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91.
92.
BACKGROUND AND PURPOSE: The gold standard treatment for upper-tract transitional-cell carcinoma is radical nephroureterectomy, but management of the distal ureter is not standardized. Two treatment options to detach the distal ureter are open cystotomy (OC) and excision of a bladder cuff or transurethral incision of the ureteral orifice (TUIUO). We compared the clinico-pathologic outcomes of these two techniques. PATIENTS AND METHODS: Hospital records were reviewed on all 51 patients who had undergone open or laparoscopic nephroureterectomy at our institution between 1 January 1990 and 30 June 2005. Patient demographics, intraoperative parameters, and pathology data were collected. The mean follow-up was 23.2 months (range 4.5-75 months) and 22.1 months (range 1-50 months) for the OC and TUIUO groups, respectively. There were no significant differences in sex, age at operation, American Society Anesthesiologists risk score, previous transitional-cell tumors, pathologic tumor grade and stage, or metastatic disease status in the two groups. RESULTS: Five patients had an unplanned incomplete ureterectomy. The bladder recurrence rates were similar in the OC group (22.2%; 6/27) and the TUIUO group (26.3%; 5/19). There were no pelvic recurrences in either group. Four of the five patients who had an incomplete ureterectomy had tumor recurrences, three in the form of metastatic disease. CONCLUSION: Management of the distal ureter by TUIUO in appropriate patients offers the same rate of bladder recurrence as OC. Incomplete ureterectomy results in a significantly higher rate of recurrence, often associated with the development of metastatic disease.  相似文献   
93.
BACKGROUND: Obese patients may be sensitive to the respiratory depressant effect of opioid analgesics. Alternative methods for analgesia may be beneficial for management of bariatric surgery. We evaluated the effect of dexmedetomidine on anesthetic requirements during surgery, hemodynamic, recovery profile and morphine use in the postoperative period. METHODS: Eighty adult patients scheduled for elective laparoscopic Roux-en-Y gastric bypass surgery were randomly assigned to one of two study groups; Group D (40 patients) received dexmedetomidine (0.8-microg/kg bolus, 0,4 microg kg(-1) h) and Group P (40 patients) received normal saline (placebo) in the same volume and rate. Intraoperative and postoperative mean blood pressure and heart rate were recorded. The total amount of intraoperative fentanyl and propofol required to maintain anesthesia were measured. Recovery profile, pain score and total amount of morphine used via patient controlled analgesia (PCA) were assessed. RESULTS: During surgery, dexmedetomidine decreased the total amount of intraoperative fentanyl and propofol required for maintenance of anesthesia compared to placebo. Patients who received dexmedetomidine showed significant decrease of intraoperative and postoperative mean blood pressure, heart rate. In the postoperative period, dexmedetomidine decreased pain scores and PCA morphine use significantly and showed better recovery profile as compared to the placebo Group. There was no difference in the incidence of postoperative nausea and vomiting (PONV) between both groups. CONCLUSION: The intraoperative infusion of dexmedetomidine decreased the total amount of propofol and fentanyl required to maintain anesthesia, offered better control of intraoperative and postoperative hemodynamics, decreased postoperative pain level, decreased the total amount of morphine used and showed better recovery profile compared with placebo.  相似文献   
94.
Background contextA physician's role within a workers' compensation injury extends far beyond just evaluation and treatment with several socioeconomic and psychological factors at play compared with similar injuries occurring outside of the workplace. Although workers' compensation statutes vary among states, all have several basic features with the overall goal of returning the injured worker to maximal function in the shortest time period, with the least residual disability and shortest time away from work.PurposeTo help physicians unfamiliar with the workers' compensation process accomplish these goals.Study designReview.MethodsEducational review.ResultsThe streamlined review addresses the topics of why is workers' compensation necessary; what does workers' compensation cover; progression after work injury; impairment and maximum medical improvement, including how to use the sixth edition of American Medical Association's (AMA) Guides to the evaluation of permanent impairment (Guides); completion of work injury claim after impairment rating; independent medical evaluation; and causation.ConclusionsIn the “no-fault” workers' compensation system, physicians play a key role in progressing the claim along and, more importantly, getting the injured worker back to work as soon as safely possible. Physicians should remain familiar with the workers' compensation process, along with how to properly use the AMA Guides.  相似文献   
95.
Right ventricular (RV) function immediately after left ventricular assist device (LVAD) implantation is a crucial prognostic factor. RV failure is linked to increased mortality and worse outcome. A phosphodiesterase 5 inhibitor, sildenafil, was shown to decrease pulmonary vascular resistance and pulmonary artery pressure post‐LVAD. We report on a series of heart failure patients, and the effect of sildenafil on the incidence of RV failure after LVAD implantation. We retrospectively analyzed the data of end‐stage heart failure patients who underwent LVAD implantation with pulmonary hypertension and RV dysfunction prior to surgery. Patients were divided into two groups; group 1: patients who received sildenafil perioperatively, and group 2: patients who did not receive sildenafil. Hemodynamic and echographic data were collected before and after surgery. Fourteen patients were included, 8 patients in group 1 and 6 in group 2. Sildenafil was administered with a mean dose of 56.2 ± 9.4 mg in group 1 and was able to significantly reduce right heart failure incidence, and to demonstrate a significant reduction in pulmonary vascular resistance, pulmonary artery pressure, transpulmonary gradient, and a significant increase in cardiac output. In conclusion, sildenafil seems to have a promising role perioperatively in preventing acute RV failure postsurgery in patients with RV dysfunction and pulmonary hypertension, requiring LVAD therapy.  相似文献   
96.

