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21.
Cervical smears were reviewed from patients in whom a cytological abnormality was followed, after an interval without interference, either by regression to `negative' or else by progression to invasive carcinoma. Twenty-eight cases were from a previously analysed series with positive smears and an interval of at least two years before investigation, resulting from refusal or failure to trace. Slides were also reviewed from 25 cases in which `positive' smears had regressed to negative without escaping from surveillance, and from 10 patients subsequently developing invasive carcinoma whose previous slides, taken several years earlier, showed abnormalities on review. None of these 63 patients had any biopsy or other surgical procedure to the cervix between the initial smear and the outcome.

Slides showing `superficial cell dyskaryosis' and/or well-differentiated `parabasal cell dyskaryosis' were found only among the groups with subsequent regression. Those showing dissociated poorly differentiated dyskaryotic parabasal cells regressed to negative in two cases and progressed to invasion in nine. This suggests that many examples of spontaneous regression correspond to mild dysplasias which are not precancerous, and overdiagnosis must often have resulted in unnecessary surgical procedures in the past.

`Regressing' and `progressing' groups both included cases in which the spatula had removed coherent pieces of undifferentiated epithelium. These are difficult to interpret cytologically. In nine of them (including four which regressed) the cytological picture was that of carcinoma in situ. The remainder (14 cases) were probably examples of reserve cell hyperplasia, and it is noteworthy that, of the 21 cases subsequently progressing to invasive carcinoma, five were preceded by appearances of this type. It is concluded that cell aggregates suggesting an unusual degree of reserve cell hyperplasia are a danger signal and require careful surveillance.

