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71.
To identify the predictive factors for testicular sperm extraction (TESE)
and to understand the pathology associated with TESE, we carried out a
prospective study in 40 consecutive men with azoospermia due to primary
gonadal failure. The main outcome measure was the retrieval of at least one
testicular spermatozoon. Endocrine and biophysical profiles, testicular
histology, Johnsen score and testicular spermatids were used as predictors
of sperm extraction. Spermatogenesis was quantified with the Johnsen score.
A variable pattern of spermatogenesis was common, being present in 20 (50%)
patients. Visualisation of testicular spermatids on testicular histology
showed a strong association with TESE (P < 0.0001). Statistically
significant differences were detected in plasma follicle stimulating
hormone (FSH) and testicular volume between patients who had
hypospermatogenesis and Sertoli cell-only or maturation arrest. There were
no significant differences in Johnsen score, biophysical and endocrine
profiles between the groups with successful and failed TESE. However, a
statistically significant trend occurred with changes in histological
pattern [chi2 for trend, P = 0.001; Pearson's coefficient (r) = 0.6],
Johnsen score (P = 0.022; r = 0.5), testicular volume (P = 0.01; r = 0.5)
and plasma FSH concentrations (P = 0.044; r = 0.4), albeit to a limited
degree. Difference in the interpretation of histological patterns with
different assessors was observed. The type of occupation or risk factors
for azoospermia showed no association with testicular pathology or TESE.
Variable histological patterns in different tubules in the same individual
may explain the poor correlation of TESE with endocrine and biophysical
profiles, Johnsen score and histological pattern. Differences in the amount
of tissue used for TESE and histopathology, and misinterpretation of
testicular histology rather than failure to quantify spermatogenesis may
explain the poor correlation between histological patterns and TESE.
Testicular spermatids predicted TESE. However, considerable overlap in
values means that no single variable can provide a perfect discrimination
between the groups with successful and failed TESE.
相似文献
72.
Two modes of embryo transfer, uterine and tubal, were compared following
natural cycle in-vitro fertilization (IVF). Only patients with patent
Fallopian tubes were included in the study. Tubal embryo transfer was
performed by retrograde tubal cannulation without analgesia on an
outpatient basis. Tubal transfer conferred no benefit compared with uterine
transfer in male factor infertility with positive fertilization (pregnancy
rates of 15.8% in both groups). Although tubal embryo transfer in the
patients with unexplained infertility improved the pregnancy rates from
7.8% in uterine transfer (5/64) to 17.6% in the tubal transfer group
(13/74), this improvement was not statistically significant.
相似文献
73.
Implantable microelectromechanical sensors for diagnostic monitoring and post‐surgical prediction of bone fracture healing 下载免费PDF全文
Kirk C. McGilvray Emre Unal Kevin L. Troyer Brandon G. Santoni Ross H. Palmer Jeremiah T. Easley Hilmi Volkan Demir Christian M. Puttlitz 《Journal of orthopaedic research》2015,33(10):1439-1446
The relationship between modern clinical diagnostic data, such as from radiographs or computed tomography, and the temporal biomechanical integrity of bone fracture healing has not been well‐established. A diagnostic tool that could quantitatively describe the biomechanical stability of the fracture site in order to predict the course of healing would represent a paradigm shift in the way fracture healing is evaluated. This paper describes the development and evaluation of a wireless, biocompatible, implantable, microelectromechanical system (bioMEMS) sensor, and its implementation in a large animal (ovine) model, that utilized both normal and delayed healing variants. The in vivo data indicated that the bioMEMS sensor was capable of detecting statistically significant differences (p‐value <0.04) between the two fracture healing groups as early as 21 days post‐fracture. In addition, post‐sacrifice micro‐computed tomography, and histology data demonstrated that the two model variants represented significantly different fracture healing outcomes, providing explicit supporting evidence that the sensor has the ability to predict differential healing cascades. These data verify that the bioMEMS sensor can be used as a diagnostic tool for detecting the in vivo course of fracture healing in the acute post‐treatment period. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1439–1446, 2015. 相似文献
74.
