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PROBLEM: To assess the effect of seminal plasma (SP) of fertile and infertile men on leukocyte mitogenic response, and the capability of sperm cells to produce IL-1. METHODS: This study included four groups: fertile men (donors, normal), infertile men with azoospermia (azoo), oligo-terato-asthenozoospermia (OTA), and OTA with genital infection (OTA-inf). Mouse spleen cell proliferation in response to lipopolysaccharide (LPS) or Concanavalin-A (Con-A) was examined in the presence of SP from the above four groups. Supernatants (sup) and lysates (lys) of sperm cells from fertile and oligoteratoasthenospermic (OTA) men were evaluated for IL-1 bioactivity by specific bioassay. RESULTS: Seminal plasma (SP) of the four groups were shown to inhibit the mitogenic response of mouse spleen cells to LPS and Con-A. SP of fertile men was significantly more inhibitory than SP from infertile men. Sperm cells from fertile and OTA infertile men constitutively produced IL-1. Sperm cells of both groups produced similar levels of IL-1 as examined in the supernatants and lysates. CONCLUSIONS: Seminal plasma of fertile men had more inhibitory mitogenic activity than that of OTA. Sperm cells constitutively produce IL-1. It is possible that the factors involved in this inhibition are not only anti-proliferative immune factors. Cytokines and inhibitory factors of mitogenesis in the seminal plasma may be involved in the physiology and pathophysiology of sperm functions and thus affect male fertility.  相似文献   
3.
One hundred consecutive patients recovering from an acute myocardiai infarction underwent, prior to home discharge, signal-averaged electrocardiography (ECG), left ventriculography. and 24-hour Holter ECG recording. The signal-averaged ECG was recorded and analyzed using two procedures: the orthogonal bipolar XYZ lead configuration with a bidirectional filter: and a precordial unipolar lead configuration with a uonrecursive digital filter. An abnormal signal-averaged ECG was seen in 40% of patients with the XYZ system and in 30% of patients in the precordial method, abnormal ejection fraction (< 40%) in 24% of patients and high grade ectopy activity in 22%. During the 24-month follow-up period, 12 patients (12%) had an arrhythmic event defined as either sudden death (11 patients) or sustained ventricular tachycardia (1 patient). Neither the signal-averaged ECG with the XYZ configuration, the abnormal ejection fraction, nor the high grade ectopy were able to statistically predict a higher arrhythmic event rate. The signal-averaged ECG with the precordial configuration was able to statistically predict a higher arrhythmic event rate, P < 0.03; odds ratio = 3.96. The combination of the orthogonal XYZ configuration signal-averaged ECG with the ejection fraction (P < 0.01, odds ralio = 7.33), or with ejection fraction and Holter monitoring (P < 0.06. odds ratio = 6.17) was able to predict a higher arrhythmic event rate. The combination of the precordial configuration signal-averaged ECG with the ejection fraction (P < 0.002, odds ratio = 14.4), or with ejection fraction and Holter monitoring (P < 0.06. odds ratio =10) was able to better predict a higher arrhythmic event rate. The combination of a normal or abnormal signal-averaged ECG and ejection fraction gave a sensitivity, specificity, positive, or negative value prediction of arrhythmic events of 60%, 90.6%, 37.5%, and 96%, respectively. It must be emphasized that the number of arrhythmic events during the 2-year follow-up was small and further study is required to determine the true predictive value of each method for arrhythmic events.  相似文献   
4.
Gastric and oesophageal emptying in insulin-dependent diabetes mellitus   总被引:4,自引:0,他引:4  
Abstract Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 45 randomly selected insulin-dependent diabetics and in 22 control subjects. In the diabetics, the relationships between oesophageal emptying, gastric emptying, age, duration of diabetes mellitus, upper gastrointestinal symptoms, glycaemic control and the complications, autonomic neuropathy, peripheral neuropathy and retinopathy were examined. The lag period before solid food left the stomach was not significantly different in diabetics compared with control subjects, but the percentage retention of solid food at 100 min was greater ( P < 0.001) in the diabetic subjects. Both the early phase (percentage retention at 10 min) and the 50% emptying time for liquid gastric emptying were delayed ( P < 0.001) in the diabetic subjects. Of the diabetics, 58% had delayed gastric emptying of either the solid and/or the liquid meal; oesophageal emptying was delayed in 42%. Upper gastrointestinal symptoms correlated poorly with both gastric and oesophageal emptying. Oesophageal emptying, solid gastric emptying and the liquid 50% emptying time correlated with the severity of autonomic nerve dysfunction ( P < 0.05). The early phase of liquid emptying (retention at 10 min) was significantly slower ( P < 0.05) in patients with mean plasma glucose concentrations of > 15 mmol/l during the gastric emptying test and the lag period for solid emptying correlated with both the glycosylated haemoglobin and mean plasma glucose concentrations.  相似文献   
5.
