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41.
Ontogen Corporation and Daylight Chemical Information Systems have recently integrated a molecule data type in an object-relational database management system. The authors explain how this innovation unites chemical and biological data management into a single universal database. All chemical information storage, searching and retrieval is performed using a standard structured query language. The authors describe using rapid application development methods for quickly building an application to access the database and they demonstrate that these techniques can simplify and standardize the management of pharmaceutical data.  相似文献   
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This article reports the first case of immune hemolytic anemia possibly associated with the ingestion of suprofen. The patient suffered from massive hemoglobinuria and acute renal failure. Serologic studies of the patient's serum revealed suprofen-dependent red cell antibodies. However, tolmetin-dependent antibodies were also found in the serum, showing the same properties as the suprofen antibodies and an even higher titer. The patient not only had drug-dependent antibodies in the serum, but also had developed autoantibodies, a phenomenon that has been described for several other drugs. The working mechanism by which suprofen and tolmetin caused immune hemolysis had properties of both the immune complex model and the induction of autoimmunity. Although it was unclear whether the immune hemolytic anemia was the result of suprofen, tolmetin, or cross-reacting antibodies, we feel that suprofen should be added to the list of nonsteroidal anti-inflammatory drugs associated with a positive direct antiglobulin test.  相似文献   
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Acute neurohormonal responses to hypoxaemia in man   总被引:1,自引:0,他引:1  
We have studied the integrated neuroendocrine and haemodynamic effects of acute hypoxaemia in ten healthy volunteers studied on two separate occasions. After reaching a resting haemodynamic state, subjects breathed either room air or a nitrogen/oxygen mixture which rendered arterial oxygen saturation between 75% and 80%. Measurements of pulmonary and systemic haemodynamics were made and blood samples taken at baseline and after 30 min breathing air or the hypoxic gas. Blood was assayed for plasma sodium and potassium, renin-angiotensin-aldosterone system activity, natriuretic peptides, cortisol and catecholamines. Hypoxaemia significantly increased heart rate, cardiac output and mean pulmonary artery pressure (P pa), but not mean arterial pressure compared with normoxaemia. Although plasma renin activity, angiotensin II and cortisol were unaffected by hypoxaemia, plasma aldosterone fell significantly in comparison with normoxaemia. This was associated with an increase in plasma atrial natriuretic peptide (ANP) but not b-type natriuretic peptide (BNP) during hypoxaemia whilst no changes were observed during normoxaemia. The increase in plasma ANP correlated positively with the increase inP pa. During hypoxaemia there is therefore dissociation of the renin-angiotensin-aldosterone system where plasma aldosterone decreased, despite there being no effects on plasma renin activity and angiotensin II or on plasma cortisol. This dissociation may be due to increased levels of ANP but not BNP having specific inhibitory effects on aldosterone biosynthesis. ANP increased in proportion to the degree of pulmonary vasoconstriction induced by hypoxaemia which may indicate a counter-regulatory role.  相似文献   
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Conces  DJ  Jr; Vix  VA; Klatte  EC 《Radiology》1985,156(2):445-447
Two cases of left atrial myxoma were evaluated with magnetic resonance (MR) imaging. In both cases, the myxoma was clearly defined as to its location, origin, and size. In one case, the myxoma prolapsed through the mitral valve. Our study indicates that MR imaging is valuable in the diagnosis of myxomas.  相似文献   
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D J Clark  A Grove  R I Cargill    B J Lipworth 《Thorax》1996,51(3):262-266
BACKGROUND: A study was performed to compare the adrenal suppression caused by inhaled fluticasone propionate and budesonide on a microgram equivalent basis, each given by metered dose inhaler to asthmatic patients. METHODS: Twelve asthmatic patients of mean age 29.9 years, with a forced expiratory volume in one second (FEV1) 92.9% predicted and forced expiratory flow 25-75% (FEF25-75) 69.5% predicted, on less than or equal to 400 micrograms/day inhaled corticosteroid, were studied in a double blind placebo controlled crossover design comparing single doses of inhaled budesonide 400, 1000, 1600, 2000 micrograms and fluticasone propionate 500, 1000, 1500, 2000 micrograms. Doses were administered at 22.00 hours by metered dose inhaler with mouth rinsing and measurements were made in the laboratory 10 hours later. RESULTS: Serum cortisol levels compared with placebo (mean 325.2 nmol/l) were suppressed by fluticasone at doses of 1500 micrograms (211.6 nmol/l) and 2000 micrograms (112.3 nmol/l) and by budesonide at 2000 micrograms (243.4 nmol/l). Fluticasone propionate 2000 micrograms produced lower absolute serum cortisol levels than budesonide 2000 micrograms (95% CI for difference 42.9 to 219.2). The dose ratio (geometric mean) for the relative potency was 2.89 fold (95% CI 1.19 to 7.07). In terms of percentage suppression versus placebo, fluticasone propionate also produced greater effects (means and 95% CI for difference): budesonide 1600 micrograms (16.0) versus fluticasone propionate 1500 micrograms (40.9) (95% CI -0.6 to 50.6), budesonide 2000 micrograms (26.0) versus fluticasone 2000 micrograms (65.2) (95% CI 10.5 to 67.8). Individual serum cortisol levels at the two highest doses showed 15 of 24 patients below the normal limit of the reference range (150 nmol/l) for fluticasone and five of 24 for budesonide. Fluticasone propionate also caused greater ACTH suppression than budesonide (as % versus placebo): budesonide 1600 micrograms (12.0) versus fluticasone propionate 1500 micrograms (31.9) (95% CI 7.6 to 32.1), budesonide 2000 micrograms (13.5) versus fluticasone propionate 2000 micrograms (44.4) (95% CI 13.2 to 48.7). For overnight 10 hour urinary cortisol (nmol/10 hours) there was a difference between the lowest doses of the two drugs: budesonide 400 micrograms (37.2) versus fluticasone propionate 500 micrograms (19.9) (95% CI 6.9 to 27.8). CONCLUSIONS: Like budesonide the systemic bioactivity of fluticasone propionate is mainly due to lung vascular absorption. Fluticasone propionate exhibited at least twofold greater adrenal suppression than budesonide on a microgram equivalent basis in asthmatic patients.  相似文献   
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