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81.

Purpose

This study evaluated the accuracy of MR sequences [T2-, diffusion-weighted, and dynamic contrast-enhanced (T2WI, DWI, and DCE) imaging] at 3T, based on the European Society of Urogenital Radiology (ESUR) scoring system [Prostate Imaging Reporting and Data System (PI-RADS)] using MR-guided in-bore prostate biopsies as reference standard.

Methods

In 235 consecutive patients [aged 65.7?±?7.9 years; median prostate-specific antigen (PSA) 8 ng/ml] with multiparametric prostate MRI (mp-MRI), 566 lesions were scored according to PI-RADS. Histology of all lesions was obtained by targeted MR-guided in-bore biopsy.

Results

In 200 lesions, biopsy revealed prostate cancer (PCa). The area under the curve (AUC) for cancer detection was 0.70 (T2WI), 0.80 (DWI), and 0.74 (DCE). A combination of T2WI + DWI, T2WI + DCE, and DWI + DCE achieved an AUC of 0.81, 0.78, and 0.79. A summed PI-RADS score of T2WI + DWI + DCE achieved an AUC of 0.81. For higher grade PCa (primary Gleason pattern?≥?4), the AUC was 0.85 for T2WI + DWI, 0.84 for T2WI + DCE, 0.86 for DWI + DCE, and 0.87 for T2WI + DWI + DCE. The AUC for T2WI + DWI + DCE for transitional-zone PCa was 0.73, and for the peripheral zone 0.88. Regarding higher-grade PCa, AUC for transitional-zone PCa was 0.88, and for peripheral zone 0.96.

Conclusion

The combination of T2WI + DWI + DCE achieved the highest test accuracy, especially in patients with higher-grade PCa. The use of ≤2 MR sequences led to lower AUC in higher-grade and peripheral-zone cancers.

Key Points

? T2WI + DWI + DCE achieved the highest accuracy in patients with higher grade PCa ? T2WI + DWI + DCE was more accurate for peripheral- than for transitional-zone PCa ? DCE increased PCa detection accuracy in the peripheral zone ? DWI was the leading sequence in the transitional zone  相似文献   
82.

Purpose

This study was designed to determine the effectiveness of percutaneous balloon dilation and long-term drainage of postoperative benign biliary strictures.

Methods

Medical records of patients with postoperative benign biliary strictures, in whom percutaneous transhepatic biliary drainage (PTBD) and balloon dilation was performed between January 1999 and December 2011, were retrospectively reviewed. PTBD and balloon dilation (4–10 mm) were followed by placement of internal-external biliary drainage catheters (8.5–12 F). Patients were scheduled for elective tube changes, if necessary combined with repeated balloon dilation of the stenosis, at 3-week intervals up to a minimum of 3 months.

Results

Ninety-eight patients received a total of 134 treatments. The treatment was considered technically successful in 98.5 %. Drainage catheters were left in with a median duration of 14 weeks. Complications occurred in 11 patients. In 13 patients, percutaneous treatment was converted to surgical intervention. Of 85 patients in whom percutaneous treatment was completed, 11.8 % developed clinically relevant restenosis. Median follow-up was 35 months. Probability of patency at 1, 2, 5, and 10 years was 0.95, 0.92, 0.88, and 0.72, respectively. Overall, 76.5 % had successful management with PTBD. Restenosis and treatment failure occurred more often in patients who underwent multiple treatments. Treatments failed more often in patients with multiple strictures. All blood markers of liver function significantly decreased to normal values.

Conclusions

Percutaneous balloon dilation and long-term drainage demonstrate good short- and long-term effectiveness as treatment for postoperative benign biliary strictures with an acceptably low complication rate and therefore are indicated as treatment of choice.  相似文献   
83.

Purpose

Previous experience has revealed excellent outcomes when using the Meniscus Arrow (Conmed Linvatec Ltd., Tampere, Finland) bioabsorable meniscal repair system for the fixation of small fracture fragments. This study describes the results of the fixation of Mason type 2 radial head fractures with these Arrows in a prospective series of 21 patients.

Methods

Between 2006 and 2010, a total of 21 patients were treated with Meniscus Arrows for the fixation of Mason type 2 fractures of the radial head during an open procedure. Twenty-one, twenty and seventeen patients were followed up at 2 and 6 post-operative weeks, 18 weeks and 24 months, respectively. Radiographs were obtained during follow-up visits, and range of motion was classified according to the Weseley classification.

