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排序方式: 共有2700条查询结果,搜索用时 31 毫秒
31.
Susumu Yamada Roko Kubota Kazuo Kubota Kiichi Ishiwata Tatsuo Ido 《Neuroscience letters》1990,120(2):191-193
This is the first study of micro-autoradiography (micro-ARG) for [18F]2-fluoro-2-deoxy-
-glucose ([18F]FDG). The localization of [18F]FDG was demonstrated in dendrites of neuron and also in the myelinated axon in mouse normal brain in vivo. The nucleolus was relatively free of label. The counted silver grain numbers in autoradiogram were linearly correlated to the 18F radioactivities in the specimen. The micro-ARG using positron emitting 18F is a very time-saving technique with 4 hours exposure compared with the conventional method using 3H- or 14C-labeled tracers. 相似文献
32.
E J Perlman G Stetten C M Tuck-Müller R A Farber W L Neuman K J Blakemore G M Hutchins 《American journal of medical genetics》1990,37(4):551-557
We report on monozygotic (MZ) twins who were discordant for phenotypic sex and Ullrich-Turner syndrome (UTS). The nonviable female was hydropic with cystic hygromas, ventricular septal defect, bicuspid aortic valve, polysplenia, intestinal malrotation, and small ovaries. The male was phenotypically normal. The monochorionic, diamniotic placenta had hydropic changes limited to the UTS infant's side. Skin samples from the infants and blood from their parents were obtained for cytogenetic and molecular analysis. Karyotypes of the twins were 45,X and 46,XY. Quinacrine polymorphisms on 7 chromosomes and RFLP analysis at 8 loci showed complete identity. MZ twins discordant for phenotypic sex have been described previously. Most of these show evidence of mosaicism in a 45,X patient with a normal 46,XY cell line, and a normal 46,XY male. While the issue of mosaicism in our case cannot be fully resolved, no mosaicism was found in 50 cells analyzed cytogenetically from each culture or by PCR analysis of a Y-specific sequence. The twins probably originated from either postzygotic nondisjunction or anaphase lag, followed or accompanied by twinning. The discordant placental morphology suggests an embryonic origin of at least part of the placental mesenchymal core. 相似文献
33.
A new-type titanium intervertebral spacer and its insertion device used in posterior lumbar interbody fusion 总被引:1,自引:0,他引:1
We have recently developed a new-type trapezoid mesh cage (TPM cage) together with an insertion device, which for use as a new titanium mesh intervertebral spacer in posterior lumbar interbody fusion (PLIF). The TPM cage has sufficient mechanical strength, a large contact area that gives good long-term stability, and preserves the initial disc height to provide good balance. The insertion device for the TPM cage is useful not only for handling the implant but also for controlling the implant insertion direction. The TPM cage and its insertion device are promising for use in PLIF. 相似文献
34.
Ndembi N Takehisa J Zekeng L Kobayashi E Ngansop C Songok EM Kageyama S Takemura T Ido E Hayami M Kaptue L Ichimura H 《Journal of acquired immune deficiency syndromes (1999)》2004,37(5):1641-1650
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown. 相似文献
35.
Mutsuo Furihata Eiji Ido Jun Iwata Hiroshi Sonobe Yuji Ohtsuki Jun Takata Taishiro Chikamori Yoshinori Doi 《Pathology international》1998,48(3):221-224
An autopsy case of a 58-year-old woman with massive cardiac Involvement of adult T cell leukemia/lymphoma (ATLL) is reported. She developed cardiac failure due to aortic and mitral regurgitation with cardiac infiltration of ATLL cells, and underwent replacement of both aortic and mitral valves. Studies of the cut-surfaces revealed diffuse thickening of the subendocardial wall of the left chamber with widespread whitish-brown tumor infiltrates. In the regions surrounding the replaced aortic and mitral valves there was also massive tumor cell infiltration. The tumor cells infiltrating the cardiac muscle wall were T cell in origin and exhibited Leu-3a (CD4)-positive immunoreaction. Ultrastructurally, tumor cells contained markedly indented nuclei and some were attached directly to the muscle cells. These findings suggest that this was an unusual form of ATLL with widespread involvement of the heart. 相似文献
36.
The rim sign: association with acute cholecystitis 总被引:1,自引:0,他引:1
In a retrospective analysis of 218 hepatobiliary studies in patients clinically suspected of acute cholecystitis, a rim of increased hepatic activity adjacent to the gallbladder fossa (the "rim sign") has been evaluated as a scintigraphic predictor of confirmed acute cholecystitis. Of 28 cases with pathologic confirmation of acute cholecystitis in this series, 17 (60%) demonstrated this sign. When associated with nonvisualization of the gallbladder at 1 hr, the positive predictive value of this photon-intense rim for acute cholecystitis was 94%. When the rim sign was absent, the positive predictive value of nonvisualization of the gallbladder at 1 hr for acute cholecystitis was only 36%. As this sign was always seen during the first hour postinjection, it can, when associated with nonvisualization, reduce the time required for completion of an hepatobiliary examination in suspected acute cholecystitis. 相似文献
37.
