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1.
E Husebye  V Skar  T Hverstad    K Melby 《Gut》1992,33(10):1331-1337
Fifteen healthy old people mean age 84 years (range 80-91 years), were examined to assess the effect of advanced age on the microecology of the upper gastrointestinal tract. Twelve of 15 (80%) were hypochlorhydric with pH 6.6 (0.3) (mean (SEM) and a mean bacterial count of 10(8) colony forming units (CFU) per ml (range 10(5)-10(10)) in fasting gastric aspirate. Normochlorhydric subjects had low counts (< or = 10(1) CFU/ml). The microbial flora was dominated by viridans streptococci, coagulase negative staphylococci, and Haemophilus sp. Only one subject harboured significant concentrations of Gram negative bacilli with Escherichia coli (10(4-5) CFU/ml) and Klebsiella (10(4-5)). Strict anaerobes were not found. The total concentration of short chain fatty acids in gastric aspirate was 10.6 (2.9) mmol/l (mean (SEM). Absence of significant, intraluminal fermentation of xylose to CO2 was shown by the 14C-d Xylose breath test, and ambulatory manometry showed preserved fasting motility pattern of the small intestine. Serum immunoglobulins were normal. Advanced age is accompanied by fasting hypochlorhydria and colonisation with mainly Gram positive flora in the upper gut. Other factors than old age and fasting hypochlorhydria are required for colonisation with Gram negative bacilli.  相似文献   
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? The benefits of informing patients before undergoing surgery or other investigative procedures are clearly demonstrated in the literature. ? This study aimed to determine the amount and type of information given to patients before, during and after undergoing gastroscopy investigations. ? A survey approach incorporating structured interviews and structured observation was utilized. ? There were statistically significant differences between the information acquired by younger and older patients prior to, but not during or after, the procedure. ? Nurses appear to be the most important source of information for older patients while the information leaflet was perceived as the most important source of information for younger patients.  相似文献   
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Sublingual buprenorphine is a promising new treatment for opiate dependence, but its opioid agonist effects pose a risk for parenteral abuse. A formulation combining buprenorphine with the opiate antagonist naloxone could discourage such abuse. The effects of three intravenous (IV) buprenorphine and naloxone combinations on agonist effects and withdrawal signs and symptoms were examined in 12 opiate-dependent subjects. Following stabilization on a daily dose of 60 mg morphine intramuscularly, subjects were challenged with IV doses of buprenorphine alone (2 mg) or in combination with naloxone in ratios of 2:1, 4:1, and 8:1 (1, 0.5, or 0.25 mg naloxone), morphine alone (15 mg) or placebo. Buprenorphine alone did not precipitate withdrawal and had agonist effects similar to morphine. A naloxone dose-dependent increase in opiate withdrawal signs and symptoms and a decrease in opioid agonist effects occurred after all drug combinations. Buprenorphine with naloxone in ratios of 2:1 and 4:1 produced moderate to high increases in global opiate withdrawal, bad drug effect, and sickness. These dose ratios also decreased the pleasurable effects and estimated street value of buprenorphine, thereby suggesting a low abuse liability. The dose ratio of 8:1 produced only mild withdrawal symptoms. Dose combinations at 2:1 and 4:1 ratios may be useful in treating opiate dependence. Received: 9 February 1998/Final version: 8 May 1998  相似文献   
