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151.
The microvascular frontal-subcortical syndrome of aging 总被引:11,自引:0,他引:11
Many features of aging suggest dysfunction in both frontal and subcortical regions. Connections between the two areas form a series of pathways that critically influence various aspects of cognition, motor control, affect, and as recently discovered, normal urinary function. Age-related changes in the structure and integrity of these circuits may be associated with cognitive impairment, mood disorders, loss of balance, falls, and urinary dysfunction. In addition, cardiovascular risk factors in elderly people are associated with the development of cerebral microangiopathic changes in both the periventricular white matter and basal ganglia. These lesions are common, usually unsuspected, and were previously believed to be clinically innocuous. However, increasing evidence supports a role for these lesions as a cause for both dysfunction in frontal-subcortical systems, and many clinical features of aging that account for substantial disability. Because this form of cerebrovascular disease is potentially preventable, interventions that address risk factors for the development of cerebral microangiopathy may go a long way in preventing disability for the next generation of elderly persons. 相似文献
152.
Risk of localized and widespread endometrial cancer in relation to recent and discontinued use of conjugated estrogens 总被引:13,自引:0,他引:13
S Shapiro J P Kelly L Rosenberg D W Kaufman S P Helmrich N B Rosenshein J L Lewis R C Knapp P D Stolley D Schottenfeld 《The New England journal of medicine》1985,313(16):969-972
In a case-control study of the risk of adenocarcinoma of the endometrium in relation to conjugated-estrogen use, we found that 31 per cent of 425 women with endometrial cancer and 15 per cent of 792 controls reported having used conjugated estrogens; the rate-ratio estimate was 3.5 with a 95 per cent confidence interval of 2.6 to 4.7. For use that lasted at least one year, the rate-ratio estimate for Stage I or II cancer was 5.2 (95 per cent confidence interval, 3.7 to 7.2), and for Stages III and IV combined it was 3.1 (1.5 to 6.4). Among women who had used estrogen for at least one year and then discontinued it, the risk of endometrial cancer remained significantly elevated even after estrogen-free intervals of over 10 years. The findings suggest that long-term use of conjugated estrogen increases the risk of both localized and widespread endometrial cancer. The data also suggest that women who have taken conjugated estrogen for one or more years remain at increased risk for at least 10 years after they discontinue use. Such women should be considered for long-term gynecologic surveillance. 相似文献
153.
S F Cramer S N Rosenthal A J Swinburne C L Lewis 《Archives of pathology & laboratory medicine》1989,113(11):1236-1238
This report presents two cancer cases with protracted courses in which diagnostic immunohistochemistry for thyroglobulin and/or calcitonin was performed several years after the original light microscopic interpretation. In both cases, diagnostic immunohistochemistry suggested significant changes in tumor classification. In light of current controversies and interpretive problems in this area, confirmatory tests for serum calcitonin and serum thyroglobulin and scans for iodine 131 uptake were performed. These confirmed the immunohistochemical evidence, and led to major changes in patient management. Several similar cases were found in the literature. In cancer cases with a protracted course, but with atypical or discordant clinical and/or pathologic features, diagnostic immunohistochemistry for thyroid markers may merit consideration because of the potential for meaningful changes in clinical management. 相似文献
154.
'Psychogenic': a word and its mutations 总被引:3,自引:0,他引:3
A Lewis 《Psychological medicine》1972,2(3):209-215
155.
156.
Juvenile galactosialidosis in a white male: a new variant 总被引:2,自引:0,他引:2
D Chitayat D A Applegarth J Lewis J E Dimmick A Q McCormick J G Hall 《American journal of medical genetics》1988,31(4):887-901
We describe a 19-year-old white male with juvenile galactosialidosis. He presented with hip arthralgia and was found to have facial "coarseness," corneal clouding, mitral and aortic insufficiency, and hepatosplenomegaly. Ultrastructural studies of skin biopsy and peripheral blood lymphocytes showed membrane-bound inclusions containing sparse fibrillogranular material. Biochemical analysis showed elevated urinary sialyloligosaccharides and no free sialic acid. Fibroblast enzyme analysis showed low activities of both alpha-neuraminidase and beta-galactosidase. To date, most patients with juvenile galactosialidosis have been Japanese. However, unlike those patients, our patient did not have macular cherry-red spots, neurologic abnormalities, or mental retardation. We speculate that this young man represents a new subtype of juvenile galactosialidosis with a potentially different molecular defect from that of the Japanese variant. 相似文献
157.
Summary of complementation groups of UV-sensitive CHO cell mutants isolated by large-scale screening 总被引:7,自引:0,他引:7
Busch David; Greiner Carol; Lewis Kathy; Ford Ruth; Adair Gerald; Thompson Larry 《Mutagenesis》1989,4(5):349-354
A summary is given for the lineage and complementation groupassignments of 153 UV-sensitive mutants of the CHO AA8 cellline. The distribution of mutants among six complementationgroups was highly non-random, with the great majority of theisolates belonging to groups 1 and 2. This asymmetry is consistentwith the known hemizygosity of these two linked loci in CHOcells. The relative numbers of mutants induced in group 2 wasfound to depend greatly on the type of mutagen used. Mutagenesiswith UV radiation, ethyl methanesulfonate (EMS), N-methyl-N'-nitro-N-nitroso-guanidine and 7-bromomethylbenz[a]anthraceneproduced high frequencies of group 2 mutants. In contrast, ICR170and ICR191, which are thought to produce mostly frameshift mutations,yielded very few mutants in group 2. These results are of particularimportance in light of the recent finding that the human ERCC2gene, which corrects group 2 mutants, has very strong homologywith the yeast gene RAD3. RAD3 is an essential gene for viabilityin yeast, and the low recovery of group 2 mutants using theframeshift agents strongly suggests that frameshift mutationstend to be lethal in the hamster ERCC2 locus. Several mutagen-sensitivedouble mutants were isolated in two-step selections from EMS-,mitomycin C- or UV-sensitive parental cells, including the lineUVU1, the first mammalian line with two mutations that affectUV sensitivity. The first mutation inactivated excision repair,and the second mutation appears to have affected some otherrecovery process. UVU1 should be useful for studying recoveryprocesses that are separate from nucleotide excision repair.
