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991.
BACKGROUND: Systemic to pulmonary arterial collaterals often develop after bidirectional cavopulmonary anastomosis (BCPA). It has been proposed that such collaterals may be related to perioperative outcome and duration of effusions after the modified Fontan procedure. However, the incidence and significance of collaterals after BCPA remain uncertain. METHODS: To evaluate risk factors for, and significance of, such collaterals, we reviewed angiographic and clinical data for all 76 patients who underwent BCPA between January 1990 and June 1996 and had follow-up catheterization during or before 1997. RESULTS: The median age at BCPA was 10 months, and the median duration from BCPA to follow-up catheterization was 18 months. Arterial collaterals were detected on follow-up catheterization in 45 patients (59%). Factors associated with collateral development included a prior right-sided systemic-to-pulmonary arterial shunt, lower pre-BCPA end-diastolic ventricular pressure and pulmonary vascular resistance, and use and duration of cardiopulmonary bypass during the BCPA operation. Fourteen of the 45 patients (30%) underwent coil embolization of the collaterals. Forty-three patients have undergone extracardiac conduit Fontan, with 1 early and 1 late death. Collaterals were present in 22 of these patients, 7 of whom underwent pre-Fontan embolization. The duration from BCPA to Fontan was longer in patients with collaterals, but these patients were not more likely to have prolonged effusions than those without, and the duration of tube thoracostomy was significantly shorter in patients with collaterals. Embolization of collaterals did not affect the duration of effusions. CONCLUSIONS: Systemic-to-pulmonary arterial collaterals are common after BCPA. In contrast to prior reports, collaterals were not associated with a higher incidence of prolonged effusions after the Fontan procedure in our experience, and did not correlate with poor outcome.  相似文献   
992.
Hot-melt extrusion technology was used to produce thin films containing a model drug, lidocaine, and the cellulosic polymers hydroxypropyl cellulose (HPC) and hydroxypropyl methyl cellulose (HPMC). Two film formulations were extruded and compared, one containing only HPC and the other containing HPC:HPMC (80:20). Thermal analysis of the films using differential scanning calorimetry (DSC) suggested that the drug existed in the amorphous condition, which was confirmed by wide angle X-ray diffractometry. Sustained release of the drug was observed from both of the polymer matrices. Dissolution profiles suggested that HPMC retarded the drug release from HPC:HPMC (80:20) films. However, the mechanism of drug release from both of the films was predominantly diffusion of the drug through the polymer matrices. Incorporation of HPMC also increased both adhesive strength and work of adhesion as compared to the HPC-only films.  相似文献   
993.
PURPOSE: Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer. PATIENTS AND METHODS: Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m(2) orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8. RESULTS: Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment. CONCLUSION: The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points.  相似文献   
994.
The p53 gene plays a critical role in cell cycle control, the initiation of apoptosis, and in DNA repair. An Arg/Pro polymorphism at codon 72 of the p53 gene alters the ability of the p53 protein to induce apoptosis, influences the behavior of mutant p53, decreases DNA repair capacity, and may be linked with an increased risk of lung cancer. To further define the role of the p53 codon 72 polymorphism on DNA repair, lung cancer risk, and mutant p53 function, we examined the effect of this polymorphism on mutation of the p53 gene and patient survival in non-small cell lung cancer (NSCLC). Tumor and nonneoplastic (lung or lymphocyte) samples were collected from 182 patients with NSCLC. p53 mutations were detected by direct sequencing and/or the Gene Chip p53 assay in 93 of 182 (51%) tumors. p53 codon 72 polymorphisms were identified by PCR/RFLP analysis. p53 mutations were significantly (P = 0.01) associated with the number of codon 72 Pro alleles: Pro/Pro homozygotes, 17 of 26 (65%); Arg/Pro heterozygotes, 45 of 79 (57%); and Arg/Arg homozygotes, 31 of 77 (40%). The number of codon 72 Pro alleles was independently associated with p53 mutations (odds ratio, 1.97; 95% confidence interval, 1.14-3.40; P = 0.01) in a multiple logistic regression model. The codon 72 polymorphism did not influence patient survival in either the entire patient group or among patients with p53 mutant tumors. In summary, the p53 Pro allele is associated with an increased frequency of p53 mutations in NSCLC.  相似文献   
995.
996.
Women who are born with constitutional heterozygous mutations of the BRCA1 gene face greatly increased risks of breast and ovarian cancer. The product of the BRCA1 gene is involved in the repair of double-stranded DNA breaks and it is believed that increased susceptibility to DNA breakage contributes to the cancer phenotype. It is hoped therefore that preventive strategies designed to reduce chromosome damage will also reduce the rate of cancer in these women. To test for increased mutagenicity of cells from BRCA1 carriers, the frequency of chromosome breaks was measured in cultured blood lymphocytes following in vitro exposure to bleomycin in female BRCA1 carriers and was compared with noncarrier relatives. The frequency of chromosome breaks was also measured in BRCA1 carriers following oral selenium supplementation. Carriers of BRCA1 mutations showed significantly greater mean frequencies of induced chromosome breaks per cell than did healthy noncarrier relatives (0.58 versus 0.39; P < 10(-4)). The frequency of chromosome breaks was greatly reduced following 1 to 3 months of oral selenium supplementation (mean, 0.63 breaks per cell versus 0.40; P < 10(-10)). The mean level of chromosome breaks in carriers following supplementation was similar to that of the noncarrier controls (0.40 versus 0.39). Oral selenium is a good candidate for chemoprevention in women who carry a mutation in the BRCA1 gene.  相似文献   
997.