Results

At 24 post-operative months, 88 % of patients showed ‘excellent’ and 12 % showed ‘good’ results in terms of extension. All patients (100 %) showed ‘excellent’ results for flexion, supination and pronation. Uneventful healing of the fracture was observed in all patients. No complications were noted.

Conclusion

This study shows promising outcomes for the use of Meniscus Arrows as fixation devices in the treatment for Mason type 2 fractures of the radial head.

Level of evidence

Prospective therapeutic study, Level IV.  相似文献   
84.
Pilatz A  Schultheiss D  Gabouev AI  Schlote N  Mertsching H  Jonas U  Stief CG 《European urology》2005,47(5):710-8; discussion 718-9
OBJECTIVES: Primary cell cultures derived from the corpus cavernosum are frequently used as in vitro models to define cellular mechanisms involved in erectile function. However, previous studies often lack detailed isolation protocols or a precise characterisation of the culture composition excluding especially contaminating fibroblasts. This study aimed at critically analysing and reproducing reported isolation methods, as well as establishing new procedures to receive highly pure and morphologically differentiated endothelial, smooth muscle and fibroblastic cells derived from the human penis. METHODS: We evaluated numerous isolation and enrichment techniques using cavernosal tissue from 57 patients. Assessment factors displayed the purity, cell yield, practicability and reproducibility. The purity in cultured cells was analysed using immunocytochemistry and Western blots. RESULTS: An enzymatic protocol was established for the isolation and cultivation of cavernosal endothelial cells with an impressive purity of 98.0+/-0.8%. In contrast, already published nearly pure smooth muscle cell cultures were not reproducible in our laboratory. Meaningful evidence for an overwhelming presence of fibroblasts in these widely accepted pure smooth muscle cell cultures is presented. CONCLUSION: Endothelial cell cultures derived from human corpora cavernosa are reproducible and reliable to serve for cell culture-based investigations of the endothelial dysfunction. The discrepancy in the purity of smooth muscle cell cultures might reflect laboratory and tissue source factors, lacking an exclusion of fibroblasts in other studies or changes in stromal phenotype under culture conditions. Further research is necessary to clarify a possible plasticity between smooth muscle cells and (myo)fibroblasts and assess functional properties.  相似文献   
85.
Arterial complications at the site of distal interlocking screws of interlocked intramedullary nails are uncommon. This case report illustrates a 45-year-old male who was diagnosed with a pseudoaneurysm of the lateral geniculate artery when he was worked-up for persistent pain and swelling over the distal lateral thigh. He underwent obliteration of the pseudoaneurysm with thrombin injection and had excellent relief of pain and subsequent decrease in swelling. We are not aware of any case reports of pseudoaneurysm of the lateral geniculate artery at the distal screw insertion site of interlocked intramedullary nails.  相似文献   
86.

Background

Limited prospective data on the anatomic and functional outcome after laparoscopic sacrocolpopexy (LSC) are available in the literature.

Objective

To describe the medium-term anatomic and functional outcome of LSC.

Design, setting, and participants

Prospective consecutive series of 132 women with vaginal vault prolapse undergoing LSC between 2001 and 2006, which was after our learning curve. Patients with urodynamically proven stress incontinence (SI) underwent a concomitant tension-free vaginal tape (TVT) procedure.

Intervention

Patients underwent LSC with a polypropylene implant.

Measurements

Principal outcome measures were anatomic cure (stage 1 or lower) assessed by the Pelvic Organ Prolapse Quantification (POPQ) system and subjective cure and impact on quality of life measured by a standardised interview and, since its introduction in 2004, by a prolapse-specific quality-of-life questionnaire (P-QOL).

Results and limitations

At a mean follow-up of 12.5 mo, the anatomic cure rate for the apex was 98%. Anatomic failures elsewhere were mainly at the posterior compartment (18%). Subjective prolapse cure rate was 91.7%, and no patients required reoperation for recurrent prolapse. Symptoms of preoperative SI, urge incontinence, or constipation were cured in 43%, 46%, and 42% of patients, respectively. The rate of de novo SI was 7.3%. De novo constipation developed in 5% and de novo dyspareunia developed in 19%. Patients’ quality of life improved significantly. Erosions occurred in 4.5%, all within 1 yr. A limitation of the study is that the quality-of-life assessment score became available halfway through the study, limiting the number of preoperative observations (n = 36).

