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71.
The effects of the 5-HT(1A) receptor antagonist WAY 100635 on recognition memory were investigated in two different amnestic models in the rat by using the object recognition task. WAY 100635 at 1 mg/kg, but not at 0.3 mg/kg, counteracted scopolamine-induced performance deficits in the acquisition version of this behavioral paradigm. At the same dose, WAY 100635 antagonized extinction of recognition memory in the normal rat, suggesting that it affected acquisition, storage and retrieval of information. These results support and extend prior findings that interactions between the serotonergic and cholinergic systems are relevant to cognition and indicate that WAY 100635 modulates different aspects of recognition memory.  相似文献   
72.
Post-menopausal hormonal therapy and gallbladder cancer risk   总被引:3,自引:0,他引:3  
The relation between post-menopausal hormone replacement therapy (HRT) and gallbladder cancer was analyzed in women above age 45 years, using data of a case-control study conducted in Italy between 1985 and 1997, on 31 incident, histologically confirmed cases and 3,702 controls in hospital for acute, non-neoplastic conditions. The multivariate odds ratio (OR) was 3.2 (95% confidence interval: 1.1-9.3) for those who had ever used HRT and the OR tended to rise with longer duration. Although based on small numbers, due to the rarity of the disease, these findings provide the first direct epidemiological evidence of an association between HRT and gallbladder cancer.  相似文献   
73.
We have previously shown that the growth of human tumor xenografts in immunodeficient mice can be efficiently suppressed upon infection with the autonomous parvovirus H-1 or with cytokine-transducing derivatives thereof. To further evaluate the benefits of implementing parvoviruses in cancer gene therapy, we have created a new recombinant vector, MVMp/IP-10, transducing the immunoactive, antiangiogenic chemokine IP-10, and used this virus to treat syngeneic tumors grown in immunocompetent mice. Intratumoral/intraperitoneal administration of only 3 x 10(7) replication units of MVMp/IP-10 per animal strongly inhibited the progression of established H5V cell-induced vascular tumors, a highly malignant mouse model for human cavernous hemangioma and Kaposi's sarcoma. Retardation of recurrent tumor growth and suppression of life-threatening metastatic dissemination to internal organs were accompanied by a striking delay in hemangioma-associated mortality. Parental MVMp did not have a significant effect under these conditions up to the dose of 10(10) infectious units/animal, but had strong antihemangiosarcoma activity when used to infect H5V cells ex vivo prior to implantation. In all cases, virus therapy was very well tolerated. Virus-induced suppression of hemangiosarcoma was dependent on host T cells and associated with intratumoral persistence of IFN gamma-expressing cytotoxic lymphocytes, and led to the reduced expression of hepatic plasminogen activator inhibitor-1 (PAI-1), a metastasis-linked marker. This proof of principle study demonstrates that MVMp/IP-10 can aid the treatment of vascular tumors and that autonomous parvovirus-based vectors can be considered potent tools for cancer gene therapy purposes.  相似文献   
74.
BACKGROUND: Laser debulking and prosthetic stents are useful modalities in the palliative treatment of initial inoperable or recurrent lung cancer. Recently, endobrochial brachytherapy was introduced to extend the duration of palliation and reduce the number of endoscopic treatments. This trial compares Nd-YAG laser alone and associated to high dose rated (HDR)-brachytherapy. PATIENTS AND METHODS: From 1995 to 1998, 29 consecutive patients, with non-small cell lung cancer (NSCLC) and central airway involvement, were randomized in two groups: group 1 (15 patients) received Nd-YAG laser only; group 2 (14 patients) underwent a combined Nd-YAG laser/ HDR brachytherapy treatment. RESULTS: There was no mortality or morbidity related to the treatment. The period free from symptoms was 2.8 months for group 1 and increased to 8.5 months in group 2 (P<0.05). The disease's progression free period grew from 2.2 months of group 1 to 7.5 months of group 2 (P<0.05) and the number of further endoscopic treatment reduced from 15 to 3 (P<0.05). CONCLUSION: The results confirm the potential of brachytherapy to prolong relief from symptoms, lessen disease progression and reduce costs of treatment. A detailed analysis is presented of both groups.  相似文献   
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Extremely low frequency (ELF) electric fields (EF) and magnetic fields (MF) are generated during the production, transmission, and use of electrical energy. Although epidemiology studies suggest that there is a cancer risk associated with exposure to ELF-MF, short-term genotoxicity assays with bacteria and mammalian cells have produced inconsistent results. In the present study, we investigated the possible genotoxicity of ELF-MF by using the Tradescantia-micronucleus (Trad-MN) assay, a sensitive, reproducible, well-standardized assay for genotoxicity testing. A 50 Hz ELF-MF was generated by a laboratory exposure system consisting of a pair of parallel coils in a Helmholtz configuration. Exposure of Tradescantia (clone # 4430) inflorescences to the ELF-MF, at a flux density (B) corresponding to 1 mT, for 1, 6, and 24 h resulted in a time-dependent increase in MN frequency. The results indicate that a 50 Hz MF of 1 mT field strength is genotoxic in the Trad-MN bioassay and suggest that this assay may be suitable as a biomonitor for detecting the genotoxicity of ELF-MF in the field.  相似文献   
79.
Congenital 21-alpha hydroxylase deficiency is a syndrome characterized by a cortisol synthesis deficiency and, rarely, by testicular masses. We present a case of bilateral nodular hyperplasia of the testis without adrenal hyperplasia in a patient affected by 21-alpha hydroxylase deficiency. This mass mimicked a testicular tumor and made differential diagnosis with a Leydig cell tumor extremely difficult. Multiple hard nodules (1 cm in diameter) could be palpated in both testes but were more prominent on the right. After an unsuccessful 30-day trial of an adrenocorticotropic hormone suppression regimen with dexamethasone (0.5 mg/qid), a right total orchifunicolectomy was performed. The final histological diagnosis was that of multiple, well-circumscribed nodules consisting of cord-like and microalveolar-like gonadal stroma, typical of an adrenogenital syndrome, and fibrosis. Differential diagnosis between testicular nodules in patients with congenital adrenal hyperplasia and Leydig cell tumors is a major clinical challenge. In cases of cortisol suppression resistant testicular masses, a serum adrenal hormone profile obtained from the gonadal vein and histology of the testicular nodule (with parenchyma sparing surgery) are recommended to obtain a correct diagnosis.  相似文献   
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