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991.
992.
E. Ishmael Parsai Diana Shvydka Jun Kang Philip Chan David Pearson Faheem Ahmad 《Applied radiation and isotopes》2010,68(12):2174-2180
We assess the accuracy of ADAC Pinnacle3 commercial treatment planning system (TPS) in computation of isodose distributions for shaped electron fields. The assessment is based on comparison of dose profiles generated by TPS and a Monte Carlo model for different beam energies, applicator sizes, and percentages of field blocking. Dose differences of up to 14% are observed at the depth of maximum dose. These discrepancies, often ignored in clinical evaluations, are attributable to inadequate modeling of scatter from applicators and blocks by TPS. 相似文献
993.
Lorna A. Brudie Giorgia Gaia Sarfraz Ahmad Neil J. Finkler Glenn E. Bigsby IV Giselle B. Ghurani James E. Kendrick IV Joseph A. Rakowski Jessica H. Groton Robert W. Holloway 《Journal of robotic surgery》2012,6(4):317-322
We analyzed peri-operative outcomes of 80 patients who underwent robotic-assisted laparoscopic surgery and were diagnosed with stage IV endometriosis (revised American Society for Reproductive Medicine) between January 2007 and December 2010 at a tertiary gynecologic oncology referral center with a fellowship training program. Eligible women had a combination of one or more factors: pelvic mass, sub-acute or chronic pelvic pain, dysmenorrhea, dyspareunia, elevated serum CA-125, diagnosed with stage IV endometriosis at surgery with robotic-assisted gynecologic procedures using the da Vinci? Surgical System. The mean age was 43.7?±?7.0?years, body mass index 27.5?±?7.4?kg/m2, and 23 (28.9%) patients had prior endometriosis surgery. Presenting symptoms included: chronic pelvic pain (48.8%), dysmenorrhea (40.3%), and dyspareunia (33.8%). Sixty-nine (86%) patients had pelvic masses (43 unilateral and 26 bilateral). Thirty-seven (46.3%) had elevated CA-125 levels (mean 97.9?±?71.6 U/ml). Forty-eight (60%) underwent robotic-assisted laparoscopic hysterectomy (RALH)/bilateral salpingo-oophorectomy (BSO), 9 (11.3%) RALH/unilateral salpingo-oophorectomy (USO), 5 (6.3%) modified radical hysterectomy, and 10 (13%) USO or BSO only. Four (5%) had ovarian cystectomies with excision of endometriotic implants. Three (3.8%) underwent appendectomy and no patient required bowel resection. Four (5%) patients required conversion to laparotomy during the first 15 cases of this series [dense adhesions (3) and ureteral injury (1)]. Mean operative time was 115?±?46?min, blood loss 88?±?67?ml, and length of stay 1.0?±?0.4?days. There were four (5%) complications (ureteral injury, cuff abscess, cuff hematoma, re-admission for nausea and vomiting secondary to narcotics) and no transfusions. One (1.3%) patient underwent a second surgery for pain (dyspareunia). Robotic-assisted surgery for stage IV endometriosis resulted in excellent pain relief, with few laparotomy conversions or complications during a robotic learning-curve experience. 相似文献
994.
Lily C. Uihlein M.D. J.D. Marilyn G. Liang M.D. Steven J. Fishman M.D. Ahmad I. Alomari M.D. John B. Mulliken M.D. 《Pediatric dermatology》2013,30(5):541-548
Regional capillary malformation of a lower extremity is associated with the overgrowth of bone or soft tissue in several disorders, most commonly Klippel–Trenaunay syndrome and Parkes Weber syndrome. We have observed a subset of patients with a capillary malformation of the leg, minor growth disturbance, and prominent veins. The objective of the current study is to describe a series of patients with regional capillary malformation of the lower extremity in association with phlebectasia. This is a retrospective series of 17 patients diagnosed with capillary‐venous malformation of the lower extremity. We excluded patients with clinical or radiographic evidence of lymphatic or arteriovenous malformation. Age, presentation, associated features, radiographic findings, and management were documented. In most patients the capillary malformation covered a large area without sharply demarcated borders. Four patients had one or more discrete, well‐defined capillary stains involving less than 5% of the total surface area of the affected lower limb. Prominent veins were most common in the popliteal fossa and on the knee and dorsal foot. Approximately two‐thirds of patients had a leg length discrepancy, with the affected leg being longer (n = 6) or shorter (n = 4); in many the affected leg was also slightly larger (n = 8) or smaller (n = 4) in girth. Radiographic imaging showed dilatation of superficial (n = 16), muscular (n = 9), and deep veins (n = 6). We characterize a subset of patients with regional capillary‐venous malformation of the lower extremity with prominent veins and minor hypotrophy/hypertrophy that differs from Klippel–Trenaunay syndrome (capillary‐lymphatic‐venous malformation) but belongs at the minor end of the spectrum of vascular disorders with overgrowth. 相似文献
995.
