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31.
Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites–the esophagus, the pancreas, and the prostate gland–there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers.  相似文献   
32.
Background :
The aim of this study was to examine nuclear p53 overexpression in transitional cell carcinoma of the bladder, adenocarcinoma of the prostate, and renal cell carcinoma.
Methods :
Forty-four pathologic specimens from 39 bladder cancer patients, 41 prostatic adenocarcinoma, and 39 renal cell carcinoma specimens were analyzed immunohistochemically with D07 monoclonal antibody to detect the expression of the mutant p53 gene. Overexpression was said to occur when the number of positively-stained tumor nuclei were≥ 10% in each specimen. p53 overexpression was correlated with the clinical and histopathological features of these cancers.
Results :
Nuclear p53 overexpression occurred in 18.2% of transitional cell bladder cancer specimens, 12.2% of prostate cancer specimens, and 17.9% of renal cell cancer specimens. Statistical analyses showed that grade, vascular invasion, and necrosis in bladder cancer, a high Gleason score in prostate cancer, and the 1-year mortality rate in renal cancer were significantly related with p53 nuclear overexpression (P<0.05).
Conclusion :
Using the D07 monoclonal antibody, nuclear p53 overexpression is relatively uncommon in urologic malignancies, and moderately correlates with several histopathological and clinical features of urologic malignancies.  相似文献   
33.
Background :
The BTA test is a latex agglutination assay for the qualitative detection in the urine of analytes that are associated with bladder tumor. We compared the results of the BTA test with those of voided urine cytology (VUC) in patients with bladder cancer.
Methods :
A multicenter trial was performed at 6 institutions. A total of 132 patients with histologically diagnosed bladder cancer were enrolled. Urine samples were split for BTA and VUC testing.
Results :
The sensitivities of the BTA test and VUC were 57.6% and 37.9%, respectively; this difference was significant ( P < 0.001). The BTA test had much higher sensitivity for small, solitary, superficial tumors than did VUC.
Conclusion :
The BTA test is simple to perform, gives rapid results, and is far more sensitive than VUC for detection of bladder cancer. The BTA test has the potential to become an additional tool for detecting bladder cancer.  相似文献   
34.
目的 探讨原发性十二指肠肿瘤 (PTD)的诊断和治疗。方法 回顾性分析我院 1995 2 0 0 3年间 4 3例PTD的临床资料。结果 十二指肠镜确诊率为 85 .7% ,B超检查的阳性率为 5 5 .6 % ,CT检查阳性率为 80 % ,肿瘤位于十二指肠降段 (乳头部或其对侧 ) 35例 ,占 81.4 % ,2例平滑肌瘤切除术后存活 5年以上 ,1例乳头部腺瘤行肿瘤局部切除术后半年出现黄疸 ,病因不详。 4例间质瘤均健在且生存 16 2 1个月 ,36例原发性十二指肠恶性肿瘤中胰头十二指肠切除 18例 ,节段切除 1例 ,手术切除率为 5 1.2 %。结论 B超、CT、纤维十二指肠镜检查是诊断PTD的主要手段。手术切除是最基本有效的治疗方法。对于良性肿瘤可行局部肿瘤切除、十二指肠节段切除或经内镜切除。对于恶性肿瘤 ,胰十二指肠切除术是首选术式。  相似文献   
35.
①目的 探讨肺癌中血管内皮生长因子受体Flt1、KDR的表达与其转移及预后的关系。②方法 应用免疫组织化学PowerVisionTM PV90 0 0法 ,测定 75例肺癌标本中Flt1、KDR的表达。③结果 肺癌组织中Flt1、KDR的表达较为广泛 ,主要位于肿瘤细胞胞浆及胞膜上 ,纤维母细胞和血管内皮细胞胞浆中亦有表达。Flt1、KDR在肿瘤细胞中的阳性率均显著高于在间质纤维母细胞中的表达 (χ2 =6 .0 7、5 .88,P <0 .0 5 )。肿瘤细胞及纤维母细胞中该两种受体的阳性率在不同年龄、不同性别及不同病理类型、不同病理分级之间差异均无显著性 (χ2 =0 .0 1~4 .84 ,P >0 .0 5 ;P =0 .2 9~ 0 .79)。肿瘤细胞中Flt1、KDR的阳性表达率在 3组不同大小的肿瘤间差异均有显著性(χ2 =1 0 .35、7.2 9,P <0 .0 5 ) ,而纤维母细胞中差异均无显著性 (χ2 =2 .86、2 .5 6 ,P >0 .0 5 ) ;肿瘤细胞及纤维母细胞中Flt1、KDR的阳性率在淋巴结有、无转移两组间的差异均有显著性 (χ2 =4 .72~ 9.32 ,P <0 .0 5 ) ,在 3组不同术后生存时间病人间亦均有显著性差异 (χ2 =8.81~ 1 9.1 9,P <0 .0 5 )。肿瘤细胞中Flt1、KDR的表达呈极显著性正相关 (r =0 .4 4 ,P <0 .0 1 )。④结论 肺癌的生长主要依赖自分泌机制 ,联合检测Flt1、KDR可能对肺癌转移  相似文献   
36.