Trevor W. Reichman Helena Katchman Tomohiro Tanaka Paul D. Greig Ian D. McGilvray Mark S. Cattral Eberhard L. Renner Markus Selzner Anand Ghanekar Gary Levy David R. Grant 《Transplant international》2013,26(8):780-787
Informed consent for living donor liver transplantation (LDLT) requires that patients are provided with accurate information on the relative benefits and risks of this procedure compared with deceased donor liver transplantation (DDLT). There is strong evidence to suggest that LDLT facilitates timely transplantation to patients; however, information on the relative morbidity and death risks after LDLT as compared with DDLT is limited. A matched cohort comparison was performed matching recipients for age, MELD, date of transplant, gender, primary diagnosis, and recipient surgeon. A total of 145 LDLT were matched with 145 DDLT. LDLT had a higher overall rate of perioperative surgical complications (P = 0.009). Most of this difference was caused by a higher rate of biliary complications. However, the complications that occurred in the DDLT group tended to be more serious (P = 0.037), and these complications were strongly associated with graft loss in multivariate analysis. The 3‐ and 5‐year graft and patient survivals were similar. In conclusion, DDLT and LDLT have different complication profiles, but comparable hospital stays and survival rates. In areas of deceased donor organ shortages, LDLT offers an excellent alternative to DDLT because it facilitates access to a liver transplant without compromising short‐ or medium‐term recipient outcomes. 相似文献
75.
Ryohei?Takada Tetsuya?JinnoEmail authorView authors OrcID profile Kazumasa?Miyatake Yuki?Yamauchi Daisuke?Koga Kazuyoshi?Yagishita Atsushi?Okawa 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2018,28(4):621-625
Purpose
The purpose of this study is to clarify morphological changes of acetabular subchondral bone cyst after total hip arthroplasty for osteoarthritis secondary to developmental dysplasia of the hip.Methods
Two hundred and sixty-one primary cementless total hip arthroplasties of 208 patients, 18 males, 190 females, were retrospectively reviewed. Morphological changes of subchondral bone cyst were evaluated by computed tomography (CT). The mean cross-sectional area of the cyst from CT scans at 3 months postoperatively and after 7–10 years (average 8.4 years) were compared.Results
Acetabular subchondral bone cysts were found in 49.0% of all cases in preoperative CT scans. There was no cyst which was newly recognized in CT scan performed after postoperative 7–10 years. All the cross-sectional areas of the cysts evaluated in this study were reduced postoperatively.Conclusions
This study revealed that acetabular subchondral bone cysts do not increase or expand after total hip arthroplasty and indicated that the longitudinal morphological change of acetabular bone cysts in patients of developmental dysplasia of the hip do not influence long-term implant fixation in total hip arthroplasty.76.
Jeremiah Easley Christian M. Puttlitz Howard Seim Nicole Ramo Celeste Abjornson Frank P. Cammisa Kirk C. McGilvray 《The spine journal》2018,18(12):2302-2315
BACKGROUND CONTEXT
Screw loosening is a prevalent failure mode in orthopedic hardware, particularly in osteoporotic bone or revision procedures where the screw-bone engagement is limited.PURPOSE
The objective of this study was to evaluate the efficacy of a novel screw retention technology (SRT) in an ovine lumbar fusion model.STUDY DESIGN/SETTING
This was a biomechanical, radiographic, and histologic study utilizing an ovine lumbar spine model.METHODS
: In total, 54 (n=54) sheep lumbar spines (L2–L3) underwent posterior lumbar fusion (PLF) via pedicle screw fixation, connecting rod, and bone graft. Following three experimental variants were investigated: positive control (ideal clinical scenario), negative control (simulation of compromised screw holes), and SRT treatments. Biomechanical and histologic analyses of the functional spinal unit (FSU) were determined as a function of healing time (0, 3, and 12 months postoperative).RESULTS
Screw pull-out, screw break-out, and FSU stability of the SRT treatments were generally equivalent to the positive control group and considerably better than the negative control group. Histomorphology of the SRT treatment screw region of interest (ROI) observed an increase in bone percentage and decrease in void space during healing, consistent with ingrowth at the implant interface. The PLF ROI observed similar bone percentage throughout healing between the SRT treatment and positive control. Less bone formation was observed for the negative control.CONCLUSIONS
The results of this study demonstrate that the SRT improved screw retention and afforded effective FSU stabilization to achieve solid fusion in an otherwise compromised fixation scenario in a large animal model. 相似文献77.
