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101.
Influence of blood glucose levels on rat liquid gastric emptying   总被引:4,自引:0,他引:4  
The glycemic influence on liquid gastric emptying in rats was studied. Diabetic hyperglycemia was induced by streptozotocin intravenous injection seven days before the motility experiment. Some streptozotocin-treated rats further received a daily insulin injection (2.5 or 10 IU/kg). Immediate hyperglycemia was induced in a separate group of rats by continuous intravenous glucose infusion (44 or 88 mg/kg/min) 10 min before the experiment. Rats were killed 15 min after radiochromium feeding; then the radioactivity of stomach and small intestine were counted to obtain the gastric emptying value. Emptying in diabetic rats was delayed compared with controls (mean±se: 40.9±2.6% vs. 54.2±2.8%,P<0.01). Low-dose insulin treatment reversed the impairment, while high-dose treatment even enhanced emptying. Immediate hyperglycemia induced with two glucose infusions also inhibited gastric emptying. Present results indicate that hyperglycemia elicited with any hyperglycemic model is at least one of the important mechanisms to delay liquid gastric emptying.This study was supported by the National Science Council, Republic of China, grant NSC 84-2331-B-075-68.  相似文献   
102.
AIM: To investigate the effects of glutamine (GLN)-enriched diets before and GLN-containing total parenteral nutrition (TPN) after sepsis or both on the secretion of cytokines and their mRNA expression levels in splenocytes of rats with septic peritonitis. METHODS: Rats were assigned to a control group and 4 experimental groups. The control group and experimental groups 1 and 2 were fed a semipurified diet, while experimental groups 3 and 4 had part of the casein replaced by GLN which provided 25% of the total nitrogen. After rats were fed with these diets for 10 d, sepsis was induced by cecal ligation and puncture (CLP), whereas the control group underwent a sham operation, at the same time, an internal jugular vein was cannulated. All rats were maintained on TPN for 3 d. The control group and experimental groups 1 and 3 were infused with conventional TPN, while the TPN in experimental groups 2 and 4 was supplemented with GLN, providing 25% of the total nitrogen in the TPN solution. All rats were kiued 3 d after sham operation or CLP to examine their splenocyte subpopulation distribution and cytokine expression levels. RESULTS: Most cytokines could not be detected in plasma except for IL-10. No difference in plasma IL-10 was observed among the 5 groups. The IL-2, IL-4, IL-10, and TNF-α mRNA expression levels in splenocytes were significantly higher in experimental groups 2 and 4 than in the control group and group 1. The mRNA expression of IFN-γ was significantly higher in the GLN-supplemented groups than in the control group and experimental group 1. The proportion of CD45Ra+ was increased, while those of CD3+ and CD4+ were decreased in experimental group 1 after CLP was performed. There were no differences in spleen CD3+ lymphocyte distributions between the control and GLN-supplemented groups. CONCLUSION: GLN supplementation can maintain T-lymphocyte populations in the spleen and significantly enhance the mRNA expression levels of Th1 and Th2 cytokines and TNF-αin the spleen of rats with septic peritonitis.  相似文献   
103.
Urgent/emergent percutaneous transvenous mitral commissurotomy (PTMC) was performed in 10 patients (two men and eight women, aged 21 to 60 yr). All patients had arterial hypoxemia and four required mechanical respirators. PTMC was performed in the semi-recumbent position in four patients. The seven patients with pliable valves (group 1) achieved good hemodynamic and echocardiographic results after PTMC, but one died 2 wk later because of sepsis complicating preexisting pneumonitis. The two pregnant patients uneventfully delivered normal babies at term. There was continued clinical improvement in the six surviving patients at last follow-up at 11 to 39 mon (median 26). Of the three patients with calcified valves and severe subvalvular lesions (group 2), the premoribund patient in whom last-resort PTMC created severe mitral regurgitation died 3 days later of multiple organ failure. The other two patients underwent mitral valve replacement 1–6 days later because of lack of clinical improvement due to creation of severe mitral regurgitation and ineffective mitral valve dilation, respectively. In conclusion, urgent/emergent PTMC is feasible and safe. However, its outcomes are dictated by the status of diseased mitral valve and coexisting illness.  相似文献   
104.
