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81.
The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality.  相似文献   
82.
83.
PURPOSE: To test the hypothesis that common sequence variants of cell cycle control genes may affect lung cancer predisposition. EXPERIMENTAL DESIGN: We explored lung cancer risk associations of 11 polymorphisms in seven cell cycle genes in a large case-control study including 1,518 Caucasian lung cancer patients and 1,518 controls. RESULTS: When individuals with variant-containing genotypes were compared with homozygous wild-type carriers, a significantly increased lung cancer risk was identified for polymorphisms in p53 intron 6 [rs1625895; odds ratio (OR), 1.29; 95% confidence interval (95% CI), 1.08-1.55] and in p27 5' untranslated region (UTR; rs34330; OR, 1.27; 95% CI, 1.01-1.60). Compared with homozygous wild-types, the homozygous variant genotypes of STK15 F31I and CCND1 G870A were associated with a significantly altered lung cancer risk with ORs of 0.58 (95% CI, 0.37-0.90) and 1.26 (95% CI, 1.03-1.53), respectively. To assess the cumulative effects of all the investigated polymorphisms on lung carcinogenesis, we conducted a combined analysis and found that compared with low-risk individuals with few adverse alleles, individuals with more adverse alleles had an increased risk in a significant dose-dependent manner (P(trend) = 0.041). This pattern was more evident in ever smokers (P(trend) = 0.037), heavy smokers (P(trend) = 0.020), and older subjects (P(trend) = 0.011). Higher-order gene-gene interactions were evaluated using the classification and regression tree analysis, which indicated that STK15 F31I and p53 intron 6 polymorphisms might be associated with lung carcinogenesis in never/light-smokers and heavy smokers, respectively. CONCLUSIONS: Our results suggest that cell cycle gene polymorphisms and smoking may function collectively to modulate the risk of lung cancer.  相似文献   
84.
Expression of telomerase is one of the hallmarks of tumor cells and has been used as a diagnostic biomarker and a therapeutic target in cancer. Novel findings have shown that telomerase activation in normal human epithelial cells may affect expression of several cancer-related genes, such as growth-related genes and c-myc gene, suggesting a possible role of telomerase in tumor initiation. Therefore, we hypothesized that individuals who are sensitive to mutagen challenge in terms of induced telomerase activity might have increased cancer risk. We tested this hypothesis in a bladder cancer case-control study (51 cases and 51 matched controls) by measuring baseline and gamma-radiation-induced telomerase activities in peripheral blood lymphocytes. We found a significantly higher gamma-radiation-induced telomerase activity in bladder cancer cases compared with the controls (1.34 versus 1.23; P = 0.044). A similar finding was also observed using the normalized telomerase activity (ratio of gamma-radiation induced versus baseline; 1.49 versus 1.19; P < 0.001). In further categorizing the telomerase activity using 75% of the normalized value in the controls as a cutoff point, we found a significantly increased risk for bladder cancer associated with higher induced telomerase activity (adjusted odds ratio, 3.62; 95% confidence interval, 1.38-9.51). In quartile analysis, a dose-response association was noted between the induced telomerase activity and increased bladder cancer risk (P(trend) = 0.005). Our findings provide the first evidence linking the mutagen-induced telomerase activity in peripheral blood lymphocytes to the risk of bladder cancer, which warrants further investigation in large-sized studies and other cancer types.  相似文献   
85.
目的 观察肝细胞生长因子(HGF)对视网膜色素上皮(RPE)细胞屏障功能的影响以及RPE内过度表达HGF导致视网膜脱离(RD)的病理机制。 方法 编码HGF(AdCMV.HGF)、绿色荧光蛋白(Ad CMV.GFP)的E1/E3缺失的腺病毒载体,以5×104 噬斑形成单位(pfu)/眼注射到成年有色兔的视网膜下。检查注射后3、7、14、28 d时的眼底及组织病理变化,利用免疫组织化学和酶联免疫吸附试验(ELISA)方法检测HGF在视网膜和玻璃体的表达水平。 结果 对照组注射Ad CMV.GFP眼显示GFP几乎仅表达于PRE单核细胞层,AdCMV.HGF注射眼在注射点处的PRE细胞出现强的HGF免疫阳性反应。玻璃体内HGF的表达水平在注射7 d后达到最高峰、28 d后降低到基础水平。在HGF的表达期内AdCMV.HGF注射眼出现慢性RD和脉络膜慢性炎症。在RD区域,视网膜下的空间内可见增生性的RPE细胞,部分实验兔眼还产生多层的细胞膜结构。 结论 RPE内过度表达的HGF能引发慢性浆液性RD,同时伴有视网膜下RPE增生。提示HGF可能作为治疗RD的作用靶点。(中华眼底病杂志,2007,23:193-197)  相似文献   
86.
