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排序方式: 共有1143条查询结果,搜索用时 15 毫秒
1.
Toshio Imaizumi MD PhD Toshimi Honma MD PhD Yoshifumi Horita MD Ikuhide Kohama MD PhD Kei Miyata MD Maiko Kawamura MD Jun Niwa MD PhD 《Journal of neuroimaging》2006,16(3):236-242
BACKGROUND AND PURPOSE: Dot-like low intensity spots (dot-like hemosiderin spots: dotHSs) on gradient echo T2*-weighted MRI have been histologically diagnosed to represent old cerebral microbleeds associated with microangiopathies. They have also been correlated to the fragility of small vessels and the tendency to bleed. Therefore, a substantial number of dotHSs might be associated with a large-sized, deep intracerebral hematoma (ICH). On the other hand, dotHSs may reflect old microbleeds that did not enlarge to symptomatic size. METHODS: To investigate how dotHSs are related to the size (maximal diameter) of primary deep ICH, we analyzed the diameter and the number of dotHSs in 151 patients with deep ICH not associated with subarachnoid hemorrhage or intraventricular hemorrhage (75 males and 76 females, age ranged from 37 to 90 [65.7 +/- 11.3 years old] who were consecutively admitted to Hakodate Municipal Hospital. The hazard ratio (HR) for a maximal diameter of deep ICH < or =2 cm was estimated, using the number of dotHSs and risk factors for stroke. RESULTS: The number of dotHSs associated with the diameter < or =2 cm was 9.2 +/- 11.5, significantly larger than that with the diameter > or =2 cm (4.7 +/- 7.0, P= .012). Multivariate analysis revealed that a maximal diameter of deep ICH of < or =2 cm was found in patients with dotHS (HR, 3.7; 95% confidence interval [CI], 1.4-10.1; P= .009). CONCLUSION: Though small sample size limited the power of our analyses, these findings suggest that the number of dotHSs may be associated with a small diameter of deep ICH. 相似文献
2.
Felix Eckstein Maiko Matsuura Volker Kuhn Mathias Priemel Ralph Müller Thomas M Link Eva-Maria Lochmüller 《Journal of bone and mineral research》2007,22(6):817-824
In this study, we characterize bone microstructure, specifically sex differences, at multiple skeletal sites in 165 subjects >52 yr of age, using microCT technology in vitro. Significant sex differences are observed at the distal radius, femoral neck, and femoral trochanter, but not at the iliac crest, calcaneus, and lumbar vertebral body. Correlations in BV/TV between sites ranged from r = 0.13 to 0.56. INTRODUCTION: The goals of this study were (1) to assess potential sex differences of bone microstructure and their difference between skeletal sites and (2) to explore the relationship of trabecular microstructural properties between relevant skeletal sites. MATERIALS AND METHODS: Trabecular bone microstructural properties were measured in vitro in 165 subjects 52-99 yr of age using microCT. Defined volumes of interest (cylinders with 6 mm diameter and 6 mm length) were scanned at a resolution of 26 microm (isotropic) in six different anatomical sites: distal radius, femoral neck and trochanter, iliac crest, calcaneus, and second lumbar vertebral body. RESULTS: At the radius and femoral neck, trabecular bone displayed a more plate-like structure, thicker trabeculae, smaller separation/higher trabecular number, higher connectivity, and a higher degree of anisotropy in men than in women (p < 0.05). At the trochanter, men displayed more plate-like structure and thicker trabeculae (p < 0.05), but no differences in trabecular separation or other parameters compared with the women. At the calcaneus, iliac crest, and second lumbar vertebra none of the bone parameters displayed significant differences between sexes. The BV/TV at one site explained a range of only 2-32% of the variability at other sites. CONCLUSIONS: These results suggest that trabecular bone microstructural properties are remarkably heterogeneous throughout the skeleton. Significant differences between men and women are observed at some, but not at all, sites. The magnitude of sex differences in trabecular microstructure coincides with that of fracture incidence observed for some of the sites in epidemiological studies. 相似文献
3.
S Iwata Y Sato Y Kusumoto H Shiro H Akita S Nanri T Oikawa M Osano K Sunakawa 《The Japanese journal of antibiotics》1986,39(9):2407-2420
The effect of cefotiam (CTM) on neonates and premature infants was examined in basic and clinical studies. Minimum inhibitory concentrations of CTM against 190 clinically isolated strains kept by this department were investigated. This drug was found to have a strong antibacterial effect against Escherichia coli, Klebsiella spp., Proteus mirabilis and Streptococcus agalactiae, Staphylococcus aureus and Staphylococcus epidermidis, although some strains were resistant. The CTM was given to 0-3, 4-7, and greater than or equal to 8 day-old premature infants and neonates by intravenous injection at the dose of 20 mg/kg, and we studied changes in serum CTM levels over time. Mean serum CTM levels were 62.3 micrograms/ml at 15 minutes and 16.4 micrograms/ml at 6 hours after the injection, with the half-life of 3.6 hours, for the 0-3 day-old premature infants. They were 38.5 micrograms/ml at 15 minutes and 10.1 micrograms/ml at 6 hours, with the half-life of 2.9 hours, for the 0-3 day-old neonates. Those levels were 22.5 micrograms/ml at 15 minutes and 2.9 micrograms/ml at 6 hours, with the half-life of 1.9 hours, for the 4-7 day-old neonates, and 51.8 micrograms/ml at 15 minutes and 1.0 micrograms/ml at 6 hours, with the half-life of 1.1 hours, for the greater than or equal to 8 day-old neonates. The CTM was given to 0-3 and greater than or equal to 8 day-old premature infants and neonates by 1-hour intravenous drip infusion at the dose of 20 mg/kg, and changes in serum CTM levels after the infusion were followed. The 0-3 day-old premature infant (there was only one subject) had a peak serum CTM level of 21.0 micrograms/ml 1 hour after the start of the infusion (that is, at the time of its completion), with the level decreased to 8.6 micrograms/ml at 7 hours and the half-life was 5.4 hours. The mean peak serum CTM level in 0-3 day-old neonates were 36.7 micrograms/ml at 1 hour, which decreased to a mean of 7.0 micrograms/ml at 7 hours; the half-life was 2.3 hours.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
4.
