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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Facilitating visuospatial attention for the contralateral hemifield by repetitive TMS on the posterior parietal cortex 总被引:2,自引:0,他引:2
Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC. 相似文献
982.
McLinden RJ Lewis B Michael NL Redfield RR Birx DL Kim JH 《Journal of human virology》1997,1(1):30-36
OBJECTIVE: To determine the relation between P53 tumor suppressor RNA expression and human immunodeficiency virus (HIV) disease progression. STUDY DESIGN/METHODS: A quantitative assay of P53 RNA expression was used to analyze a cohort of HIV-negative persons. The assay was then used in longitudinal and cross-sectional studies of HIV slow and rapid progressors. RESULTS: We demonstrate first that P53 expression in peripheral blood mononuclear cells from HIV-1-seronegative persons is minimal. Longitudinal studies in a small cohort of HIV-1-infected slow and rapid progressors reveal that rapid progressors seem to have greater P53 RNA expression over time. This was validated in a cohort of 26 HIV-1-infected persons in whom the expression of P53 RNA was significantly greater in persons with rapid progression of HIV-1 disease. CONCLUSION: These data suggest that P53 RNA expression may play a role in the pathogenesis of HIV-1 disease, though the mechanism of this interaction remains unknown. 相似文献
983.
984.
S S Yoon H D Youn C Suh Y J Bang S J Choi B K Kim N K Kim E C Kim 《Journal of Korean medical science》1987,2(4):255-258
One case of arthritis complicating leukemia is described in which leukemic cells were identified in synovial fluid by light microscopy. Although arthritis is a well-known manifestation of leukemia with an incidence of 13.5%, the pathogenesis often is unclear, and the direct demonstration of leukemic cells in synovial fluid has been very uncommon. A 16 year-old male patient was admitted due to left elbow joint pain and swelling. Synovial fluid examination revealed blast cells and this finding has directed to a final diagnosis of acute lymphoblastic leukemia. 相似文献
985.
Kim Sang Geon; Kedderis Gregory L.; Batra Renu; Novak Raymond F. 《Carcinogenesis》1993,14(8):1665-1670
Liver microsomal epoxide hydrolase (mEH) is active in the detoxificationof epoxide-containing carcinogens. The effects of thiazole andpyrazine, constituents of tobacco and tobacco smoke as wellas of a variety of foods, on the expression and regulation ofmEH were examined in rats (200 mg/kg body wt/day, i.p., 1/emdash3 days). Immunoblot analyses using rabbit anti-rat mEH antibodyrevealed a significant increase in mEH levels in hepatic microsomesisolated from either thiazole- or pyrazine-treated animals.Another protein (43 kd) cross-reacting with polyclonal mEH antibodywas found to be increased concomitantly following pyrazine treatment.Northern and slot blot analyses showed substantial increasesin mEH mRNA following either thiazole or pyrazine treatment.The level of mEH mRNA increased 17-fold at 24 h following thiazoletreatment, relative to control. Approximately 20- and 16-foldincreases in mEH mRNA were also observed at 48 and 72 h respectivelyfollowing treatment with pyrazine. The level of polymerase chainreaction (PCR)-amplified mEH DNA derived from poly(A)+ RNA wasclearly elevated following either thiazole or pyrazine treatmentrelative to that from untreated animals. Both sense and antisensestrands of PCR-amplified mEH DNA were cloned into an M13mpl9phage vector in order to examine the nucleotide sequences ofPCR-amplified mEH DNA derived from the poly(A)+ RNA isolatedfrom thiazole- or pyrazine-treated animals. Sequence analysesrevealed that the sequence of PCR-amplified DNA from the inducedmRNA was identical to that published for mEH cDNA. Epoxide hydrolaseactivity toward the hydrolysis of 2-cyanoethylene oxide (CEO),the epoxide metabolite of the rat carcinogen acrylonitrile,was not significant in hepatic microsomes from untreated rats,but was substantially induced by treatment with thiazole orpyrazine. Microsomal hydrolysis activity was heat-sensitiveand potently inhibited by l, l, l-trichloropropene-2, 3-oxide,indicating that mEH was the catalyst. The Vmax for the hydrolysisof CEO by hepatic microsomes from thiazole-treated rats (13.4nmol/min/mg protein) was 1.5-fold greater than that with microsomesfrom pyrazine-treated rats, whereas similar Km values ( 1 mM)were observed for both microsomal preparations. These kineticdata correlate well with the increases in mEH mRNA observedafter administration of thiazole or pyrazine to rats. Theseresults provide evidence that administration of thiazole orpyrazine induces mEH with a large increase in mEH mRNA, andthat the induced mEH catalyzes the hydrolysis of CEO. 相似文献
986.
