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This study aimed to explore the mechanism involved in the synergistic purgative action of aloe-emodin anthrone and rhein anthrone, the active metabolites of sennoside C. Aloe-emodin anthrone and rhein anthrone, and their equimolar mixture, induced excretion of an approximately equal number of faeces by intracaecal administration at a dose of 23.2 μmol kg?1 in mice (= 10 standard dose). The number of wet faeces induced by aloe-emodin anthrone was less than those of rhein anthrone and the mixture. At the same dose, rhein anthrone and the mixture significantly stimulated large intestinal propulsion, though aloe-emodin anthrone had little stimulatory effect. Aloe-emodin anthrone and rhein anthrone decreased net water absorption but could not reverse it to the net secretion at 1/2 dose. The mixture significantly decreased net water absorption and reversed it to the net secretion at this dose. These anthrones did not stimulate mucus secretion in the colon at 1/2 dose. We concluded that the synergistic purgative effect of aloe-emodin anthrone and rhein anthrone in mice results from synergistic stimulation of large intestinal transit and large intestinal water secretion.  相似文献   
3.
An ultrastructural study of the colonic mucosa was performed in four patients with antibiotic-associated haemorrhagic colitis and new findings are reported. Colonoscopy was performed and biopsy specimens were obtained within 24 h of the onset of bloody diarrhoea. Colonoscopy demonstrated diffuse oedematous and haemorrhagic mucosa with erosions and white coat. Light microscopy revealed mucosal haemorrhage and inflammatory cell infiltration. Ultrastructurally, platelet aggregation was frequently present in the lumina of colonic mucosal capillaries, causing engorgement of red blood cells in adjacent microvessels. Mild to severe damage was observed in capillary endothelial cells, including discontinuity of basement membranes, gaps between endothelial cells and the destruction of capillaries. There was no evidence of microvascular spasm. In conclusion, our findings suggest that antibiotics directly or indirectly cause microcirculatory disturbances, which result in tissue damage and haemorrhage, in the colonic mucosa.  相似文献   
4.
Synthesis of various serum proteins, such as albumin, prealbumin, α1-antitrypsin, transferrin and α-fetoprotein, by human and rat yolk sac tumors was studied by indirect immunofluorescence and immunoperoxidase techniques. These serum proteins were found to be present in the cytoplasm of tumor cells forming the lining of vitelline cysts, as well as Schiller-Duval bodies and vacuolated meshwork on histological sections. Two of these tumors were cultured. Immunopathological studies revealed that albumin, prealbumin, α1-antitrypsin, transferrin and α-fetoprotein were found in the cytoplasm of these cultured tumor cells. The immunofluorescence of these proteins was also found on the PAS-positive granules, which existed intra- and extra-cellularly.
The ability to synthesize these serum proteins of these tumor cells was not affected by tissue culture and was maintained during subcloning.
It was demonstrated by electron microscope ferritin antibody technique that α-fetoprotein was mainly synthesized on the ribosomes of the rough endoplasmic reticula of rat yolk sac tumor cells.  相似文献   
5.
A 13 month old boy was found to have severely reduced β-galactocerebrosidase activity suggesting infantile Krabbe disease. Clinically, the patient showed a progressive neurological deterioration with white-matter disease on radiological study. Axillary skin biopsy was performed to support the diagnosis. On electron microscopy, needle-like inclusions, which are the typical finding seen in the cytoplasm of astrocytes and Schwann cells in the classic infantile form, were present in eccrine sweat gland epithelial cells. This method is useful for diagnosis when nerve biopsy and biochemical analysis are not readily available.  相似文献   
6.
Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work-related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunode?ciency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2–3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV-injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.  相似文献   
7.
