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101.
Spinal congenital dermal sinus is a rare entity which results from failure of the neuroectoderm to separate from cutaneous ectoderm during the process of neurulation. This epithelium-lined tract forms a potential communication between the skin surface in the midline along the spine and the deeper tissues. We describe a case of an asymptomatic lumbosacral congenital dermal sinus in a 52-year-old man. Microsurgical excision of dermal tract was performed with no postoperative complications and with a satisfactory cosmetic result. The authors stress the importance of an early neuroradiological and neurosurgical management of the lesion. The embryogenesis of this pathological condition and the possible complications are also discussed.  相似文献   
102.
Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.  相似文献   
103.
104.
Repeated treatment with the psychostimulant amphetamine produces behavioral sensitization that may represent the neural adaptations underlying some features of psychosis and addiction in humans. In the present study we investigated the role of adenosine A(2A) receptors in psychostimulant-induced locomotor sensitization using an A(2A) receptor knockout (A(2A) KO) model. Daily treatment with amphetamine for 1 week resulted in an enhanced motor response on day 8 (by two-fold compared to that on day 1), and remained enhanced at day 24 upon rechallenge with amphetamine. By contrast, locomotor sensitization to daily amphetamine did not develop in A(2A) KO mice on day 8 or 24, and this absence was not the result of a nonspecific threshold effect. The absence of behavioral sensitization was selective for amphetamine since daily treatment with the D(1) agonist SKF81297 (2.5 mg/kg) or the D(2) agonist quinpirole (1.0 mg/kg) produced similar behavioral sensitization in both WT and A(2A) KO mice. Furthermore, coinjection of SKF81297 and quinpirole also resulted in indistinguishable locomotor sensitization in A(2A) KO and WT mice, suggesting normal D(1) and D(2) receptor responsiveness. Finally, at the cellular level A(2A) receptor inactivation abolished the increase in striatal dynorphin mRNA induced by repeated amphetamine administration. The selective absence of amphetamine-induced behavioral sensitization in A(2A) KO mice suggests a critical role of the A(2A) receptor in the development of psychostimulant-induced behavioral sensitization, and supports the pharmacological potential of A(2A) adenosinergic agents to modulate adaptive responses to repeated psychostimulant exposure.  相似文献   
105.
PURPOSE: To evaluate whether lower literacy is associated with poorer knowledge and more negative attitudes and beliefs toward colorectal cancer screening among veterans without recent colorectal cancer screening. PATIENTS AND METHODS: Three hundred seventy-seven male veterans, age 50 years and older, who had not undergone recent colorectal cancer screening, were surveyed about their knowledge, attitudes, and beliefs regarding colorectal cancer screening. Patients' literacy was assessed with the Rapid Estimate of Adult Literacy in Medicine, an individually administered screening test for reading. RESULTS: Thirty-six percent of the 377 men had an eighth grade literacy level or higher. Men with lower literacy were 3.5 times as likely not to have heard about colorectal cancer (8.8% v 2.5%; P =.006), 1.5 times as likely not to know about screening tests (58.4% v 40.9%; P =.0001), and were more likely to have negative attitudes about fecal occult blood testing (FOBT), but not about flexible sigmoidoscopy. Specifically, men with lower literacy skills were two times as likely to be worried that FOBT was messy (26.7% v 13.3%; P =.008), 1.5 times as likely to feel that FOBT was inconvenient (28.7% v 18%; P =.05), and four times as likely to state they would not use an FOBT kit even if their physician recommended it (17.9% v 4.0%; P =.02). CONCLUSION: Limited literacy may be an overlooked barrier in colorectal cancer screening among veterans.  相似文献   
106.
Prognostic value of CD40 in adult soft tissue sarcomas.   总被引:4,自引:0,他引:4  
PURPOSE: The purpose is to evaluate the expression of CD40, a membrane protein predominantly expressed on B cells, dendritic cells, and macrophages, in a series of adult soft tissue sarcomas and to test its possible prognostic value. EXPERIMENTAL DESIGN: CD40 expression was studied by immunohistochemistry. Correlations with other baseline characteristics of patients and tumors were analyzed with chi(2) test. The prognostic value was studied with univariable and multivariable analysis adjusted by age, sex, tumor size, grade, location, and distant metastases. RESULTS: Eighty-two patients, between January 1994 and May 2001, were analyzed. Membrane or cytoplasmic staining for CD40 protein was absent in 30% of the tumors but present in <10% of cells in 22 (27%), in 10% to 50% in 23 (28%), and in >50% of cells in 12 (15%) tumors. There was no correlation between CD40 expression and age, sex, size, grade, and location of the primary tumor and distant metastases. With 61 patients (74.4%) progressed and 31 (37.8%) dead, CD40 expression was a significant prognostic factor for disease-free and overall survival at univariable and multivariable analysis. Patients with tumors expressing CD40 in >50% of cells had a dramatically unfavorable prognosis with median disease-free and overall survival of 7 and 17 months, respectively, and hazard ratios of relapse and death as compared with patients with CD40-negative tumors of 2.89 (95% confidence interval: 1.26-6.60) and 6.92 (95% confidence interval: 2.18-22.0), respectively. CONCLUSIONS: These data suggest that expression of CD40 protein in >50% of cells might indicate an unfavorable prognosis in adult soft tissue sarcomas.  相似文献   
107.
108.
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation.  相似文献   
109.
Background. Studies have suggested that scans with technetium-tagged white blood cells (WBC-Tc99m) may be equal to endoscopy in the assessment of extent and activity of inflammatory bowel disease (IBD). Objective. We have retrospectively examined the accuracy of WBC-Tc99m scans in differentiating continuous from discontinuous colitis in pediatric IBD. Materials and methods. There were 207 children in the study (96 boys, 111 girls, median age 13 years). This included 29 controls – children with no gastrointestinal disease (NL) who underwent WBC-Tc99m scans for other medical problems. Scans were obtained at 30 minutes and 2–4 hours following injection. Scans were interpreted as showing continuous colitis, discontinuous colitis, or no colitis. Results. In the 77 children with active Crohn's disease (CD) of the colon, the scans revealed discontinuous uptake in 63 children and continuous uptake in 14. In the 29 children with ulcerative colitis (UC), 23 scans showed continuous uptake and 6 revealed discontinuous uptake. Two of these 6 showed focal activity near the appendix, and subclinical appendicitis could not be excluded. Another child was bleeding and the scan could have been misinterpreted as showing small- bowel inflammation. In the last three patients, skip areas were clearly identifiable. In none of these last three patients were the biopsies typical of CD (i. e., no granuloma was identified) nor was inflammation patchy. In summary, of the 106 scans showing inflammation, 6 were classified into the wrong group. Conclusion. These data show that WBC-Tc99m scanning can be useful in distinguishing discontinuous from continuous colitis. Received: 20 November 1997 Accepted: 29 May 1998  相似文献   
110.
OBJECTIVE: The objective of this study is to assess CT-guided percutaneous injection of fibrin glue for the management of cerebrospinal fluid leaks within the spine. CONCLUSION: Percutaneous CT-guided placement of fibrin glue can provide a treatment option for postoperative cerebrospinal fluid leaks, potentially allowing a major surgical procedure to be avoided. However, the complication of aseptic meningitis may occasionally result from this procedure.  相似文献   
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