Jonghun J. Lee BSc Peter T. W. Kim MD MSc FRCSC Sandra Fischer MD FRCPC Scott Fung MD FRCPC Steven Gallinger MD MSc FRCSC Ian McGilvray MD PhD FRCSC Carol-anne Moulton MD PhD FRCSC Alice C. Wei MD MSc FRCSC Paul D. Greig MD FRCSC Sean P. Cleary MD MSc MPH FRCSC 《Annals of surgical oncology》2014,21(8):2708-2716
Background
Hepatitis B (HBV) and hepatitis C (HCV) are well-recognized risk factors for hepatocellular carcinoma (HCC). The characteristics and clinical outcomes of HCC arising from these conditions may differ. This study was conducted to compare the outcomes of HCC associated with HBV and HCV after liver resection.Methods
Of 386 liver resections for HCC performed between July 1992 and April 2011, 181 patients had HBV and 74 patients had HCV. Patients with HBV/HCV coinfections (n = 20), non-HBV/HCV etiology (n = 94), and postoperative death within 3 months (n = 17) were excluded. Patient, tumor characteristics, and perioperative and oncologic outcomes were compared between patients with HBV and HCV.Results
The patients with HBV had better overall survival (OS) than patients with HCV (68 vs. 59 months, p = 0.03); however, there was no difference in recurrence-free survival (RFS) between the groups (44 vs. 45 months, p = 0.1). The factors predictive of OS based on multivariate analyses included: vascular invasion [p < 0.01, hazard ratio (HR) = 3.4], Child-Pugh Score (p < 0.01, HR = 4.8), and underlying liver disease (HCV vs HBV) (p = 0.01, HR = 1.9). Vascular invasion and tumor number (p < 0.01, HR = 2.3 and p < 0.01, HR = 2.1) were independent predictors of RFS.Conclusions
OS but not RFS after liver resection for HCC is better in patients with HBV than HCV. This survival advantage for HBV patients may be due to differences in tumor biology and outcomes after disease recurrence. 相似文献78.
Kirk C. McGilvray Erik I. Waldorff Jeremiah Easley Howard B. Seim Nianli Zhang Raymond J. Linovitz James T. Ryaby Christian M. Puttlitz 《The spine journal》2017,17(12):1907-1916
Background Context
The most commonly used materials used for interbody cages are titanium metal and polymer polyetheretherketone (PEEK). Both of these materials have demonstrated good biocompatibility. A major disadvantage associated with solid titanium cages is their radiopacity, limiting the postoperative monitoring of spinal fusion via standard imaging modalities. However, PEEK is radiolucent, allowing for a temporal assessment of the fusion mass by clinicians. On the other hand, PEEK is hydrophobic, which can limit bony ingrowth. Although both PEEK and titanium have demonstrated clinical success in obtaining a solid spinal fusion, innovations are being developed to improve fusion rates and to create stronger constructs using hybrid additive manufacturing approaches by incorporating both materials into a single interbody device.Purpose
The purpose of this study was to examine the interbody fusion characteristic of a PEEK Titanium Composite (PTC) cage for use in lumbar fusion.Study Design/Setting
Thirty-four mature female sheep underwent two-level (L2–L3 and L4–L5) interbody fusion using either a PEEK or a PTC cage (one of each per animal). Animals were sacrificed at 0, 8, 12, and 18 weeks post surgery.Materials and Methods
Post sacrifice, each surgically treated functional spinal unit underwent non-destructive kinematic testing, microcomputed tomography scanning, and histomorphometric analyses.Results
Relative to the standard PEEK cages, the PTC constructs demonstrated significant reductions in ranges of motion and a significant increase in stiffness. These biomechanical findings were reinforced by the presence of significantly more bone at the fusion site as well as ingrowth into the porous end plates.Conclusions
Overall, the results indicate that PTC interbody devices could potentially lead to a more robust intervertebral fusion relative to a standard PEEK device in a clinical setting. 相似文献79.