Shigeru Fujimoto Makoto Takahashi Kokuriki Kobayashi Masanobu Kure Hiroshi Masaoka Haruo Ohkubo Shigeo Isaka Jun Shimazaki 《Surgery today》1993,23(12):1094-1098
A huge rectosigmoidal cancer which extended into the urinary bladder in a 64-year-old man is herein described. The tumor occupied the pelvic and lower abdominal cavities, while the rectosigmoid was totally obstructed. No hepatic or pulmonary metastasis was evident. The ventral and flank sides of the peritoneum in the right lower abdomen, right common iliac vessels, bilateral ureters, terminal ileum, cecum, ascending colon, and urinary bladder were all directly invaded by the tumor, but the aorta, sacrum, and lower rectum were free of cancer. Consequently, an anterior pelvic exenteration was carried out along with an ileal conduit and a right hemicolectomy. Immediately after the exenteration, intra-pelvic hyperthermochemotherapy was performed using a 46–47°C perfusate containing 40 g/ml of mitomycin C (MMC) and 200 g/ml of cisplatin (CDDP), for 90 min, in an attempt to prevent any further local recurrence. A right hemicolectomy and a permanent colostomy were done simultaneously with the hyperthermia treatment. After an uneventful postoperative course, the patient was prescribed adjuvant chemotherapy, i.e., two administrations of 17 mg/m2 and 21 mg/m2 of MMC, and ten doses of 710 mg/m2 of 5-fluorouracil (5-FU) followed by five doses of 535 mg/m2 of 5-FU. At the time of this writing, the patient is still alive without recurrence at 21 months after surgery. 相似文献
987.
M. F. Jarvis C. J. Burns H. W. Pauls A. Assal J. S. Kim D. L. Cheney R. D. Youssefyeh 《Calcified tissue international》1993,52(5):372-377
Summary The present studies characterize the binding of [14C]citric acid to synthetic hydroxyapatite (HA) crystals. [14C]Citric acid specifically bound to HA and was dependent upon the concentration of HA in the assay. The binding of [14C]citric acid to HA reached equilibrium within 20 min and remained stable for at least 90 min. Dissociation of bound [14C]citric acid was biphasic in nature since both rapid and more slowly reversible binding components were detected. Saturation experiments also indicated that [14C]citric acid labeled two recognition sites with different affinity (KdH=42 nM and KdL=24,000 nM) and density (BmaxH=161 fmol/g HA and BmaxL=8.8 pmol/g HA). Ligand competition experiments revealed that compounds that are known to readily bind bone (e.g., sodium pyrophosphate, methylene diphosphonic acid, etidronate) potently inhibited the binding of [14C]citric acid to HA, whereas compounds known to have poorer affinity for bone (e.g., oxalic acid and GABA) did not. Computer analysis of these inhibition curves revealed specific ligand interactions at two different affinity recognition sites. The present results indicate that [14C]citric acid binds discrete sites on synthetic HA in a fashion consistent with a specific labeling of the bisphosphonate recognition site. Analysis of the binding of [14C]citric acid to HA provides a useful method to further explore the structure activity relationships of novel compounds that have binding affinity for bone. 相似文献
988.
Kim H 《Modern healthcare》1990,20(39):43
A developer is about to break ground on a $6.2 million medical office building on land owned by a California hospital. The deal will result in a haven for referral physicians at no cost to the hospital, though it will forgo equity and some management control. 相似文献
989.
990.
Kim H 《Modern healthcare》1990,20(47):44
As the population of rural America ages, rural hospitals are seeing opportunities for new revenue in long-term care. To meet those needs, they are turning to tax-exempt revenue bonds, something they rarely used in the past, and private venture capital, an entirely new wrinkle. 相似文献