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51.
肠息肉发生的细胞和分子生物学研究进展 总被引:1,自引:0,他引:1
肠息肉是一类从黏膜表面突出到肠腔内的隆起状病变的临床诊断.在最近的研究中陆续证实,其发生和发展的原因和机制,是由于Bmprla,APC,SMAD4,PTEN,STK11等基强突变而使各种细胞信号分子通过影响BMP信号通路,PTEN信号通路及Wnt信号通路所组成的生长信号调控网络,造成β-catenin在肠干细胞中的过度积聚,使得肠干细胞功能紊乱,导致其自我更新、克隆增殖、分化和凋亡失去平衡的结果. 相似文献
52.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
53.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
54.
Zoe L. Hewett Kate L. Pumpa Caroline A. Smith Paul P. Fahey Birinder S. Cheema 《Journal of Science and Medicine in Sport》2018,21(4):352-357
Objectives
The purpose of this study was to investigate the effect of 16 weeks of Bikram yoga on perceived stress, self-efficacy and health related quality of life (HRQoL) in sedentary, stressed adults.Design
16 week, parallel-arm, randomised controlled trial with flexible dosing.Methods
Physically inactive, stressed adults (37.2 ± 10.8 years) were randomised to Bikram yoga (three to five classes per week) or control (no treatment) group for 16 weeks. Outcome measures, collected via self-report, included perceived stress, general self-efficacy, and HRQoL. Outcomes were assessed at baseline, midpoint and completion.Results
Individuals were randomised to the experimental (n = 29) or control group (n = 34). Average attendance in the experimental group was 27 ± 18 classes. Repeated measure analyses of variance (intention-to-treat) demonstrated significantly improved perceived stress (p = 0.003, partial η2 = 0.109), general self-efficacy (p = 0.034, partial η2 = 0.056), and the general health (p = 0.034, partial η2 = 0.058) and energy/fatigue (p = 0.019, partial η2 = 0.066) domains of HRQoL in the experimental group versus the control group. Attendance was significantly associated with reductions in perceived stress, and an increase in several domains of HRQoL.Conclusions
16 weeks of Bikram yoga significantly improved perceived stress, general self-efficacy and HRQoL in sedentary, stressed adults. Future research should consider ways to optimise adherence, and should investigate effects of Bikram yoga intervention in other populations at risk for stress-related illness.Trial registration
Australia New Zealand Clinical Trials Registry ACTRN12616000867493. Registered 04 July 2016. URL: http://www.anzctr.org.au/ACTRN12616000867493.aspx. 相似文献55.
56.
Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
57.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions. 相似文献
58.
Deficits in neuromuscular control of the trunk predict knee injury risk: a prospective biomechanical-epidemiologic study 总被引:3,自引:0,他引:3
Zazulak BT Hewett TE Reeves NP Goldberg B Cholewicki J 《The American journal of sports medicine》2007,35(7):1123-1130
BACKGROUND: Female athletes are at significantly greater risk of anterior cruciate ligament (ACL) injury than male athletes in the same high-risk sports. Decreased trunk (core) neuromuscular control may compromise dynamic knee stability. HYPOTHESES: (1) Increased trunk displacement after sudden force release would be associated with increased knee injury risk; (2) coronal (lateral), not sagittal, plane displacement would be the strongest predictor of knee ligament injury; (3) logistic regression of factors related to core stability would accurately predict knee, ligament, and ACL injury risk; and (4) the predictive value of these models would differ between genders. STUDY DESIGN: Cohort study (prognosis); Level of evidence, 2. METHODS: In this study, 277 collegiate athletes (140 female and 137 male) were prospectively tested for trunk displacement after a sudden force release. Analysis of variance and multivariate logistic regression identified predictors of risk in athletes who sustained knee injury. RESULTS: Twenty-five athletes (11 female and 14 male) sustained knee injuries over a 3-year period. Trunk displacement was greater in athletes with knee, ligament, and ACL injuries than in uninjured athletes (P < .05). Lateral displacement was the strongest predictor of ligament injury (P = .009). A logistic regression model, consisting of trunk displacements, proprioception, and history of low back pain, predicted knee ligament injury with 91% sensitivity and 68% specificity (P = .001). This model predicted knee, ligament, and ACL injury risk in female athletes with 84%, 89%, and 91% accuracy, but only history of low back pain was a significant predictor of knee ligament injury risk in male athletes. CONCLUSIONS: Factors related to core stability predicted risk of athletic knee, ligament, and ACL injuries with high sensitivity and moderate specificity in female, but not male, athletes. 相似文献
59.
A review of electromyographic activation levels, timing differences, and increased anterior cruciate ligament injury incidence in female athletes 下载免费PDF全文
Deficits in dynamic neuromuscular control of the knee may contribute to the higher incidence of anterior cruciate ligament (ACL) injury in female athletes. There is evidence that neuromuscular training alters muscle firing patterns, as it decreases landing forces, improves balance, and reduces ACL injury incidence in female athletes. The purpose of this review is to summarise the evidence for altered muscular activation and timing relative to ACL injury risk in female athletes. 相似文献
60.
Occlusion of varicoceles wih detachable balloons 总被引:1,自引:0,他引:1