Background Human minK protein is the β-subunit of IKs potassium channel and plays an important role in cardiac cellular electrophysiology. We investigated the association between human atrial fibrillation and the polymorphism of minK gene (38G or 38S) with a case-control study. Methods We included 108 patients with atrial fibrillation and 108 control subjects. The case patients and control subjects were matched regarding age, sex, presence of valvular heart disease, and presence of left ventricular dysfunction. The genotype of minK was determined with polymerase chain reaction and restriction fragment analysis. Results The results showed an association between the minK 38G allele and atrial fibrillation. The odds ratios for atrial fibrillation in patients with 1 and 2 minK 38G alleles were 2.16 (95% CI 0.81-5.74) and 3.58 (95% CI 1.38-9.27), respectively, when compared with patients without minK 38G allele. In a logistic regression model, the odds ratio for atrial fibrillation was 1.80 (95% CI 1.20-2.71, P < .0046) for patients with 1 more minK 38G allele. Conclusion We report the association between the minK 38G allele and clinical atrial fibrillation. Our findings suggest possible genetic control on the pathogenesis of atrial fibrillation. (Am Heart J 2002;144:485-90.)  相似文献   
105.
BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients.  相似文献   
106.
Ticlopidine-associated aplastic anemia   总被引:2,自引:0,他引:2  
 Serious hematologic complications associated with ticlopidine have been reported, including aplastic anemia. We report here an additional case of fatal aplastic anemia due to ticlopidine. A 66-year-old male patient developed fever and pancytopenia 2 months after ticlopidine was started. Despite the administration of granulocyte colony-stimulating factor (G-CSF) and broad-spectrum antibiotics, as well as aggressive red cell and platelet transfusions, the patient died 16 days after admission due to septic shock. Eighteen other cases of ticlopidine-induced aplastic anemia published in the English literature are also reviewed and presented here. Eight of the total 19 patients (including the one reported here) have died, mostly due to infection. Of the seven who received supportive treatment only, four had spontaneous recovery. Nine cases were treated with G-CSF or granulocyte-macrophage colony-stimulating factor (GM-CSF), and response was observed in only four of them. Several other cases were treated with high-dose corticosteroids or androgens; however, it was not possible to evaluate the efficacy of these treatments because of the limited number of cases. In the absence of satisfactory treatment for ticlopidine-induced aplastic anemia at present, it may be reasonable to try antilymphocyte globulin or cyclosporine. Also, great efforts should be made in the prevention and management of infection accompanying this disease. Received: 2 November 1997 / Accepted: 12 January 1998  相似文献   
107.
Body fat content and 25-hydroxyvitamin D levels in healthy women   总被引:15,自引:0,他引:15  
Obesity is associated with alterations in the vitamin D endocrine system. Lower levels of serum 25-hydroxyvitamin D (25-OHD) in morbidly obese individuals may be secondary to an alteration in tissue distribution resulting from an increase in adipose mass. Therefore, morbidly obese individuals are expected to need higher doses of vitamin D supplementation than the general population. However, it is still unknown whether adiposity (or percentage body fat) should be taken into consideration while assessing vitamin D requirements in the general population. To study the relationship between 25-OHD levels and percentage body fat content in healthy women, we studied 410 healthy women between 20 and 80 yr of age with body mass index ranging from 17 to 30 kg/m2. We analyzed the correlation between serum 25-OHD level and percentage body fat measured by dual energy x-ray absorptiometry. We also analyzed the influence of season, dietary vitamin D intake, age, and race on this relationship. The levels of serum 25-OHD inversely correlated with percentage body fat. The correlation was -0.13 (P = 0.013) after adjusting for race, age, season, and dietary vitamin D intake. In a multiple stepwise regression, race and season were found to have a major influence on serum 25-OHD (cumulative R2 = 0.34), and percentage body fat, although modest (additional R2 = 0.02), also had an independent statistically significant influence on serum 25-OHD levels. We conclude, percentage body fat content is inversely related to the serum 25-OHD levels in healthy women.  相似文献   
108.
