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41.
AIM To evaluate the power of six osteoporosis-screening instruments in women in a Mediterranean country.METHODS Data concerning several osteoporosis risk factors were prospectively collected from 1000 postmenopausal women aged 42-87 years who underwent dual-energy X-ray absorptiometry(DEXA) screening. Six osteoporosis risk factor screening tools were applied to this sample to evaluate their performance and choose the most appropriate tool for the study population.RESULTS The most important screening tool for osteoporosis status was the Simple Calculated Osteoporosis Risk Estimation, which had an area under the curve(AUC)of 0.678, a sensitivity of 72%, and a specificity of 72%, with a cut-off point of 20.75. The most important screening tool for osteoporosis risk was the Osteoporosis Self-assessment Tool, which had an AUC of 0.643, a sensitivity of 77%, and a specificity of 46%,with a cut-off point of-2.9.CONCLUSION Some commonly used clinical risk instruments demonstrate high sensitivity for distinguishing individuals with DEXA-ascertained osteoporosis or reduced bone mineral density.  相似文献   
42.
Purpose: The optimal surgical treatment of displaced type B and C fractures of the proximal humerus in the elderly remains controversial. Good clinical results have been reported by plating these fractures as well as a high rate of complications. Our retrospective study aims to evaluate clinical recovery and complications using the S3 locking plate in elderly patients.Methods: Fifty-one patients older than 65 years of age, with a complex proximal humeral fracture type B or C (AO classification system), were included. Patients have been followed up for a minimum of 12months. We assessed callus formation, radiological results, clinical outcome (according to the Constant Shoulder Score System) and complications. Any difference in the clinical recovery among the 2 types of fracture pattern (B and C) was investigated.Results: The mean time of fracture healing was 12.4 weeks. The mean Constant score at 3, 6 and 12months was 68, 73 and 75 respectively. No statistically significant difference in the clinical outcome was observed between the B and C fracture patterns (p > 0.05). We noticed an overall of 5 complications (9.8%). There was no need to revision any of the implants.Conclusion: Anatomic reduction and proper plate positioning are essential for minimizing implantrelated complications. In our experience the S3 angular stability system offers a proper osteosyntesis and a good clinical recovery with a low rate of complications.  相似文献   
43.

Introduction

Duodenal neuroendocrine tumors (NETs) are rare neoplasms with poorly defined management. We sought to evaluate the outcomes of patients undergoing resection of duodenal NETs.

Methods

Using a multi-institutional database, 146 patients who underwent resection for duodenal NETs between 1993 and 2015 were identified. Data on clinicopathologic characteristics and outcomes were collected and analyzed.

Results

Local surgical resection (LR) was performed in 57 (39.0 %) patients, while 50 (34.3 %) patients underwent pancreaticoduodenectomy (PD) and 39 (26.7 %) patients an endoscopic resection (ER). Factors associated with worse RFS included advanced tumor grade and metastasis at diagnosis (both P?<?0.05) but not procedure type (P?>?0.05). Among patients who had at least one lymph node examined (n?=?85), 50 (58.8 %) had a metastatic lymph node; lymph node metastasis (P?=?0.04) and advanced tumor grade (P?=?0.04) were more common among patients with tumors >1.5 cm. Median length-of-stay was longer for PD versus LR (P?<?0.001). PD patients were at increased risk for severe postoperative complications (P?=?0.01).

Conclusion

Recurrence of duodenal NETs was dependent on tumor biology rather than procedure type. PD was associated with a longer hospital stay and higher risk of perioperative complications. For patients with tumors ≤1.5 cm, LR or ER may be appropriate with PD reserved for larger lesions and those not amenable to a more local approach.
  相似文献   
44.
Characteristics of patients with stage T1b incidental prostate cancer   总被引:3,自引:0,他引:3  
OBJECTIVE: To study the characteristics of patients with incidental prostate cancer. MATERIAL AND METHODS: The proportion of incidentally diagnosed prostate cancer was investigated in patients who underwent transurethral resection of the prostate (TURP) at our clinic over a 5-year period. "True" incidental prostate cancer was defined as cases where the preoperative digital rectal examination (DRE) and the prostate-specific antigen (PSA) value were normal. Patients with known malignancy of the prostate were excluded, together with those with PSA >4 ng/ml and/or a positive DRE. The characteristics of these patients were compared to those of benign prostatic hyperplasia patients and the group as a whole. RESULTS: Of the 786 patients operated on between 1999 and 2003, 34 (4.3%) had a positive pathology report for "true" incidental prostate cancer. An increased frequency of poorly differentiated tumors (32.3%) was noted. Of the 34 patients, 17 were stage T1a and 17 T1b; 11 patients had a Gleason sum of 7-10, all of them in the T1b group. In the T1b group the mean age was 74 years, the mean PSA level 2.9 ng/ml and the mean weight of tissue resected 11.1 g. Corresponding values in the T1a patients were 70.1 years, 3.32 ng/ml and 18.2 g. CONCLUSIONS: Compared to previous studies, we noticed a low incidence of "true" incidental prostatic carcinoma but a high ratio of poorly differentiated tumors (all stage T1b). Compared to the group as a whole, patients with incidental prostate cancer were older and had smaller prostate and transition zone volumes. Further research is needed to identify parameters that may aid in the earlier identification of incidental prostate cancer, as patients may benefit from curative treatment.  相似文献   
45.

