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111.
Buoyancy and sedimentation of human X- and Y-bearing sperm   总被引:4,自引:0,他引:4  
The buoyant and sedimentation behaviors of human X- and Y-bearing sperm were examined in discontinuous density gradients of Nycodenz. The washed sperm placed at the bottom of the discontinuous density gradients of Nycodenz (23-50% in 3% steps) were centrifuged at 250 x g for various periods. The buoyant velocity of X-bearing sperm was faster than that of Y-bearing sperm. The sedimentation profiles of human sperm in the discontinuous density gradients of Nycodenz (4-20% in 2% steps) showed that X-bearing sperm sedimented faster than Y-bearing sperm. The separation of X- and Y-bearing sperm by means of centrifugation usually have been based on the assumption that smaller Y and larger X chromosomes might provide the difference in their apparent densities. The present results suggest that the separation cannot be due merely to a difference in their densities.  相似文献   
112.
In order to clarify the role of gastric inhibitory polypeptide (GIP) in an enteroinsular axis, 19 healthy mongrel dogs were divided into following groups: 5 normal dogs (N), 4 dogs with gastrojejunostomy (GJ), 5 dogs with duodenal fistula (D) and 5 vagotomized dogs (V). Four weeks after the operation glucose was administered orally or intraduodenally in a conscious state. In group D, glucose administration was repeated under atropine injection (A). Glucose-induced response of plasma GIP was exaggerated in all the groups compared with group N. The regression equation reported by Lauritsen and Moody was obtained in each dog from the ratio of plasma insulin to blood glucose and from plasma GIP. The slope of the regression line was elevated in group GJ and reduced in group V. However, groups D and A did not reveal any difference in the slope of the regression line compared with group N. From the present study, it might be concluded that the B-values in Lauritsen and Moody's equation indicates the sensitivity of the B cell in the pancreatic islet and that GIP secretion plays an important role in the glucose-induced insulin response even in the conditions with various surgical modifications.  相似文献   
113.
When heat-killed Propionibacterium acnes, a gram-positive anaerobe, is intravenously injected into mice followed by an intravenous injection of gram-negative lipopolysaccharide (LPS) 7 days later, most of the mice die of massive hepatic cell necrosis within 24 hours of LPS injection. Using this experimental model, acute hepatic failure was induced in mice, and the tryptophan metabolism in the liver, brain and kidney was studied. As a result, the tryptophan level was remarkably high in all three organs, and the metabolism of both the tryptamine pathway and serotonin pathway was induced. However, in the brain, the tryptamine metabolism was more induced compared to the serotonin, suggesting that the metabolites of tryptamine, may be involved in hepatic encephalopathy.  相似文献   
114.
115.
A reflectance spectrophotometric measurement was developed to analyze the microcirculation of the skin in real time. The relative absorption (RA) spectra were obtained from skin tissue 10 times per second using a spectro-multi-channel-photodetector system. In this system, white light was projected onto the skin of the back of the anesthetized rat and the spectrum of the reflected light between 450 and 643 nm was analyzed. Two absorption peaks at wavelengths of about 540 and 577 nm were observed, corresponding to the absorption peaks in the oxyhemoglobin (HbO2) spectrum. Either phlebotomy or the i.v. injection of norepinephrine (NE) reduced the RA spectrum. Peaks of the reduction in spectrum [(RA spectrum before the treatment) - (RA spectrum after the treatment)] were observed at about 540 and 577 nm. Injection of NE (0.75-48 ng/100 g B.W., i.v.) reduced the RA value at 577 nm dose-dependently, suggesting a decrease in the skin blood flow due to vasoconstriction. In addition, the content of HbO2 and capillary permeation were measured at the same time after the i.v. injection of Evans blue (EB) dye. As indices of HbO2 content and capillary permeation, RA changes at 540 and 610 nm (the latter is an absorption peak in the EB spectrum) were measured in real time, respectively. Both RA values increased dose-dependently after the intradermal injection of histamine (0.3-100 micrograms/site), suggesting the presence of vasodilation and an increase in permeability. The time at which the RA value for HbO2 reached a maximum was shorter than that for EB. These observations suggest that the method described here can detect changes in the HbO2 content and permeation of skin microcirculation at the same time, and in real time.  相似文献   
116.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients.  相似文献   
117.
A 49-year-old woman was referred to our hospital with complaints of epigastric colicky pain and high fever. Abdominal computed tomography and ultrasonography showed a solid tumor in the lower abdomen. Laparotomy revealed a neoplastic mass arising in Meckel's diverticulum; therefore, a segment of the ileum, including the tumor-possessing diverticulum, was resected with a lymph node dissection. A histologic examination confirmed the lesion to be leiomyosarcoma. In the English literature, 59 cases of leiomyosarcoma in Meckel's diverticulum were reported from 1941 to 1994. The majority of patients were in their 4th decade of life, with both sexes equally affected. The most frequent symptoms associated with this disease were abdominal pain with nausea, vomiting, and melena. The majority were larger than egg-size. Although Meckel's diverticulum is difficult to diagnose preoperatively, mesenteric arteriography may at times prove useful. The standard management of this particular tumor is wide segmental resection, including the tumor and diverticulum with lymph node dissection.  相似文献   
118.
119.
The authors examined the relationship between cerebral white matter changes and mental function, blood pressure in 39 neurologically normal aged (21 males, 18 females, mean age 75.0 years) who had no latent lesions on MRI images. The severity of cerebral white matter changes was estimated by T1 value images on MRI and was measured in the bilateral frontal lobe on an axial slice at the level of the basal ganglia and in the bilateral anterior, middle, and posterior portions on axial slices at the level of the body of the lateral ventricle. Mental function was measured by the Hasegawa's dementia rating scale (HDS) and Kohs' block design test (Kohs' test). The severity of cerebral frontal white matter changes increased significantly with age (p less than 0.05). However there was no significant correlation between the severity of cerebral white matter changes and HDS, Kohs' test. The severity of frontal white matter changes correlated with the mean arterial blood pressure (p less than 0.02). These results suggest that the severity of cerebral white matter changes is not related with mental function in the normal elderly, and that the severity of frontal white matter lesions is related with mean arterial blood pressure.  相似文献   
120.
MR appearance of parasymphyseal insufficiency fractures of the os pubis   总被引:1,自引:0,他引:1  
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant disease, so as not to misinterpret it as a chondroid tumor or bone metastasis.  相似文献   
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