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排序方式: 共有744条查询结果,搜索用时 15 毫秒
1.
N R Ghatak W W Campbell R H Lippman M G Hadfield 《Journal of neuropathology and experimental neurology》1986,45(4):385-395
Morphologic study of the spinal cord of a patient with generalized motor deficits revealed changes in the anterior horns characterized by the selective loss of large motor neurons, gliosis and the abnormal accumulation of 10 nm filaments which appeared as argyrophilic spheroids in the perikarya and axons of motor neurons. The ventral roots were predominantly affected and showed a variable loss of axons. The remaining axons displayed prominent onion-bulb formations, frequent axonal sprouting and occasionally evidence of active demyelination. The coexistence of a demyelinating motor radiculopathy and anterior horn changes simulating those of amyotrophic lateral sclerosis (ALS) may contribute to our understanding of the unresolved question of whether the neuronal perikaryon or its axon is the primary target in the pathogenesis of ALS. These observations also indicate that a rigid separation of pathogenetic mechanisms into neuronopathy, axonopathy and myelinopathy may not be always possible. 相似文献
2.
Olfactory Neuroblastoma and Neuroendocrine Carcinoma of the Anterior Skull Base: Treatment Results at the M.D. Anderson Cancer Center
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John R. Austin Hazel Cebrun Mathew M. Kershisnik Adel K. El-Naggar Adam S. Garden Franco DeMonte Lawrence E. Ginsberg Scott M. Lippman Helmuth Goepfert 《Skull base》1996,6(1):1-8
Updated information on the pathologic characterization and treatment of olfactory neurobiastoma (ON) and neuroendocrine carcinoma (NEC) diseases is presented. A series of patients with ON or NEC was evaluated and retrospectively staged using the UCLA system. The parameters evaluated were symptoms, age, sex, risk factor assessment, stage of disease, treatment, and clinical outcome. The median follow-up was 3 years (range, 18 months to 23 years). The predominant therapy (63%) for ON was combined surgery and radiotherapy. Surgery alone or in combination with ancillary treatment was used in 58% of patients with NEC. For the most receat years of the study, patients with NEC have been treated successfully with combined chemotherapy and radiotherapy. Seventy percent of the patients with ON and 75% of the patients with NEC were clinically free of disease during the defined follow-up period. Surgical therapy consisting of a craniofacial resection combined with postoperative radiotherapy has resulted in good local and long-term control of ON. Our experience indicates that combined chemoradiation is an appropriate therapeutic approach for NEC. 相似文献
3.
We have identified a secreted glycoprotein with an apparent molecular weight of 39,000 that is inhibited by estrogens and stimulated by antiestrogens in the MCF-7 human breast cancer cell line. The protein was detected within 24 h of hormone treatment with inhibition occurring at concentrations as low as 10(-11) M estradiol and stimulation occurring with antiestrogens. When phenol red, which has been found to have estrogenic activity, is removed from the tissue culture medium, no inhibition of cell growth or induction of the Mr 39,000 protein is seen with antiestrogens. A 6-fold decrease in the amount secreted in the presence of estrogens is seen under these conditions. The induction was specific in that growth inhibition by several other means did not induce expression of the Mr 39,000 protein. The Mr 39,000 protein has been identified as a glycoprotein complex that can be resolved into four polypeptides with two major components that migrate in the pH range of 5.5 to 6.3 by two-dimensional gel electrophoresis. This protein is the first evidence that estrogens inhibit a specific protein and it may prove useful as a marker of antiestrogen-induced growth arrest in breast cancer. 相似文献
4.
The role of report (recall) bias in case-control studies of possible reproductive hazards was investigated in a study of women who gave birth at the Royal Victoria Hospital, Montreal from September 1983 to May 1985. Women were questioned twice (early in pregnancy; after delivery) about exposures that might influence pregnancy outcome. The two sets of responses of case mothers, control mothers, and mothers of infants of intermediate health status were then compared. Similar inconsistencies in the reporting of 39 exposure variables were common in all three groups, with postdelivery deletion of previous reports more frequent than addition of new information. Changes in reporting were not associated with pregnancy outcome, maternal concern about the baby or maternal sociodemographic characteristics. Odds ratios of exposure estimated from the two sets of data did not differ importantly. Moreover, there was no postdelivery trend to increases, or decreases, in the estimates of the odds ratios. The data do not provide evidence of biased reporting of exposures. 相似文献
5.
Near-maximal anxiety by subjective and behavioral criteria was evoked and terminated in phobic patients by initiation and termination of rapid live confrontation ("flooding in vivo") with the specific stimulus that each avoided, at a time approximating the crest of the circadian cycle of adrenal cortical function. The procedure was associated with moderate, but not marked, elevations of plasma cortisol above control levels in some, but not all, subjects. Differences in anxiety levels as self-rated by the patients did not account for differences in cortisol response. The findings should stimulate further reevaluation of the hypothesis that affective arousal is the key psychological determinant of adrenal cortical function. Dissociation between subjective-behavioral arousal and plasma cortisol during flooding may be a manifestation of what behavior therapists call "desynchrony of fear." 相似文献
6.
