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961.
Background A reduced rectal perceptual threshold has been reported in patients with irritable bowel syndrome (IBS), but this phenomenon may be induced by a comorbid psychological state. We evaluated the rectal pain threshold at baseline and after conditioning (repetitive rectal painful distention: RRD) in patients with IBS or functional abdominal pain syndrome (FAPS), which is an abdominal pain disorder, and in healthy controls, and determined whether rectal hypersensitivity is a reliable marker for IBS. Methods The rectal sensory threshold was assessed by a barostat. First, a ramp distention of 40 ml/min was induced, and the threshold of pain and the maximum tolerable pressure (mmHg) were measured. Next, RRD (phasic distentions of 60-s duration separated by 30-s intervals) was given with a tracking method until the subjects had complained of pain six times. Finally, ramp distention was induced again, and the same parameters were measured. The normal value was defined by calculating the 95% confidence intervals of controls. Results Five or six of the seven IBS patients showed a reduced rectal pain threshold or maximum tolerable pressure, respectively, at baseline. In all patients with IBS, both thresholds were reduced after RRD load, but they were reduced in none of the patients with FAPS. RRD significantly reduced both thresholds in the IBS group (P < 0.05), but it had no effect in the control or FAPS groups. Conclusions Rectal hypersensitivity induced by RRD may be a reliable marker for IBS. Conditioning-induced visceral hypersensitivity may play a pathophysiologic role in IBS.  相似文献   
962.
Anemia is common among young women, and iron deficiency is one of the leading causes. In Europe and the US, the iron fortification of flour increased oral iron intake and decreased anemia prevalence from 30% to 10%. The National Nutrition Survey in Japan revealed that anemia prevalence among young Japanese women is increasing; however, no nationwide preventive policy has been aimed at iron deficiency anemia. The endpoint of this study was the estimation of anemia prevalence among healthy Japanese woman, based on a large sample size. We collected data from the consecutive check-up examination records of apparently healthy women (n = 13,147). We defined hemoglobin lower than 12 g/dL as anemia, hemoglobin lower than 10 g/dL as severe anemia, and a mean corpuscular volume lower than 80 fl as microcytic anemia. Of the 13,147 persons, anemia was identified in 2331 (17.3 %), and severe and microcytic anemia in 438 (3.3 %) and 700 (5.2 %), respectively. Among women younger than 50 years, anemia was identified in 22.3 %, and 25.2 % of them had severe anemia. In conclusion, the prevalence of anemia and severe anemia among young women is high in Japan. Some action needs to be considered to improve women's quality of life.  相似文献   
963.
Background The etiology of pancreatic cancer remains largely unknown. We examined the association of pancreatic cancer deaths with menstrual and reproductive factors in a cohort study involving Japanese women. Methods A total of 63 273 women were followed up for mortality from 1988 to 1999. Information on menstrual and reproductive factors was obtained by a questionnaire survey at baseline. Cox proportional-hazards models were used to estimate the relative risks (RRs) and 95% confidence intervals (CIs) for death from pancreatic cancer in relation to menstrual and reproductive factors. Results During 631 401 person-years of follow-up, 154 women died from pancreatic cancer. Parity was not significantly associated with the risk of death from pancreatic cancer; the RR was 0.80 (95% CI, 0.31–2.11) for women with six or more births compared with women with zero or one birth. We found no significant overall association with other reproductive factors, including pregnancy, age at first birth, and menopause. The risk appeared to increase with increasing age at menarche; the RR was 1.49 (95% CI, 0.95–2.34) for women who had menarche after 16 years of age compared to those who had menarche before they were 15 years old. Conclusions Our prospective data indicate that menstrual and reproductive factors are not associated with the risk of death from pancreatic cancer among Japanese women.  相似文献   
964.
A 59-year-old woman was diagnosed with essential thrombocythemia in 1988 and had been treated with hydroxyurea, mitobronitol, busulfan, and ranimustine, in that order. Hepatosplenomegaly, low-grade fever, and body weight loss manifested, and a few blasts were noted in the peripheral blood studied in March 2002. A biopsied specimen of the bone marrow showed myelofibrosis but not a leukemia in August 2004. An abnormal karyotype with der(1; 13) appeared for the first time. She was treated with low-dose prednisolone. In January 2005, she experienced left hip joint pain, and magnetic resonance scanning showed a tumoral lesion in the femoral head. Histological diagnosis of the biopsied mass revealed that it was a granulocytic sarcoma, and radiotherapy was performed. In April 2005, bone scintigraphy showed multiple lesions. She became febrile and red blood cell transfusion-dependent with hepatosplenomegaly and a small number of circulating blasts. Intravenous cytarabine (low dose) and etoposide relieved the fever and hepatosplenomegaly; however, she developed a pathologic fracture of the right humerus. An additional karyotypic abnormality (7q22 deletion) was noted. She subsequently died of infection. Granulocytic sarcoma is very rare in essential thrombocythemia, and this patient may be the first reported case of essential thrombocythemia that developed multiple lesions and a pathologic fracture without transformation to overt leukemia.  相似文献   
965.