OBJECTIVE: To report a preliminary study on the efficacy of a gonadotropin-releasing hormone antagonist (Nal-Glu) for preventing premature luteinizing hormone (LH) and progesterone (P) rise in controlled ovarian hyperstimulation using clomiphene citrate (CC) and human menopausal gonadotropin (hMG). DESIGN: Participants in the study formed two groups. Both groups received CC-hMG and Nal-Glu. Group II differs from group I for receiving human chorionic gonadotropin (hCG) and blood samples for 10 days after the second Nal-Glu injection. SETTING: Centre de Fecondation in Vitro, H?pital Antoine Béclère. PATIENTS: Eleven women 25 to 34 years of age and having normal menstrual cycles using barrier method of contraception not attempting pregnancies participated in the study. INTERVENTION: Daily blood samples, pelvic ultrasound, and CC-hMG/Nal-Glu/hCG administration. MAIN OUTCOME MEASURES: (1) Spontaneous LH surge and P rise, follicular growth, and plasma E2 levels in cycles with CC-hMG/Nal-Glu administration and (2) luteal phase after hCG injection in subjects previously treated with CC-hMG/Nal-Glu. RESULTS: Plasma E2 level increased from 983 +/- 80 pg/mL (mean +/- SEM) on the day of the first Nal-Glu administration to 1,159 +/- 102 and 1,610 +/- 114 pg/mL (mean +/- SEM) 24 and 48 hours later. In 10 women, LH and P remained low for at least 96 hours after the first Nal-Glu administration. In one subject, plasma LH was already elevated at the time of the first Nal-Glu injection. In women who received hCG, plasma E2 and P reached a maximum of 1,258 +/- 313 pg/mL and 50.3 +/- 12.8 ng/mL (mean +/- SEM), respectively, on the 6th day of the luteal phase. CONCLUSION: Our results suggest that timely Nal-Glu injections can prevent LH and P rise for at least 96 hours, in spite of increasing levels of plasma E2. Moreover, Nal-Glu had no adverse effect on the kinetic of E2 rise, the follicular growth, or on the post-hCG hormonal profile.  相似文献   
87.
88.
Blood pressure, proteinuria, and plasma fibronectin and plasminogen activator inhibitor-1 levels were measured in 120 apparently healthy normotensive primigravid women during the first, second, and third trimesters of pregnancy and 2 days post partum. Thirty-two women developed hypertension (diastolic blood pressure greater than or equal to 90 mm Hg) that in 17 women was associated with proteinuria (greater than 0.3 gm/day). Fibronectin levels were 83% +/- 22% of normal (mean +/- SD) during the first trimester and 75% +/- 20% at term in the healthy women but increased from 94% +/- 36% to 187% +/- 36% in the women who developed gestational hypertension (with or without proteinuria) (p less than 0.0001). Plasminogen activator inhibitor-1 levels increased from 26 +/- 19 ng/ml to 110 +/- 86 ng/ml in healthy women and from 32 +/- 35 ng/ml to 290 +/- 90 ng/ml in hypertensive women (p less than 0.001). Increased levels of fibronectin at 25 to 36 weeks of pregnancy (greater than or equal to mean + 2 SD of the healthy women, or greater than 140%) were found in 31 of the 32 women with gestational hypertension with or without proteinuria and in 5 of the 88 healthy women (sensitivity 96%, specificity 94%). Fibronectin levels increased 3.6 +/- 1.9 weeks earlier than the onset of hypertension and/or proteinuria. Increased levels of plasminogen activator inhibitor-1 at 25 to 32 weeks (greater than or equal to 280 ng/ml) were found in 16 of the 32 women who developed gestational hypertension with or without proteinuria and in 4 of the 88 healthy women (sensitivity 50%, specificity 95%). We conclude that increased fibronectin levels are the best predictor of gestational hypertension with or without proteinuria and that its level in plasma increases several weeks before the development of hypertension.  相似文献   
89.
Mechanisms of gastro-oesophageal reflux were studied by oesophageal manometry and pH monitoring in 33 children: nine controls, 15 with gastro-oesophageal reflux alone, and nine with reflux oesophagitis. A total of 122 episodes of reflux were analysed in detail: 82 (67%) were synchronous with swallowing and 40 (33%) asynchronous. Infants with trivial symptoms had gastro-oesophageal reflux synchronous with swallowing, whereas those with serious symptoms had slower acid clearance and asynchronous reflux. There were significant differences in lower oesophageal sphincter pressure and amplitude of oesophageal contractions between controls and patients with both gastro-oesophageal reflux and reflux oesophagitis. In reflux oesophagitis there was a decrease in lower oesophageal sphincter pressure and the contractions had a bizarre waveform suggesting a neuropathic process.  相似文献   
90.
The response to a single oral dose of the antiprogesterone RU 486 was studied in the midluteal phase in 26 normal women. Each subject received a dose between 50 and 800 mg RU 486 on days 6 to 8 after the luteinizing hormone surge and blood samples were taken over the following 48 hours. Another group of five patients received a single oral dose of 200 mg RU 486 and blood sampling was extended for 14 days. Menses were induced in all women but one within 3 days after RU 486 administration. Two distinct patient populations emerged. In nine of the subjects, there was a single bleeding episode and the treatment cycle was significantly shorter (p less than 0.05) than the following cycle. In 16 of these 25 patients a second bleeding episode occurred 19.0 +/- 0.8 days after the luteinizing hormone surge. The total treatment cycle was significantly prolonged (p less than 0.05) when compared with the following cycle. In the group with a single bleeding episode, there was a significant decline in follicle-stimulating hormone, estradiol, and progesterone over the 48-hour sampling period, but there was no change in these values in the group with two bleeding episodes. These two groups could not be separated on the basis of RU 486 dose or serum levels. After the four higher doses, there was a dose-dependent rise in serum prolactin. There were no alterations in mean cortisol values with the three lower doses, but there was a significant increase at 24 and 48 hours after the higher doses. Serum levels of RU 486 were maximal between 1 and 4 hours and the half-life of serum RU 486 was determined to be 24 hours.  相似文献   
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