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81.
Transrectal needle aspiration biopsy and core biopsy of the prostate were performed simultaneously on 88 men with prostatic nodules. Cytologic and histologic assessments were made in a blinded, independent fashion, and the results were compared. All patients with positive findings on aspiration also had positive findings on core biopsy, for a positive predictive value for aspiration of 100%. However, five negative and six "insufficient" results obtained by aspiration were positive on core biopsy, for a negative predictive value for aspiration of 88%. This experience support the use of needle aspiration as an initial diagnostic maneuver in the assessment of prostatic nodules.  相似文献   
82.
Two reliable techniques for the microvascular anastomosis of difficult-to-handle, thin-walled smaller vessels--"insert sutures first, tie later" and "loops on hanger"--are described.  相似文献   
83.
The records of 167 patients with grade 1 or 2 supratentorial pilocytic astrocytomas (41 patients), ordinary astrocytomas (91 patients), or mixed oligoastrocytomas (35 patients) diagnosed between 1960 and 1982 are retrospectively reviewed. The extent of surgical tumor removal was gross total or radical subtotal in 33 patients (20%) and subtotal or biopsy only in the remaining 134 patients (80%). Postoperative radiation therapy was given to 139 (83%) of the 167 patients, with a median dose of 5000 cGy (range 600 to 6500 cGy). Multivariate analysis revealed that a pilocytic histology was the most significant prognostic variable associated with a good survival. The 5- and 10-year survival rates were, respectively, 85% and 79% for the 41 patients with pilocytic astrocytomas compared to 51% and 23% for the 126 patients with ordinary astrocytomas or mixed oligoastrocytomas. Postoperative irradiation did not appear to be associated with improved survival times in the patients with pilocytic astrocytomas; however, in the 126 patients with ordinary astrocytomas or mixed oligoastrocytomas, those who received "high-dose" radiation (greater than or equal to 5300 cGy) had significantly better survival times than those who received "low-dose" radiation (less than 5300 cGy) or surgery alone. The 5- and 10-year survival rates were, respectively, 68% and 39% for the 35 patients receiving high-dose radiation, 47% and 21% for the 67 receiving low-dose radiation, and 32% and 11% for the 19 treated with surgery alone. The survival rate was poor for the 23 patients with ordinary astrocytomas and oligoastrocytomas who underwent gross total or radical subtotal tumor removal (14 of whom were also irradiated): 52% at 5 years and 21% at 10 years, with 19 of 23 patients developing tumor progression and dying 1 to 12 years postoperatively. In contrast, all 10 patients with pilocytic astrocytomas who had gross total or radical subtotal tumor removal alone were long-term survivors, with follow-up periods of about 4 to 25 years.  相似文献   
84.
Summary A correlative light and electron microscopic investigation was undertaken to determine the morphology and distribution of catecholamine (CA)-containing axon terminals in the hypoglossal nucleus (XII) of the rat. This was accomplished immunocytochemically with antibody to tyrosine hydroxylase (TH). The major findings in this study were the following: 1) Immunoreactive profiles were found throughout XII and included unmyelinated axons, varicosities, axon terminals and dendrites; 2) Nonsynaptic immunoreactive profiles (preterminal axons, varicosities) were more frequently observed (55.2%) than synaptic profiles (43.5%); 3) CA-containing axon terminals ending on dendrites were more numerous (71.8%) than those synapsing on somata (25.4%) or nonlabeled axon terminals (2.7%); 4) The morphology of labeled axon terminals was variable. Axodendritic terminals typically contained numerous small, round agranular vesicles, a few large dense-core vesicles and were associated with either a symmetric or no synaptic specialization, axosomatic terminals were often associated with a presynaptic membrane thickening or a symmetric synaptic specialization and contained small, round and a few elliptical-shaped vesicles, while axoaxonic synapses formed asymmetric postsynaptic specializations; and 5) CA-positive dendritic processes were identified in XII. These findings confirm the CA innervation of XII, and suggest a complex, multifunctional role for CA in controlling oro-lingual motor behavior.  相似文献   
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87.
Erythrocyte transketolase activation by thiamin diphosphate has been studied in elderly patients with moderate or severe chronic dementia, acute alcoholic admissions and chronic alcoholics with evidence of brain damage, mostly of the Wernicke-Korsakoff type. Significantly more patients in each group than controls showed abnormal activation of transketolase, not only by 0.3 mM thiamin diphosphate (TDP) but also in further activation by increase to 3 mM. This indicated the presence in a proportion of the alcoholic and the demented patients of an abnormal enzyme variant, similar to that previously found in vitro. The modified transketolase activation test may warn not only of marginal thiamin deficiency but also independently, of susceptibility to brain damage in patients at risk.  相似文献   
88.
Slick signaling     
Shaw AS 《Nature immunology》2002,3(11):1058-1059
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89.
Advanced glycation end products (AGEs), the final products of nonenzymatic glycation and oxidation of proteins, are found in the plasma and accumulate in the tissues during aging and at an accelerated rate in diabetes. A novel integral membrane protein, termed receptor for AGE (RAGE), forms a central part of the cell surface binding site for AGEs. Using monospecific, polyclonal antibody raised to human recombinant and bovine RAGE, immunostaining of bovine tissues showed RAGE in the vasculature, endothelium, and smooth muscle cells and in mononuclear cells in the tissues. Consistent with these data, RAGE antigen and mRNA were identified in cultured bovine endothelium, vascular smooth muscle, and monocyte-derived macrophages. RAGE antigen was also visualized in bovine cardiac myocytes as well as in cultures of neonatal rat cardiac myocytes and in neural tissue where motor neurons, peripheral nerves, and a population of cortical neurons were positive. In situ hybridization confirmed the presence of RAGE mRNA in the tissues, and studies with rat PC12 pheochromocytes indicated that they provide a neuronal-related cell culture model for examining RAGE expression. Pathological studies of human atherosclerotic plaques showed infiltration of RAGE-expressing cells in the expanded intima. These results indicate that RAGE is present in multiple tissues and suggest the potential relevance of AGE-RAGE interactions for modulating properties of the vasculature as well as neural and cardiac function, prominent areas of involvement in diabetes and in the normal aging process.  相似文献   
90.
Polymorphisms of the dopamine receptor D4 gene DRD4, 11p15.5, have previously been associated with attention-deficit/hyperactivity disorder (ADHD) [Bobb et al., 2005; Am J Med Genet B Neuropsychiatr Genet 132:109-125; Faraone et al., 2005; Biol Psychiatry 57:1313-1323; Thapar et al., 2005; Hum Mol Genet 14 Spec No. 2:R275-R282]. As a follow up to a pilot study [see Castellanos et al., 1998; Mol Psychiatry 3:431-434] consisting of 41 probands and 56 controls which found no significant association between the DRD4 7-repeat allele in exon 3 and ADHD, a greatly expanded study sample (cases n = 166 and controls n = 282) and long term follow-up (n = 107, baseline mean age n = 9, follow-up mean age of n = 15) prompted reexamination of this gene. The DRD4 7-repeat allele was significantly more frequent in ADHD cases than controls (OR = 1.2; P = 0.028). Further, within the ADHD group, the 7-repeat allele was associated with better cognitive performance (measured by the WISC-III) (P = 0.013-0.07) as well as a trend for association with better long-term outcome. This provides further evidence of the role of the DRD4 7-repeat allele in the etiology of ADHD and suggests that this allele may be associated with a more benign form of the disorder.  相似文献   
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