Remedying patellofemoral osteochondral defects using clinical therapy remains challenging. Construct-based and cell-based regenerative medicine with in vitro physical stimuli has been progressively implemented. However, the effect of physical stimuli in situ in knee joints with degradable constructs is still not well-documented. Therefore, we studied whether it was practical to achieve articular cartilage repair using a poly(lactic-co-glycolic acid) (PLGA) construct in addition to early short-term continuous passive motion (CPM) for treatment of full-thickness osteochondral defects in the lower-weigh bearing (LWB) zone of the femoral trocheal groove. Twenty-six rabbits were randomly allocated into either intermittent active motion (IAM) or CPM treatment groups with or without PLGA constructs, termed PLGA construct-implanted (PCI) and empty defect knee models, respectively. Gross observation, histology, inflammatory cells, which were identified using H&E staining, total collagen and alignment, studied qualitatively using Masson’s trichrome staining, glycosaminoglycan (GAG), identified using Alcian blue staining, and newly formed bone, observed using micro-CT, were evaluated at 4 and 12 weeks after surgery. Repair of osteochondral defects in the PCI-CPM group was more promising than all other groups. The better osteochondral defect repair in the PCI-CPM group corresponded to smooth cartilage surfaces, no inflammatory reaction, hyaline cartilaginous tissues composition, sound collagen alignment with positive collagen type II expression, higher GAG content, mature bone regeneration with osteocyte, clear tidemark formation, and better degradation of PLGA. In summary, the use of a simple PLGA construct coupled with passive motion promotes positive healing and may be a promising clinical intervention for osteochondral regeneration in LWB defects.  相似文献   
109.
Although the Dexamethasone Suppression Test (DST) plays an important role in psychosomatic research, confounding factors limit the sensitivity and specificity of the DST. The aim of this study was to investigate the relationship between the intensity of daily life stressors and DST results in healthy participants after controlling the confounding factors. The subjects of this study consisted of 75 healthy volunteers. The intensity of daily life events was assessed using the Taiwanese version of the Recent Life Change Questionnaire (RLCQ). Neuroticism was assessed using the Maudsley Personality Inventory (MPI). The Dexamethasone Suppression Test (DST) was also performed. The regression model showed that daily life events (RLCQ score) were correlated significantly with cortisol level on day 1 and D% only in women. This finding implies that daily life events should be considered as an independent variable in women in further studies when the DST is applied.  相似文献   
110.
While stress may be a potential mechanism by which childhood threat and deprivation influence mental health, few studies have considered specific stress‐related white matter pathways, such as the stria terminalis (ST) and medial forebrain bundle (MFB). Our goal was to examine the relationships between childhood adversity and ST and MFB structural integrity and whether these pathways may provide a link between childhood adversity and affective symptoms and disorders. Participants were young adults (n = 100) with a full distribution of maltreatment history and affective symptom severity. Threat was determined by measures of childhood abuse and repeated traumatic events. Socioeconomic deprivation (SED) was determined by a measure of childhood socioeconomic status (parental education). Participants underwent diffusion spectrum imaging. Human Connectome Project data was used to perform ST and MFB tractography; these tracts were used as ROIs to extract generalized fractional anisotropy (gFA) from each participant. Childhood threat was associated with ST gFA, such that greater threat was associated with less ST gFA. SED was also associated with ST gFA, however, conversely to threat, greater SED was associated with greater ST gFA. Additionally, threat was negatively associated with MFB gFA, and MFB gFA was negatively associated with post‐traumatic stress symptoms. Our results suggest that childhood threat and deprivation have opposing influences on ST structural integrity, providing new evidence that the context of childhood adversity may have an important influence on its neurobiological effects, even on the same structure. Further, the MFB may provide a novel link between childhood threat and affective symptoms.  相似文献   
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