Loss of mammalian Sprouty2 leads to enteric neuronal hyperplasia and esophageal achalasia 总被引:3,自引:0,他引:3
Taketomi T Yoshiga D Taniguchi K Kobayashi T Nonami A Kato R Sasaki M Sasaki A Ishibashi H Moriyama M Nakamura K Nishimura J Yoshimura A 《Nature neuroscience》2005,8(7):855-857
We report here that loss of the Sprouty2 gene (also known as Spry2) in mice resulted in enteric nerve hyperplasia, which led to esophageal achalasia and intestinal pseudo-obstruction. Glial cell line-derived neurotrophic factor (GDNF) induced hyperactivation of ERK and Akt in enteric nerve cells. Anti-GDNF antibody administration corrected nerve hyperplasia in Sprouty2-deficient mice. We show Sprouty2 to be a negative regulator of GDNF for the neonatal development or survival of enteric nerve cells. 相似文献
5.
Bogsan CS Novaes e Brito RR Palos Mda C Mortara RA Almeida SR Lopes JD Mariano M 《International journal of experimental pathology》2005,86(4):257-265
The mechanisms that govern giant cell (GC) formation in inflammatory, neoplastic and physiologic conditions are far from being understood. Here, we demonstrate that B-1 cells are essential for foreign-body GC formation in the mouse. GCs were analysed on the surface of glass cover slips implanted into the subcutaneous tissue of the animals. It was demonstrated that GCs are almost absent on cover slips implanted into the subcutaneous tissue of BALB/c or CBA/N X-linked immunodeficient mice. As these animals do not have B-1 cells in the peritoneal cavity, they were reconstituted with B-1 cells obtained from cultures of adherent mouse peritoneal cells. Results showed that in B-1-reconstituted animals, the number of GCs on the implant surface surpassed the values obtained with preparations from wild animals. In animals selectively irradiated (pleural and peritoneal cavities) to deplete these cavities of B-1 cells, GCs were also not formed. Enriched suspensions of B-1 cells grown in culture were labelled with [(3)H]-tymidine and injected into the peritoneal cavity of naive mice before implantation of glass cover slips. After 4 days, about 17% of mononuclear cells had their nuclei labelled, and almost 70% of GCs had one or more of their nuclei labelled when analysed by histoautoradiographic technique. A few GCs expressed an immunoglobulin M when analysed by immunostaining and confocal microscopy. Overall, these data demonstrate that B-1 cells are pivotal in the mechanisms of foreign-body GC formation in the mouse. 相似文献
6.
Furuta M Kose S Koike M Shimi T Hiraoka Y Yoneda Y Haraguchi T Imamoto N 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(5):429-441
Heat-shock induces a strong stress response and modifies all aspects of cellular physiology, which involves dynamic changes in the nucleocytoplasmic distributions of a variety of proteins. Many distinct nucleocytoplasmic transport pathways exist in eukaryotic cells, but how a particular transport pathway is regulated under different cellular conditions remains elusive. The finding of this study indicate that conventional nuclear import, which is mediated by importin alpha/beta, is down-regulated, while the nuclear import of 70 kD heat-shock cognate protein is up-regulated in heat-shock cells. Among the factors involved in the mediation of the conventional nuclear import, significant levels of importin alpha accumulate in the nucleus in response to heat-shock. An analysis of the behaviour of importin alpha with fluorescence recovery after photobleaching and fluorescence loss in photobleaching studies show that nuclear importin alpha becomes less mobile and its nucleocytoplasmic recycling is impaired in heat-shock cells. These data coincided well with biochemical and cytological studies. Our present data show that heat-shock induces the nuclear accumulation, nuclear retention, and recycling inhibition of importin alpha, resulting in the suppression of conventional nuclear import. This suggests a new regulatory mechanism for the adaptation of cells to environmental changes, such as heat-shock. 相似文献
7.
This study investigated retrospectively the thoughts people had of World War II, especially the Battle of Okinawa at that time, and their current evaluation of their own wartime experience. A questionnaire survey was conducted, and 217 older adults, 114 women and 103 men between 65 and 88 years old, participated. Results indicated that men generally had more negative feelings than women at the end of the war. And psychological damages caused by traumatic war memories seemed to have persisted in not a few individuals in spite of over half a century since the end of the war. However, others had been more positive and accepting toward their wartime experiences. This difference appeared to be related to qualitative differences of various experiences, as well as the person's age. It is argued that a vigorous approach will be necessary for this sort of study of Japanese war victims from a number of viewpoints. 相似文献
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