Shaymaa Abdalwahed Abdulameer Syed Azhar Syed Sulaiman Mohamed Azmi Ahmad Hassali Karuppiah Subramaniam Mohanad Naji Sahib 《Journal of community health》2013,38(1):95-105
Osteoporosis is a major growing public health problem and it is clear that much needs to be done to bridge the gap between patients and practitioners. However, the educator must have a valid and reliable tool to evaluate the effectiveness of the teaching and learning that are done. Osteoporosis Knowledge Tool (OKT) provides an important strategy for healthcare professionals to start early intervention for patients who are at risk of osteoporosis. The aims of this study were to translate and examine the psychometric properties of the Malaysian version of the Osteoporosis Knowledge Tool (OKT-M) among 250 type 2 diabetes patients and to assess factors that affect diabetic patients’ osteoporosis knowledge. The OKT English version was translated and validated using the internationally accepted and recommended methodology. The sensitivity and specificity of OKT-M was calculated using receiver operating characteristic curve analysis. The face and content validity showed acceptable results. Internal consistency, test–retest reliability, mean difficulty factor and discriminatory power values were 0.72, 0.83, 0.47 ± 0.16 and 0.96, respectively. The cut-off point of the OKT-M to predict osteoporosis/osteopenia was 14 with optimal sensitivity (84.1 %) and specificity (85.5 %). Regression analysis revealed that health belief, self-efficacy and some demographic data had an impact on the OKT-M. The findings of this validation study indicate that the OKT-M is a reliable and valid tool with good psychometric properties in the Malaysian setting. The OKT-M is an appropriate tool for application in clinical setting to identify patients need for a bone health-promoting intervention regarding lifestyle behaviour changes. 相似文献
996.
W. Ahmad A.N. Kanatas D.A. Mitchell 《International journal of oral and maxillofacial surgery》2010,39(6):620-622
Parathyroid carcinoma is a rare malignancy and is a cause of primary hyperparathyroidism in less than 1% of cases. The authors present a case in which a lesion, radiologically suggestive of a carotid body tumour, but with the peroperative appearance of a vagal schwannoma had the definitive pathological diagnosis of parathyroid carcinoma. Surgeons should be aware of unexpected malignant lesions involving the parathyroid glands. 相似文献
997.
998.
Stem cells: new opportunities to treat eye diseases. 总被引:6,自引:0,他引:6
I Ahmad 《Investigative ophthalmology & visual science》2001,42(12):2743-2748
999.
1000.
L C Platanias S Uddin E Bruno M Korkmaz S Ahmad Y Alsayed D Van Den Berg B J Druker A Wickrema R Hoffman 《Experimental hematology》1999,27(8):1315-1321
Interferons are potent regulators of normal and malignant hematopoietic cell proliferation in vitro and in vivo, but the signaling mechanisms by which they exhibit their growth inhibitory effects are unknown. We have recently shown that CrkL is engaged in Type I IFN signaling, as shown by its rapid tyrosine phosphorylation during engagement of the Type I IFN receptor. In the present study, we provide evidence that the related CrkII protein is also rapidly phosphorylated on tyrosine during treatment of U-266 and Daudi cells with IFNalpha or IFNbeta. We also show that both members of the Crk-family, CrkL and CrkII, are phosphorylated in an interferon-dependent manner in primary hematopoietic progenitors. Furthermore, inhibition of CrkL or CrkII protein expression by antisense oligonucleotides, reverses the inhibitory effects of IFNalpha or IFNgamma on the proliferation of normal bone marrow progenitor cells (colony forming units-granulocytic/monocytic [CFU-GM] and burst-forming units-erythroid [BFU-E]). Thus, both CrkL and CrkII are engaged in a signaling pathway (s) that mediates interferon-regulated inhibition of hematopoietic cell proliferation. 相似文献