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51.
Six cases of methyldopa hepatitis, including two in which the patients died are reported; and 77 cases from the literature are reviewed. Patients in whom severe hepatotoxic reactions to methyldopa develop usually complain of prodromal symptoms typical of hepatitis, often with fever, one to four weeks after therapy is initiated. Jaundice, when it occurs, is usually manifest within three months.

Asymptomatic, transient elevations of serum transaminase levels may occur in patients receiving methyldopa. However, since the clinical and histologic features of hepatic injury from methyldopa are indistinguishable from viral hepatitis, it is suggested that the incidence of this iatrogenic disease is higher than generally appreciated.

Serum transaminase levels should be determined at the initiation of therapy with methyldopa and four weeks later. Moreover, any patient who has unexplained fever or the prodromal symptoms of hepatitis should undergo liver chemistry studies immediately.  相似文献   

52.
A new system is proposed for treating the spectrum of patients with high blood pressure. It is based on studies of the renin axis using renin profiling, pharmacologic probes and our bipolar vasoconstriction-volume hypothesis. The new system does not require renin profiling, pharmacologic testing or a vasoconstriction-volume analysis for widespread application. But these procedures, whenever available, will make treatment more efficient and more certain, and at the same time provide better base line definition. In the new system, all patients, except the elderly and those with congestive heart failure, bradycardia or a history of asthma, are treated first with propranolol alone, a procedure which will diminish or normalize blood pressure in many patients with high and noraml renin levels. For nonresponders, diuretic therapy is then superimposed. Subsequently, a propranolol subtraction trial picks out the low-renin patients who will usually respond to a diuretic alone. This program is likely to be fully effective in possible up to 85 per cent of patients. For the residual smaller fraction, drugs such as hydralazine, methyl DOPA, clonidine, reserpine or guanethidine are then added in traditional trial and error fashion. The proposed system has the theoretic attraction for long-term commitment, implicit in antihypertensive therapy, of achieving blood pressure control in large fractions with one drug instead of two or with two drugs instead of three or more. Moreover, the large groups who respond to therapy with propranolol alone (most high-renin and normal-renin patients) or to diuretics alone (most low-renin patients) gain the advantage of simple, more specific, long-term (i.e., antirenin or antivolume) therapy. The use of propranolol alone has practical and theoretic advantages over diuretics. Control may be achieved with even fewer side effects and without hypokalemia and chronic dehydration with its possibly adverse consequences (hyperuricemia, azotemia, hyperlipidemia, hyperreninemia, increased blood viscosity). Also, propranolol provides more direct control of the increased peripheral resistance and of neurogenically-induced swings in blood pressure. At the same time, the new system efficiently exploits the long-term use of diuretic therapy alone in low-renin patients in whom volume excess seems a causal factor. And it tends to avoid the use of diuretics in high-renin patients and of beta-blockers in low-renin patients in whom these drug types may be contraindicated.  相似文献   
53.
Frank P loop vectorcardiograms were recorded in 30 normal subjects and in 40 patients who had intraatrial conduction disturbances alone or in association with cardiac disease. High magnification of the P loop (0.1 mv = 3 cm) permitted accurate measurement of the P loop duration, magnitude and direction. High-frequency recordings allowed optimal evaluation of the notches, bites and conduction delays in the PsÊ loop.Four vectorcardiographic patterns have been selected as counterparts of the four types of enlarged P waves seen in electrocardiograms of patients with atrial conduction disturbances. When intraatrial conduction disturbances coexisted with left atrial enlargement, the PsÊ loop was larger and smoother. The role of partial or complete block in the specific internodal or interatrial pathways is discussed. High magnification, high-frequency vectorcardiography of the P loop seems to be the best available method for determining a specific pattern of intraatrial conduction disturbance.  相似文献   
54.
In a 65 year old man with hemoptysis, chest pain, weight loss, clubbing of the digits and a large mediastinal mass, the superior vena cava syndrome developed. He was treated for malignancy with radiation therapy and corticosteroids, but he died shortly after his admission to the hospital. Autopsy revealed syphilitic aortitis with an aneurysm of the ascending aorta compressing the superior vena cava and right mainstem bronchus. The postmortem serology corroborated the morphologic findings of tertiary syphilis. In this report we emphasize the important, although now uncommon, association between the superior vena cava syndrome and aneurysm of the aorta.  相似文献   
55.
The theoretical effect of variable ventricular function on left ventricular ejection time in aortic stenosis was predicted by applying data measured in 52 patients with pure aortic stenosis to equations derived from the relations of Gorlin and Gorlin and Weissler et al. Ejection time and aortic valve area are not, of necessity, linearly related because (Formula: see text) where LVET is left ventricular ejection time, k is a constant, SV is stroke volume, PG is mean aortic pressure gradient and AVA is aortic valve area. When the patients were separated into performance groups on the basis of cardiac index (at 2.8 liters/min per m2), the linear regression relating the measured SV/square root PG with valve area in 18 patients with normal function (SV/square root PG = 11.1 AVA + 2.0, r = 0.969, p less than 0.001) predicted ejection time prolongation with decreasing valve area. In 34 patients with poor function, however, the decrease in SV/square root PG with decreasing valve area was more marked (SV/square root PG = 12.6 AVA + 0.4, r = 0.894, p less than 0.001), predicting a shorter ejection time at any given valve area in this group. As predicted by the effect of valve area on the equation, ejection time becomes most variable at a small aortic valve area. Independent ejection time measurement in these patients validated the predicted effect.  相似文献   
