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991.
Mohamed A. Bedaiwy Mohamed Y. Abdel Rahman Mark Chapman Heidi Frasure Sangeeta Mahajan Vivian E. von Gruenigen William Hurd Kristine Zanotti 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2013,17(1):95-99
Objectives:
The primary objective was to examine the safety and feasibility of robotic-assisted laparoscopy in a cohort of women treated surgically for stage III and IV endometriosis. The secondary objective was to explore whether the stage of endometriosis affected surgical outcome.Methods:
In this cohort study, 43 women with severe endometriosis were treated with robot-assisted laparoscopic hysterectomy with unilateral or bilateral salpingo-oophorectomy for stage III (n = 19) or stage IV (n = 24) disease.Results:
Histopathologic evaluation confirmed endometriosis in all patients, and fibroids were also shown in 12 patients. The median actual operative time was 145 min (range, 67–325 min), and the median blood loss was 100 mL (range, 20–400 mL). All but one of the procedures were completed successfully robotically. The length of hospital stay was 1 d for 95% of patients (41 of 43), and 2 patients had prolonged stays of 4 d and 5 d, respectively. One patient was readmitted for a vaginal cuff abscess; this represented the only complication identified in this series.Conclusions:
Robot-assisted laparoscopic surgery appears to be a reasonably safe and feasible method for the definitive surgical management of women with severe endometriosis. 相似文献992.
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994.
Brian D. Hayes BMedSc MB FRCPath Caroline Brodie MB FRCPath Ann O'Doherty MB FRCR Cecily M. Quinn MD FRCPath 《The breast journal》2013,19(3):319-324
Mammographic calcification is an important radiologic feature of early breast carcinoma whose index of suspicion for malignancy may be reported by a five‐tier R‐category system. This study aims to describe the histologic diagnoses underlying screen‐detected mammographic calcifications using both digital and screen‐film mammography, and to correlate these findings with radiologic R‐categories. Patients attending the Merrion Breast Screening Unit in Dublin between 2000 and 2011 were identified, who underwent needle‐core biopsy for assessment of mammographic calcifications without associated mass or architectural distortion. Radiologic R‐category was correlated with biopsy and excision histology reports. A total of 776 cases of calcification were identified, involving 769 individual patients. The radiologic R‐categories were as follows: R3 513 (66.1%), R4 192 (24.7%), R5 71 (9.1%). The positive predictive values for malignancy were R3 32.6%, R4 69.8%, R5 95.8%. Several histologic features of DCIS were associated with R5 rather than R3 radiology: high nuclear grade, solid or cribriform architecture, necrosis, periductal inflammation or fibrosis, and associated microinvasive or invasive carcinoma. Mammographic lesions and histologic whole and invasive tumors increased in size from R3 to R5. Radiologic size of calcifications correlated with whole (but not invasive) tumor size, although it tended to underestimate it by several millimeters. Digital‐detected calcifications were more likely than screen‐film detected to be categorized as R3 and less likely R4 or R5, and there was no significant difference in positive predictive value between the two imaging techniques in any R‐category. In conclusion, histologic features of DCIS, in particular those associated with high grade, are associated with R5 radiology. There is no significant difference in positive predictive value for malignancy in any R‐category between digital and screen‐film mammography. 相似文献
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997.
Thord von Schewelov Lennart Sanzén Ingemar Önsten Åke Carlsson 《Acta orthopaedica》2013,84(3):283-294
Background?The purposes of this study were (1) to evaluate the wear pattern of the hydroxyapatite-coated “Dual Radius” Omnifit cup, (2) to investigate whether wear is correlated to any demographic or prosthesis-related factors, and (3) to describe micromotion of both the cup and the stem.Patients and methods?154 hips were implanted between 1990 and 1996 and followed for an average of 6 years. Wear was measured according to the “Charnley-duo” method and, in 79 hips, with radiostereometry (RSA). RSA was also used to evaluate micromotion. We analyzed the femoral heads using scanning electron microscopy, energy dispersive X-ray spectroscopy and an atomic force microscope.Result?66 cups were revised and had a mean annual wear of 0.32?mm compared to 0.12?mm in hips not revised. Osteolytic processes were observed in 35 hips but at revision osteolysis was present in 51 cases. 43/66 sockets were loose. Micromotion evaluated by RSA, weight, age, side, size of cup, screws, polyethylene thickness or shelf-life of the polyethylene did not correlate to wear, whereas male gender did.Interpretation?It is still unclear why about half of our cases had an abnormal wear rate. Annual wear exceeding 0.2?mm is prognostic of late failure and should be considered a warning sign. 相似文献
998.
Åke Carlsson Anders Björkman Karin Ringsberg Thord von Schewelov 《Acta orthopaedica》2013,84(4):389-396
Between 1993 and 2001, we replaced 22 hips in 16 patients with high dislocation of the hip. All but 1 case was due to congenital dislocation. In all cases the femur was osteotomized below the lesser trochanter and a straight uncemented stem inserted in the medullary canal. The acetabular prostheses were inserted at the site of the original acetabulum, usually after augmenting the acetabular rim by using the medial half of the resected proximal femur. The lateral part of the proximal femur with the intact attachment of the gluteus medius muscle was transposed and fixed to the femoral diaphysis thereby restoring direction of muscle pull. The HHS score increased from a median value of 42 points preoperatively to a median of 86 points after median 25 months of follow-up. Limp, which before surgery was severe in all cases, was less marked or had disappeared at follow-up. The legs had been lengthened median 2.5 (1.0–4.5) cm. No postoperative infections occurred. Palsy or loss of sensory function was not observed in any patient. Dislocation was the commonest complication. It occurred in 3 hips, 2 of which had to be revised to ensure stability. 相似文献
999.
Roland Pusch Hans‐Joachim Wagner Gerhard von der Emde Jacob Engelmann 《The Journal of comparative neurology》2013,521(17):4075-4093
The retina of the weakly electric fish Gnathonemus petersii is a so‐called grouped retina where photoreceptors are bundled. These bundles are regarded as functional units and this type of retinal specialization is uniquely found in teleosts. To understand how this anatomical organization influences visual information processing we investigated the morphology and distribution of retinal ganglion cells (GCs) and the response properties of retinal afferents terminating in the major retinorecipient area, the optic tectum. GCs were classified based on their dendritic morphology (dendritic field diameters <90–100 μm: narrow‐field GCs; 110–280 μm: widefield GCs; >280 μm: giant GCs). Within these classes subtypes were distinguished based on the ramification patterns of the dendrites in the sublaminae of the inner plexiform layer. Properties of presumed optic nerve terminals were investigated in the optic tectum using extracellular recordings. Physiological classes could be observed based on their response to visual stimuli (on; off; on‐off, and fast units). Receptive field sizes and spatiotemporal properties were classified and the topographical representation of the visual space was mapped in the tectum. Gratings of low spatial frequencies were best responded to and followed up to high temporal frequencies (>30 Hz). Most of the recorded units were directionally selective. No evidence of distorted topographies in the tectum was found, i.e., no overrepresentation of the retina was seen in the tectum opticum. The grouped retina of G. petersii seems to be optimized for the detection of large, fast objects in an environment of low optical quality. J. Comp. Neurol. 521:4075–4093, 2013. © 2013 Wiley Periodicals, Inc. 相似文献