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排序方式: 共有4423条查询结果,搜索用时 46 毫秒
41.
K Takeuchi K Matsubayashi S Kimura A Kawamoto T Ozawa K Shimada 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(7-8):549-553
Lacunes on brain MRI, causal blood pressure, 24-hour ambulatory blood pressure and common carotid blood flow measured by the doppler method were studied in 31 elderly patients with Parkinson's disease (mean age 67.5 +/- 7.3 years). Nineteen patients with Parkinson's disease (61%) had at least one lacune. Patients with lacunes (P(+)) were significantly higher in age than patients without lacune (P(-)). The difference of casual blood pressure between patients in the two groups was not significant. On the other hand, the average of ambulatory blood pressure measurements during a 24-hour period was significantly higher in the P(+) group than in the P(-) group. The average of carotid blood flow was also significantly lower in the P(+) group than in the P(-) group, however, after adjustment for age, the difference between them became insignificant. In conclusion, the incidence of silent lacunes on brain MRI was fairly common in elderly patients with Parkinson's disease. A high average 24-hour ambulatory blood pressure was suggested to be one of the risk factors of lacunar stroke in elderly cases of Parkinson's disease. The concept of "combine type" in Parkinsonism was supposed to be suitable as well as in senile dementia of Alzheimer type. 相似文献
42.
K Matsubayashi S Kimura T Iwasaki K Okumiya T Hamada M Fujisawa K Takeuchi T Kawamoto T Ozawa 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(11):823-828
Visual analogue scale of happiness (VAS-H) was applied to elderly Himalayan highlanders to investigate the influence of life-style and socio-cultural background on subjective happiness. The score of "VAS-H" and neuropsychological function tests in 733 Himalayan highlanders who belonged to 5 separate villages were compared with those in 313 Japanese elderly subjects. The places of study consisted of 4 villages (Khalimabad; K, Gulmit; G, Pasu; P, Shimshal; S) in Hunza area in Pakistan, and Namche Bazar; N in Nepal. Degree of modern civilization was highest in K, followed by N, G, P and lowest was that in S by historical and sociological aspects. The mean VAS-H sore in Himalayan highlanders and the degree of modern civilization in the area was in inverse proportion. Himalayan elderly women showed a significant lower score on VAS-H compared with elderly Himalayan men or elderly Japanese subjects. The VAS-H score in the Japanese elderly correlated significantly with the stability of posture and walk, and that of Himalayan highlanders correlated significantly with manual skill. In conclusion, the life style or socio-cultural background strongly affected subjective happiness in the elderly. The VAS-H was useful in comparing subjective happiness in different cultures. 相似文献
43.
Incidental brain lesions on magnetic resonance imaging and neurobehavioral functions in the apparently healthy elderly. 总被引:9,自引:0,他引:9
K Matsubayashi K Shimada A Kawamoto T Ozawa 《Stroke; a journal of cerebral circulation》1992,23(2):175-180
BACKGROUND AND PURPOSE: Controversies exist whether incidental neuroradiological brain lesions in the elderly are associated with depressed neuropsychological function. To address this important issue in a cross-sectional study, we related brain lesions on magnetic resonance imaging to a variety of cognitive and neurobehavioral function tests in an independent, normal elderly population. METHODS: We studied 73 independent asymptomatic elderly individuals (mean +/- SD age 70 +/- 6 years) to determine the relations between degree of brain atrophy, location and number of "lacunes," and grade of periventricular hyperintense lesions with a variety of cognitive and neurobehavioral function scores. RESULTS: We found that severity of neuroradiological changes increased while neuropsychological function scores declined with age. After adjustment for the effect of age, advanced periventricular hyperintensities, but not brain atrophy or patchy "lacunar" lesions, were associated with declines in all neuropsychological functions tested. CONCLUSION: We conclude that incidental advanced periventricular diffuse or patchy white matter changes may play a role in the development of cognitive and neurobehavioral impairments in apparently normal elderly persons. 相似文献
44.
