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41.
OBJECTIVE: To evaluate the association between endometriosis and the p53 polymorphism. DESIGN: Prospective study. SETTING: Department of gynecology and genetics in a medical center. PATIENT(S): Women with and without endometriosis. INTERVENTION(S): Women were categorized as having moderate or severe endometriosis (n = 118) or no endometriosis (n = 140). MAIN OUTCOME MEASURE(S): Polymerase chain reaction was used to detect p53 codon 72 polymorphisms (arginine homozygosity, heterozygosity, and proline homozygosity). Associations between endometriosis and p53 polymorphisms were evaluated. RESULT(S): The distributions of different p53 polymorphisms differed significantly between groups. The respective proportions of arginine homozygotes, heterozygotes, and proline homozygotes were 10.2%, 66.9%, and 22.9% in the group with endometriosis and 30.7%, 50%, and 19.3% in the group without endometriosis. CONCLUSION(S): Endometriosis is associated with p53 polymorphism. p53 arginine homozygotes have lower risk for endometriosis. Heterozygotes and proline homozygotes have higher risk for endometriosis.  相似文献   
42.
3-(p-Trifluoromethylphenoxy)-N-methyl-3-phenylpropylamine (Lilly 110140) competitively inhibited the uptake of serotonin (5-HT), norepinephrine (NE) and dopamine into synaptosomes of rat brain with Ki values of 5.5 x 10-minus8, 9.5 x 10-minus6 and 1.3 x 10-minus5 M, respectively. Aiming for a more effective inhibitor of 5-HT uptake, we found the trifluoromethyl group in the phenoxy ring was most favorable at the para-position and was better than other substituting groups including fluoro, chloro, methyl and methoxy groups. The N-demethylated (primary amine) and the N.N-diemthylated (tertiary amine) derivatives inhibited the uptake of monoamines with the same effectiveness as Lilly 110140 (a secondary amine). The uptake of 5-HT into synaptosomes was significantly inhibited 15 minutes after an intraperitoneal administration of Lilly 110140. The inhibition persisted for a 24-hour period. NE uptake in vitro maintained a normal rate during the entire time course. Lilly 110140 likewise had no effect on the in vitro and in vivo accumulation of 3-H-tryptophan in the brain. The effect of Lilly 110140 and the tricyclic drug, chlorimipramine, was compared. Although chlorimipramine inhibited the uptake of 5-HT into synaptosomes with same effectiveness as Lilly 110140 in vitro, it reduced the uptake of both 5-HT and NE in vivo. Chlorimipramine exerted its greatest inhibition on the two uptake processes in the 1st hour and none by the 4th hour. Unlike the tricyclic drugs, imipramine, chlorimipramine, desipramine and chlordesipramine, Lilly 110140 and its primary amine derivative did not block the in vivo uptake of NE into rat heart. The present study suggests that Lilly 110140 is a potent and selective inhibitor for uptake of 5-HT into synaptosomes of rat brain.  相似文献   
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STUDY OBJECTIVE: To compare results of a vaginal approach to colpotomy (type IA) and laparoscopic-assisted abdominal colpotomy (type ID) in performing a laparoscopic-assisted vaginal hysterectomy (LAVH). DESIGN: Prospective, randomized study (Canadian Task Force classification I). SETTING: Tertiary teaching hospital. PATIENTS: Five hundred forty-one women, 274 in group 1 (type 1D) and 267 in group 2 (type 1A). INTERVENTION: LAVH with follow-up for 3 months to 5 years. MEASUREMENTS AND MAIN RESULTS: There were no statistically significant differences in age, preoperative and postoperative hemoglobin values, or postoperative hospital stay between groups. Operating time and estimated blood loss were significantly reduced in group 2 (p <0.001 and <0.001, respectively). Women in group 1 had nine urinary tract injuries (3.28%), including eight cases of intraoperative bladder injury (2.91%) and one vesicovaginal fistula (0.36%), but no ureteral injury.The bladder injury rate in group 2 was 0.37%, which was significantly lower (p = 0.038). There were no significant differences in ureteral or bowel injuries, pelvic hematomas, or pelvic abscesses. CONCLUSION: LAVH type IA achieved better results than type ID in preventing bladder injury.  相似文献   
45.
