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31.
A 26-year-old man who presented with a 2-year history of intermittent gynecomastia with recent onset of fever, night sweats, and abdominal distension was found to have a left-sided adrenocortical carcinoma with metastases to the liver and spine. Sudden death occurred 1 month after his presentation. At autopsy a saddle pulmonary thromboembolus was found occluding the pulmonary outflow tract, with smaller more peripheral pulmonary thromboemboli. No tumor deposits were identified in the thromboemboli. The thromboemboli had arisen from a tongue of tumor that had grown through the left adrenal vein into the inferior vena cava. Despite a high rate of angio-invasion there are very few reports of sudden death resulting from this phenomenon in patients with adrenocortical carcinoma.  相似文献   
32.
The surgical risk of colectomy in patients with cirrhosis   总被引:5,自引:1,他引:4  
The records of 54 patients with documented cirrhosis who underwent colectomy between January 1970 and January 1984 were studied to assess the operative risk and to determine the preoperative predictive risk factors. In-hospital mortality was 24 percent (13 patients), and postoperative complications occurred in 48 percent (26 patients). The risk of surgical intervention was significantly increased if encephalopathy, ascites, anemia, or hypoalbuminemia was present before operation. A simple operative risk index involving the presence of encephalopathy and ascites and the levels of hemoglobin and albumin is proposed to help distinguish a low-risk subgroup in whom postoperative mortality was 12.8 percent from a high-risk subgroup in whom postoperative mortality was 53.3 percent.  相似文献   
33.
34.
The relations between three hormones of the hypothalamic-pituitary-adrenocortical (HPA) axis, beta-endorphin (β-EP), corticotropin-releasing hormone (CRH) and cortisol, and mood change were examined in 11 elite runners and 12 highly trained meditators matched in age, sex, and personality. Despite metabolic differences between running and meditation, we predicted that mood change after these activities would be similar when associated with similar hormonal change. Compared to pre-test and control values, mood was elevated after both activities but not significantly different between the two groups at post-test. There were significant elevations of β-EP and CRH after running and of CRH after meditation, but no significant differences in CRH increases between groups. CRH was correlated with positive mood changes after running and meditation. Cortisol levels were generally high but erratic in both groups. We conclude that positive affect is associated with plasma CRH immunoreactivity which itself is significantly associated with circulating β-EP supporting a role for CRH in the release of β-EP. Increased CRH immunoreactivity following meditation indicates, however, that physical exercise is not an essential requirement for CRH release.  相似文献   
35.
Previous studies of human thyroid cells in culture (mostly from pathological tissues) failed to demonstrate a mitogenic effect of TSH, leading to the proposal that the growth effect of TSH in vivo might be indirect. To reexamine the influence of TSH on DNA synthesis and cell proliferation, we established primary cultures of normal thyroid tissue from nine subjects. When seeded in a 1% serum-supplemented medium, thyroid follicles released by collagenase/dispase digestion developed as a cell monolayer that responded to TSH by rounding up and by cytoplasmic retraction. When seeded in serum-free medium, the cells remained associated in dense aggregates surrounded by few slowly spreading cells. In the latter condition, the cells responded to TSH and other stimulators of cAMP production, such as cholera toxin and forskolin, by displaying very high iodide-trapping levels. Exposure to serum irreversibly abolished this differentiated function. TSH stimulated the proliferation (as shown by DNA content per culture dish) of 1% serum cultured cells (doubling times were reduced from 106 to 76 h) and increased by 100% the [3H]thymidine labeling indices. In serum-free cultured cells (dense aggregates or cell monolayers after initial seeding with serum), control levels of DNA synthesis were lower, and up to 8-fold stimulation of DNA synthesis occurred in response to 100 mU/L TSH (stimulation was consistently detected with 20 mU/L), based on measurements of [3H]thymidine incorporation into acid-precipitable material and counts of labeled nuclei on autoradiographs (up to 40% labeled nuclei within 24 h). The mitogenic effect of TSH required a high insulin concentration (8.3 X 10(-7) mol/L) or a low insulin-like growth factor I concentration. The mitogenic effects of TSH were mimicked in part by cholera toxin, forskolin, and dibutyryl cAMP. Epidermal growth factor and phorbol myristate ester also stimulated thyroid cell proliferation and DNA synthesis, but they potently inhibited TSH-stimulated iodide transport. We conclude that TSH, acting at least in part through cAMP, is a potent growth factor for human thyroid cells and thus provide an experimental basis in vitro for the well established in vivo goitrogenic action of TSH.  相似文献   
36.