We report two cases of insulinoma in advanced age patients considered unsuitable for surgery, in whom single daily doses of octreotide successfully improved hypoglycemia and hyperinsulinemia. The biological half-life of octreotide is about 100 min, hence it is customary to use two or three administrations per day to prevent hypoglycemia in insulinoma patients. The first case was a 76-year-old woman who presented with hyperinsulinemic hypoglycemia. Computed tomography (CT) and magnetic resonance imaging did not identify a tumor in the pancreas but a 1.5-cm tumor was found in the pancreatic body on abdominal angiography and selective arterial calcium stimulation and hepatic venous sampling (ASVS) were compatible with insulinoma. The patient refused surgery, but was successfully treated with octreotide at 50 microg subcutaneous injection once daily. Since the treatment was started (1 year), she has not suffered hypoglycemia. Case 2 was an 85-year-old woman who presented with hyperinsulinemic hypoglycemia. CT identified a 1.5-cm tumor in the pancreatic uncus, but she was considered unsuitable for surgery due to advanced age, obesity and cardiopulmonary dysfunction. Octreotide at 100 microg subcutaneous injection once daily prevented further hypoglycemic attacks, but two months later, postprandial plasma glucose was elevated. Octreotide was gradually reduced to 50 microg once daily. Three years have passed since the treatment without any hypoglycemic attack. Successful treatment with octreotide once daily could be due to old-age-related slow metabolism and could be potentially considered as the treatment of choice for elderly patients with insulinoma especially those considered unsuitable for surgery.  相似文献   
966.
BACKGROUND: Many pathological conditions induce electrical remodeling, possibly through intracellular Ca2+ overload, but the currently available L-type Ca2+ channel blockers may be detrimental because of their global negative inotropic effects. METHODS AND RESULTS: To determine whether the L-type Ca2+ channel is identical throughout the heart, the distribution of the mRNAs and proteins comprising the L-type Ca2+ channel and its electrophysiological properties were analyzed in rat atria and ventricles. The mRNA of alpha2delta-2 (Cacna2d2) was more abundantly expressed in the atrium (approximately 5-fold) than in the ventricle. In contrast, alpha1C (Cacna1c) (Cav1.2) mRNA was significantly less abundant in the atrium. The level of the alpha1C (Cacna1c) (Cav1.2) protein was decreased (approximately 0.5-fold) and that of alpha2 delta-1 (Cacna2d1) was increased (approximately 2-fold) in the atrium compared with the ventricle. Although the peak ICa,L density showed no significant differences, voltage dependence of inactivation and activation of the current showed a more depolarized shift in the atrium than in the ventricle. CONCLUSION: These results indicate that in the rat heart the L-type Ca2+ channel differs between the atrium and ventricle with regard to gene expression and electrophysiological properties.  相似文献   
967.
INTRODUCTION: Diabetes mellitus is one of the significant independent risk factors for the development of atrial fibrillation (AF). However, the pathophysiological mechanisms of the relationship have not been fully elucidated. METHODS AND RESULTS: The genetic type II diabetes (GK) rats and their original (Wistar) ones were subjected to electrophysiological (n = 8 per group) and histological (n = 7 per group) studies. At 40 weeks old, when GK rats had significantly (P < 0.01) more increased plasma glucose and HbA(1c) values than Wistar rats, atrial electrical stimuli in the isolated-perfused hearts induced significantly greater number of repetitive atrial responses in GK rats than in Wistar rats (47.9 +/- 17.5 vs 3.1 +/- 1.3 beats, respectively, P < 0.01). GK rats showed significantly longer intra-atrial activation time than Wistar rats (18.3 +/- 0.4 ms vs 15.9 +/- 0.5 ms, P < 0.01) without any significant difference in the atrial refractoriness. The histological examination revealed significantly increased diffuse fibrotic deposition in GK rats atria compared with Wistar ones (P < 0.01). CONCLUSION: The present diabetic GK rat showed increased atrial arrhythmogenicity with intra-atrial conduction disturbance, and thus indicated that the structural remodeling of atrium characterized by diffuse interstitial fibrosis would be a major substrate for diabetes-related AF.  相似文献   
968.
969.
Dendritic cells (DCs) express multiple Toll-like receptors (TLR) in distinct cellular locations. Herpes simplex viruses (HSV) have been reported to engage both the surface TLR2 and intracellular TLR9 in conventional DCs. However, the contributions of these TLRs in recognition of HSV and the induction of proinflammatory cytokines in DCs remain unclear. Here, we demonstrate that a rare population of HSV, both in laboratory strains and in primary clinical isolates from humans, has the capacity to activate TLR2. This virus population is recognized through both TLR2 and TLR9 for the induction of IL-6 and IL-12 secretion from bone marrow-derived DCs. Further, we describe a previously uncharacterized pathway of viral recognition in which TLR2 and TLR9 are engaged in sequence within the same DC. Live viral infection results in two additional agonists of TLR2 and TLR9. These results indicate that in cells that express multiple TLRs, pathogens that contain multiple pathogen-associated molecular patterns can be detected in an orchestrated sequence and suggest that the innate immune system in DCs is optimized to linking uptake and degradation of pathogens to microbial recognition.  相似文献   
970.
The prevalence and risk factors for hepatitis delta virus (HDV) infection among Mongolian school children were assessed by detecting the antibody against HDV and HDV RNA, and through structured interviews. The study subjects consisted of 181 children with the past or ongoing hepatitis B virus infection who were investigated during the nationwide serosurvey conducted in 2004. The prevalence of antibody to HDV was 6.1%, with the proportion of 13.6% among hepatitis B surface antigen (HBsAg)-positive subjects, all of whom had HDV RNA. Multivariate logistic regression analyses showed that injections (> 11 times) (odds ratio [OR] = 8.31, 95% confidence interval [CI] = 1.28-54.07) and blood sampling (> 3 times) (OR = 5.34, 95% CI = 1.12-25.53) in health care settings, hospitalization (> 3 times) (OR = 6.20, 95% CI = 1.18-32.71), and cohabitating with patients with chronic hepatitis (OR = 4.57, 95% CI = 1.26-16.55) predicted the seropositivity for antibody to HDV. These results suggest that parenteral exposures in health care settings and household transmission are the main routes of HDV transmission among Mongolian children.  相似文献   
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