INTRODUCTION: Academic writing for publication is competitive and demanding for researchers. For the novice English-as-a-second-language (ESL) researcher, the pressure to publish compounds the difficulties of mastering the English language. Very few studies have used ESL graduate and post-graduate students as academic writing research subjects. The purpose of this project was to assess the learning needs of ESL clinical investigators regarding academic writing for English scholarly publication. METHOD: A qualitative evaluation approach was used to examine the gap between the current and desired proficiency level for the academic writing of ESL clinical investigators. We considered the perspectives of seven ESL clinical investigators plus three mentors and three writing instructors. Semi-structured questions were asked. Field notes were organized using a field-work recording system. They were analyzed using the constant comparative method. RESULTS: ESL clinical investigators do not accurately perceive their writing deficiencies. They have little knowledge of criteria for academic writing and they are influenced by their prior English learning experiences in their home culture, which engender passive attitudes toward seeking appropriate writing resources. Adequate time is especially needed to develop successful writing skills. DISCUSSION: Four basic steps are recommended to guide program planners in developing ESL writing activities for professional learning: (1) recognize discrepancies, (2) establish clear standards and performance criteria for scholarly writing, (3) develop individual plans, and (4) organize long-term writing assistance.  相似文献   
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Ovarian hyperstimulation syndrome (OHSS), a life-threatening complication occurring in stimulated ovarian cycles, arises from treatment with gonadotropin for induction of follicular maturation in infertile women. Clinical characteristics of OHSS include ascites and pleural effusion induced by increased vascular permeability, where vascular endothelial growth factor (VEGF) was suspected to be the culprit. To test whether the effects of human CG (hCG) on the pathogenesis of OHSS were mediated through the VEGF produced by luteinized granulosa cells, we measured estradiol, VEGF, IGF-II levels in serum, and follicular fluid and analyzed their mRNA expression in luteinized granulosa cells obtained from 101 women (58 with OHSS and 43 controls) who underwent in vitro fertilization and embryo transfer. This study presents the first evidence that hCG up-regulated VEGF expression of granulosa cells in the OHSS, not the control groups, and that follicular VEGF worked through an autocrine mechanism using its kinase insert domain-containing receptor, not the fms-like tyrosine kinase receptor. We calculated total follicular production of VEGF, by multiplying follicular concentrations by follicular volumes, and verified that an increase in total follicular production of VEGF accounted for elevated serum levels of VEGF, which was associated with the development of OHSS. These findings demonstrate that through up-regulation of VEGF, hCG plays a significant role in the pathogenesis of OHSS.  相似文献   
48.
BACKGROUND: This study was designed to determine the extent and duration of contrast sensitivity (CS) loss after high sustained +Gz acceleration in a centrifuge. METHODS: The subjects were 12 healthy male flight surgeons between 20 and 22 (mean = 21.1) yr of age. The human centrifuge at the Aviation Physiology Research Laboratory in Tainan, Taiwan, was used to expose the subjects to an acceleration profile. Each subject experienced three centrifuge runs made up of one gradual onset and two rapid onset profiles. Contrast sensitivity (CS) was measured before, and at 5 min, 10 min, and 20 min for the right eye; and 7 min, 12 min, and 22 min for the left eye after the acceleration. Both eyes were measured with the right eye being tested first. RESULTS: There was a generalized depression of CS at 5-12 min for both eyes. The depression was more severe at low and medium frequencies (1.5, 3.0, 6.0 cycles per degree, cpd) than at a high spatial frequency (18.0 cpd). There was a significant decrease in CS of the right eye at 1.5 cpd (p < 0.05 between control and 5 min), and on the left eye at 3.0 cpd (p < 0.05 between control and 7 min, p < 0.05 between control and 12 min) and 6.0 cpd (p < 0.05 between control and 12 min). The CS loss was more obvious at 5-12 min for both eyes, and there was only partial recovery at 22 min after the acceleration. CONCLUSIONS: These results demonstrated that +Gz acceleration is associated with CS loss. The recovery time was greater than expected. Factors other than ocular blood flow may be involved in the prolonged CS loss.  相似文献   
49.
Screening for metals in urine is important because toxic levels of these elements are linked to disease. In the current study, the authors used differential pulse stripping voltammetry on a hanging mercury drop electrode for the simultaneous determination of cadmium, cobalt, lead, and nickel in the urine of 63 production and 63 quality control workers in a steel production plant, along with 63 matched normal controls. Urinary sampling is a noninvasive procedure, and in this study participants had good compliance. Metal levels for both the production and quality control workers were significantly higher than for controls. The results reveal the need for immediate improvements in workplace ventilation and industrial hygiene practices for this cohort.  相似文献   
50.
The purpose of our study was to evaluate the outcome, patterns of failure, and toxicity for patients with unresectable hepatocellular carcinoma (HCC) treated with radiotherapy, transcatheter arterial chemoembolization (TACE), or combined TACE and radiotherapy. Forty-two patients with unresectable HCC were treated with combined radiotherapy and TACE (TACE+RT group, 17 patients), radiotherapy alone (RT group, 9 patients), or with TACE alone (TACE group, 16 patients). Mean dose of radiation was 46.9 +/- 5.8 Gy in a daily fraction of 1.8 to 2 Gy, directed only to the cancer-involved areas of the liver. TACE was performed with a combination of Lipiodol, doxorubicin, cisplatin, and mitomycin C, followed by Gelfoam or Ivalon embolization. Tumor size was smaller in the TACE group (mean: 5.4 cm) compared with the TACE+RT group (8.6 cm) and the RT group (13.1 cm) (P = 0.0003). The median follow-up was 24 months in the TACE+RT group, 28 months in the RT group, and 23 months in the TACE group. Survival was significantly worse for patients treated with radiotherapy alone due to the selection bias of patients with more advanced disease and compromised condition in this group. In contrast, the TACE+RT and TACE groups had comparable survival (two-year rates: TACE+RT 58%, TACE 56%, P = 0.69). The local control rate for the treated tumors was similar in the TACE+RT and TACE groups (P = 0.11). The intrahepatic recurrence outside the treated tumors was common and similar between these two groups (P = 0.48). The extrahepatic progression-free survival was significantly shorter for patients in the TACE+RT group than in the TACE group (two-year rates: TACE+RT 36%, TACE 100%, P = 0.002). Seven patients died from complications of treatment. Local radiotherapy may be added to treat patients with unresectable HCC, and the control of progression of the treated tumors was promising even in patients with large hepatic tumors. Survival of patients with combined TACE and radiotherapy was similar to that with TACE as the only treatment, while a significant portion of the patients treated with radiotherapy developed extrahepatic metastasis.  相似文献   
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