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151.
508 Japanese patients with chronic liver disease, including chronic hepatitis, cirrhosis and hepatocellular carcinoma, and 500 controls matched for sex and age were studied. Antibody to hepatitis C virus (anti-HCV) alone was found in 233 (45.9%) patients and hepatitis B surface antigen (HBsAg) alone was present in 128 (25.2%) patients. Both anti-HCV and HBsAg were present in 18 (3.5%) patients. Anti-HCV was found in 8 (1.6%) controls and HBsAg was present in 4 (0.8%) controls. The prevalence of anti-HCV alone was 36.9% in chronic hepatitis, 49.0% in cirrhosis and 67.0% in hepatocellular carcinoma, respectively. The prevalence of anti-HCV increased with the progress of severity of liver disease. Anti-HCV was more prevalent than HBsAg both in cirrhosis and hepatocellular carcinoma (p less than 0.001). The prevalence of anti-HCV increased with age. Among patients under age 39 years, HBsAg was detected more often than anti-HCV, however, in those over age 50 years, anti-HCV was detected more often than HBsAg (p less than 0.001). It would appear that hepatitis C virus more than hepatitis B virus is a prominent cause of chronic liver disease among Japanese patients.  相似文献   
152.
To determine whether thromboxane A2 (TxA2) is involved in airway hyperresponsiveness induced by ozone exposure, we studied the effect of a specific TxA2 antagonist, AA-2414 on ozone-induced airway hyperresponsiveness in seven dogs. Airway responsiveness to inhaled methacholine was determined by modified Astograph (7 Hz oscillation method), and numbers of neutrophils in the peripheral blood, neutrophil counts in bronchoalveolar lavage fluid (BALF), the levels of TxB2 and 6-keto-Prostaglandin F1 alpha (6-keto-PGF1 alpha) in BALF were measured before and after ozone exposure, and after ozone exposure with pretreated AA-2414. Ozone exposure was carried out for 2 hr at an ozone level of 3.06 +/- 0.06 ppm (mean +/- SE). Airway responsiveness to inhaled methacholine increased significantly after ozone exposure (p less than 0.01), and the hyperresponsiveness induced by ozone exposure was inhibited significantly by pretreated AA-2414 (p less than 0.01). Numbers of neutrophils in the peripheral blood and neutrophil counts in BALF increased after ozone exposure, and these increase were not inhibited by pretreated AA-2414. There was no apparent change in the levels of TxB2 in BALF after ozone exposure and after ozone exposure with pretreated AA-2414, however the levels of 6-keto-PGF1 alpha in BALF decreased after ozone exposure and after ozone exposure with pretreated AA-2414 (p less than 0.1). These results suggest that TxA2 plays an important role in the development of airway responsiveness after ozone exposure in dogs, and ozone-induced airway hyperresponsiveness may not be associated with the hyperproduction of TxA2 but with the relative increase of TxA2 due to the decrease of PGI2.  相似文献   
153.
The cyanmethemoglobin (HiCN) method has been adopted as the international standard procedure for hemoglobin (Hb) determinations due to the accuracy and stability of result. However, the presence of potassium cyanide (KCN) and potassium ferricyanide (K3-Fe(CN)6) in the reagents has raised problems of laboratory and environmental pollution. In 1981, Oshiro and colleagues developed a cyanide free method of Hb determination that is based on a low toxicity compound Sodium Lauryl Sulfate (SLS). The SLS-Hb method provides stable SLS-Hb formation through the following steps. 1) Reaction of SLS to erythrocytic membrane (disruption of the erythrocytic membrane). 2) Conformation change of Hb by SLS. 3) Iron oxidation by oxygen (Fe2+----Fe2+). 4) Formation of stable SLS-Hb (coordination of SLS). The paper presents several findings on the reaction mechanism of the SLS-Hb method.  相似文献   
154.
We developed a mouse monoclonal antibody, S2n8, by immunizingmice i.p. with human decidual cells collected in the first trimesterof pregnancy. By indirect immunofluorescence staining of frozensections, S2n8 was found to react with decidual cells and endometrialstromal cells throughout the menstrual cycle, but not with endometrialglandular cells or with the endometrial surface epithelium.Judging from the fluorescence intensity, the antigen expressionon stromal cells was weak in the proliferative phase, and becamestronger in the secretory phase. Decidual cells in the firsttrimester of pregnancy and decidual cells at term showed strongexpression of this antigen. Indirect immunofluorescence stainingof enzymatically dispersed decidual tissue revealed that theS2n8 antigen was expressed on the decidual cell surface. Flowcytometric analysis of 12 freshly prepared stromal cell-enrichedcell suspensions showed that 74.8–94.2% (mean ±SD 86.1 ± 6.6%) of the cells carried the antigen. Theexpression of S2n8 antigen on cultured stromal cells was enhancedby the addition of oestradiol and/or progesterone. The antigenicmolecule was purified by immunoaffinity chromatography fromdecidua collected in the first trimester of pregnancy, and themolecular weight was estimated to be 140 kDa. These findingsindicate that the S2n8 antigen is a useful cell surface markerfor stromal cells/decidual cells and is associated with theirdifferentiation. cell surface antigen/decidual cells/endometrial differentiation/endometrial stromal cells/monoclonal antibody  相似文献   
155.