Conclusions

We demonstrated that LSC results in good anatomic outcome and subjective cure of prolapse symptoms at medium term. The posterior compartment was most vulnerable for recurrence.  相似文献   
87.
In this prospective, randomized, open controlled study we compared the effects on net red blood cell loss of 6% hydroxyethyl starch 130/0.4 (HES: n = 64) and 3% modified fluid gelatin (GEL: n = 68) administered for intravascular volume management in patients undergoing coronary surgery. Blood losses were calculated from determination of circulating blood volume and measurement of preoperative and postoperative hematocrit. Amount of colloids that could be administered was limited to 50 mL/kg. If additional fluids were required, balanced crystalloid solution was used. Anesthetic and surgical techniques were standardized. Both groups were similar with regard to demographic and intraoperative variables. Total study drug was 48.9 +/- 17.2 mL/kg in the HES group and 48.9 +/- 14.6 mL/kg in the GEL group. Total red blood cell loss was 544 +/- 305 mL in the HES group and 504 +/- 327 mL the GEL group. Measured blood losses were also similar in both groups (HES, 19.4 +/- 12.3 mL/kg; GEL, 19.2 +/- 14.5 mL/kg). Exposure to allogeneic blood product was comparable in both groups. In the conditions of the present study, HES 130/0.4 up to 50 mL/kg is a valuable alternative to modified fluid gelatin for plasma volume expansion during and after cardiac surgery.  相似文献   
88.
Giant cell tumor of bone (GCTB) is a benign bone tumor with a shown clinical behavior of local recurrences and rare distant metastases. GCTB is composed of uniformly distributed osteoclastic giant cells, thought to originate from the fusion of monocyte–macrophage lineage cells, in a background consisting of mononuclear rounded cells and spindle‐shaped cells. Several reports showed the specific expression of markers, such as CD14 on the mononuclear rounded cell population, however, lacking osteoclastic giant cells. Blood monocytes that were CD14+, CD33+, or CD14+/CD33+ have also been shown to be programmed as pre‐osteoclasts. The macrophage marker CD33 is expressed earlier than CD14 in macrophage maturation, whereas CD14 is expressed longer than CD33. The aim of this study was to investigate CD14/CD33 expression profiles in GCTB. Nineteen GCTB tumor samples of 19 patients were studied. Immunofluorescent analyses were performed with monoclonal antibodies against CD14, CD33, RANK, and CD51. To unambiguously further prove the expression of these molecules, quantitative RT‐PCR was used with subsequent sequencing of its products. All samples showed similar immunoreactivity profiles. The mononuclear rounded cell population was positive for RANK, CD51, CD14, and CD33. The osteoclastic giant cell population expressed RANK and CD51, as well as CD33, but was consistently negative for CD14 expression. The CD14 and CD33 profiles were confirmed by quantitative RT‐PCR. These RT‐PCR products were sequence verified. Osteoclasts in GCTB are the result of fusion of CD33‐expressing pre‐osteoclasts that further fuse with CD14+ mononuclear cells. Although these results reflect a static rather than a dynamic spectrum, we strongly believe that osteoclastogenesis seems not to be the exclusive result of fusion of intratumoral CD14+ mononuclear cells. Moreover, CD33‐modulated osteoclastogenesis opens up the possibility for novel therapeutic directions.  相似文献   
89.
Background: Classic benzodiazepine agonists induce their clinical effects by binding to a site on [gamma]-aminobutyric acid type A (GABAA) receptors and enhancing receptor activity. There are conflicting data regarding whether the benzodiazepine site is allosterically coupled to [gamma]-aminobutyric acid binding versus the channel open-close (gating) equilibrium. The authors tested the hypothesis that benzodiazepine site ligands modulate [alpha]1[beta]2[gamma]2L GABAA receptor gating both in the absence of orthosteric agonists and when the orthosteric sites are occupied.

Methods: GABAA receptors were recombinantly expressed in Xenopus oocytes and studied using two-microelectrode voltage clamp electrophysiology. To test gating effects in the absence of orthosteric agonist, the authors used spontaneously active GABAA receptors containing a leucine-to-threonine mutation at residue 264 on the [alpha]1 subunit. To examine effects on gating when orthosteric sites were fully occupied, they activated wild-type receptors with high concentrations of a partial agonist, piperidine-4-sulfonic acid.

Results: In the absence of orthosteric agonists, the channel activity of [alpha]1L264T[beta]2[gamma]2L receptors was increased by diazepam and midazolam and reduced by the inverse benzodiazepine agonist FG7142. Flumazenil displayed very weak agonism and blocked midazolam from further activating mutant channels. In wild-type receptors activated with saturating concentrations of piperidine-4-sulfonic acid, midazolam increased maximal efficacy.  相似文献   

90.
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL.  相似文献   
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