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81.
82.
We report a case of bronchobiliary fistula between a liver hydatid cyst and the middle lobe of the right lung. It is also reviewed the etiology, pathogenesis, clinical features, diagnosis and treatment of bronchobiliary fistulas.  相似文献   
83.
A metabolic interaction between stiripentol (STP), an anticonvulsant agent that inhibits the activity of several cytochromes P450 (P450s), and clobazam (CLB), a 1,5-benzodiazepine, used in association with STP in severe myoclonic epilepsy in infancy was observed in vivo. This interaction was characterized in vitro using cDNA-expressed CYP3A4 and CYP2C19 (main P450 involved in CLB metabolism) to calculate K(i) and IC(50) of stiripentol in comparison with ketoconazole (CYP3A4 inhibitor) and omeprazole (CYP2C19 inhibitor). STP inhibited N-demethylation of CLB to N-desmethylclobazam (NCLB) mediated by CYP3A4 (noncompetitively) and CYP2C19 (competitively) with K(i) = 1.59 +/- 0.07 and 0.516 +/- 0.065 microM and IC(50) = 1.58 microM [95% confidence interval (CI95%) = 1.20-2.08] and 3.29 microM (CI95% = 1.87-5.79), respectively. STP inhibited also more strongly the 4'-hydroxylation of NCLB to 4'-hydroxy-N-desmethylclobazam by CYP2C19 [competitive interaction with K(i) = 0.139 +/- 0.025 microM and IC(50) = 0.276 microM (CI95% = 0.206-0.371)]. The inhibitory effect of STP on CLB demethylation by CYP3A4 was much weaker than that of ketoconazole [IC(50) = 0.023 microM (CI95% = 0.016-0.033)], whereas its effect on NCLB hydroxylation by CYP2C19 was much higher than that of omeprazole [IC(50) = 2.99 microM (CI95% = 2.11-4.24)]. The major in vitro inhibitory effect of STP on CLB metabolism and mostly on NCLB biotransformation is consistent with the changes in vivo in CLB and NCLB plasma concentrations in children treated by the association CLB/STP.  相似文献   
84.
This study has aimed to evaluate the usefulness of repeated treatment with 89Sr in patients with prostate neoplasm and metastatic bone pain. Seventeen patients with partial or complete response after the first dose were retreated with two or more doses (total of 39 doses). The Karnofsky functional status, pain and degree of analgesia were assessed. After the first dose the response was good in 68% of the patients and partial in 32%. After the second dose, the response was good in 62% of the patients, partial in 15% and there was no response in 23% of the cases. The pre-treatment Karnofsky functional status and duration of the effect of 89Sr was lower after the second dose (p = 0.03, p = 0.02), but there were no statistically significant differences in the type of response. In conclusion, re-treatment with 89Sr can be administered safely and with a similar response to that achieved after the first dose.  相似文献   
85.
86.
Antiestrogen resistance is frequently observed in patients after longterm treatment with tamoxifen, a nonsteroidal antiestrogen widely used for endocrine therapy of breast cancer. In vitro studies in resistant cells showed that the expression of natural estrogen-responsive genes is frequently altered. Using MVLN cells, an MCF-7-derived cell model, we previously demonstrated that 4-hydroxytamoxifen (OHT) treatment irreversibly inactivated an estrogen-regulated chimeric luciferase response by a direct effect of the drug and not through a cell selection process (E. Badia et al., Cancer Res., 54: 5860-5866, 1994). In the present study, we present tamoxifen-resistant but still estrogen-dependent clones isolated after long-term treatment of MVLN cells with OHT and show that progesterone receptor (PR) expression was irreversibly decreased in some of these clones, whereas the PRA:PRB ratio of residual PR remained unchanged. The irreversible inactivation of both chimeric luciferase gene and PR gene expression was associated with the disappearance of DNase 1-hypersensitive sites. In the case of the chimeric gene, at least one of these sites was close to the estrogen responsive element. Genomic sequencing analysis of a clone with very low PR content did not reveal any methylation on CpG dinucleotides or any mutation in the PR gene promoter region. In all of the resistant clones tested and independently of their PR content, estrogen receptor expression was only lowered by half and remained functional, whereas pS2 expression was not modified. We also observed that the residual luciferase activity level (1-2%) of the MVLN clones, the luciferase expression of which had been irreversibly inactivated, was raised 4-fold by trichostatin A treatment. We conclude that long-term OHT treatment may modify the chromatin structure and thus could contribute to differentially silencing natural target genes.  相似文献   
87.
