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991.
Background: The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer.Methods: Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis.Results: p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P < .05), confirmed by multivariate analysis (P < .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression.Conclusions: These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes.  相似文献   
992.
Patients with non-Hodgkin’s lymphoma occasionally develop widespread invasion of peripheral nerves by tumor cells or neurolymphomatosis (NL). Clinically this usually results in asymmetrical, progressive, and painful polyneuropathy. Diagnosis rests on the identification of tumor cells in peripheral nerves. To avoid false-negative biopsy findings in patients with malignant lymphomatous infiltration of peripheral nerves it has been recommended to biopsy clinically involved nerves. We present two patients with histologically confirmed NL in whom sural the nerve biopsy finding was negative despite clinical and neurophysiological evidence of involvement of the sural nerve a. The clinical features of NL are reviewed. Some patients with neurolyphomatosis have only focal or proximal involvement of nerves, requiring the biopsy of an affected part of these nerves. Magnetic resonance imaging may be useful in identifying affected nerves. Received: 28 January 1999 Received in revised form: 7 July 1999 Accepted: 17 July 1999  相似文献   
993.
Hirayama’s disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings in nine patients with Hirayama’s disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls. In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement of the anteroposterior spinal cord diameter in each vertebral segment (C4–C7) revealed no significant differences in the degree of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama’s disease is an intrinsic motor neuron disease. Received: 15 March 1999 Received in revised form: 25 May 1999 Accepted: 1 June 1999  相似文献   
994.
We investigated the skeletal muscle voltage-gated chloride channel gene (CLCN1) in two unrelated Japanese patients with Becker's myotonia congenita. The non-myotonic parents of each patient were consanguineous. The proband of each family shares generalized myotonia, transient weakness after rest, and leg muscle hypertrophy. However, the disease severity related to the degree of myotonia differed, even in view of the response to long train nerve stimulation tests. CLCN1 gene analysis revealed a novel Ala659Val missense mutation identified to be homozygous in the more severe patient, while a novel Gln445Stop nonsense mutation was present in the other patient. Both mutations were absent in 90 Japanese normal controls. This is the first report of Japanese cases of Becker's myotonia congenita with CLCN1 gene mutations.  相似文献   
995.
Drug treatment of late-stage human African Trypanosomiasis (HAT) in which the central nervous system (CNS) is involved may be complicated by a severe post-treatment reactive encephalopathy (PTRE) which can be fatal in up to 10% of cases. In order to understand the immunopathogenesis of this complication, an experimental mouse model has been developed that mirrors many of the pathological features of the PTRE in humans, and which allows various anti-inflammatory therapeutic regimes to be evaluated. Following the development of the PTRE in this model a number of cytokines are increased within the CNS including tumour necrosis factor (TNF) alpha, interleukins 1, 4 and 6, and macrophage inflammatory protein (MIP)-1. These cytokines appear at the same time as astrocyte activation which is an early event occurring before the development of the marked meningoencephalitic inflammatory response. The immunosuppressant drug azathioprine prevents but does not reduce the severity of an established PTRE and has a minimal effect on astrocyte activation. The ornithine decarboxylase inhibitor eflornithine prevents the induction, and ameliorates the severity, of the PTRE, and also reduces the degree of astrocyte activation. The Substance P antagonist RP-67,580 ameliorates the severity of an established PTRE, and also reduces astrocyte activation, indicating an important role of SP in the generation of the inflammatory response. Continued use of this mouse model should lead to further enhancement of our understanding of the pathogenesis of the PTRE and to improved drug regimes to prevent and/or treat it.  相似文献   
996.
A 67-year-old woman developed severe sicca manifestations after initial treatment of Parkinson’s disease with an anti-cholinergic drug, which prompted us to look for the presence of Sjögren’s syndrome. The results of sialography, labial salivary gland biopsy, Rose–Bengal test as well as the presence of antinuclear antibody were consistent with the diagnosis of Sjögren’s syndrome. The sicca symptoms diminished by cessation of the anti-cholinergic drug, and the parkinsonian features were controlled by levodopa. We suggest that Sjögren’s syndrome should be considered, if patients with Parkinson’s disease complain severe xerostomia.  相似文献   
997.
对象与方法:在沂蒙山区对4个乡镇的散居高龄老人121人进行营养调查(男55,女66),年龄最高男96岁,女92岁;最低男女均为80岁。以称重法与五日询问回忆法相结合,进行四季动态的膳食调查。结果:其膳食构成以谷类(占总重量61%~71%)及蔬菜(12%~16%)为主,配有少量豆类(1.8%~4.6%)与动物性食品(6.2%~12.0%)。按中国营养学会80岁以上老人RDA计算,四季能量摄入男性达到RDA的81%~91%,女性达到75%~84%,蛋白质男性仅达到67%~75%,女性55%~67%,动物和豆类蛋白质来源不足,低于蛋白质总量的30%~50%。钙摄入量只有RDA的20%左右,锌、硒、维生素A、B1、B2、C均明显不足。三大营养素所占能量比例合理,脂肪来源以植物油为主,符合老年人营养要求。营养缺乏病检查发现有维生素不足症状,如皮肤干燥鳞皮占4.1%,口角湿白厚28.9%,舌腥红22.3%,味蕾肥大81.0%,膝反射消失12.4%等。临界高血压患病率为16.1%,高血压患病率14.3%。生化检查:血红蛋白检测114人,低于120g/L者16.7%;血糖检测116人,高于正常的占6.9%,低于正常的占47?  相似文献   
998.