ABSTRACT Currently, clefts of the lip, alveolus, and palate are thought to be the most common congenital malformations. In this study, we examined 1,565 cases of clefts we treated over the last 18 years, in order to summarize the clinical features and to evaluate the treatment outcomes. This study involved 589 cleft lip (CL) cases, 576 cleft lip and palate (CLP) cases, 286 cases of cleft palate (CP), 81 cases of submucous CP and 33 cases of CL and submucous CP. The familial incidence was 11.1% (174 cases). Overall, the average incidence of associated congenital abnormalities was 27.9%. Approximately half of the patients with CP alone or with submucous CP were found to have additional congenital malformations. Standeard surgical techniques for unilateral and bilateral CL cases were the Skoog's and Millard's methods, respecively, which resulted in satisfactory outcomes. As a primary operation for CP, pushback procedure was performed using a partial mucosal flap from the palate. Using this procedure 96.5% of 455 cases achieved satisfactory nasopharyngeal closure. The main objective in the treatment of CL patients is not only the repair of growing tissues but also appropriate morphological, functional and psychological reconstruction for the purpose of correcting growth inhibitory problems caused by anatomical malposition. Surgical procedures for CP patients are designed to meet several needs: correction of anatomical abnormalities of the palate and pharynx, achievement of proper nasopharyngeal closure necessary for normal phonation, prevention of growth disturbances of the maxilla, improvements in hearing and auditory tube function, and normalization of occlusion.  相似文献   
8.
Abstract The present study examined the differences of self-ratings of 4h sleep in three states: L-WE, where the percentage of waking time and urinary epinephrine are low (< 20% waking time); H-W, where the percentage of waking time and epinephrine levels increase along the basal regression line as determined by a previous study (20–100% waking time and < 7 ng/min); H-E, where epinephrine levels increase more than expected from the basal regression line for the two parameters (> 7 ng/min). Eight healthy male subjects participated twice in a 4 h polysomnograph experiment with four types of sleep onset (total of 64 observations). In group L-WE (52 observations for eight subjects), there were no excessively negative feelings on sleep latency, sleep depth, and feelings of sleep compared with usual sleep according to the questionnaire. Subjective sleep diagrams in group L-WE were similar to polysomnographic findings. Thus, group L-WE was thought objectively and subjectively to have a good sleep state. Groups H-W (eight observations for four subjects) and H-E (four observations for two subjects) had negative feelings regarding sleep depth and feelings of sleep compared with usual sleep. Approximately half the group H-W underrated their sleep compared with objective diagrams, while all cases in group H-E remarkably underrated their sleep in the subjective diagrams. The state of remarkable adrenal medullary secretory activity seen in group H-E and that of the slightly increased activity shown in group H-W were included in poor sleep states objectively and subjectively.  相似文献   
9.
For investigation of the effects of Endothelin-1 (ET-1) on colonic mucosa, ET-1 (10–160 nmol/kg) was sprinkled on rat colonic mucosa under observation with a new electronic endoscopic system (TOSHIBA TRE-3000, Japan). A high dose of ET-1 induced complete obstruction of submucosal arterioles, but not venules, without affecting arterial blood pressure. The ET-1 -induced contraction of both vessel types was maintained for 50 min and was followed by intramucosal dot hemorrhages. In this experimental model, the effects of ET-1 on the mucosal microcirculation were further analyzed with a laser doppler blood flowmeter (LDF) during endoscopic observation. The maximum decrease in mucosal blood flow was to 20 % of the control value and this decrease was maintained for 20 min at a dose of 80 nmol/kg. An ETA receptor selective antagonist, FR139317 (800 nmol/kg), inhibited ET-1 -induced changes in endoscopic findings and LDF, shifting the concentration-response curve of LDF to the right. FR139317 is a potentially useful new therapy for inflammatory bowel diseases, conditions which have been reported to be associated with high local concentrations of ET-1. Our electronic-endoscopic system was demonstrated to be a useful basic research tool for studying gastrointestinal pathophysiology.  相似文献   
10.
A human tumor line serially transplantable in nude mice, originatingfrom a well-differentiated papillo-tubular adenocarcinoma ofthe stomach, was established. The growth of this tumor was enhancedby daily injection of C-terminal tetrapeptide gastrin into themice. Although there was little difference in histology, thegastrin-stimulated tumor had larger glandular spaces filledwith mucin-like substance than the control tumor. 3H-thymidine uptake of the gastrin stimulated tumor was higherthan that of control, as shown by microradiography and countingof radioactivity in tissue homogenates. The plasma membrane fraction of the tumor revealed positivebinding for gastrin and the cytosol fraction contained cyclicAMP dependent- and independent protein kinases. Incubation oftumor slices with gastrin caused a conformational change inthe enzymes. Therefore we conclude that this G4 tumor line xenotransplantablein nude mice is sensitive to gastrin in its trophic and secretorymechanisms.  相似文献   
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