ΔNp63蛋白在膀胱移行上皮癌中的表达及其临床意义   总被引:3,自引:1,他引:2  
目的 :探讨 p5 3基因家族新成员截短型p6 3(△Np6 3)在膀胱癌组织中的表达及其意义。 方法 :采用免疫组织化学SP法检测 4 0例膀胱移行上皮癌 (TCC)、6例膀胱内翻性乳头状瘤和 8例正常膀胱移行上皮中△Np6 3的表达 ,并分析△Np6 3表达与膀胱癌病理类型、临床分期的关系。 结果 :正常膀胱移行上皮、膀胱内翻性乳头状瘤、TCC中△Np6 3的阳性表达率分别为 37.5 % (3/ 8)、6 6 .7% (4/ 6 )、10 0 % (40 / 4 0 ) ,组间差异有统计学意义 (P <0 .0 1)。TCCG3 级与G2 级△Np6 3的强阳性、中度阳性表达率显著高于G1级 (P <0 .0 1)。Ta~T1期以△Np6 3弱阳性为主 (6 6 .7% ) ,随TCC浸润程度的增加 ,△Np6 3染色强度逐渐增强。T2 期△Np6 3强阳性表达率为 35 .3% ,T3 ~T4期增至 6 3.6 %。结论 :△Np6 3在TCC中高表达 ,与TCC病理分级、临床分期密切相关 ;△Np6 3可能参与TCC的发生、发展 ,是评估TCC预后的潜在因素之一。  相似文献   
37.
皮肤交界性平滑肌瘤的复发与恶性转化   总被引:3,自引:0,他引:3  
目的探讨皮肤交界性平滑肌瘤的复发与恶性转化。方法复习2例皮肤交界性平滑肌瘤及其复发恶性转化的临床病理特征、免疫组化表型及相关文献。结果2例病变位于下肢和额部,肉瘤组织平滑肌标记阳性。结论少数病理诊断为皮肤平滑肌瘤的病例,虽然浅表且组织形态良性,但其生物学恶性潜能尚不能确定,部分病例复发后可转变为典型的平滑肌肉瘤。  相似文献   
38.
目的 :探讨白细胞介素 2 (IL 2 )对垂体瘤细胞系RC 4B/C细胞ACTH分泌的调控作用及其影响因素 .方法 :以放射免疫方法测定培养的垂体瘤细胞系RC 4B/C细胞的培养液中的ACTH浓度 .结果 :IL 2 (1× 10 4~ 5× 10 5U·L-1)促进RC 4B/C细胞分泌ACTH ;蛋白激酶A的抑制剂H 9(1μmol·L-1)和酪氨酸蛋白激酶的抑制剂tyrphostin2 3 (1μmol·L-1)均可显著性抑制IL 2的促ACTH分泌作用 .结论 :IL 2可促进RC 4B/C细胞分泌ACTH ,该作用与蛋白激酶A和酪氨酸蛋白激酶信号转导途径紧密相关  相似文献   
39.
Surgical Treatment of Intractable Seizures Due to Hypothalamic Hamartoma   总被引:16,自引:7,他引:9  
Summary: A 6.5-year-old boy developed seizures at age 2.8 years consisting of episodes of unconsciousness and laughing attacks. By age 6 years, multiple seizure types, including generalized tonic-clonic (GTC), complex partial (CPS) and akinetic seizures, and drop attacks were occurring several times daily. EEG showed multifocal epileptic discharges. Antiepileptic drugs (AEDs) did not control the seizures. With progression of the epilepsy, cognitive deterioration developed. There were no manifestations of precocious puberty. Neuroimaging disclosed a suprasellar mass in continuity with the hypothalamus, and a diagnosis of hypothalamic hamartoma was made. After surgical resection of the hamartoma, the seizures were completely alleviated, and the epileptic EEG discharges disappeared. Improvement of mental function was also noted.  相似文献   
40.
应用不经胸食管钝性剥离拔脱术治疗26例咽下癌与高位食管癌,效果良好,术后5例发生开发症,其中颈部吻合口痿3例,暂时性咳呛1例,腹部切口局限裂开1例。手术死亡率7.6%(2/26)。介绍了手术方法,对不经胸施术、胃体缝缩、颈部食管胃Gambee氏吻合法应用进行了讨论。  相似文献   
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