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11.
Preduodenal mechanisms in initiating gallbladder emptying in man   总被引:2,自引:0,他引:2  
The existence of preduodenal phases of gallbladder emptying in normal volunteers was investigated by evaluating the effect of sham feeding a sandwich (chew and spit) (n = 15), the sight and smell of food followed by sham feeding a cooked meal (n = 15), and gastric distension (intragastric balloon tube) (n = 9) on gallbladder emptying and comparing these responses with those after ingestion of a standard meal (n = 14). A control group given no intestinal stimuli were studied to determine the frequency of spontaneous emptying during fasting (n = 18). 99mTc-EHIDA (2,6 diethylphenylcarbamoylmethyliminodiacetic acid) was used as the biliary tracer. The frequency of gallbladder emptying during fasting was 0.0045/min. Thus, in any 20 min period emptying occurred spontaneously in only about 1 in 11 volunteers. Significant emptying (greater than 5 per cent over 20 min) occurred in 8 out of 15 volunteers after sham feeding a sandwich (P less than 0.001 versus control), in 8 out of 15 volunteers after sham feeding a cooked meal (P = 1.0 versus sandwich sham feed, n.s.), in 6 out of 9 volunteers after gastric distension (P less than 0.001 versus control) and in 14 out of 14 volunteers after meal ingestion. The rate of emptying was significantly greater in the gastric distension and meal ingestion groups compared with other groups (P less than 0.05). However, the emptying rate after sham feeding was not significantly different from spontaneous gallbladder emptying (P greater than 0.05, n.s.). There was no significant difference in time to onset of emptying between the four stimulus groups (P greater than 0.05, n.s.). These results suggest that pre-duodenal stimuli can evoke gallbladder emptying in man, although the precise physiological significance of this phenomenon remains to be established.  相似文献   
12.
Anulus fibrosus in bulging intervertebral disks   总被引:1,自引:0,他引:1  
Yu  SW; Haughton  VM; Sether  LA; Wagner  M 《Radiology》1988,169(3):761-763
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks.  相似文献   
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Objective: A single oral dose of paracetamol (20 mg · kg−1) was given to 38 Chinese patients with non-insulin-dependent diabetes mellitus (NIDDM) who had either normal renal function or varying degrees of renal impairment, with creatinine clearances ranging from 4 to 123 ml · min−1 · 1.73 m−2. The plasma and urinary concentrations of paracetamol and its major metabolites were measured by high-performance liquid chromatography (HPLC). Results: The absorption and elimination of paracetamol were unaffected by renal impairment. However, the area under the plasma concentration time curve and the elimination half-life of paracetamol metabolites increased significantly with worsening renal insufficiency. Mean renal clearances of paracetamol and its conjugates were significantly reduced in these subjects. There was no evidence of altered metabolic activation with renal impairment. Conclusion: The results demonstrate that paracetamol disposition is minimally affected by diabetic nephropathy; however, extensive accumulation of conjugates may occur. Received: 2 September 1996 / Accepted in revised form: 11 December 1996  相似文献   
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The bleeding problems experienced by users of subdermal levonorgestrelimplants (Norplant) remain unexplained. The aim of the presentstudy was to investigate the oestrogen (ER) and progesteronereceptor (PR) distribution in levonorgestrel-treated endometrialbiopsies from 31 subjects recruited in Jakarta, Indonesia, andto compare the sex steroid receptor immunostaining with thatof endometrium from 58 normally cycling women from Melbourne,Australia. Sex steroid receptor immunoreactivity was additionallycompared with days of exposure to subdermal levonorgestrel,serum oestradiol and progesterone levels and days of bleedingduring a 90-day reference period. An immunohistochemical techniquewith an alkaline phosphatase anti-alkaline phosphatase (APAAP)detection system for use in formalin-fixed paraffin wax embeddedendometrial tissue was employed. Significantly greater meanimmunostaining scores of stromal PR were observed in Norplantcompared with control endometrium at all stages across the cycle.No significant correlations were demonstrated between sex steroidreceptor immunostaining and days of exposure to subdermal levonorgestrel,serum oestradiol or progesterone concentrations or days of bleedingduring a 90-day reference period. Whether the elevated stromalPR immunostaining in Norplant-treated endometrium is a consequenceof increased synthesis or reduced turnover of receptor remainsunclear. As yet it is undetermined whether increased PR immunoreactivitycorresponds to an increase in number of functional PR.  相似文献   
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Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats.  相似文献   
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Twelve Sardinian patients affected by histologically defined classic Kaposi's sarcoma (KS) were HLA-A, B, C and DR typed. Compared to 220 age and ethnically matched healthy controls, KS patients showed a significant increase in HLA-DR5 (66.6 vs 23.1%, P less than 0.001) and a considerable decrease in HLA-DR3 (8.3 vs 53.6%, P = 0.0055). No definite association was observed for other HLA antigens. These results confirm the existence of an HLA associated genetic control of KS susceptibility and support the hypothesis that HLA-DR5 plays the role of a predisposition marker while HLA-DR3 bears a genetic resistance to the disease.  相似文献   
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