In order to monitor the (anti)steroid activity of environmental samples, we established stable cell lines expressing luciferase under the control of estrogens, androgens, progestives and glucocorticoids. The breast cancer MCF-7 cells which express the estrogen receptor (ER), the glucocorticoid receptor (GR) and the progesterone receptor (PR) were transfected by an estrogen (ERE-Glob-Luc) or a glucocorticoid/progestin/androgen (MMTV-Luc) regulated luciferase plasmid in order to enable the detection of compounds which bind both ER, PR and GR (MELN and MMLN cells). Human prostatic cells PC3 were stably transfected by both an androgen receptor gene and the MMTV-luciferase plasmid (PALM cells). These three cellular models were validated as tools to check the estrogenic, progestive, glucocorticoid and androgenic activities using several potential xenohormones and environmental samples. As these environmental samples were fractionated after solid phase extraction to isolate active compounds, we used these cellular models to monitor the different fractions. In the estrogenic model mid-polar fractions of environmental samples were found active while in the androgenic model, the same fractions had antagonist activity.  相似文献   
88.
Molecular biology of malignant melanoma and other cutaneous tumors   总被引:5,自引:0,他引:5  
Skin cancer is the most common cancer worldwide. Its incidence is doubling every 15–20 years likely because of an aging population, changes in behaviour towards sun exposure, and increased UV light fluency at the earth surface due to ozone depletion. In this review, we summarize the most important genetic changes contributing to the development of malignant melanoma, basal cell carcinoma and squamous cell carcinoma, the main tumor entities arising in the skin. While our understanding of the oncogenes and tumor suppressor genes involved in the development and progression of skin tumors is still fragmentary, recent advances have shown alterations affecting conserved signalling pathways that control cellular proliferation and viability. These pathways includeINK4a/Rb,ARF/p53, RAS/MAPKs, and sonic hedgehog/Gli. Supported by an unrestricted educational grant by Bristol-Myers Squibb.  相似文献   
89.
Radioimmunoscintigraphy (RIS) with BW 431/26 monoclonal antibody (MoAb) labelled with 99Tcm (962 MBq) has been performed in 64 patients with colorectal carcinoma, one of them with two independent tumours. The group consisted of 46 primary lesions, 15 pelvic recurrences and four suspected recurrences which were shown to be liver metastases. Imaging of liver was obtained in all patients, but surgical liver examination was performed in only 56 of them. Planar scans were obtained at 4 and 24 h postinjection. Tomographic images were also performed in five patients. The final diagnosis was confirmed in all patients by their clinical course and by findings at surgery and pathology. A comparative study between the RIS results and the final diagnosis gave a global sensitivity in primary tumours and pelvic recurrences of 59.7% with an accuracy of 59.0%. When rectal tumours were excluded, the results were 81.1 and 84.9%, respectively. In liver metastases the sensitivity was 50%, with an accuracy of 85.7% and a specificity of 100%. No correlation has been found between CEA serum levels and lesion detection. In conclusion, RIS is a useful technique for the study and localization of colorectal tumours, being also indicated in patients with normal carcinoembryonic antigen (CEA) serum levels and clinical suspicion of illness.  相似文献   
90.
On December 14, 1985, the Teller chairlift at the Keystone, Colorado, ski area collapsed, throwing 60 of the 372 people aboard to the ground from heights up to 50 feet. Initial triage and management of the victims was carried out by the local ski patrol, the on-duty physician at the area's Snake River Health Services Clinic, and by volunteer physicians and nurses present at the scene. Thirty-three people required immediate evacuation to hospitals, most of them being transported 75 miles by helicopter air ambulance to level I and II trauma centers in the Denver metropolitan area. Eighteen of these air-evacuated patients were in serious or critical condition. Less seriously injured victims were treated at local medical facilities. The scene evacuation was carried out by helicopter and ground vehicles in accordance with an existing disaster plan coordinated by the Colorado Trauma Institute (CTI). The unique problems posed by a mass casualty incident in a remote mountain location are emphasized by this tragedy. Patient salvage due to the efficacy of a regionally organized trauma system is clearly demonstrated.  相似文献   
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