A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991.  相似文献   
156.
157.
The cricothyroid (CT) and the posterior cricoarytenoid (PCA) muscles in the larynx are activated by the laryngeal motoneurons located within the nucleus ambiguus; these motoneurons receive the laryngeal sensory information from the nucleus tractus solitarii (NTS) during respiration and swallowing. We investigated whether the neurons in the NTS projected directly to the laryngeal motoneurons, and what is the synaptic organization of their nerve terminals on the laryngeal motoneurons using the electron microscope. When wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the NTS after cholera toxin subunit B-conjugated HRP (CT-HRP) was injected into the CT muscle or the PCA muscle, the anterogradely WGA-HRP-labeled terminals from the NTS were found to directly contact the retrogradely CT-HRP-labeled dendrites and soma of both the CT and the PCA motoneurons. The labeled NTS terminals comprised about 4% of the axosomatic terminals in a section through the CT motoneurons, and about 9% on both the small (PCA-A) and the large (PCA-B) PCA motoneurons. The number of labeled axosomatic terminals containing round vesicles and making asymmetric synaptic contacts (Gray’s type I) was almost equal to that of the labeled terminals containing pleomorphic vesicles and making symmetric synaptic contacts (Gray’s type II) on the CT motoneurons. The labeled axosomatic terminals were mostly Gray’s type II on the PCA-A motoneurons, while the majority of them were Gray’s type I on the PCA-B motoneurons. These results indicate that the laryngeal CT and PCA motoneurons receive a few direct excitatory and inhibitory inputs from the neurons in the NTS. Accepted: 2 June 2000  相似文献   
158.
159.
We report a case of isolated unilateral absence of a pulmonary artery. The first clinical symptom that was manifested in the patient was recurrent hemoptysis, and subsequent angiography revealed that the main pulmonary artery was absent in the right lung, which was being fed only from the systemic circulation. Right pneumonectomy was performed, and neither the main pulmonary artery nor its remnant was detected in the resected right lung. Histologically, there were many muscular vessels in the resected lung, with intimal proliferation, or with plexiform-like lesions. The alveolar septum was moderately thickened and alveolar capillary vessels were dilated. We examined the alveolar capillary endothelial cells of the resected lung for immunoreactivity to thrombomodulin (TM) and von Willebrand factor (vWF). The endothelial cells were negative for TM and positive for vWF, while in the normal lung control group, these cells were positive for TM and negative for vWF. We considered that the hemodynamics of the systemic circulation in the resected lung caused the alteration of immunohistochemical characteristics in alveolar capillary endothelial cells.  相似文献   
160.
Restriction fragment length polymorphisms of the vitamin D receptor gene have recently been reported to be associated with changes in bone mineral density. Alterations in systemic calcium balance and Ca-regulating hormones such as 1,25(OH)2 vitamin D3 and parathyroid hormone have been demonstrated in essential hypertension. We investigated the relationship between polymorphisms of the vitamin D receptor gene and systemic Ca metabolism in patients with essential hypertension and in normotensives. We compared 147 subjects with essential hypertension and 100 normotensive control subjects. The genotype distribution and derived allele frequencies for the vitamin D receptor gene were similar in the two groups (genotype bb/Bb/BB and allele B/b: 60.1/32.6/7.2 and 0.24/0.76 in hypertensives vs. 56.0/36.0/8.0 and 0.26/0.74 in normotensive subjects). Serum concentrations of total Ca in the bb, Bb, and BB groups were, respectively, 4.5+/-0.3 vs. 4.5+/-0.4 vs. 4.4+/-0.5 mmol/l in normotensives and 4.6+/-0.3 vs. 4.6+/-0.4 vs. 4.4+/-0.5 mmol/l in hypertensives. Ionized Ca levels were 1.17+/-0.04 vs. 1.16+/-0.04 vs. 1.15+/-0.04 mmol/l in normotensives and 1.16+/-0.04 vs. 1.16+/-0.04 vs. 1.14+/-0.05 mmol/l in hypertensives, respectively. These results indicate that the BB genotype of the vitamin D receptor gene is associated with lower serum Ca levels but is not a useful predictive marker for the development of essential hypertension in Japanese subjects.  相似文献   
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