Erik W. Thompson Jeffrey Torri Marybeth Sabol Connie L. Sommers Stephen Byers Eva M. Valverius George R. Martin Marc E. Lippman Martha R. Stampfer Robert B. Dickson 《Clinical & experimental metastasis》1994,12(3):181-194
Expression of the intermediate filament protein vimentin, and loss of the cellular adhesion protein uvomorulin (E-cadherin) have been associated with increased invasiveness of established human breast cancer cell linesin vitro andin vivo. In the current study, we have further examined these relationships in oncogenically transformed human mammary epithelial cells. A normal human mammary epithelial strain, termed 184, was previously immortalized with benzo[a]pyrene, and two distinct sublines were derived (A1N4 and 184B5). These sublines were infected with retroviral vectors containing a single or two oncogenes of the nuclear, cytoplasmic, and plasma membrane-associated type (v-ras
H, v-ras
Ki, v -mos, SV40T and c -myc). All infectants have been previously shown to exhibit some aspects of phenotypic transformation. In the current study, cellular invasiveness was determinedin vitro using Matrigel, a reconstituted basement membrane extract. Lineage-specific differences were observed with respect to low constitutive invasiveness and invasive changes after infection withras, despite similarras-induced transformation of each line. Major effects on cellular invasiveness were observed after infection of the cells with two different oncogenes (v-ras
H + SV40T and v -ras
H + v -mos). In contrast, the effects of single oncogenes were only modest or negligible. All oncogenic infectants demonstrated increased attachment to laminin, but altered secretion of the 72 kDa and 92 kDa gelatinases was not associated with any aspect of malignant progression. Each of the two highly invasive double oncogene transformants were vimentinpositive and uvomorulin-negative, a phenotype indicative of the epithelial-mesenchymal transition (EMT) previously associated with invasiveness of established human breast cancer cell lines. Weakly invasive untransformed mammary epithelial cells in this study were positive for both vimentin and uvomorulin, suggesting that uvomorulin may over-ride the otherwise vimentin-associated invasiveness. 相似文献
7.
C J Allegra B A Chabner P W Sholar C Bagley J C Drake M E Lippman 《NCI monographs : a publication of the National Cancer Institute》1987,(5):199-202
The active metabolite of FUra, 5-fluorodeoxyuridine monophosphate (5-FdUMP), requires the presence of reduced folates to form a covalent ternary complex with the target enzyme thymidylate synthase (TS). In vitro and in vivo studies have demonstrated a potentiation of the cytotoxic effects of FUra when combined with the reduced folate, leucovorin. We have applied this concept to the treatment of metastatic breast cancer in a phase II trial, as recent clinical studies on patients with colorectal carcinoma have suggested an enhanced efficacy for the combination of FUra plus leucovorin. Patients entered on the present study are undergoing treatment with a 5-day daily regimen of leucovorin (500 mg/m2, iv) followed by FUra (375 mg/m2, iv). Toxicity and response data are currently being collected on patients who have failed "standard" combination regimens that included FUra. In patients with accessible tumor, serial biopsies are being obtained during treatment with the combination of FUra and leucovorin and during therapy with FUra alone to assess the degree of 5-FdUMP binding to the target enzyme, TS, in the presence and absence of exogenously administered leucovorin. Preliminary results from the biochemical studies suggest an enhanced saturation of TS by the fluorinated pyrimidine when administered with leucovorin. 相似文献
8.
Marc E. Lippman Robert B. Dickson Susan Bates Cornelius Knabbe Karen Huff Sandra Swain Mary McManaway Diane Bronzert Attan Kasid Edward P. Gelmann 《Breast cancer research and treatment》1986,7(2):59-70
Summary We consider the hypothesis that estrogen control of hormone dependent breast cancer is mediated by autocrine and paracrine growth factors secreted by the breast cancer cells themselves. Though we show direct, unmediated effects of estrogen on specific cell functions, we also provide evidence that human breast cancer cells secrete a collection of growth factors (IGF-I, TGF, TGF, a PDGF-like competency factor, and at least one new epithelial colony stimulating factor). Some of these are estrogen-regulated in hormone dependent cells, and are constitutively increased in cells which acquire independence either spontaneously or byras transfection. Collectively, the secreted growth factors are capable of promoting tumor formation by MCF-7 cells in nude mice, though not to the same extent as estrogens. There would seem to be potential for clinical intervention in the autocrine and paracrine control of breast cancer cells, including some cells which are no longer dependent on estrogens. 相似文献
9.
10.