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible.  相似文献   
37.
International Journal of Public Health - Die Übertragungswege des HIV, welche in der Bevölkerung eine Rolle spielen, sind heute bekannt. Neben der sexuellen Übertragung, der...  相似文献   
38.
Loading of tissue macrophages with dialysis-tubing-derived particles may occur during chronic haemodialysis. Previous studies have demonstrated that these particle-laden macrophages release significant quantities of prostaglandins. In these experiments, the effects of dialysis-tubing-particle loading on the release of the central inflammatory mediator, interleukin 1 (IL 1), was examined. Rats received daily injections of silicone or polyvinylchloride (PVC) particles, and were compared to animals given saline alone. The silicone and PVC groups received a total of 3 x 10(9) particles over a 4-week period. Non-stimulated peritoneal macrophages from control animals released a median of 4.1 (range 1.2-10.3) U IL 1 per 10(6) cells. In contrast, macrophages from silicone- and PVC-loaded animals spontaneously released high levels of IL 1 (median 21.8; range 10-36.7) and 94 (range 36-336) U per 10(6) cells respectively). Following in vitro stimulation with bacterial lipopolysaccharide (LPS), peritoneal macrophages from silicone- and PVC-treated animals released large amounts of IL 1 (median 538 (range 359-2017) U and median 653 (range 326-1134) U per 10(6) cells, respectively) as compared to LPS-stimulated macrophages from control animals (median 332 (range 130-306) U per 10(6) cells]. Zymosan or LPS stimulation of splenic cells from silicone- and PVC-loaded animals also secreted increased quantities of IL 1 as compared to controls. The chronic loading of tissue macrophages in dialysis patients with tubing-derived particles may result in augmented release of IL 1, with subsequent activation of inflammatory processes.  相似文献   
39.
The new complaints procedures which local authority social services departments have been required to introduce represent an important mechanism for managing the change of culture associated with recent community care reforms. They also represent a new genre in mechanisms of redress for welfare recipients. This paper reports the findings of a study which has observed considerable diversity in the ways in which local authorities are interpreting the nature and purposes of the new procedures and, in particular, the functions of review panels established under those procedures. Variations in the composition of panels, in the style of review panel proceedings, in perceptions of the panels' powers, and in the ways that complaints and complainants are constituted are all discussed. Attention is drawn to four competing interpretations of the review panels' role and to the need for these to be clarified and prioritised.  相似文献   
40.
1. Eight conscious rabbits were repeatedly subjected to progressive reduction in central blood volume by gradually inflating a thoracic inferior vena caval-cuff so cardiac index (CI) fell at a constant 8.5% of baseline/min. 2. Caval-cuff inflations were performed after 10 min exposure to 100, 21, 12–14 and 8–10% O2, with and without the addition of 3–4% CO2, in randomized order. 3. The haemodynamic response to progressive reduction in central blood volume was biphasic. In Phase I, systemic vascular conductance index (SVCI) fell linearly, supporting mean arterial pressure (MAP). When CI had fallen to a critical level, Phase II occurred in which SVCI rose abruptly, MAP plummeted and respiratory drive progressively increased. 4. During Phase I, there were independent linear relationships between Pao2 (but not Pao2) and the rates at which SVCI and MAP changed during the progressive fall of CI. The higher the level of Pao2, the greater was the rate of fall of SVCI and the less the rate of fall of MAP. 5. There was an inverted U-shaped effect of Pao2, on the level of CI at which Phase II occurred: (a) during hyperoxia (100% O2), Phase II occurred later than during normoxia (21% O2); and (b) across the normoxic and hypoxic gas mixtures (21–8% O2, with and without added CO2), there was an independent linear relationship between Pao2 (but not Pao2 or Pao2×Pao2) and the level of CI at which Phase II occurred. That is, the lower the level of Pao2, the later was the onset of Phase II. This interaction is best explained by an increased level of central sympathetic vasoconstrictor drive during hypoxia.  相似文献   
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