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101.
To validate the adverse effects of subluxation of the femoral head in Legg-Calve-Perthes disease, the authors made an experimental model of Perthes disease with subluxation in growing rabbits by interrupting the epiphyseal artery (devascularization) and immobilizing the knee in extension (immobilization). Seventy-two rabbits, 4 to 5 weeks old, were divided into three groups: group A with both devascularization and immobilization (25 rabbits), group B with devascularization only (25 rabbits), and group C with immobilization only (22 rabbits). In each experimental group, four to six rabbits each were killed at 1, 2, 4, 8, and 12 weeks. After reviewing the serial radiographs and gross specimens, the authors found six radiologic and six macroscopic abnormalities. The incidence and the severity of deformity in group A rabbits were higher than that of groups B or C in terms of the overall incidence of deformities (P <0.001), head deformity scores (P <0.001), and the incidence of a total collapse of the capital femoral epiphysis. In conclusion, subluxation of the immature femoral head with avascular necrosis in rabbits increased femoral head deformities.  相似文献   
102.

Introduction

We studied the incidence of vesicoureteral reflux (VUR) in the graft kidney and its effect on the occurrence of urinary tract infection (UTI) and long-term graft function.

Methods

We performed a retrospective analysis of 64 adult kidney transplant recipients based upon voiding cystourethrography at 12 months post-transplantation. Patients underwent analysis of survival, incidence of UTIs beyond 1 year, and graft function.

Results

Thirty-seven male and 27 female patients in the study populations showed a mean age 42 years. VUR in the transplanted kidney at 12 months post-transplant occurred among 78.1% (50/64) of subjects: grade I (n = 6), grade II (n = 30), or grade III (n = 14) reflux. Patients followed for a median 61 months (range 44–74s) showed 11 cases of UTIs in 9 subjects. There were no significant differences in clinical characteristics or incidence of, UTIs according to the presence or severity of VUR (P = .81) or the Serum creatinine and estimated glomerular filtration rate values at 12, 36, 48, or 60 months post-transplantation.

Conclusions

VUR present in 78.1% of patients after kidney transplantation affected neither graft functions or graft survival. The incidence of UTI did not differ according to the presence of VUR.  相似文献   
103.

Purpose

To cope with recipient portal vein (PV) anomalies, such as early branching of the right posterior section (RPS), during living donor liver transplantation (LDLT) surgery, we performed a simulation study to standardize the surgical technique for unification portal venoplasty.

Methods

This study included an observational analysis of conventional methods utilizing RPS PV, simulation-based design of a new surgical technique, and clinical application of this new technique.

Results

In a case encountering RPS PV, a mild anastomotic PV stenosis was persistent over 6 months postsurgery, indicating the need for technical refinement. After computational simulation analysis, we found that simple suturing of the PV branch patch automatically resulted in a funnel-shaped elongation. A prospective recipient study (n = 30) indicated that usual PV reconstruction via the PV bifurcation method is feasible in the absence of unusual donor or recipient PV anomaly. Retrospective living donor PV anatomy analysis (n = 20) revealed that 20-mm-long limbs of the first-order PV branches are necessary to make a 10- to l5-mm-long funneled PV stump. This technique of unification venoplasty for an anomalous recipient PV was applied to an adult patient undergoing LDLT with a right liver graft, for which it was shown to be technically feasible and effective.

Conclusions

A simplified unification venoplasty technique was developed to cope with a recipient PV anomaly in adult LDLT.  相似文献   
104.

Background

The high incidence of percutaneous transhepatic biliary drainage (PTBD) tract recurrence after resection of perihilar bile duct cancer (BDC) at a reference single center has suggested the need for endoscopic biliary drainage (EBD) to prevent PTBD-related tumor recurrence. To determine the general applicability of these findings, we validated the risk of PTBD tract recurrence in patients with resected BDC in our high-volume center.

Methods

The medical records of 306 patients with perihilar BDC who underwent hepatobiliary resection with curative intent over 10?years were reviewed retrospectively.

Results

Of the 306 patients, 293 (95.8%) underwent biliary decompression, 171 (56.1%) by preoperative PTBD, 62 (20.3%) by EBD alone, and 60 (19.7%) by both. Of the 231 patients who underwent PTBD, 160 (69.3%), 62 (26.8%), and 9 (3.9%) had one, two, or three catheters, respectively (mean of 1.3 catheters per patient for a median 23?days). No patient experienced synchronous PTBD tract metastasis, whereas 4 (1.7%) experienced PTBD tract recurrence a median 13.5?months after surgery, with 3 of these patients having an intraabdominal recurrence soon afterward. Only one patient had a solitary tract recurrence without intraabdominal metastasis. These patients survived for a median 25?months, which is comparable to survival outcomes after noncurative resection. No risk factor was significantly associated with PTBD tract recurrence.