There have been a significant number of reports on the clinical utility of measurement of 'hyperglycosylated' isoforms of the pregnancy hormone, human chorionic gonadotropin (hCG). Although there are a variety of hCG isoforms which can be termed 'hyperglycosylated', the measurements were all made using a unique antibody designated B152. This antibody was raised using a choriocarcinoma-derived form of hCG, which was hyperglycosylated with N- and O-glycans and was also 100% 'nicked' hCG. Antibody B152 was recently mapped to a linear epitope around a single O-glycan on the beta-subunit of hCG at residue number 132. Thus, the antibody can only measure isoforms of hCG that possess a core 2 type of branched O-glycan on this portion of the hCG beta-subunit. Isoforms that are hyperglycosylated in the hCG alpha-subunit or only on the N-glycans of hCGbeta will not be recognized by antibody B152. Apparently, measurements of these core 2 hCG isoforms have important clinical application in early pregnancy during which they are the predominant isoform of hCG until the 6th week of gestation. The secretory pattern of these isoforms can be used to predict the health status of the pregnancy in fertility clinics. Moreover, the measurements of these core 2 hCG isoforms are more useful than standard hCG for the prediction of Down syndrome pregnancies. The core 2 isoforms are also of important use in cancer diagnosis and monitoring since their concentration appears to correlate with malignancy.  相似文献   
998.
BACKGROUND: BAY 43--9006, an oral multi-kinase inhibitor, targets serine-threonine kinases and receptor tyrosine kinases, and affects the tumor and vasculature in preclinical models. Based on its pharmacologic effect, it may be a useful cancer treatment. This study determined the maximum tolerated dose (MTD) of BAY 43-9006 in 42 patients with advanced, refractory metastatic or recurrent solid tumors. Dose-limiting toxicities (DLTs), safety, pharmacokinetics and tumor response were also evaluated. PATIENTS AND METHODS: In this open-label, phase I, dose-escalation study, BAY 43--9,006 was administered orally in repeated cycles of 35 days (28 days on/7 days off). Eight doses were investigated: from 50 mg every fourth day to 600 mg twice daily. Treatment continued until unacceptable toxicity, tumor progression or death. RESULTS: The MTD was 400 mg twice daily. BAY 43-9006 was well tolerated, with mild to moderate toxicities; only six patients discontinued study therapy due to adverse events. DLTs consisted of hand-foot skin reaction in three of seven patients receiving 600 mg twice daily. Stable disease was achieved in 22% of patients; median duration of stable disease was 7.2 months. Consistent with its observed half-life of approximately 27 h, BAY 43-9, 006 accumulated on multiple dosing. Increases in exposure were less than proportional to the increases in dose. CONCLUSIONS: Results indicate that further clinical investigation of BAY 43--9006 is warranted, and suggest it could be a promising future therapy for patients with cancer.  相似文献   
999.
BACKGROUND: Insulin-like growth factor-II (IGF-II) stimulates cell proliferation and is considered a potential risk factor for colorectal cancer. Tumor levels of IGF-II seem to positively correlate with colorectal cancer cell proliferation. This investigation examined the association of circulating IGF-II to the proliferating cell index (PCI) of tumor and matched normal mucosa in patients with colorectal neoplasia. METHODS: Circulating IGF-II level (ng/mL) was determined in the peripheral blood plasma by ELISA. The proliferating cells in tumor or matched normal mucosa were immunohistochemically stained using the primary antibody against Ki-67. Computer image analysis was used and PCI was expressed as the percentage of Ki-67-positive cells/total counted cells. RESULTS: Sixty-four patients were evaluated; 45 had colorectal neoplasia (27 males/18 females; mean age, 66.8 +/- 11.8 years) and 19 had hyperplastic polyps (6 males and 13 females; mean age, 58.4 +/- 14.4 years). Among patients with colorectal neoplasia, blood IGF-II levels were positively correlated with PCI in the matched normal mucosa (r = 0.46, P < 0.05) but not in the tumor. In patients with hyperplastic polyps, blood IGF-II levels were not correlated with the PCI in the polyps. Blood IGF-II levels were higher in colorectal cancer patients with Dukes' C/D stage (P < 0.01) or with positive lymph nodes (P < 0.01). CONCLUSION: Circulating IGF-II positively correlated with PCI in normal colonic mucosa of patients with colorectal neoplasia, suggesting that IGF-II may have a role in initiating the carcinogenic pathway by stimulating cell proliferation. Blood IGF-II was increased in advanced colorectal cancer, indicating that it might enhance colorectal cancer progression and be a useful marker of poor prognosis.  相似文献   
1000.
PURPOSE: To compare long-term survival in patients with locally advanced or metastatic transitional cell carcinoma (TCC) of the urothelium treated with gemcitabine/cisplatin (GC) or methotrexate/vinblastine/doxorubicin/cisplatin (MVAC). PATIENTS AND METHODS: Efficacy data from a large randomized phase III study of GC versus MVAC were updated. Time-to-event analyses were performed on the observed distributions of overall and progression-free survival. RESULTS: A total of 405 patients were randomly assigned: 203 to the GC arm and 202 to the MVAC arm. At the time of analysis, 347 patients had died (GC arm, 176 patients; MVAC arm, 171 patients). Overall survival was similar in both arms (hazard ratio [HR], 1.09; 95% CI, 0.88 to 1.34; P = .66) with a median survival of 14.0 months for GC and 15.2 months for MVAC. The 5-year overall survival rates were 13.0% and 15.3%, respectively (P = .53). The median progression-free survival was 7.7 months for GC and 8.3 months for MVAC, with an HR of 1.09. The 5-year progression-free survival rates were 9.8% and 11.3%, respectively (P = .63). Significant prognostic factors favoring overall survival included performance score (> 70), TNM staging (M0 v M1), low/normal alkaline phosphatase level, number of disease sites (相似文献   
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