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1.
p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.  相似文献   
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We have determined the entire nucleotide sequence of the human immunoglobulin kappa locus, comprising a total of 1,010,706 nucleotides. The 76 Vkappa genes found by a hybridization-based approach and their classification in 7 families were confirmed. A Vkappa orphon located near the locus was also sequenced. In addition, we identified 55 novel Vkappa relics and truncated pseudogenes, which establish 5 new families. Among these 132 Vkappa genes, 46 have open reading frames. According to the databases and the literature, 32 unique Vkappa genes and 5 identical gene pairs form VJ-joints, 27 unique genes and 4 gene pairs are transcribed, and 25 unique genes and 4 gene pairs produce functional proteins. The Vkappa gene locus contains a 360-kb inverted duplication, which harbors 118 Vkappa genes. A comparison of the duplicated Vkappa genes suggests positive selection on the complementarity-determining regions of the duplicated genes by point mutations. The entire duplication unit was divided into 13 blocks, each of which has its distinct nucleotide sequence identity to its duplication counterpart (98.1 - 99.9 %). An inversion-mediated mechanism is suggested to generate the high-homology blocks. Based on the homology blocks and the mutation rates, the inverted duplication is assumed to have taken place approximately 5 million years ago. An orphon Vkappa gene near the kappa locus and a cluster of five Vkappa orphons on chromosome 22 have no counterparts within the kappa locus. This suggests possible mechanisms of the transposition of orphon Vkappa genes.  相似文献   
3.
Summary The gene for epidermal growth factor receptor (EGFR) has been localized to the p14-p12 region of human chromosome 7 by somatic cell hybridization and radioisotopein situ hybridization techniques. In this paper, we report the precise mapping of the EGFR gene to the band p12 of chromosome 7 using a novel method in which fluorescence images fromin situ hybridization and Q-banding are computer graphically merged. The novel procedure is described in detail.  相似文献   
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Complementary DNA clones for phosphoribosylpyrophosphate synthetase subunits I and II (PRS I and PRS II) were used to determine the chromosomal localization of the corresponding human genes. Southern blot analysis of genomic DNAs isolated from human placenta and a panel of humanmouse somatic cell hybrids revealed that the rat PRS I cDNA probe detected at least five human specific DNA segments (23, 20, 14.5, 6.7, and 4.3 kb) in BamHI digests. The 23-, 14.5-, and 6.7-kb DNA segments were detected only if the hybrids contained human chromosome X or translocation chromosome 7p + (7qter>7p22::Xq21>Xqter), indicating the location of these segments to Xq21-qter (PRPS1). The 20- and 4.3-kb DNA segments did not cosegregate with the other three segments, and spot blot hybridization analysis using flow-sorted human chromosomes indicated that these are the PRPS1-related genes (PRPS1L1 and PRPS1L2) and could be assigned to chromosomes 7 and 9, respectively. The human-specific PRS II cDNA probe revealed a BamHI DNA segment (17 kb), which segregated condordantly with the X chromosome but not with the PRPS1 gene. We surmise that the gene for PRS II (PRPS2) is located at a different region of the X chromosome, namely Xpter-q21.Preliminary report of this research was presented at Ninth International Workshop on Human Gene Mapping, Abstract supplement p. 5 (1987).  相似文献   
6.
SPECT with N-isopropyl-p-[I-123]iodoamphetamine were performed in a 81-year-old man with cerebral infarction. In the subacute phase, the radioactivity was increased in the infarct area where fogging effect and remarkable contrast enhancement was demonstrated in X-ray CT. The contralateral cerebellar hemisphere showed reduced activity due to crossed cerebellar diaschisis (CCD). In the chronic phase, the decrement of the activity in the infarct was observed. Increased activity in the subacute phase was thought to reflect the hyperemia in the infarct, while CCD suggested the decreased metabolic activity in the lesion. The coexistence of the hyperemia and the CCD indicates flow and metabolic uncoupling, which means "luxury perfusion". This case was also thought to demonstrate atypical findings of CCD in SPECT imaging.  相似文献   
7.