Biliary Strictures in 130 Consecutive Right Lobe Living Donor Liver Transplant Recipients: Results of a Western Center 总被引:4,自引:0,他引:4
S. A. Shah D. R. Grant I. D. McGilvray P. D. Greig M. Selzner L. B. Lilly N. Girgrah G. A. Levy M. S. Cattral 《American journal of transplantation》2007,7(1):161-167
Biliary strictures remain the most challenging aspect of adult right lobe living donor liver transplantation (RLDLT). Between 04/2000 and 10/2005, 130 consecutive RLDLTs were performed in our center and followed prospectively. Median follow-up was 23 months (range 3-67) and 1-year graft and patient survival was 85% and 87%, respectively. Overall incidence of biliary leaks (n = 19) or strictures (n = 22) was 32% (41/128) in 33 patients (26%). A duct-to-duct (D-D) or Roux-en-Y (R-Y) anastomosis were performed equally (n = 64 each) with no difference in stricture rate (p = 0.31). The use of ductoplasty increased the number of grafts with a single duct for anastomosis and reduced the biliary complication rate compared to grafts >/=2 ducts (17% vs. 46%; p = 0.02). Independent risk factors for strictures included older donor age and previous history of a bile leak. All strictures were managed nonsurgically initially but four patients ultimately required conversion from D-D to R-Y. Ninety-six percent (123/128) of patients are currently free of any biliary complications. D-D anastomosis is safe after RLDLT and provides access for future endoscopic therapy in cases of leak or stricture. When presented with multiple bile ducts, ductoplasty should be considered to reduce the potential chance of stricture. 相似文献
80.
S. A. Shah G. A. Levy P. D. Greig R. Smith I. D. McGilvray L. B. Lilly N. Girgrah M. S. Cattral D. R. Grant 《American journal of transplantation》2007,7(4):998-1002
Right lobe living donor liver transplantation (RLDLT) is not yet a fully accepted therapy for patients with end-stage liver failure in the Western hemisphere because of concerns about donor safety and inferior recipient outcomes. An outcome analysis from the time of listing for all adult patients who were listed for liver transplantation (LT) at our center was performed. From 2000 to 2006, 1091 patients were listed for LT. One hundred fifty-four patients (LRD; 14%) had suitable live donors and 153 (99%) underwent RLDLT. Of the remaining patients (DD/Waiting List; n = 937), 350 underwent deceased donor liver transplant (DDLT); 312 died or dropped off the waiting list; and 275 were still waiting at the time of this analysis. The LRD group had shorter mean waiting times (6.0 months vs. 9.8 months; p < 0.001). Although medical model for end-stage liver disease (MELD) scores were similar at the time of listing, MELD scores at LT were significantly higher in the DD/Waiting List group (15.4 vs. 19.5; p = 0.002). Patients in Group 1 had a survival advantage with RLDLT from the time of listing (1-year survival 90% vs. 80%; p < 0.001). To our knowledge, this is the first report to document a survival advantage at time of listing for RLDLT over DDLT. 相似文献