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961.
Bacterial infection and biofilm formation on the surface of biliary stents is believed to be one of the main factors in stent occlusion. This study explored the role of the new reagent, bismuth dimercaprol, in preventing bacterial adherence and bacterial biofilm formation on the surface of biliary stents. Sterile porcine bile preparations, infected separately with Escherichia coli, Klebsiella pneumoniae, Enterobacter, and Enterococcus, were used as the perfusion media in an in vitro perfusion system. The bacterial growth in the media and the bacterial adherence on the surface of stents were tested when different concentrations of bismuth dimercaprol were used in the perfusion media. BisBAL (5 μ M) did not inhibit the growth of any of the tested bacterial species. It did, however, significantly decrease the amount of bacteria adhering to the surface of stents for all bacterial strains except Escherichia coli. Bismuth dimercaprol (20 μ M) significantly inhibited the growth of Escherichia coli, Klebsiella pneumoniae, and Enterobacter and, thereby, significantly decreased the amount of these bacteria adhering to the surface of stents. The unique bactericidal and anitbiofilm activities of bismuth thiols might contribute to delaying the process of biliary stent occlusion if the effective concentrations of bismuth thiols could be delivered to the target sites. The feasibility of this application of bismuth thiols deserves further investigation. 相似文献
962.
Kirman I Whelan RL Jain S Nielsen SE Seidelin JB Nielsen OH 《Digestive diseases and sciences》2005,50(4):780-784
Epithelial cell growth regulation has been reported to be altered in inflammatory bowel disease (IBD) patients. The cell growth regulatory factor, insulin-like growth factor binding protein 3 (IGFBP-3), may be partly responsible for this phenomenon. So far, IGFBP-3 levels have been assessed as values of total protein, which is a sum of bioactive intact 43- to 45-kDa protein and its inactive proteolytic cleavage fragments. We aimed to assess the levels of intact IGFBP-3 and its cleaving protease MMP-9 in IBD. Patients with IBD and controls were included. Total plasma IGFBP-3 concentration was measured in ELISA. Western blot analysis, which distinguishes between intact and cleaved IGFBP-3, was performed in order to determine the ratio of intact to total protein; this ratio was used to calculate the concentration of intact IGFBP-3. The profile of plasma proteases was evaluated in zymography and MMP-9 levels were determined in ELISA. The concentration of intact IGFBP-3 was significantly decreased in patients with moderate to severe IBD activity compared to those in remission or controls. Of note, a dramatic depletion of intact IGFBP-3 was found in 7.4% of patients with IBD. Zymography revealed that the dominant gelatinase was the pro-form of MMP-9. However, no differences in MMP-9 levels were noted between those with active disease and controls. The level of intact IGFBP-3 is decreased in IBD patients with moderate to severe disease activity. This decrease may be linked to altered IGFBP-3 production or to increased cleavage by proteases other than MMP-9. 相似文献
963.
Prolonged in utero meconium exposure impairs spatial learning in the adult rat : Central Prize Award
Sean C Blackwell Mordechai Hallak MD MPA John W Hotra BS Jerrie Refuerzo MD Robert J Sokol MD Yoram Sorokin MD 《American journal of obstetrics and gynecology》2004,190(6):1551-1555
Objective
The purpose of this study was to examine the effects of prolonged in utero meconium exposure on adult learning and memory, as measured by the Morris water maze.Study design
Timed pregnant Long-Evans rats were studied. On gestational day 20 (term, 21 days of gestation), laparotomy was performed, and each maternal animal received an injection of clear amniotic fluid or meconium-stained amniotic fluid into each gestational sac. The laparotomy incision was closed, and the animals received postoperative monitoring through delivery. On postnatal days 145 to 148, the offspring underwent Morris water maze testing. The mean (±SEM) for the latency time was reported for each day's trial and compared between groups.Results
There were significant differences between meconium-stained amniotic fluid group and clear amniotic fluid group in the mean time to platform on day 1 (82.7 ± 1.8 seconds vs 75.9 ± 3.0 seconds; P = .04), day 2 (60.5 ± 3.5 seconds vs 47. 8 ± 4.6 seconds; P = .03), and day 3 (56.5 ± 4.5 seconds vs 34.7 ± 4.4 seconds; P = .001). However, there were no differences on days 4 and 5. There were also no differences between recall and response learning trials that were done after a 12-day retention period.Conclusion
In the absence of hypoxia or infection, prolonged in utero meconium exposure is associated with a delay of spatial learning in the adult rat. 相似文献964.