Chromogenic anti-Xa activity procedures were developed for monitoring LMW heparins on the Automated Coagulation Laboratory 300 Plus (ACL, Instrumentation Laboratory) system. For daily monitoring, a "Routine" procedure was devised which allows accurate measurements between plasma levels of 0.1 and 1.0 u/ml LMW heparin. For lower levels a "Routine-Low" method was developed which assesses activities between 0.05 and 0.4 u/ml. Due to variabilities in dODs of individual baseline plasmas, levels below 0.05 u/ml might be inaccurate when pooled normal plasma is used to establish the reference curve. While levels less than 0.05 u/ml should rarely be encountered when monitoring LMW heparins for routine clinical use, pharmacokinetic studies require accurate measurements below that level. For this reason a "Research-High" and a "Research-Low" procedure was designed. For these procedures a study subject's own baseline plasma was used to establish the reference curve. The "Research-High" measures activities between 0.4 and 2.0 u/ml, the "Research-Low" between zero and 0.4 u/ml. The procedures have excellent within-run and inter-run coefficients of variation (less than 5%) and high levels of accuracies. Even inter-instrumental reproducibilities are less than 10%. Different manufacturers' LMW heparins can be analyzed by these assays. The procedures offer full automation, great cost-effectiveness due to lower reagent volumes, rapid turn-around time and great accuracy and reproducibility. 相似文献
45.
Toshiko Sawaguchi Yuri Ozawa Patricia Franco Hazim Kadhim Jose Groswasser Martine Sottiaux Sachio Takashima Hiroshi Nishida Andre Kahn 《Pathophysiology》2004,10(3-4):173-178
Background: Tyrosine hydroxylase (TH) is a specific marker for catecholaminergic neurones. Some reports have demonstrated a decrease of TH in the sudden infant death syndrome (SIDS) compared with controls. To further investigate this, the correlation between TH and sleep apnea was investigated here. Materials and methods: Among 27,000 infants studied prospectively to characterize their sleep–wake behavior, 38 infants died under 6 months of age. They included 26 cases of SIDS. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and the duration of sleep apnea were analyzed. The brain-stem material was collected and subjected to immunohistochemical studies for TH. The density of TH-immunoreactive neurons was measured in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla (VLM) in the medulla oblongata. Correlation analyses were carried out between the density of TH-immunoreactive neurons and the data from the sleep apnea studies. Results: There was no SIDS specific correlation between TH-immunoreactive neurons in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla in the medulla oblongata and the frequency and duration of sleep apnea. Conclusions: No significant association between the pathological data and the physiological data refers to TH-positive neurons in the medulla oblongata in SIDS victims. 相似文献
46.
Dr Masamichi Kimura Izumi Sato Yuko Shiratori Nobuki Sugawara Kazuhiro Ozawa Hideaki Yamabe 《Pathology international》1984,34(2):289-304
We carried out electron microscopic studies on renal tissues from 9 patients with IgA nephropathy. Electron dense deposits were present in the mesangial area in all cases, subendothelial deposits in 4, and subepithelial deposits in only one. In basement membrane, segmental swelling and rarefaction of basement membrane substance were observed. In some cases the degenerated basement membrane substance protruded through the dilated endothelial fenestration into capillary lumina. Focal splitting, attenuation, mouse eaten appearance, and herniation of basement membrane were seen in a high incidence. Mesangial cells possessed well developed rough endoplasmic reticulums and polysomes. In the peripheral areas of mesangial cell cytoplasm, there was accumulation of electron dense substance and this was occasionally continuously present in the mesangial matrix. There was segmental swelling of endothelial cell cytoplasm, resulting in loss of fenestration. Epithelial cells had well developed rough endoplasmic reticulums and polysomes. Segmental foot process fusion was seen, and these processes, regardless of fusion, became electron denser in the area close to the basement membrane. Multivesiculated bodies were present in all cases in the epithelial cells and in 7 cases in the endothelial cells. Spherical microparticles were present in 3 cases in the urinary space or between the basement membrane and the epithelial cells. 相似文献
47.
