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排序方式: 共有9825条查询结果,搜索用时 184 毫秒
991.
ABSTRACT: Since the dermatologist may often see the cutaneous manifestations of viral hepatitis, it is important to review the current treatment and prevention regimens of each type of hepatitis. Viral hepatitis is treatable, and the goal of new antiviral and immunomodulatory agents is increased life expectancy, decreased risk of cirrhosis and hepatocellular carcinoma, and improvement in the dermatologic manifestations, all which occur once the viral burden is eradicated or significantly reduced. 相似文献
992.
The papillary-cystic neoplasm of the pancreas. An increasingly recognized clinicopathologic entity 总被引:3,自引:0,他引:3
J A Sanchez K D Newman M R Eichelberger R J Nauta 《Archives of surgery (Chicago, Ill. : 1960)》1990,125(11):1502-1505
The clinical course of the papillary-cystic neoplasm of the pancreas is contrasted with that of the pancreatic ductal adenocarcinoma. The former occurs predominantly in young women, has a low malignant potential, and is highly curable with surgical treatment. Three cases are reported that illustrate the typical clinical features and the indolent nature of the tumor. One case was discovered after blunt abdominal trauma resulted in rupture of the tumor and hemoperitoneum. All cases were treated by pancreatic resection with preservation of the spleen, an important consideration in younger patients. All patients were free of disease at long-term follow-up. Increasing awareness of this tumor has resulted in the reclassification of several tumors and should lead to better recognition by surgeons caring for patients with pancreatic diseases. 相似文献
993.
Paul W. Brazis MD Neil R. Graff-Radford MD Nancy J. Newman MD Andrew G. Lee MD 《American journal of ophthalmology》1998,126(6):850-851
PURPOSE: To alert ophthalmologists to the use of Ishihara color plates in the detection of simultanagnosia.METHODS: We examined seven patients referred for impaired vision. Evaluation included color plate testing with Ishihara color plates.RESULTS: All seven patients had simultanagnosia, with marked difficulty in identifying the numbers in Ishihara color plates despite adequate visual acuity and the ability to name all of the colors in the plates correctly. One of these patients was referred with the diagnosis of a cone dystrophy because of her poor performance on the Ishihara test. All of the patients had bilateral occipitoparietal damage or atrophy on magnetic resonance imaging.CONCLUSIONS: Ophthalmologists must be aware that a poor performance with Ishihara plates may not be attributable to an impairment of color vision but rather to occipitoparietal brain damage associated with simultanagnosia. 相似文献
994.
C F Winkler N R Dunnick J L Eddy R D Newman D C Ihde 《Medical and pediatric oncology》1986,14(1):20-25
Computed tomography of the abdomen and pelvis has been used to stage early prostatic cancer. We investigated its value in monitoring tumor response in more advanced disease. Serial computed tomography of the abdomen and pelvis was obtained along with multiple other staging tests prior to treatment and at 3- to 4-month intervals thereafter in 32 patients with stage D2 tumor treated initially with combination chemotherapy and with hormones at progression. Pretreatment lymphography with follow-up abdominal films was also performed. Initial computed tomography of the abdomen and pelvis showed evidence of node metastases in 35% of patients while lymphography was positive in 54%. Among 19 patients with tumor response and 25 with progression, the results of treatment were objectively documented by improvement or worsening, respectively, in a mean of 5.1 and 5.0 other staging tests, exclusive of computed tomography. Computed tomography of the abdomen and pelvis improved in 85% of responding patients examined. Progression was confirmed by worsening of computed tomography in 32%. Although lymphography was often abnormal prior to treatment, in our hands it was not useful in serial monitoring of tumor status. We conclude that serial computed tomography of the abdomen and pelvis, when initially positive, is a useful test to document objectively tumor response and progression in disseminated prostatic cancer. 相似文献
995.
Prolonged increases in plasma glucocorticoids can exacerbate neurodegeneration. In rats, these neurodegenerative effects can be reduced by dehydroepiandrosterone (DHEA), an androgen precursor with anti-glucocorticoid actions. In song sparrows, season and acute restraint stress affect circulating levels of corticosterone and DHEA, and the effects of stress differ in plasma collected from the brachial and jugular veins. Jugular plasma is an indirect index of the neural steroidal milieu. Here, we directly measured corticosterone and DHEA in several brain regions and jugular plasma, and examined the effects of season and acute restraint stress (30 min) ( n = 571 samples). Corticosterone levels were up to 10× lower in brain than in jugular plasma. In contrast, DHEA levels were up to 5× higher in brain than in jugular plasma and were highest in the hippocampus. Corticosterone and DHEA concentrations were strongly seasonally regulated in plasma but, surprisingly, not seasonally regulated in brain. Acute stress increased corticosterone levels in plasma and brain, except during the molt, when stress unexpectedly decreased corticosterone levels in the hippocampus. Acute stress increased DHEA levels in plasma during the molt but had no effects on DHEA levels in brain. This is the first study to measure (i) corticosterone or DHEA levels in the brain of adult songbirds and (ii) seasonal changes in corticosterone or DHEA levels in the brain of any species. These results highlight several critical differences between systemic and local steroid concentrations and the difficulty of using circulating steroid levels to infer local steroid levels within the brain. 相似文献
996.
Isolated acquired unilateral horizontal gaze paresis from a putative lesion of the abducens nucleus.
Neil R Miller Valérie Biousse Thomas Hwang Saurabh Patel Nancy J Newman David S Zee 《Journal of neuro-ophthalmology》2002,22(3):204-207
In three patients, acute horizontal gaze pareses developed that could not be overcome with the oculocephalic maneuver, indicating a putative lesion of the ipsilateral abducens nerve nucleus. None of the patients had a facial nerve paresis or evidence of a trigeminal sensory neuropathy. Although most lesions that affect the abducens nerve nucleus also damage the ipsilateral fasciculus of the facial nerve, small lesions in this region can produce an isolated horizontal gaze paresis. 相似文献
997.
998.
Leukotriene B4, an autacoid metabolite of arachidonic acid produced by polymorphonuclear neutrophils, induces chemokinesis, chemotaxis, and adhesion of these cells at sites of inflammation. Because neutrophil infiltration is a self-limited process, we hypothesized that oxidized lipid products of neutrophil-damaged tissue might inhibit leukotriene B4 biosynthesis, thereby preventing additional neutrophil infiltration and limiting peroxidative tissue damage. Erythrocyte ghosts exposed to a hydrogen peroxide-generating system served as a model of peroxidized tissue in inflammation and inhibited neutrophil leukotriene B4 production by 50% compared with unoxidized ghosts. Organic peroxides, including tert-butylhydroperoxide, peracetic acid, and linoleic hydroperoxide, resembling the product(s) of tissue membrane peroxidation in lipid solubility and catalase resistance, inhibited leukotriene B4 biosynthesis in a dose-dependent manner (50% inhibitory concentration of 3.9 microM compared to 530 microM for H2O2). Biosynthetic steps prior to the 5-lipoxygenase did not appear to be the site of inhibition. Likewise, the step after the 5-lipoxygenase, the leukotriene A4 hydrolase, was not primarily involved. Thus a possible mechanism for controlling the influx of neutrophils and their oxidative damage during inflammation may be inhibition of the 5-lipoxygenase by catalase-resistant lipid peroxides released by tissue membranes. 相似文献
999.
1000.