Phyllis Kernoff PhD Molly BS Amy PhD Susannah Heyer PhD Patricia Bartholow PhD 《Women's health issues》2004,14(6):220-226
The present study was conducted to test the assumptions of a staging system of reproductive aging that was proposed at the Stages of Reproductive Aging Workshop (STRAW) in 2001. Using longitudinal data provided by 100 women over a period of 3-12 years, we asked whether midlife women move in a uniform progression from pre- to peri- to postmenopause, as refuted by earlier studies but proposed by the STRAW model, or whether they differ from this assumed pattern. Participants were recruited from the TREMIN Research Program on Women's Health, the oldest ongoing study of menstruation and women's health in the world. Eligibility criteria included reaching menopause during the course of the study and not using exogenous hormones. Participants provided annual self-reports of menopausal stage based on observations of their menstrual cycles ("regular," "changing," and "menopausal"). Findings revealed a lack of uniformity as women progressed toward menopause. From 8 to over 20 different perimenopausal stage patterns were observed, depending on the analysis. While the most common pattern was to progress from regular to changing to menopause, some women experienced menstrual bleeding after a year or more of amenorrhea, others flip-flopped between stages, and still others skipped directly from regular bleeding to menopause. We conclude that there is considerable variation in women's movement across menopausal status categories and urge researchers to accommodate such findings in their model building. 相似文献
965.
BS Duggal P Tarneja RK Sharma SK Rath RD Wadhwa VSM 《Medical Journal Armed Forces India》2004,60(1):28-30
Retrospective study of 121 cases of adnexal masses which were managed laparoscopically was carried out. The aim of study was to evaluate the safety and effectiveness of laparoscopic management of adnexal masses. In 120 cases, procedure was completed safely with minimum morbidity. In one case laparotomy had to be done to complete the procedure. In 76 cases cystectomy was done, 26 required salpingo-oophorectomy and 19 required only salpingectomy. Histologic evaluation revealed 30 functional cysts, 36 endometriotic cysts, 11 dermoids, 9 serous cystadenomas, 3 mucinous cystadenomas, 11 parovarian cysts, 19 cases of hydrosalpinx and 2 cases of tuberculosis.Key Words: Adnexal mass, Laparoscopy, Ovarian cyst 相似文献
966.
Patricia A. Hebda PhD ; Diana Whaley BS ; Hyung-Gyoon Kim PhD ; Alan Wells MD DSc 《Wound repair and regeneration》2003,11(5):373-379
Temporally controlled expression of genes in transgenic mice has advanced our understanding of many physiological processes. One of the more common modes of acutely altering gene levels involves the doxycycline-regulated "tet-on/tet-off" systems. There has been concern that the administration of doxycycline in itself might compromise many aspects of wound repair. Here we report that oral ad libitum administration of doxycycline (2 mg/ml in drinking water) to mice does not alter dermal or epidermal wound healing. The healing of both full- and partial-thickness skin wounds proceeded similarly regardless of doxycycline administration; in fact, collagen organization and tensile strength development appeared to accelerate in the presence of doxycycline. These data suggest that wound healing studies incorporating transgene expression can utilize tet-on/tet-off regulation of gene expression without interference from doxycycline. 相似文献
967.
STUDY DESIGN: In this cadaveric study, a computer-assisted image guidance system was tested for accuracy of thoracic pedicle screw placement. OBJECTIVES: Evaluate the system's accuracy for thoracic pedicle screw placement in vitro. SUMMARY OF BACKGROUND DATA: The effective use and reliability of pedicle screw instrumentation in providing short-segment stabilization and correction of deformity is well known in the lumbar spine. Pedicle screw placement in the thoracic spine is difficult because of the small dimensions of the thoracic pedicles and risk to the adjacent spinal cord and neurovascular structures. Investigators have shown the improved accuracy of computer-assisted lumbar pedicle screw placement; but the accuracy of computer-assisted thoracic pedicle screw placement, which is becoming more widely used, has not been shown. METHODS: In five human cadavers, 120 thoracic pedicle screws were placed with computer-assisted image guidance. The largest clinically feasible screw was used based on the cross-sectional dimensions of each pedicle. The accuracy was assessed by postoperative computed tomography and visual inspection. RESULTS: The overall pedicle cortex violation was 23 of 120 pedicles (19.2%). Nine violations (7.5%) were graded as major and 14 (11.7%) as minor. A marked and progressive learning curve was evident with the perforation rates that decreased from 37.5% in the first cadaver to 4.2% in the last two cadavers. CONCLUSIONS: Accurate thoracic pedicle screw placement is feasible with computer-assisted surgery. However, as with any other new surgical technology, the learning curve must be recognized and incorporated into the necessary fundamental knowledge and experience for these procedures. 相似文献
968.
