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Parker  VS; Malhotra  CM; Ho  G  Jr; Kaplan  SR 《Radiology》1984,153(2):343-347
The sternomanubrial joint (SMJ) was evaluated on the lateral chest radiograph in 177 patients with rheumatic disease and 69 non-rheumatic controls. Abnormalities were categorized as inflammatory changes, proliferative changes, or bone fusion. Patients with rheumatoid arthritis, psoriatic arthritis, or gout were found to have an increased incidence of inflammatory changes. Rheumatoid variants predisposed to early fusion of the SMJ. Patients with diffuse idiopathic skeletal hyperostosis (DISH) exhibited massive and unique hyperostotic changes.  相似文献   
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A long-lasting decrease of the basal and stress-induced arterial blood pressure was obtained in rats with inherited emotional stress-induced arterial hypertension by means of injections of the dopamine precursor L-DOPA during early development (21-25 days after birth). The restoring effect of L-DOPA was produced through enhancement of synthesis of the brain noradrenaline and, perhaps, adrenaline. The effect was associated with a normalization of the response of the brain adrenergic system to noradrenaline and, presumably, with increase of tyrosine hydroxylase activity in the cortex and hindbrain.  相似文献   
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Purpose: To develop a population pharmacokinetic–pharmacodynamic (PKPD) model for insulin in rats. Methods: Rats were administered insulin either subcutaneously (s.c) (0.26,1.3,2.6 U/kg) or by pulmonary route (spray-instillation (s.i)) (0.26,1.3,2.6,13,26 U/kg). Insulin (0.26,1.3,2.6 U/kg) combined with different combinations of hydroxy methyl amino propionic acid (HMAP: 5,10,16,25 mg/kg) was also administered by spray-instillation. Plasma insulin and glucose concentrations at pre-determined time points were measured. Population pharmacokinetic–pharmacodynamic modeling was performed using NONMEM. Results: Insulin exhibited dose-disproportional PK across formulations and routes of administration. The kinetic model suggested monoexponential disposition with simultaneous first order (64%-dimeric form of insulin) – zero order (36%-hexameric form of insulin) absorption. Maximum relative bioavailability (relative to s.c – 0.26 U/kg) of spray-instilled insulin was 46%. Addition of HMAP increased the relative bioavailability of insulin administered via spray-instilled route by 40%. The insulin–glucose relationship was characterized using an indirect response model, wherein, insulin stimulation of glucose uptake into muscle cells was assumed. The basal zero order production rate of glucose (kG, prod) was estimated as 0.98 mg/dl/min. The SC50 was fixed at 80 μ U/ml based on literature reports and the Smax was estimated to be 6. Conclusions: The proposed PKPD model satisfactorily describes insulin disposition and glucose concentrations across range of doses with and without HMAP.  相似文献   
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Background

Multidetector CT (MDCT) represents breakthrough in CT technology, significantly improving CT Angiography applications.

Methods

Twenty one patients with aortoiliac & branch aneurysms or stenosis were evaluated by Digital Subtraction Angiography (DSA) and Multidetector CT (MDCT) before and after endovascular repair.

Results

There were eight cases of aortic & branch aneurysms and 13 with stenosis. Four cases had aortic aneurysms, while one case had left subclavian artery aneurysm, thoracic aneurysm, femoral and popliteal artery pseudoaneurysms. Of the 13 cases with stenotic lesions, iliac stenosis was seen in eight patients. The others included carotid, vertebral, aortic, renal and aortic bifurcation stenotic. MDCT offered accurate information on shape and size of aneurysm, shape and patency of graft, the presence or absence of perigraft thrombosis or endoleaks, while in stenotic lesions it provided useful information on shape of graft, its location, its patency and the presence and quantity of distal flow.

Conclusion

MDCT was found to be a potentially useful modality during initial evaluation and follow up of patient undergoing endovascular repair.Key Words: Multidetector Computed Tomography, Endovascular stents, Arterial disease  相似文献   
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Hemicastration of male rats produced rapid changes in plasma testosterone (T) levels both in summer and in winter. However, in winter, after unilateral castration, the duration of T maximum decrease was found to be longer, but the compensatory increase of blood T following its drop was more dramatic as compared to the summer season. The intraperitoneal (i.p.) 5-hydroxytryptophan (5-HTP) administration blocked the compensatory increase in plasma T that followed its drop induced by hemicastration. At the same time, under similar experimental conditions, a preliminary injection of p-chlorophenyl-alanine (PCPA) was accompanied by a more marked rise of plasma T than in control unilaterally castrated rats. After the injection of serotonin (5-HT) into the lateral ventricle of the brain there was no effect on the blood T content in rats with intact gonads. However, 5-HT injection to hemicastrated animals under similar conditions completely prevented the compensatory increase of T level in blood after its fall caused by the operation. On the other hand, double intraventricular injection of methysergide was followed by a more marked rise of blood T content as compared with the control hemicastrated rats. The conclusion is drawn that brain serotoninergic neurons are involved in feedback mechanisms related to the control of hypothalamic-pituitary-testicular complex.  相似文献   
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