Purpose

To compare the clinical, pathological and oncological outcome of EAML with classic angiomyolipoma (AML).

Methods

A retrospective review of patients’ files with a diagnosis of AML was conducted. Both classic and epithelioid AML were compared as regard the patients’ demographics, mode of presentation, tumor features and follow-up data. The accuracy of preoperative radiological diagnosis of EAML and the postoperative pathological data were evaluated.

Results

Between November 1988 and July 2012, 1,502 renal masses were treated. Forty-two patients (2.8 %) had renal AML of whom 12 patients (28.6 %) had epithelioid morphology. All the patients with EAML were symptomatic on presentation compared to 16.7 % asymptomatic patients with classic AML. Specific diagnosis of EAML was not suggested based on preoperative radiological evaluation. In one patient, there was a venous tumor extension into the right renal vein; another patient had a solitary pulmonary nodule. Pathological data of EAML patients showed wide areas of necrosis (4 patients), atypia (6 patients), increased mitotic figures (2 patients), nuclear anaplasia, enlarged nuclei and prominent nucleoli (3 patients), and multilobulated multinucleated giant cells (5 patients). At a median follow-up period of 12 and 9 months for EAML and classic AML groups, respectively, one patient with EAML had evidence of both local recurrence and distant metastasis 3 months following open radical nephrectomy.

Conclusion

Epithelioid AML is potentially aggressive and usually present as a symptomatic renal mass. It may be misdiagnosed as malignant renal mass on preoperative radiological evaluation.  相似文献   
97.

Background

Hepatitis B (HBV)-associated hepatocellular carcinoma (HCC) is often associated with alpha-fetoprotein (AFP) production. Although serum AFP has been demonstrated to be a prognostic factor for patient survival, optimal cutoff levels remain unclear.

Methods

Patients with HBV-associated HCC treated by primary liver resection were prospectively followed at a single institution between 1995 and 2008. AFP level was categorized into quintiles for Kaplan–Meier analysis and multivariable Cox proportional hazards regression models.

Results

Best 5-year survival after surgery was observed for patients with AFP in the first quintile (1.4–4.1 ng/mL), with progressively worse outcomes for patients in each increasing quintile. AFP was associated with overall survival (HR = 1.61; 95 % CI 1.30–1.98), disease-free survival (HR = 1.26; 95 % CI 1.10–1.44), and 2-year recurrence (HR = 1.30; 95 % CI 1.07–1.57) in multivariate analysis. Noncirrhotic patients (Ishak 1–5) with AFP in quintile 1 had 94 % 5-year survival, compared with 0 % survival for patients with AFP in quintile 5 (2,332.7–327,560.0 ng/mL) and Ishak stage 6 cirrhosis.