Susan L. Greenspan MD Eric von Stetten PhD Sarah K. Emond BA Lisa Jones BS CNMT Robert A. Parker SCD 《Journal of clinical densitometry》2001,4(4):373-380
The presence of a vertebral fracture significantly increases the risk of future fracture, classifies a patient with "clinical" osteoporosis, and usually results in treatment for osteoporosis. However, the majority of vertebral fractures are silent, and lateral X-rays (the standard method for identification) are not routinely obtained. Instant vertebral assessment (IVA), a technology that utilizes dual X-ray absorptiometry (DXA), provides rapid assessment of vertebral fractures and is highly correlated with vertebral fractures, as assessed on standard lateral spine X-rays. To assess the role of IVA in patient management, we examined standard bone mineral density (BMD) of the spine, total hip, and femoral neck and spine IVA by DXA in 482 participants screened for an osteoporosis study, who had no previous knowledge of vertebral fractures. Using World Health Organization (WHO) guidelines, subjects were classified using BMD at the spine, total hip, femoral neck, or any combination of these central sites. In addition, we considered subjects as osteoporotic if they had vertebral fractures independent of low bone density. We found that vertebral fractures assessed by IVA were present in 18.3% of asymptomatic postmenopausal women recruited for this study. The sensitivity of BMD alone to diagnose osteoporosis based on either a vertebral fracture or low BMD using WHO criteria ranged from 40 to 74%. This means that between 26 and 60% of osteoporotic individuals could have potentially been missed. Furthermore, 11.0-18.7% of clinically osteoporotic individuals would have been classified as normal by BMD criteria alone. We conclude that IVA is a useful adjunct in the clinical identification of osteoporosis and may prevent mismanagement of osteoporotic patients. 相似文献
969.
Jeremy B. White MD Mathieu Barraja MS Tewodros Mengesha MS Sumit Bose BS Samaneh Ashktorab BA Ryan Bahn BS Ryan Vallance PhD William H. Lindsey MD FACS 《The Laryngoscope》2008,118(12):2107-2110
Background: Manipulation and suspension of the superficial musculoaponeurotic system (SMAS) is performed by 74% of rhytidectomy surgeons. Multiple variations in suture techniques are employed in this task, but they have never been evaluated for differences in their ability to withstand stress. Objective: To compare the biomechanical properties of two different suture techniques that are used in SMAS plications during rhytidectomy: a double‐layered running locking (DRL) stitch and multiple horizontal mattress stitches. Methods: Fourteen horizontal mattress plications, in rows of six sutures, and comparable lengths of 16 DRL stitch plications of pig skin samples, were stressed using a tensometer with grip displacement increasing at a constant rate of 0.5 cm/Min. The required force to cause plication failure was recorded for each sample at three suture break points. Results: There was no significant difference between the two groups in the force required to cause the initial suture failure. Unlike the horizontal mattress plication, an initial break seemed to cause minimal to no distortion of the DRL tissue plication. When results were normalized by the initial break forces to account for small variations in tissue properties, the force ratio required to cause a second suture break was significantly larger in the DRL group than in the horizontal mattress technique. This is evidenced by the average second to first break force ratios of 1.62 vs. 1.13 for the DRL and horizontal mattress stitches, respectively, with a P‐value of .60. The mean ratios of third to first break forces for the DRL and horizontal mattress groups were 2.08 and 0.91, respectively, with a P‐value of .08. Conclusion: The DRL stitch requires more force than the horizontal mattress stitch to cause significant failure of tissue plication. This technique may enable plastic surgeons to avoid early revision rhytidectomy due to suture failure, and to create a long‐lasting, youthful cosmetic result. 相似文献
970.
Mapping FACT-P and EORTC QLQ-C30 to Patient Health Status Measured by EQ-5D in Metastatic Hormone-Refractory Prostate Cancer Patients 总被引:2,自引:0,他引:2
Eric Q. Wu PhD Parvez Mulani MS CPhil Max H. Farrell BS Darryl Sleep MD MBBCh FCS 《Value in health》2007,10(5):408-414
OBJECTIVES: To construct and validate a prediction model of preference-adjusted health status (EQ-5D) for metastatic hormone-refractory prostate cancer (HRPCA) patients using cancer-specific health-related quality of life (HRQoL) measures. METHODS: Data were obtained from a multicenter, multinational observational study of metastatic HRPCA patients conducted during 2002 to 2004. In addition to clinical and resource utilization, preference-adjusted health status (EQ-5D) and HRQoL (Functional Assessment of Cancer Therapy-Prostate [FACT-P] and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire [EORTC QLQ-C30]) data were collected. Predictive validity of ordinary least square (OLS) and median regressions of various model specifications were tested using cross-validation samples. The selected specification was then further refined and tested for alternative model specifications and restrictions. RESULTS: OLS regression with both HRQoL measures as individual components and patient demographics was the best-performing model. It explained 58.2% of the observed EQ-5D variation in the validation sample. A model including only the prostate cancer-specific HRQoL measure, FACT-P, explained 53.5% of the observed EQ-5D variation. CONCLUSIONS: The models developed have good predictive validity. These algorithms enable researchers to translate cancer-specific HRQoL measures to preference-adjusted health status in metastatic HRPCA patients. The findings will help perform health status adjustments in cost-utility analyses. 相似文献