1To whom correspondence should be addressed 相似文献
158.
G. A. Lamaris B. Esmaeli G. Chamilos A. Desai R. F. Chemaly I. I. Raad A. Safdar R. E. Lewis D. P. Kontoyiannis 《European journal of clinical microbiology & infectious diseases》2008,27(5):343-347
Few data exist on the etiology, presentation, prognosis, and management of fungal endophthalmitis (FE) in cancer patients.
FE cases were identified by reviewing the ophthalmology reports and microbiology cultures of patients at The University of
Texas M. D. Anderson Cancer Center. We retrospectively reviewed the medical records and obtained information related to malignancy,
fungal infection and its management, visual outcome, and mortality. We compared FE caused by Candida spp. (CE) to FE caused by molds (ME). Of the 102 cancer patients with a fungal infection for whom an ophthalmology consult
was requested, 23 met the criteria for definite (N = 6) or probable (N = 17) FE (8 with CE, 15 with ME). All of the patients with ME had hematologic malignancies, whereas half of the patients
with CE had solid tumor (P = .008). Only patients with CE had a history of surgery within 30 days of FE diagnosis (38%, P = .03). Fungal pneumonia [17 (74%)] and disseminated infection [14, (61%)] were common. The most common presenting symptoms
were decreased vision [16 (70%)] and ocular pain [14 (61%)]. All treated patients received systemic antifungals (combination
therapy in 72% of the cases). Seven patients (30%) underwent vitrectomy. Only one patient received intraocular injection of
amphotericin B along with systemic antifungals. Four-week mortality was high [13 (57%)], especially in ME (73%, P = .04). Among the eight surviving patients where visual acuity could be assessed, visual outcome improved or remained stable
in five (63%). FE in cancer patients occurs in the setting of severe, frequently disseminated opportunistic mycoses, is caused
predominantly by hyalohyphomycetes, and is a marker for high 4-week mortality. 相似文献
159.
Regional cerebral blood flow (rCBF) during a word fluency task was compared in twenty-five male, right-handed, medicated schizophrenic patients and twenty-five age-matched male, right-handed healthy volunteers, using 99mtechnetium-HMPAO multidetector single-photon emission tomography. Increased rCBF in caudate and thalamus was found in patients, probably secondary to neuroleptic medication. Patients showed decreased rCBF in left frontal cortical regions and increased rCBF in left posterior cortical regions, compared to controls. Patterns of left-sided frontal rCBF dominance in controls were reversed in patients, as were normal patterns of right-sided parietal rCBF dominance. Negative symptom score correlated inversely with mesial frontal rCBF, particularly on the left. 相似文献
160.
Angiogenic and lymphangiogenic microvessel density in breast carcinoma: correlation with clinicopathologic parameters and VEGF-family gene expression. 总被引:22,自引:0,他引:22
William W L Choi Melinda M Lewis Diane Lawson Qiqin Yin-Goen George G Birdsong George A Cotsonis Cynthia Cohen Andrew N Young 《Modern pathology》2005,18(1):143-152
Angiogenesis and lymphangiogenesis are essential for breast cancer progression and are regulated by vascular endothelial growth factors (VEGF). To determine clinical and molecular correlates of these processes, we measured blood and lymphatic vascular microvessel density in 29 invasive carcinomas (22 ductal, six lobular, one papillary), using the vascular marker CD31 and the novel lymphatic marker D2-40. Microvessel density was assessed microscopically and by image cytometry, and was compared with tumor histology, grade, stage, lymph node metastasis, hormone receptors, HER2/neu status, and expression of VEGF, VEGF-C and VEGF-D by immunohistochemistry or quantitative RT-PCR. Strong correlation was observed between visual and image cytometric microvessel density using D2-40 but not CD31 (P=0.016 and 0.1521, respectively). Image cytometric CD31 microvessel density correlated with tumor size, grade, stage and lymph node metastasis (P=0.0001, 0.0107, 0.0035 and 0.0395, respectively). D2-40 microvessel density correlated with tumor stage (P=0.0123 by image cytometry) and lymph node metastasis (P=0.0558 by microscopy). Immunohistochemical VEGF signal in peritumoral blood vessels correlated with image cytometric CD31 and D2-40 microvessel density (P=0.022 and 0.0012, respectively), consistent with the role of VEGF in blood and lymphatic vascular growth. Intratumoral VEGF-C and VEGF-D expression by quantitative RT-PCR correlated with D2-40 (P=0.0291 by image cytometry) but not with CD31 microvessel density, which could suggest a selective role of VEGF-C and VEGF-D in lymphangiogenesis. CD31 and D2-40 microvessel density correlated significantly with several prognostic factors, including lymph node metastasis. Thus, measurements of angiogenesis and lymphangiogenesis may have utility for breast cancer pathology, particularly for estimation of metastatic risk. 相似文献