Repair of infarcted myocardium mediated by transplanted bone marrow-derived CD34+ stem cells in a nonhuman primate model 总被引:6,自引:0,他引:6
Yoshioka T Ageyama N Shibata H Yasu T Misawa Y Takeuchi K Matsui K Yamamoto K Terao K Shimada K Ikeda U Ozawa K Hanazono Y 《Stem cells (Dayton, Ohio)》2005,23(3):355-364
Rodent and human clinical studies have shown that transplantation of bone marrow stem cells to the ischemic myocardium results in improved cardiac function. In this study, cynomolgus monkey acute myocardial infarction was generated by ligating the left anterior descending artery, and autologous CD34(+) cells were transplanted to the peri-ischemic zone. To track the in vivo fate of transplanted cells, CD34(+) cells were genetically marked with green fluorescent protein (GFP) using a lentivirus vector before transplantation (marking efficiency, 41% on average). The group receiving cells (n = 4) demonstrated improved regional blood flow and cardiac function compared with the saline-treated group (n =4) at 2 weeks after transplant. However, very few transplanted cell-derived, GFP-positive cells were found incorporated into the vascular structure, and GFP-positive cardiomyocytes were not detected in the repaired tissue. On the other hand, cultured CD34(+) cells were found to secrete vascular endothelial growth factor (VEGF), and the in vivo regional VEGF levels showed a significant increase after the transplantation. These results suggest that the improvement is not the result of generation of transplanted cell-derived endothelial cells or cardiomyocytes; and raise the possibility that angiogenic cytokines secreted from transplanted cells potentiate angiogenic activity of endogenous cells. 相似文献
48.
Ishikawa-Sakurai M Yoshida M Imamura M Davies KE Ozawa E 《Human molecular genetics》2004,13(7):693-702
An intracellular protein, dystrophin, plays an important role in keeping muscle fibers intact by binding at its N-terminal end to the subsarcolemmal cytoskeletal actin network and via its C-terminal end to the transmembraneous protein beta-dystroglycan. Duchenne muscular dystrophy is caused by the loss of dystrophin, which can result from the loss of this binding. The N-terminal part of the latter binding site of dystrophin has been well documented using overlay assay and X-ray diffraction assays. However, the binding site at the C-terminal region of dystrophin has not been examined in detail. In the present work, we report a detailed analysis of the C-terminal binding domain as follows. (1). The full binding activity corresponding to the effective binding in vivo is expressed by the dystrophin fragment spanning amino acids 3026-3345 containing the ZZ domain at the C-terminus. Determination of this binding range is important not only for understanding of the mechanism of dystrophy, but also useful for the design of truncated dystrophin constructs for gene therapy. (2). The ZZ domain binds to EF1 domain in the dystrophin fragment to reinforce the binding activity. (3). The cysteine 3340 in the ZZ domain is essential for the binding of dystrophin to beta-dystroglycan. A reported case of DMD due to missense mutation C3340Y may be caused by inability to fix dystrophin beneath the cell membrane. (4). The binding mode of utrophin is different from that of dystrophin. The difference is conspicuous concerning the cysteine residues present in the ZZ domain. 相似文献
49.
Matsuura-Sawada R Murakami T Ozawa Y Nabeshima H Akahira J Sato Y Koyanagi Y Ito M Terada Y Okamura K 《Human reproduction (Oxford, England)》2005,20(6):1477-1484
BACKGROUND: Cultures of human endometrial tissue are useful for analysing the mechanisms underlying the menstrual cycle. However, long-term culture of endometrial tissue is difficult in vitro. Xenotransplantation of normal human endometrial tissue into immunodeficient mice could allow prolonged survival of the transplanted tissues. METHODS: Proliferative-phase endometrial tissue samples from three women were transplanted into the subcutaneous space of ovariectomized, immunodeficient, non-obese diabetic (NOD)/severe combined immunodeficiency (SCID)/gammaC(null) (NOG) mice. The mice were treated with 17beta-estradiol (E2) for the first 14 days after transplantation, followed by E2 plus progesterone for the next 14 days. The transplants were investigated morphologically and immunohistochemically at various times after implantation. RESULTS: The transplanted tissues contained large numbers of small glands, pseudostratification of the nuclei and dense stroma after treatment with E2 alone. After treatment with E2 plus progesterone, subnuclear vacuolation, luminal secretion and decidualization of the stroma were observed. When the hormone treatment ceased, tissue destruction occurred and the transplants returned to the proliferative phase. Lymphocytes were identified immunohistochemically: the numbers of CD56-positive and CD16-negative cells increased significantly in the stroma during the late secretory phase (day 28). CONCLUSIONS: Human endometrial tissue transplanted into NOG mice showed similar histological changes to eutopic endometrial tissue during treatment with sex steroid hormones for 1 month. Moreover, lymphocytes were produced in the transplanted human endometrial tissue. This system represents a new experimental model of the human endometrium in vivo. 相似文献
50.