MLVA)对从1952-1998年自中国主要地理流行区域分离的病人,病畜和土壤等来源的炭疽杆菌进行了基因分型,MLVA分析结果揭示了21种新的基因型,其等位基因组合在以前世界范围分离物的研究中未曾发现,此外,分离物的分群显示,A3b组是地理上最广泛分布的基因组,说明该组可能是中国的“地方流行株”。而来自古丝绸之路重要贸易中心新疆的大量分离株其基因型特别分散。  相似文献   
8.
MicroRNAs (miRNAs) are endogenous, non-coding, single-stranded RNAs about 21 nucleotides in length. miRNAs have been shown to regulate gene expression and thus influence a wide range of physiological and pathological processes. Moreover, they are detected in a variety of sources, including tissues, serum, and other body fluids, such as saliva. The role of miRNAs is evident in various malignant and nonmalignant diseases, and there is accumulating evidence also for an important role of miRNAs in systemic rheumatic diseases. Abnormal expression of miRNAs has been reported in autoimmune diseases, mainly in systemic lupus erythematosus and rheumatoid arthritis. miRNAs can be aberrantly expressed even in the different stages of disease progression, allowing miRNAs to be important biomarkers, to help understand the pathogenesis of the disease, and to monitor disease activity and effects of treatment. Different groups have demonstrated a link between miRNA expression and disease activity, as in the case of renal flares in lupus patients. Moreover, miRNAs are emerging as potential targets for new therapeutic strategies of autoimmune disorders. Taken together, recent data demonstrate that miRNAs can influence mechanisms involved in the pathogenesis, relapse, and specific organ involvement of autoimmune diseases. The ultimate goal is the identification of a miRNA target or targets that could be manipulated through specific therapies, aiming at activation or inhibition of specific miRNAs responsible for the development of disease.  相似文献   
9.

Introduction  

The presence of anti-topoisomerase I (topo I) antibodies is a classic scleroderma (SSc) marker presumably associated with a unique clinical subset. Here the clinical association of anti-topo I was reevaluated in unselected patients seen in a rheumatology clinic setting.  相似文献   
10.
The spindle-pole body (SPB), the yeast analog of the centrosome, serves as the major microtubule (MT) organizing center in the yeast cell. In addition to this central function, the SPB organizes and concentrates proteins required for proper coordination between the nuclear-division cycle and cytokinesis. For example, the Schizosaccharomyces pombe septation-initiation network (SIN), which is responsible for initiating actomyosin ring constriction and septation, is assembled at the SPB through its two scaffolding components, Sid4 and Cdc11. In an effort to identify novel SIN interactors, we purified Cdc11 and identified by mass spectrometry a previously uncharacterized protein associated with it, Ppc89. Ppc89 localizes constitutively to the SPB and interacts directly with Sid4. A fusion between the N-terminal 300 amino acids of Sid4 and a SPB targeting domain of Ppc89 supplies the essential function of Sid4 in anchoring the SIN. ppc89Delta cells are inviable and exhibit defects in SPB integrity, and hence in spindle formation, chromosome segregation, and SIN localization. Ppc89 overproduction is lethal, resulting primarily in a G2 arrest accompanied by massive enlargement of the SPB and increased SPB MT nucleation. These results suggest a fundamental role for Ppc89 in organization of the S. pombe SPB.  相似文献   
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