OBJECTIVE: Cerebral [18F]fluorodeoxy-D-glucose PET ([18F]FDG-PET) was used to visualize the lasting neuronal activation after repetitive transcranial magnetic stimulation (rTMS) over the left hand area of the primary motor cortex (M1HAND). BACKGROUND: Applied over M1HAND, rTMS has been shown to produce a modulation of corticomotor excitability beyond the time of stimulation itself. METHODS: Eight right-handed subjects underwent nonquantitative [18F]FDG-PET measurements during two experimental conditions: at rest and after focal subthreshold 5-Hz rTMS over the left M1HAND. In the post-rTMS condition, [18F]FDG was injected immediately after the administration of 1,800 magnetic pulses over the left M1HAND. Relative differences in normalized regional cerebral metabolic rate of glucose (normalized rCMRglc) between conditions were determined using a voxel-by-voxel Student's t-test and volume-of-interest (VOI) analysis. Analysis was a priori restricted to the M1HAND, the supplementary motor area (SMA), and the primary auditory cortex of both hemispheres. RESULTS: A 5-Hz rTMS of the left M1HAND caused a lasting relative increase in normalized rCMRglc within the M1HAND bilaterally and the SMA. The magnitude and the topographic pattern of persisting relative rCMRglc increases within these motor cortical areas demonstrated considerable interindividual variations. CONCLUSIONS: Subthreshold 5-Hz repetitive transcranial magnetic stimulation (rTMS) over the hand area of the primary motor cortex is associated with a persisting neuronal activation in a distinct set of motor cortical areas beyond the time of stimulation. The current findings demonstrate that [18F]FDG-PET can localize and quantify regional net changes in synaptic cortical activity after rTMS and thus might elucidate the mechanisms underlying rTMS-associated therapeutic effects.  相似文献   
8.
Experimental evidence suggests that gonadal steroids regulate brain neurochemical systems associated with cognitive function, such as the cholinergic system. This study examines the effect of long-term postmenopausal hormone therapy on the brain concentrations of cholinergic synaptic terminals in women using single photon emission computed tomography and the radiotracer [(123)I]iodobenzovesamicol ([(123)I]IBVM). [(123)I]IBVM labels the vesicular acetylcholine transporter (VAChT) located in the presynaptic terminals of these neurons. Sixteen healthy women treated with hormone therapy since the menopause and 12 women not treated with hormones were studied. There were no significant differences in regional IBVM binding indexes between the 2 groups. The length of hormone replacement therapy correlated positively with VAChT binding indexes in multiple cortical areas (P < 0.05): frontal cortex (Spearman rank correlation: rho = 0.79), parietal cortex (rho = 0.62), temporal cortex (rho = 0.80), anterior cingulate (rho = 0.71), and posterior cingulate (rho = 0.63), but not in the basal ganglia (rho = 0.35; P = 0.2). An earlier onset of menopause in hormone-treated women was associated with higher VAChT indexes in the anterior cingulate (rho = -0.56; P = 0.02) and posterior cingulate (rho = -0.63; P = 0.01). The opposite was found in the posterior cingulate of women not treated with hormones (rho = 0.58; P = 0.04). Women treated with estrogen alone also showed higher VAChT indexes than women treated with estrogen and progestin in the posterior cingulate cortex (by Mann-Whitney U test: z = 2.42; P = 0.015). Although an overall effect of postmenopausal hormone therapy was not found, associations between an index of cortical cholinergic terminal concentrations and the length of hormonal replacement suggest that hormone therapy may influence the survival or plasticity of these cells in postmenopausal women. The data also suggest possible differential effects of estrogen and estrogen with progestin treatments in brain areas critical for cognitive processing.  相似文献   
9.
Lymphedema is a chronic progressive edematous disease that in the United States is most commonly related to malignancy and its treatment. Lymphaticovenular anastomosis is a recently introduced microsurgical treatment option for lymphedema that requires the identification and mapping of individual lymphatic channels. While nuclear medicine lymphoscintigraphy has been the primary imaging modality performed to evaluate suspected lymphedema, lymphoscintigraphy does not provide the spatial information necessary for presurgical planning. High‐resolution dynamic 3D magnetic resonance imaging (MRI) can noninvasively image abnormal lymphatic channels to both diagnose lymphedema and depict the location and number of individual lymphatic channels for surgical planning. MR lymphangiography can be performed at 1.5T or 3.0T using multichannel phased array surface coils. The main components of the exam are a heavily T2‐weighted 3D sequence to define the severity and extent of edema, a high‐resolution dynamic 3D gradient echo imaging after intracutaneous contrast injection to visualize lymphatic channels, and a delayed 3D gradient echo sequence after intravenous contrast to define veins. This article reviews the pathophysiology and microsurgical treatment of lymphedema, presents the imaging protocol used at our institution, and describes exam interpretation and the image postprocessing performed for surgical planning. J. MAGN. RESON. IMAGING 2015;42:1465–1477.  相似文献   
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