OBJECTIVE: To present a patient with systemic lupus erythematosus who developed infarction and melting of the orbit secondary to her systemic disease. DESIGN: A case report. PARTICIPANT: A 61-year-old white woman with a 5-year history of systemic lupus erythematosus. METHODS: The patient presented with left orbital pain, limitation of extraocular movements, and a fistula from the ethmoid sinus to the upper eyelid. A detailed examination with computerized tomography, ultrasound, and a comprehensive medical evaluation with laboratory testing was performed. Histopathologic analysis with special stains of the orbital tissues was also performed. RESULTS: Histopathologic examination of the biopsy specimens revealed the features of an inflammatory process involving the orbit, similar to a panniculitis. These include a lymphocytic reaction with a predominance of plasma cells, vasculitis with occlusion, and thickening of the vessel walls, necrosis, and hyalinization of fat. CONCLUSION: This is a unique case in which infarction and melting of the entire orbital structures occurred in the presence of systemic lupus erythematosus. The underlying disease process is a lupus-related panniculitis. The authors stress that this is a very rare entity and that other diseases should be ruled out before entertaining this diagnosis.  相似文献   
999.
视力客观检测方法的研究   总被引:4,自引:0,他引:4  
目的研究用视觉诱发电位(visualevokedpotential,VEP)作为视力客观检测的可行性。方法对40只视力不等的患眼和50只正常眼,分别记录用不同大小方格(8°、4°、2°、1°、30、15和6)刺激时的VEP波形。结果患眼组和正常组P100振幅及潜时在统计学上有显著性差异。视力与能诱发出波形的最小方格间有明显关系:最小方格为6、15、30和1°,平均视力分别为1.13,0.62,0.18和0.07。视力与P100振幅呈正相关,与潜时呈负相关。结论用诱发出VEP波形的最小方格大小可估计患者的视力范围  相似文献   
1000.
In order to assess the consequences of a concomitant blockade of P2X-receptors and ecto-nucleotidases, effects of 13 P2-receptor antagonists were investigated on contractions of the rat vas deferens elicited by α,β-methylene ATP (α,β-MeATP) and ATP and on the removal of ATP from the incubation medium by vas deferens tissue. Increasing concentrations of all antagonists reduced and finally abolished contractions elicited by α,β-MeATP (3 μM), with IC50-values ranging from 1.1 to 100 μM. Pyridoxalphosphate-6-azophenyl-2’,4’-disulphonate (PPADS), 6-azophenyl-4-amino-5-hydroxy-naphthalene-1,3-disulphonate (NH02), 4,4’-diisothiocyanatostilbene-2,2’-disulphonate (DIDS) and uniblue A also progressively reduced and finally abolished contractions elicited by ATP (1 mM). 8,8’-[Carbonylbis(imino-3,1-phenylenecarbonyl-imino)]-bis-(1,3,5-naphthalenetrisulphonate) (NF023), sura- min, pyridoxalphosphate-6-azophenyl-2’,5’-disulphonate (iso-PPADS), trypan blue and reactive blue 19, in contrast, caused only partial blockade, by 34–43% maximally; reactive blue 2 and reactive red 2 had no effect; and 6,6’-(1,1’-biphenyl-4,4’-diylbisazo)-bis-4-amino-5-hydroxy-naphtha-lene-1,3-disulphonate (NH01) and Evans blue even enhan- ced the response to ATP. For antagonists causing full or partial inhibition, the IC50-values against ATP were close to those against α,β-MeATP. All antagonists attenuated the removal of ATP, with IC25%-values ranging from 0.8 μM to >320 μM. The results confirm the frequent combination, in one antagonist molecule, of P2-receptor blockade and blockade of ecto-nucleotidases. This dual action underlies the effect of such compounds on contractions of the vas deferens elicited by ATP which, for certain substances (e.g., suramin, reactive blue 2), can be explained by a simple model in which the antagonist simultaneously blocks the degradation of ATP and a single contraction-mediating receptor (P2X1). Several observations, however, do not conform with this model, and the existence of multiple contraction-mediating receptors for ATP or multiple, pharmacologically distinct ecto-nucleotidases has to be considered. Received: 23 October 1998 / Accepted: 11 January 1999  相似文献   
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