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Insulin resistance is often accompanied by elevated plasma triglycerides (TG) and a preponderance of small, dense low-density lipoprotein (LDL) particles. However, it remains unclear whether or not insulin resistance is related to LDL particle size, independent of plasma TG. We sought to determine the strength of the relationships among these variables in a group of overweight, nondiabetic men (N = 34; body mass index [BMI], 25 to 35 kg/m(2); age, 50 to 75 years), as well as to examine the possible relation between insulin sensitivity and oxidized LDL (oxLDL). We also examined the strength of the relationships between these lipid variables and estimates of insulin sensitivity using calculated indices based on fasting insulin and glucose concentrations. Insulin sensitivity (Si) was significantly associated with total TG (r = -0.61, P <.001), very-low-density lipoprotein (VLDL)-TG (r = -0.60, P <.001), and LDL size (r =.414, P <.05). LDL size was also significantly associated with TG (r = -0.73, P <.001), VLDL-TG (r = -0.73, P <.001), high-density lipoprotein-cholesterol (HDL-C) (r = 0.65, P <.001), the quantitative insulin sensitivity check index (QUICKI) (rho = 0.46, P <.01), and the homeostatic model for the assessment of insulin resistance (HOMA-IR) (rho = -0.45, P <.01). Si was a significant predictor of LDL size, with age and BMI also independent contributors to the variance in LDL size (R(2) = 0.172). However, when TG and HDL-C were added to the model, Si was no longer a significant predictor of LDL size. The correlation between Si and oxLDL was weak, but stastically significant (rho = -0.40, P =.02). These data suggest that the relation between Si and LDL size is largely mediated by plasma TG, and that Si is only weakly related to oxLDL in overweight, nondiabetic men.  相似文献   
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19-Nor-deoxycorticosterone (19-nor-DOC) is a naturally occurring, potent mineralocorticoid present in hypertensive animal models as well as man. To investigate 19-nor-DOC's regulation and possible pathogenesis in hypertension, urinary free (UF) 19-nor-DOC was measured in 14 hypertensives, correlated with other corticosteroids and systemic arterial blood pressure (BP), and compared to basal and ACTH-stimulated values in 8 normotensive subjects. Seven of the 14 hypertensives had low-renin hypertension, 2 had primary aldosteronism, 1 had an adrenal carcinoma, and another had acromegaly. These studies determined that: 1) although the mean UF 19-nor-DOC was not increased in hypertensives (588 +/- 180 vs. 428 +/- 122 ng/day), 2 low-renin hypertensives had quite elevated levels (2186 and 2018); 2) the UF 19-nor-DOC in hypertensives was correlated with BP but not with PRA, aldosterone secretion, plasma potassium, basal plasma cortisol, or 17-hydroxycorticosteroids; 3) likewise, in normotensives, UF 19-nor-DOC did not correlate with basal plasma cortisol, cortisol secretion, or 17-hydroxycorticosteroids excretion but did correlate after ACTH stimulation. Therefore, although 19-nor-DOC is activated by ACTH administration, it is not correlated with basal parameters of cortisol production, suggesting that factors other than ACTH regulate basal 19-nor-DOC secretion. Furthermore 19-nor-DOC is elevated in some hypertensive patients, and it is directly related to the elevation of mean systemic BP. This suggests that, although 19-nor-DOC could contribute to hypertensive disease in some individuals, it does not appear to be due to excess ACTH.  相似文献   
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Melby KK  Kvien TK  Glennås A 《Infection》1999,27(4-5):252-255
Summary Four cases of reactive arthritis (ReA) related to Helicobacter pylori (HP) are presented. These were identified by IgG, IgM and IgA ELISA tests performed on sera obtained from a 2-year prospective study on 186 patients with a clinical picture suggesting ReA as a possible diagnosis. If anti-HP IgM and IgA or IgG were positive, the case was considered related to HP. Three out of four HP ReA patients were originally classified as “possible ReA”, i.e. having a clinical picture of ReA but without any identified triggering microorganism. IgG antibodies against cagA and vacA were detected in three and two cases respectively. The HP ReA patients did not present with typical clinical or laboratory features differentiating them from ReA induced by Chlamydia trachomatis (N = 25) or enteropathogenic bacteria (N = 27). However, compared to findings in patients with ReA due to enteropathogenic bacteria the number of active joints was higher (six versus two), duration of arthritis longer (3.9 weeks versus 2 weeks) and the CRP (C-reactive protein) lower (43 versus 59). Our findings suggest that HP may be included in the list of possible arthritis triggering microbes. Received: May 5, 1999 · Revision accepted: June 21, 1999  相似文献   
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