56.
The role of the renin system in the maintenance of the elevated systolic blood pressure in isolated systolic hypertension was investigated in 31 patients who received long-term treatment with propranolol (120 mg daily) and in another group of 22 patients with isolated systolic hypertension who received a test dose of captopril (25 or 50 mg). The greatest systolic blood pressure decrease (35 +/- 5 mm Hg) by propranolol occurred in the high-renin group (n = 9), and the smallest decrease (3 +/- 2 mm Hg) in the low-renin group (n = 9), whereas in the normal-renin group (n = 13), systolic blood pressure was decreased by propranolol by 22 +/- 5 mm Hg. For all the propranolol-treated patients, the decrement in the systolic blood pressure by propranolol was related to the control plasma renin activity (r = 0.63, p less than 0.01) and to the concurrent change in plasma renin activity (r = 0.70, p less than 0.001). Captopril decreased the systolic blood pressure by 55 +/- 10 mm Hg in the high-renin group (n = 11) and by 17 +/- 5 mm Hg in the normal-renin group (n = 6), whereas the smallest decrease (12 +/- 5 mm Hg) in systolic blood pressure occurred in the low-renin group (n = 5). In all the captopril-tested patients (n = 22), the decrease in systolic blood pressure by captopril was related to the control plasma renin activity (r = 0.75, p less than 0.001). These results indicate that the plasma renin activity value indicates the participation of the renin-angiotensin system in the maintenance of the elevated systolic blood pressure in patients with isolated systolic hypertension.  相似文献   
57.
The practices of head and neck surgical oncologists must evolve to meet the unprecedented needs placed on our health care system by the Coronavirus disease 2019 (COVID‐19) pandemic. Guidelines are emerging to help guide the provision of head and neck cancer care, though in practice, it can be challenging to operationalize such recommendations. Head and neck surgeons at Wuhan University faced significant challenges in providing care for their patients. Similar challenges were faced by the University of Toronto during the severe acute respiratory syndrome (SARS) pandemic in 2003. Herein, we outline our combined experience and key practical considerations for maintaining an oncology service in the midst of a pandemic.  相似文献   
58.
CD31 is a standard immunostain for evaluating vascular lesions of the skin, but CD31 reactivity for histiocytes is reported in only a small variety of pathological conditions. CD68 and CD163 are well recognized stains for cutaneous histiocytic lesions. We compared immunostaining of CD31 within that of CD68 and CD163 in five cases each of cutaneous lesions containing histiocytes: healing biopsy site, granuloma annulare, xanthogranuloma, ruptured follicular cyst and sarcoidosis. Reactivity was graded on a scale of 0–3 for brightness of immunostaining. Immunoreactivity was seen in histiocytes in all specimens for CD31, CD68 and CD163. The average intensity of staining was 1.7–2.5 for CD31, 2.6–3 for CD68 and 2.9–3 for CD163. The staining was somewhat less for CD31 because the reactivity is localized on the cell surfaces, whereas CD68 and CD163 react with cell surfaces and cytoplasm. We conclude that histiocytes in cutaneous lesions stain for CD31 and the staining is comparable to, but less intense, than that seen with CD68 and CD163. Caution is suggested in interpretation of CD31 staining in skin specimens, as CD31 shows reactivity with histiocytes as well as endothelial cells.  相似文献   
59.
60.
Since the outbreak of COVID‐19 pandemic, clinicians have had to use personal protective equipment (PPE) for prolonged periods. This has been associated with detrimental effects, especially in relation to the skin health. The present study describes a comprehensive survey of healthcare workers (HCWs) to describe their experiences using PPE in managing COVID‐19 patients, with a particular focus on adverse skin reactions. A 24‐hour prevalence study and multi‐centre prospective survey were designed to capture the impact of PPE on skin health of hospital staff. Questionnaires incorporated demographics of participants, PPE type, usage time, and removal frequency. Participants reported the nature and location of any corresponding adverse skin reactions. The prevalence study included all staff in intensive care from a single centre, while the prospective study used a convenience sample of staff from three acute care providers in the United Kingdom. A total of 108 staff were recruited into the prevalence study, while 307 HCWs from a variety of professional backgrounds and demographics participated in the prospective study. Various skin adverse reactions were reported for the prevalence study, with the bridge of the nose (69%) and ears (30%) being the most affected. Of the six adverse skin reactions recorded for the prospective study, the most common were redness blanching (33%), itchiness (22%), and pressure damage (12%). These occurred predominantly at the bridge of the nose and the ears. There were significant associations (P < .05) between the adverse skin reactions with both the average daily time of PPE usage and the frequency of PPE relief. The comprehensive study revealed that the use of PPE leads to an array of skin reactions at various facial locations of HCWs. Improvements in guidelines are required for PPE usage to protect skin health. In addition, modifications to PPE designs are required to accommodate a range of face shapes and appropriate materials to improve device safety.  相似文献   
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