  相似文献   
22.
Role of phosphoinositides in transmembrane signaling   总被引:27,自引:0,他引:27  
  相似文献   
23.
目的:构建重组表达载体pEGFP-C3-B7.2-MAGE-1,研究人B7.2/MAGE-1基因修饰的食管癌细胞作为瘤苗的抗肿瘤作用.方法:通过RT-PCR扩增B7.2和MAGE-1的cDNA,以pEGFP-C3为载体,构建pEGFP-C3-B7.2-MAGE-1重组载体,通过脂质体转染技术转染人食管癌细胞株EC9706,外周血来源的树突状细胞(DC)负载肿瘤抗原后,与自体T淋巴细胞共培养3天,获得细胞毒性T淋巴细胞(CTL),用四甲基偶氮唑蓝(MTT)法检测CTL对转染和未转染pEGFP-C3-B7.2-MAGE-1的食管癌细胞EC9706的杀伤活性.结果:CTL对转染pEGFP-C3-B7.2-MAGE-1的肿瘤细胞的杀伤活性大于转染pEGFP-C3和未转染细胞的杀伤活性(P<0.05).结论:成功构建了真核共表达载体pEGFP-C3-B7.2-MAGE-1,人B7.2/MAGE-1基因修饰的EC9706肿瘤细胞瘤苗,可诱导出明显的抗EC9706细胞的免疫效应.  相似文献   
24.
25.
The effect of interleukin-1beta (IL-1beta) on urine flow rates and Na(+)/K(+)-ATPase activity and expression was studied in rat intestinal and renal epithelia. The cytokine produced a significant diuretic effect and increased urine flow rate by around 10-fold compared with the control. This effect was considered to be secondary to the well-documented natriuretic effect of the cytokine described in the literature. On the other hand, we have shown previously that IL-1beta inhibits glucose absorption from the jejunum. As sodium excretion and glucose absorption are both dependent on Na(+)/K(+)-ATPase activity, the effect of the cytokine on the renal and intestinal pump was investigated. IL-1beta inhibited, in a dose-dependent manner, the activity of Na(+)/K(+)-ATPase in villus and crypt jejunal cells and in medullary and cortical kidney cells. Western blot analysis revealed a decrease in the protein expression of the enzyme, which was confirmed by the radiolabeled ouabain binding assay. The results suggest that the diuretic and natriuretic effect of IL-1beta and its inhibitory effect on glucose absorption are all due to downregulation of the Na(+)/K(+) pump in the kidney and jejunum.  相似文献   
26.
HIS网络在门诊挂号、收费管理中的应用   总被引:1,自引:0,他引:1  
随着医院现代化的高速发展,医院信息系统(HIS)显得越来越来至关重要。对其要求越来越趋于完善性、全面性、灵活性、快捷性。这样就要求有一套完整的HIS来满足现代化医院管理的需要,实现现代化医院"以人为本"的管理理念,"一切以病人为中心",用现代化的管理理念结合工作需求,构建工作中的"和蔼"关系。  相似文献   
27.
目的 :研究郑氏植物蛋白 (Zheng’splant protein ,ZPP)对淋巴细胞的刺激作用及其在乳腺癌早期诊断与治疗中的应用价值。方法 :采用3 H TdR掺入法测定人外周血淋巴细胞(PBL) )的增殖反应。用流式细胞仪测定ZPP对T淋巴细胞CD3+ 、CD4 + 和CD8+ 抗原表达的调节作用。结果 :ZPP对乳腺癌及其前期病变患者PBL有较强的刺激作用 (SI分别为3.0 0± 1.4 5和 2 .5 3± 0 .80 ) ,明显高于对正常对照组和乳管上皮轻度增生患者PBL的刺激指数 (SI分别为 1.0 6± 0 .17和1.18± 0 .19) (P <0 .0 1)。而PHA对各组PBL的增殖反应均有不同程度的刺激作用 ,但各组间无明显差异 (P >0 .0 5 ) .经ZPP刺激后的PBL中CD3+ 、CD4 + 和CD8+ 细胞均发生增殖反应 ,其中CD4 + 和CD8+ 者更为明显。结论 :ZPP可选择性刺激乳腺癌及其前期病变患者的PBL中T细胞发生增殖反应 ,此作用有可能用于乳腺癌的早期诊断与治疗中  相似文献   
28.
Allergic reactions are triggered via crosslinking of the high-affinity receptor for immunoglobulin E, F(c)epsilonRI. In humans, F(c)epsilonRI is expressed as a tetramer (alphabetagamma(2)) and a trimer (alphagamma(2)). The beta subunit is an amplifier of F(c)epsilonRI surface expression and signaling. Here, we show that as a consequence of alternative splicing, the F(c)epsilonRIbeta gene encodes two proteins with opposing and competing functions. One isoform is the full-length classical beta, the other a novel truncated form, beta(T). In contrast to beta, beta(T) prevents F(c)epsilonRI surface expression by inhibiting alpha chain maturation. Moreover, beta(T) competes with beta to control F(c)epsilonRI surface expression in vitro. We propose that the relative abundance of the products of the beta gene may control the level of F(c)epsilonRI surface expression and thereby influence susceptibility to allergic diseases.  相似文献   
29.
OBJECTIVE: As a result of the HIV epidemic in Africa, much debate exists on whether institutionalized compared with community-based care provides optimum management of infected children. Previous reports calculated 89% mortality by age 3 years among outpatients in Malawi. No similar data are available for infected children in institutionalized care. We characterized patterns of morbidity and mortality among HIV-1-infected children residing at an orphanage in Nairobi. METHODS: Medical records for 174 children followed over 5 years were reviewed. Mortality was analyzed by Kaplan-Meier methods with adjustment to account for survival in the community before admission. Anthropometric indices were calculated to include mean z scores for weight for length and length for age. Low indices reflected wasting and stunting. Opportunistic infections were documented. RESULTS: Of 174 children, 64 had died. Survival was 70% at age 3 years. Morbidity included recurrent respiratory tract infections, gastroenteritis, parotitis, and lymphoid interstitial pneumonitis. No new cases of tuberculosis disease were noted after admission. Mean z scores for length for age suggested overall stunting (z = -1.65). Wasting was not observed (z = -0.39). CONCLUSION: The optimal form of care for HIV-infected children in resource-poor settings may be the development of similar homes. Absence of tuberculosis disease in long-standing residents may have contributed to improved survival. Stunting in the absence of wasting implied that growth was compromised by opportunistic infections and other cofactors.  相似文献   
30.
When administered to animals cadmium is known to accumulate in the liver and kidney causing indentifiable toxicity. However, its binding with cell sap and nucleus and effects on their constituents are poorly known. Since nuclear changes reflect some of the metabolic disturbances and are of value in diagnosis, an attempt has been made to analyse their morphology and chemistry in the liver and kidney of rat after individual and combined treatment with Cd and Zn. Present observations clearly show that cadmium inhibits DNA synthesis by blocking the formation of the enzyme thymidine triphosphate which is prerequisite for DNA synthesis. Zinc exerted a stimulatory effect on DNA and RNA both by increasing the activity of thymidine kinase. Their combined effects were found to be less injurious to the cell. Though these changes could be a secondary or generalized response of nuclei to altered physiological conditions, specific reasons for these changes have been discussed.  相似文献   
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