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排序方式: 共有4871条查询结果,搜索用时 15 毫秒
41.
Yu Nakamura Masatoshi Takeda Hideo Suzuki Hitoshi Morita Kunitoshi Tada Shiro Hariguchi Tsuyoshi Nishimura 《Mechanisms of ageing and development》1989,50(3):215-225
The age-dependent change in activities of seven lysosomal enzymes (cathepsin D, β-glucuronidase, acid phosphatase, acid/alkaline DNases and acid/alkaline RNases) was studied in four brain regions (cerebrum, hippocampus, pons and cerebellum) of Wistar rats. The activity of cathepsin D was significantly increased with aging in the four regions. The age-dependent change in activities of acid and alkaline DNases showed the characteristic regional difference, and the ratio of acid to alkaline DNases was increased with aging in all regions. Acid RNase showed the lowest activity in 18-month-old rats, and alkaline RNase activity was decreased with aging. The activity of β-glucuronidase was higher in 2-month-old rats in all of the regions studied. Acid phophatase showed no significant age-dependent change except in pons. The study demonstrated that all of the lysosomal enzyme activities do not change in parallel with aging, and that the age-dependent change showed the characteristic regional difference. 相似文献
42.
Yamashita H Noguchi Y Noguchi S Yamashita H Uchino S Watanabe S Ogawa T Murakami T 《Endocrine pathology》2005,16(1):41-48
Risk factors for distant metastasis were studied in 82 patients with follicular thyroid carcinoma (FTC). Metastases to either
the lung or bone existing at the time of presentation were confirmed by I-131 radio-iodine uptake in 10 patients. FTC with
an insular component was found in eight patients. Univariate analysis of 14 possible risk factors showed 7 to be statistically
significant: insular component, poorly differentiated carcinoma, trabecular component, serum thyroglobulin level before surgery,
patient age at the time of presentation, solid component, and vascular invasion (ranked by p values). After further analysis of the interrelation of the factors and of the logistic regression curves, we concluded that
presence of an insular component and patient age were the only independent risk factors. Distant metastasis was not detected
in any of the 27 patients ≤49 yr old. Among the 55 older patients (≥50 yr old), 5 of the 49 (10%) without an insular component
and 5 of the 6 (83%) with an insular component had distant metastasis. The remaining older patient with an insular component
but without distant metastasis showed a gradual increase in thyroglobulin levels after total thyroidectomy. 相似文献
43.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
44.
OBJECTIVES: To investigate if menopause and oophorectomy may represent different risk factors for bone resorption/loss. METHODS: The urinary levels of pyridinoline (Pyr) and deoxypyridinoline (D-pyr), the serum levels of type I carboxy-terminal pyridinoline cross-linked telopeptide (ICTP), and lumbar bone mineral density (BMD), were compared in 80 Japanese women after menopause or oophorectomy. These women were divided into four groups of 20 women each as follows: early postmenopausal stage (early physiologic menopause < 3 years before study entry); late postmenopausal stage (physiologic menopause > or = 3 years before study entry); early postoophorectomy stage (oophorectomy < or = 03 years before study entry); or late oophorectomy stage (oophorectomy > 3 years before study entry). RESULTS: Lumbar BMD was significantly lower in the late groups compared to their respective early groups and was lowest in the late postoophorectomy group. The ratio of D-pyr/creatinine (Cr) was not significantly different among the four groups. The ratio of Pyr/Cr was significantly higher in the early postoophorectomy subjects compared with either late group. The serum level of ICTP was significantly higher in the early postoophorectomy group compared to all other groups. CONCLUSIONS: These findings suggest that serum ICTP may be useful in detecting changes in bone resorption after oophorectomy and that women are at greater risk for bone resorption after oophorectomy than after physiologic menopause, although this difference appears to diminish with time. 相似文献
45.