Background  

Treatment of distal tibial intra-articular fractures is challenging due to the difficulties in achieving anatomical reduction of the articular surface and the instability which may occur due to ligamentous and soft tissue injury. The purpose of this study is to present an algorithm in the application of external fixation in the management of intra-articular fractures of the distal tibia either from axial compression or from torsional forces.  相似文献   
46.
Purpose  The aim of this study is to evaluate the effectiveness of 111In-DTPA-Phe1-octreotide infusions after selective catheterization of the hepatic artery in inoperable metastasised liver, sst2 receptor-positive neuroendocrine tumours due to the effect of 111In Auger electron emission, minimising in parallel the toxicity of non-target tissue. Methods  The average dose per session administered monthly to each patient (17 cases in total) was 6.3 ± 2.3 GBq. Repetitions did not exceed 12-fold, except in one case (15 sessions). Response assessment was classified according to the Response Evaluating Criteria in Solid Tumours. CT/MRI scans were performed as baseline before, during and after the end of treatment, and monthly ultrasound images for follow-up measurements. Toxicity (World Health Organization criteria) was measured using blood and urine tests of renal, hepatic and bone marrow function. Results  Complete response was achieved in one (5.9%) patient and partial in eight (47.0%), and disease stabilization in 3 (17.7%) patients; five (29.4%) did not respond. A 32-month median survival time was estimated in 12 (70.5%). Nine of these 12 surviving had a mean target diameter shrinkage from 144 ± 81 to 60 ± 59 mm. Grade 1 erythro-, leuko- and thrombo-cytopenia occurred in three (17.6%) cases. Conclusion  In unresectable metastatic liver lesions positive for somatostatin receptors repeated, transhepatic high doses of 111In-DTPA-Phe1-octreotide show an effective therapeutic outcome. Given the locoregional modality character of the administration technique plus the extremely short range of 111In Auger and internal conversion electrons emission, no nephro-, liver- or myelo-toxicity has so far been observed.  相似文献   
47.
48.
Background and aims In extended liver resections, the preservation of vascular and biliary structures of the entire remnant liver is of paramount importance. The impact of venous outflow impairment and its consequences for liver regeneration and function are still a matter of debate. Materials and methods Rats (n = 75) were subjected to a 90% partial hepatectomy (PH), to a 70% liver resection with narrowing of the hepatic outflow of an additional 20% parenchyma (70%+ PH) or to an anatomic 70% PH. Postoperatively hepatocyte proliferation (Ki-67), liver function and survival were assessed. Gene expression analysis for markers of regeneration was determined by in-house complementary (DNA) arrays and quantitative real-time polymerase chain reaction (RT-PCR). Results Ninety percent PH led to a greater regenerative response as shown Ki-67 compared to animals with a 70%+PH (p < 0.05). However, liver function was equally impaired in both groups. Rats with 70% PH showed a greater proliferation index with less hepatic injury and better liver function. While mortality was 0% in the group of 70% PH, rats with 90% PH and 70+PH had a reduced survival of 75% (p < 0.05) Conclusion Venous outflow obstruction leads to an impairment of liver regeneration and liver function. In cases with critically small liver remnants, restoration of an adequate venous outflow may be mandatory.  相似文献   
49.
Congenital seminal vesicle cysts associated with renal agenesis are uncommon, but are currently detected more frequently with the use of sectional imaging procedures. Approximately 200 cases have been reported. The unique feature of our case is the combination of this disorder with an ipsilateral undescended testis. Our patient underwent partial vesiculectomy, in which the cyst was removed and the seminal vesicle remnant with its vas deferens was preserved. A review of the infertile cases and the impact of surgical treatment on fertility are discussed. Features that render partial vesiculectomy applicable and the potential effect of this procedure on fertility are highlighted.  相似文献   
50.
We compared estimates for base excess of extracellular fluid (BE(ecf); mmol/L) obtained in five clinically used blood gas analyzers: AVL Compact 2 (Roche Diagnostics, Mannheim, Germany), Ciba-Corning 860 (Bayer Diagnostics, Fernwald, Germany), IL 1620 (Instrumentation Laboratories, Lexington, MA), Stat Profile Ultra (Nova Biomedical, Waltham, MA), and ABL 510 (Radiometer, Copenhagen, Denmark). A total of 134 measurements per analyzer were obtained in arterial and venous blood samples from 10 patients undergoing cardiac surgery and 65 measurements per analyzer in venous blood samples from 2 healthy volunteers. The blood samples were equilibrated in a tonometer with gases of known composition (37 degrees C). Additional theoretical studies were performed to evaluate the relationship between pH and calculated BE(ecf) value (with varied PCO(2)) using the formulas of the various analyzers. The standard deviations of repeated measurements were 0.24 mmol/L for ABL 510 and approximately 0.45 mmol/L for the other 4 analyzers. The maximal systematic difference between the average of all measurements of each analyzer was 3.7 mmol/L; this was primarily attributable to differences in measuring pH, and, to a lesser extent, to differences in calculation and determination of PCO(2). Comparison of the results from samples with different oxygen saturation showed that the relative alkalinity of deoxygenated hemoglobin (Haldane effect) can also influence the determinations of BE(ecf). IMPLICATIONS: A clinically useful way to quantify nonrespiratory disturbances of the acid-base balance is calculation of the base excess of extracellular fluid by using blood gas analyzers. In this study, we found significant variability in estimates of base excess of extracellular fluid obtained with five analyzers from different manufacturers. This variability is attributable to multiple factors, including lack of correction for deoxygenated hemoglobin (Haldane effect).  相似文献   
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