Conclusions

Preoperative serum AFP is an independent predictor of prognosis among HBV-HCC patients following surgical resection. Categorizing AFP into quintiles creates the opportunity to observe differences in outcomes even at low serum levels within the normal range. Additionally, combining AFP quintiles and fibrosis staging provides a predictive model of prognosis for HCC. Thus, even small differences in AFP within the normal range may impact prognosis and disease progression for HBV-HCC.  相似文献   
98.
The need for orthodontic treatment is increasing all the time. As the treatment is time consuming ranging from a year to several years, any method of reducing the period of treatment and increasing the quality of the tissue will be beneficial to patients. The use of non-invasive techniques such as low level laser therapy and low intensity pulsed ultasound in accelerating orthodontic tooth movement are promising. Thus, this overview study will help to generate more understanding about the background information and the possible applications of them in daily orthodontics, depending on previous literature searching for reviews and original research articles.  相似文献   
99.
The present study was performed to show the ameliorative effect of berberine (BBR), as an antioxidant and anti‐inflammatory agent, against experimental varicocele (VCL)‐induced molecular and histological damages. For this purpose, 50 mature Wistar rats were divided into control, control‐sham, VCL‐sole, 50 mg/kg and 100 mg/kg BBR‐treated VCL‐induced groups. The tissue levels of interleukin‐6 (IL‐6), tumour necrosis factor‐α (TNF‐α), nitric oxide (NO), total antioxidant capacity (TAC), malondialdehyde (MDA), superoxide dismutase (SOD) and gluthatione peroxidase (GSH‐px) as well as the mRNA levels of testicular CuZn SOD, MnSOD, EC‐SOD and GSH‐px were evaluated. The serum concentration of testosterone and germ cells mRNA damage were analysed. Finally, the sperm viability, motility, DNA integrity and chromatin condensation were analysed. Observations revealed that, the BBR significantly downregulated VCL‐increased IL‐6, TNF‐α and NO levels, upregulated the CuZn SOD, MnSOD, EC‐SOD and GSH‐px mRNA level, decreased testicular MDA content, enhanced serum testosterone level and ameliorated testicular TAC, SOD and GSH‐px levels. The animals in BBR‐treated groups exhibited diminished mRNA damage versus non‐treated VCL‐induced group. The BBR has significantly (p < 0.05) improved sperm parameters. In conclusion, the BBR by promoting testicular antioxidant potential and by downregulating inflammatory reactions fairly promotes spermatogenesis and upregulates the sperm quality.  相似文献   
100.
Background contextApproximately 25% of vertebroplasty patients experience subsequent fractures within 1 year of treatment, and vertebrae adjacent to the cemented level are up to three times more likely to fracture than those further away. The increased risk of adjacent fractures postaugmentation raises concerns that treatment of osteoporotic compression fractures with vertebroplasty may negatively impact spine biomechanics.PurposeTo quantify the biomechanical effects of vertebroplasty on adjacent intervertebral discs (IVDs) and vertebral bodies (VBs).Study designA biomechanics study was conducted using cadaveric thoracolumbar spinal columns from elderly women (age range, 51–98 years).MethodsFive level motion segments (T11–L3) were assigned to a vertebroplasty treated or untreated control group (n=10/group) such that bone mineral density (BMD), trabecular architecture, and age were similar between groups. Compression fractures were created in the L1 vertebra of all specimens, and polymethylmethacrylate bone cement was injected into the fractured vertebra of vertebroplasty specimens. All spine segments underwent cyclic axial compression for 115,000 cycles. Microcomputed tomography imaging was performed before and after cyclic loading to quantify compression in adjacent VBs and IVDs.ResultsCyclic loading increased strains 3% on average in the vertebroplasty group when compared with controls after 115,000 cycles. This global strain manifested locally as approximately fourfold more compression in the superior VB (T12) and two- to fourfold higher axial and circumferential deformations in the superior IVD (T12–L1) of vertebroplasty-treated specimens when compared with untreated controls. Low BMD and high cement fill were significant factors that explained the increased strain in the vertebroplasty-treated group.ConclusionsThese data indicate that vertebroplasty alters spine biomechanics resulting in increased compression of adjacent VB and IVD in severely osteoporotic women and may be the basis for clinical reports of adjacent fractures after vertebroplasty.  相似文献   
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