The aim of this study was to define better the motor phenomena associated with the slowing of gastric emptying by a duodenal lipid infusion. Antral, pyloric and duodenal motility were recorded in 10 healthy subjects with a manometric assembly which incorporated multiple perfused side-holes and a sleeve sensor positioned astride the pylorus. The gastric emptying of a standard solid meal and the distribution of the ingesta between the proximal and distal stomach were monitored with a radionuclide technique. A triglyceride emulsion was infused into the duodenum for 45 min once 25% of the meal had emptied. The infusion caused significant slowing in the rate of gastric emptying (P less than 0.01). This slowing in gastric emptying was associated with the suppression of pressure waves in the distal antrum (P less than 0.01) and proximal duodenum (P less than 0.01), the induction of pressure waves isolated to a narrow pyloric segment (P less than 0.01), and a redistribution of ingesta from the distal to proximal stomach. These findings suggest that pressure waves isolated to the pylorus, changes in the intragastric distribution of ingested food, and changes in proximal duodenal motility may all act in concert with changes in antral motility to regulate the gastric emptying of solids.  相似文献   
6.
中亚干旱区存在的两个主要生态环境问题是:水资源短缺和土地沙漠化严重,因此需改善和加强生态环境问题的治理。目前中亚干旱区植被退化严重,土地荒漠化加剧,生态环境不断恶化。提出治理中亚干旱区主要生态环境问题的措施是进行"引里济咸"和"北水南调"工程,同时必须控制中亚各国人口增长速度。通过各项治理措施,中亚干旱区生态环境问题得到改善。只有中亚国家应共同努力采取有效措施解决区域性生态问题,社会经济和生态环境才能得到持续发展。  相似文献   
7.
Children's prosodically conditioned substitutions have been recently described in terms of syllable structure. In this paper we present an alternative analysis, based on the position of the consonant within the foot. We review data from a previous case study (Chiat, 1989) that provide evidence in favour of a foot domain account and against the syllable structure account. One consequence of this finding is that it may be unnecessary to postulate that intervocalic consonants are captured into the coda of the previous syllable. While we caution that more evidence is needed to further test the foot and syllable accounts, we suggest that the foot be considered as a locus of substitution errors in phonology‐disordered children.  相似文献   
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The contribution of the pulsatile nature of gastric emptying to small intestinal feedback mechanisms modulating antropyloroduodenal motility and appetite is unknown. On separate days, eight healthy male volunteers (18-34 years) received randomized, single-blind, intraduodenal (ID) infusions of 10% Intralipid (2 kcal min(-1)), either continuously [CID], or in a pulsatile manner [PID] (5 s on/15 s off) and 0.9% saline (control) administered continuously, each at a rate of 1.8 mL min(-1) for 3 h. During each infusion, subjective ratings of appetite were assessed and antropyloroduodenal pressures recorded with a 16-lumen manometric assembly incorporating a pyloric sleeve sensor. Plasma cholecystokinin was measured from blood collected at regular intervals throughout the infusion. At the end of each infusion the manometric assembly was removed, subjects were offered a buffet meal and the energy and macronutrient content of the meal was measured. Both ID lipid infusions stimulated isolated pyloric pressure waves (IPPWs) (P < 0.001) and basal pyloric pressure (P < 0.01) and suppressed antral (P < 0.05) and duodenal (P < 0.05) pressure waves when compared to controls; there was no difference in the effects of CID and PID lipid on antropyloroduodenal pressures. Infusions of lipid significantly increased plasma CCK concentrations (P < 0.05) compared with saline, but concentrations were not different between the two modes of lipid delivery (P > 0.05, CID vs. PID). Both intraduodenal lipid infusions decreased hunger (P < 0.05), increased fullness (P < 0.05) and reduced energy intake (P < 0.05) when compared with controls; again there was no difference between CID and PID lipid. We conclude that at the infusion rate of similar 2 kcal min(-1), the acute effects of intraduodenal lipid on antropyloroduodenal pressures, plasma CCK concentration and appetite are not modified by a pulsatile mode of lipid delivery into the duodenum.  相似文献   
10.
The amino acid tryptophan (tryp) is a potent inhibitor of gastric emptying in both animals and humans. Animal studies suggest that this effect may be specific for the L-enantiomer. The effects of D- and L-tryptophan on gastric emptying, intragastric distribution and appetite in humans were evaluated. Ten volunteers ingested 300 mL of either L-tryp (50 mmol/L), D-tryp (50 mmol/L) or normal saline labelled with 99mTc sulfur colloid on three occasions, separated by between 3 and 7 days. Hunger and fullness were measured with a visual analogue scale at -2, 15, 30 and 60 min after ingestion of each drink. Saline emptied faster from the stomach than both L-tryp and D-tryp (P <0.05) and D-tryp emptied faster than L-tryp (P <0.005). Emptying from the proximal stomach was fastest for saline (P <0.05) and faster for D-tryp than L-tryp (P <0.005). Emptying from the distal stomach was faster for saline than both D- and L-tryp (P <0.05). A reduction in hunger (P <0.05) and a non-significant trend for an increase in fullness were observed after all three drinks. At 60 min, fullness was greater after L-tryp than after ingestion of D-tryp (P <0.01). These observations indicate that the effect of tryptophan on gastric emptying in humans is stereospecific, consistent with the concept that stereospecific receptors for tryptophan exist in the human small intestine.  相似文献   
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