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991.
六味丹坤方改善老年小鼠DNA损伤及其修复能力的观察   总被引:2,自引:0,他引:2  
本文应用FADU法从DNA的自然损伤、抗损伤能力及损伤后的修复能力方面观察了补肾化瘀方药六味丹坤对老年小鼠脾淋巴细胞DNA结构完整性的影响。实验表明:(1)老年小鼠DNA损伤较青年组严重,用药后改善。(2)10Gy60Co 射线照射后,老年小鼠辐射抗性较青年组低,用药后可以增强其对辐射的抗性。(3)照射后温育60分钟结果显示,老年小鼠修复DNA损伤能力有所下降,给药后有一定程度的提高。  相似文献   
992.
Thirteen cases of psoas abscess were treated by surgical drainage through Petit's triangle. This underutilized anatomic space provides a simple and effective route for drainage of retroperitoneal abscesses. Correspondence to: K. L. N. Rao  相似文献   
993.
Eight second malignant tumours developed in a population-based series of 218 patients diagnosed with renal tumours in childhood: renal cell carcinoma of the contralateral kidney, hepatocellular carcinoma, Hodgkin's disease, and 4 basal cell and 1 squamous cell carcinomas of skin. Excess risk of developing a second malignancy (excluding skin carcinomas but including a registrable spinal neurofibroma) was 14.7 (95% Cl 4.0-37.7, P = 0.0003) for Wilms' tumour patients. Cumulative incidence of second malignant neoplasms (excluding skin carcinoma) was zero at 10 years, 5.0% at 20 years, and 10.2% at 30 years. The most common second neoplasms seen were benign osseous/chondromatous tumours and 4 of the 7 Wilms' tumour patients with malignant tumours had previous or synchronous tumours of this kind. Development of bony exostoses may be a marker for those patients at particularly high risk of subsequent malignancy. © 1994 wiley-Liss, Inc.  相似文献   
994.
To determine the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) of irinotecan and raltitrexed given as sequential short infusions every 3 weeks, 33 patients with pretreated gastrointestinal adenocarcinoma (31 colorectal, 2 oesophagogastric) entered this open label dose-escalation study. For the first five dose levels patients received irinotecan 175-350 mg m(-2) followed by raltitrexed 2.6 mg m(-2). Level VI was irinotecan 350 mg m(-2) plus raltitrexed 3.0 mg m(-2), level VII was irinotecan 400 mg m(-2) plus raltitrexed 2.6 mg m(-2); 261 courses were administered. Only one patient at dose levels I-V experienced DLT. At level VI, 5/12 patients experienced DLT: one had grade 3 diarrhoea and lethargy, one had grade 4 diarrhoea and one had lethargy alone. Two others had lethargy caused by disease progression. There was no first-cycle neutropenia. At level VII, 3/6 patients experienced dose-limiting lethargy, one also had grade 3 diarrhoea. Dose intensity fell from over 90% for both drugs at level VI to 83% for irinotecan and 66% for raltitrexed at level VII. Lethargy was therefore the DLT, and level VII the MTD. Pharmacokinetic data showed no measurable drug interaction; 6/30 patients (20%) had objective responses. This combination is active with manageable toxicity. Recommended doses for further evaluation are irinotecan 350 mg m(-2) and raltitrexed 3.0 mg m(-2).  相似文献   
995.
BACKGROUND: Hemangiopericytoma (HPC) is a soft-tissue neoplasm most commonly seen in adults; only 5-10% of cases occur in children. Childhood HPC comprises two distinct clinical entities. In children older than 1 year, it behaves in a manner similar to adult HPC. Infantile HPC, however, although histologically identical to adult HPC, has a more benign clinical course. The reasons for these differences in the natural history of HPC are not well understood. METHODS: The authors reviewed the clinicopathologic features of HPC as well as the treatment and outcomes of the 12 children (9 males and 3 females) treated for this disease at St. Jude Children's Research Hospital over a 35-year period. RESULTS: At diagnosis, 9 patients were older than 1 year and 3 were younger than 1 year. Among the 9 older patients, tumors were most commonly found in the lower extremities (n = 5). One patient had been treated for acute lymphoblastic leukemia 15 years earlier. One patient had metastatic disease at diagnosis, and three had unresectable tumors. Two patients experienced objective responses to chemotherapy. Three patients died of disease progression. Among the three infants, two had unresectable disease at diagnosis, and both experienced excellent responses to neoadjuvant chemotherapy. In one case, the response of the tumor to chemotherapy correlated with maturation to hemangioma. All three infants are alive without evidence of disease. CONCLUSIONS: HPC in children older than 1 year does not differ from adult HPC, and aggressive multimodality therapy is required. Infantile HPC, on the other hand, is characterized by better clinical behavior, with documented chemoresponsiveness and spontaneous regression, and requires a more conservative surgical approach. In some cases of infantile HPC, this benign behavior correlates with maturation to hemangioma.  相似文献   
996.
BACKGROUND: Carcinoma of cervix is the most common cancer found among the women of India. Though cervical cytology screening was effective in preventing carcinoma of cervix in developed nations, it is considered unsuitable in developing countries. Recent research has established an etiological link between human papillomavirus infection and carcinoma of cervix. In this review, an attempt is made to answer the question, 'whether carcinoma of cervix can be prevented with human papillomavirus vaccine?' METHODS: Literature search using Pubmed and Medline was carried out and relevant articles were reviewed. RESULTS: There is ample experimental evidence to show that DNA of human papillomavirus integrates with cervical cell genome. Viral genes E6 and E7 of HPV type 16 and 18 inactivate p53 function and Rb gene, thus immortalize the cervical epithelial cells. Recombinant vaccines blocked the function of E6 and E7 genes preventing development of papillomas in animals. Vaccination with HPV-VLPs encoding for genes of E6 and E7 neutralizes HPV integrated genome of malignant cells of uterine cervix. CONCLUSIONS: Based on experimental evidence, it is possible to prevent carcinoma of cervix with human papillomavirus vaccine, IMPLICATIONS: Further research is necessary to identify a effective and safe HPV vaccine, routes of administration and characteristics of potential beneficiaries.  相似文献   
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