Nakashima E Mabuchi A Kashimada K Onishi T Zhang J Ohashi H Nishimura G Ikegawa S 《American journal of medical genetics. Part A》2003,(3):253-256
We examined 12 Japanese patients with metaphyseal chondrodysplasia (MCD) for mutations in the ribonuclease mitochondrial RNA processing gene (RMRP), and identified four novel mutations in two patients with typical and atypical cartilage-hair hypoplasia (CHH), a form of MCD characterized by extra-skeletal manifestations including hypoplastic hair and defective immunity. A patient with typical CHH had a 17-bp duplication at +3 and a de novo 182G > A. The other patient with atypical CHH had a 17-bp insertion at -20 and a 218A > G. Expression analysis revealed that the allele with this insertion mutation in the promoter region silenced the gene. Spectrum analysis of the mutations and polymorphisms in RMRP showed marked difference between the Japanese and other ethnic groups. Such ethnic and phenotypic difference should be taken into account in mutation analysis of the gene. 相似文献
46.
47.
Shin-ichiro Shoda Akio Komenoi Tomochika Fujioka Yasunori Okumura Shiro Kobayashi 《Macromolecular chemistry and physics.》1996,197(2):633-640
Isopropoxyethyne (1a) and tert-butoxyethyne (1b) were polymerized using group 5 and 6 transition metal catalysts to give poly(isopropoxyethyne) (2a) and poly(tert-butoxyethyne) (2b) , respectively. The weight-average molecular weight (M?w) of the resulting poly(alkoxyethyne)s was up to 1.0 × 104. Among the transition metal catalysts, a tungsten alkoxide or a molybdenum alkoxide having low Lewis acidity were found to effectively promote the polymerization without causing side reactions. Poly(tert-butoxyethyne) was successfully converted to poly(β-ketone) 3 by acid hydrolysis of the tert-butyl vinyl moiety. 相似文献
48.
Shiro Kobayashi Tsutomu Mizutani Takeo Saegusa 《Macromolecular chemistry and physics.》1984,185(3):441-451
2-(Hydroxyphenyl)-2oxazolines(p- and n-isomers 1a and 1b ) were used for the synthesis of various polymers. Cationic polymerization of 2-methyl-2-oxazoline initiated with the N-methyl 2 -oxazolinium species 3 , Derived from 1 , Gave telechelic poly(N-acetylethylenimine) ( 5 ) having a hydroxyl group of different reactivity at both ends. Anionic polymerization of ethylene oxide induced by the lithium salt of 1, 7 , produced a poly(ethylene oxide) macromer, 9 , having a ringopening polymerizable 2-oxazoline group. The copolymer from 9 and 2-phenyl-2oxazoline, 10 , has been shown to have good properties as a nonionic polymeric surfactant in which the N-benzoylethylenimine main-chain behaves as a lipophilic group whereas the oxyethylene graftchains act as a hydrophilic group. Di-salt 11 derived from 1 was polymerized to give polymide 13 (“amphi-ionic polymerization”). 相似文献
49.
Detecting Candida albicans in human milk 总被引:1,自引:0,他引:1
Morrill JF Pappagianis D Heinig MJ Lönnerdal B Dewey KG 《Journal of clinical microbiology》2003,41(1):475-478
Procedures for diagnosis of mammary candidosis, including laboratory confirmation, are not well defined. Lactoferrin present in human milk can inhibit growth of Candida albicans, thereby limiting the ability to detect yeast infections. The inhibitory effect of various lactoferrin concentrations on the growth of C. albicans in whole human milk was studied. The addition of iron to the milk led to a two- to threefold increase in cell counts when milk contained 3.0 mg of lactoferrin/ml and markedly reduced the likelihood of false-negative culture results. This method may provide the necessary objective support needed for diagnosis of mammary candidosis. 相似文献
50.
Yu Nakamura Masatoshi Takeda Hideo Suzuki Hideyuki Hattori Kunitoshi Tada Shiro Hariguchi Shigeo Hashimoto Tsuyoshi Nishimura 《Neuroscience letters》1991,130(2):195-198
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease. 相似文献