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91.
Shimamoto A Tanaka E Mizuno D Misawa S 《Research communications in molecular pathology and pharmacology》1999,104(3):265-276
Age- and sex-related changes in toluene metabolism by hepatic microsomes of male and female Sprague-Dawley (SD) rats (1 to 20 weeks) were investigated. A major metabolite of toluene, benzyl alcohol (BA), was measured by high-performance liquid chromatography (HPLC). At low substrate toluene concentrations (0.4 mM), in male rats, BA increased dramatically with development, reaching a peak at 5 weeks of age, rapidly decreasing thereafter. In female rats, BA increased dramatically with development at 3 to 5 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5 and 20 weeks of age, with BA products being higher in males than in females. At high substrate toluene concentrations (5.0 mM), in male rats, the BA formation pattern was similar to that at the low substrate concentration, although the rate of increase with age was slower. In female rats, a peak was obtained at 3 weeks of age, and then declined gradually to a low level. Gender differences were obtained at 5, 15 and 20 weeks of age, with BA products being higher in males than in females. These results indicate that toluene metabolism exhibits age and gender differences. 相似文献
92.
Effects of long-term administration of 1,2,3,4-tetrahydroisoquinoline (TIQ) on the striatal dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) were investigated in mice and rats. Striatal dopamine content significantly increased and DOPAC decreased after repeated administrations of TIQ at a dose of 50 mg/kg/day s.c. for 70 days in mice. In contrast, dopamine and DOPAC content did not show any significant change in rats. The ratio DOPAC/dopamine decreased significantly in mice treated with TIQ for 70 days. The results presented suggest that TIQ reduces the turnover rate of the nigrostriatal dopamine neurons after repeated administration for a long period in mice. 相似文献
93.
S. Kawaguchi M.D. T. Yamamoto A. Samejima K. Itoh N. Mizuno 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1979,35(3):511-518
Summary Changes in cerebellothalamic projections in kittens after neonatal hemicerebellectomy were studied by the retrograde and anterograde horseradish peroxidase (HRP)-tract-tracing methods. The number of cerebellar nuclear neurons labeled retrogradely with HRP injected into the ipsilateral VA-VL complex of the thalamus was much more numerous in neonatally hemicerebellectomized kittens than in intact kittens. Presumed terminals of ipsilateral cerebellothalamic fibers labeled anterogradely with HRP injected into the cerebellar nuclei were also distributed more densely and extensively in the thalamic areas, especially in the VA-VL complex, of hemicerebellectomized kittens than in the thalamic areas of the control kittens. These results are in good accordance with those obtained from the previous electrophysiological study (Kawaguchi et al., 1979) and offer corroborating evidence for axonal sprouting of cerebellothalamic neurons after neonatal hemicerebellectomy. 相似文献
94.
Makoto Yoshimura Isamu Sakurai Toshihiko Shimoda Kenji Abe Tadao Okano Toshio Shikata 《Pathology international》1981,31(4):711-717
Hepatitis B surface antigen (HBsAg) has been reported to be present in other organs than the liver.3,9 So far as our knowledge is concerned, however, any report of cases dealing with pancreatic diseases induced by hepatitis B virus (HBV) has not been described in the English and Japanese literature. We report an autopsy case with a pancreatic lesion characterized by damage of both exocrine and endocrine epithelial cells with inflammatory response, which were immunohistochemically found to be positive for HBsAg, and electron-microscopically to possess core-like particles In the nucleus and cytoplasm. 相似文献
95.
Motoneurons innervating the posterior belly of the digastric muscle were identified in the monkey, cat, dog, guinea pig and rat by the HRP method. After injections of horseradish peroxidase (HRP) into the posterior belly of the digastric muscle, two groups of HRP-labeled motoneurons were observed; the rostral group was seen as a small cluster of neurons in the lateral reticular area along the medial border of the descending root of the facial nerve, and the neurons of the caudal group were distributed among the ascending root fibers of the facial nerve. The distribution pattern of these neurons corresponded to that of the accessory facial nucleus neurons. The accessory facial nucleus was lacking in the rabbit in which the posterior digastric (PD) muscle is nonexistent. 相似文献
96.
A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage. 相似文献
97.
The present study has been attempted to establish a modified intravital microscope system for investigating murine lymphatic pumping activity in vivo and evaluate whether or not there is rhythmic pumping activity of murine mesenteric lymphatic vessels in vivo. We designed and constructed a custom organ chamber with a semicircular channel (8 mm in radius, 5 mm in width, 3 mm in depth), being suitable for the superfusing of murine mesentery in vivo. A marked lymphatic pumping activity was observed in the mesenteries of DDY mice. The maximal and minimal diameter and frequency in the pumping activity were 60.9 +/- 1.0 microm, 53.7 +/- 1.8 microm and 12.8 min(-1) (n = 5), respectively. Both NE (norepinephrine, 10(-8)-10(-6) M) and TEA (tetraethylammonium, 1-10 mM) caused dose-dependent constriction of the mesenteric lymphatic vessels in the mice. These findings suggest that a modified intravital microscope system with a specially designed and constructed edge-monitoring device enables us to investigate in vivo lymphatic circulation in murine mesenteries. 相似文献
98.
The plasminogen activation system reduces fibrosis in the lung by a hepatocyte growth factor-dependent mechanism 总被引:12,自引:0,他引:12 下载免费PDF全文
Hattori N Mizuno S Yoshida Y Chin K Mishima M Sisson TH Simon RH Nakamura T Miyake M 《The American journal of pathology》2004,164(3):1091-1098
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis. 相似文献
99.
Distribution of motoneurons supplying the tensor veli palatini (TVP) muscle was examined in the Japanese monkey (Macaca fuscata) by the retrograde horseradish peroxidase (HRP) method. Neurons labeled with HRP which was injected into the tensor veli palatini muscle were seen in the ventromedial aspects of the dorsolateral division of the trigeminal motor nucleus, at all rostrocaudal levels of the trigeminal motor nucleus. The vast majority of these TVP motoneurons were distributed around the margin, especially the dorsal margin, of the cluster of motoneurons which innervate the lateral pterygoid muscle. 相似文献
100.
K Mizuno 《Rinsho byori. The Japanese journal of clinical pathology》1992,40(2):152-155
To evaluate the utility of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) in the diagnosis of malignant ovarian tumors, preoperative CT of 23 patients and MRI of 10 patients with ovarian cancer were analyzed on the basis of their surgical findings. The stage suggested by CT and the stage revealed by surgery coincided in 16 cases (69.6%). The stage was underestimated by CT in 6 cases and overestimated in one case. The minimal size that could be detected by CT examination was 2 cm. The stage tended to be underestimated by CT. MRI examination with its unique soft tissue contrast in multiple planes is a detailed display of pelvic organs. However, the contrast of upper abdominal cavity was not so good, because of respiratory artifact. Sometimes there were false negative MRI in lymphatic metastasis. Therefore, MRI is more helpful in distinguishing local distension to pelvic organs than CT. 相似文献