J. Perlman C. Gibson S.B. Pounds Z. Gu M.J. Bankowski R.T. Hayden 《Journal of clinical virology》2007,40(4):295-300
BACKGROUND: Detection and quantification of adenovirus (ADV) in peripheral blood specimens has become an increasingly important tool in the management of immunosuppressed patients. Investigators have described the use of whole blood (WB), peripheral blood mononuclear cells (PBMC), serum and plasma but no studies have compared the utility of these different sample types for use in a clinical diagnostic assay. OBJECTIVES: To determine the optimal blood compartment for quantitative real-time measurement of adenovirus in peripheral blood specimens. STUDY DESIGN: WB, PBMC, and plasma representing 338 samples from 148 patients were tested for ADV by quantitative real-time PCR (qrt-PCR) and the results compared for concordance of both qualitative sensitivity and viral load among positive specimens. RESULTS: There was no significant difference in qualitative sensitivity among the three tested specimen types. Quantitative values of WB and plasma were similar and tended to be greater than those found in PBMC samples. Comparison of consecutive positive samples within individual patients showed that viral loads tracked similarly over time, irrespective of the sample type tested. CONCLUSION: While WB and plasma do not offer a significant increase in sensitivity over PBMC, they may offer benefits in terms of reduced processing costs and laboratory turn around time. 相似文献
38.
Bystander CD8 T-cell-mediated demyelination is interferon-gamma-dependent in a coronavirus model of multiple sclerosis 总被引:1,自引:0,他引:1
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Mice infected with the coronavirus mouse hepatitis virus, strain JHM (JHM) develop a disease that shares many histological characteristics with multiple sclerosis. We previously demonstrated that JHM-infected mice that only have CD8 T cells specific for an epitope not in the virus develop demyelination on specific activation of these cells. Herein we show that this process of bystander T-cell-mediated demyelination is interferon-gamma (IFN-gamma)-dependent. The absence of IFN-gamma abrogated demyelination but did not change T-cell infiltration or expression levels of inflammatory cytokines or chemokines in the spinal cord. These results are consistent with models in which IFN-gamma contributes to CD8 T-cell-mediated demyelination by activation of macrophages/microglia, the final effector cells in the disease process. 相似文献
39.
We describe the association of brain death in an infant with a large cutaneous hemangioma of the forearm. The irreversible cerebral injury is presumed to be secondary to cerebral hypoperfusion as a result of a combination of systemic hypotension and a systemic vascular "steal" phenomenon caused by the cutaneous hemangioma. 相似文献
40.
Chen Sharon A. Perlman Andrew J. Spanski Noreen Peterson C. Matthew Sanders Steven W. Jaffe Robert Martin Mary Yalcinkaya Tamir Cefalo Robert C. Chescheir Nancy C. Menard Mary K. Mordenti Joyce 《Pharmaceutical research》1993,10(6):834-838
The pharmacokinetics of recombinant human relaxin (rhRlx) after intravenous (iv) bolus administration and the absorption of rhRlx after intracervical or intravaginal administration were determined in nonpregnant women. The study was conducted in two parts. In part I, 25 women received 0.01 mg/kg rhRlx iv. After a minimum 7-day washout period, these women were dosed intracervically (n = 10) or intravaginally (n = 15) with 0.75 or 1.5 mg rhRlx, respectively, in 3% methylcellulose gel. Part II was a double-blind, randomized, three-way crossover study in 26 women. At 1-month intervals, each woman received one of three intravaginal treatments consisting of 0 (placebo), 1, or 6 mg rhRlx in 3% methylcellulose gel. The serum concentrations of relaxin following iv administration were described as the sum of three exponentials. The mean (±SD) initial, intermediate, and terminal half-lives were 0.09 ± 0.04, 0.72 ± 0.11, and 4.6 ± 1.2 hr, respectively. Most of the area under the curve was associated with the intermediate half-life. The weight-normalized clearance was 170 ± 50 mL/hr/kg. The observed peak concentration was 98 ± 29 ng/mL, and the weight-normalized initial volume of distribution was 78 ± 40 mL/kg, which is approximately equivalent to the serum volume. If central compartment elimination was assumed, the volume of distribution at steady state (V
ss/W) was 280 ± 100 mL/kg, which is approximately equivalent to extracellular fluid volume. V
ss/W could be as large as 1300 ± 400 mL/kg without this assumption. After intravaginal administration of the placebo gel, endogenous relaxin concentrations were evident (i.e., 20 pg/mL) in 9 of the 26 women (maximum concentrations, 23–234 pg/mL). A similar proportion of women (approximately 35–40%) exhibited measurable serum concentrations of relaxin following intravaginal rhRlx treatment; this proportion increased to 90% following intracervical rhRlx treatment. For both routes of administration, the maximum serum concentrations of relaxin were usually within the range of values observed for endogenous relaxin, suggesting that the absorption of rhRlx was minimal. 相似文献