Conclusions

We think that the risk of PTBD tract recurrence after resection of perihilar BDC is not negligible but is much lower than previously reported. There is no definitive reason to avoid PTBD when it is indicated.  相似文献   
105.
This prospective study evaluated the safety of tadalafil 5 mg taken once a day in terms of hypotensive side effects and whether it improves lower urinary tract symptoms (LUTS) and restores sexual function in patients with erectile dysfunction who are receiving concomitant α-blocker (AB) therapy for benign prostatic hyperplasia (BPH). A total of 158 LUTS/BPH patients receiving AB therapy for ≥3 months were given tadalafil 5 mg once a day. Before treatment with tadalafil (V1), and 4 weeks (V2) and 12 weeks (V3) after starting tadalafil, blood pressure, heart rate, International Prostate Symptom Score (IPSS), maximal urine flow rate (Qmax), postvoiding residual urine volume, and International Index of Erectile Function (IIEF-5) score were measured. Of the 158 LUTS/BPH patients, a total of 119 completed the trial. Blood pressure (systolic and diastolic) and heart rate did not change. IPSS and IIEF-5 scores improved significantly, but Qmax and postvoiding residual urine volume did not; however, in the 39 men with a low baseline Qmax (≤10 mL/s), Qmax rose significantly from 7.97 ± 1.44 mL/s (baseline) to 8.91 ± 1.60 mL/s (V3; P = .012). The remaining patients (baseline Qmax >10 mL/s) did not change. At V2 and V3, adverse side effects were observed in 10 men (7.30%) and 6 men (5.04%), respectively. Facial flushing was the most common adverse side effect (6 men at V2 and 4 men at V3), followed by headache (2 men each at V2 and V3) and dizziness (2 men at V2). Two patients dropped out of the study because of adverse side effects. In conclusion, tadalafil 5 mg once a day in combination with AB appeared to have few adverse effects on hypotensive events and can improve LUTS and restore sexual function.  相似文献   
106.
Study ObjectiveTo determine the optimal dose of esmolol in combination with nicardipine in effectively blocking undesirable cardiovascular responses during rapid-sequence induction.DesignProspective, randomized clinical comparison study.SettingOperating room of a university hospital.Patients200 ASA physical status 1 and 2 patients requiring general anesthesia with endotracheal tube placement.InterventionsPatients were randomly allocated into one of 4 groups: Group E0 (no esmolol; control), Group E0.25 (esmolol 0.25 mg/kg), Group E0.5 (esmolol 0.5 mg/kg), and Group E1.0 (esmolol 1.0 mg/kg). All patients received 20 μg/kg of nicardipine, and esmolol was then given according to group allocation. Ninety seconds later, thiopental sodium 5 mg/kg and succinylcholine 1.0 mg/kg were injected. Endotracheal intubation was performed 60 seconds after injection of the anesthetic agents.MeasurementsSystolic (SBP), diastolic (DBP), and mean arterial (MAP) pressures; heart rate (HR), and rate-pressure product (RPP) were measured 30 seconds before and after intubation, and at 1, 3, 5, and 10 minutes after intubation. Rate changes using baseline values as the standard [rate changes = measured value/baseline value × 100 (%)] were calculated.Main ResultsSignificant attenuations in SBP, MAP, HR, and RPP after intubation were noted in the experimental groups as compared with the control group (P < 0.05). Rate changes in HR in Groups E0.5 and E1.0 were significantly lower than those in Group E0.25 immediately and one minute after intubation (P < 0.05). No difference in rate changes in HR were noted between the E0.5 and E1.0 groups.ConclusionsThe combination of nicardipine 20 μg/kg and esmolol 0.5 mg/kg most effectively attenuates the cardiovascular responses during rapid-sequence induction.  相似文献   
107.

Background

Intra-class correlation coefficients (ICCs) provide a statistical means of testing the reliability. However, their interpretation is not well documented in the orthopedic field. The purpose of this study was to investigate the use of ICCs in the orthopedic literature and to demonstrate pitfalls regarding their use.

Methods

First, orthopedic articles that used ICCs were retrieved from the Pubmed database, and journal demography, ICC models and concurrent statistics used were evaluated. Second, reliability test was performed on three common physical examinations in cerebral palsy, namely, the Thomas test, the Staheli test, and popliteal angle measurement. Thirty patients were assessed by three orthopedic surgeons to explore the statistical methods testing reliability. Third, the factors affecting the ICC values were examined by simulating the data sets based on the physical examination data where the ranges, slopes, and interobserver variability were modified.

Results

Of the 92 orthopedic articles identified, 58 articles (63%) did not clarify the ICC model used, and only 5 articles (5%) described all models, types, and measures. In reliability testing, although the popliteal angle showed a larger mean absolute difference than the Thomas test and the Staheli test, the ICC of popliteal angle was higher, which was believed to be contrary to the context of measurement. In addition, the ICC values were affected by the model, type, and measures used. In simulated data sets, the ICC showed higher values when the range of data sets were larger, the slopes of the data sets were parallel, and the interobserver variability was smaller.

Conclusions

Care should be taken when interpreting the absolute ICC values, i.e., a higher ICC does not necessarily mean less variability because the ICC values can also be affected by various factors. The authors recommend that researchers clarify ICC models used and ICC values are interpreted in the context of measurement.  相似文献   
108.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
109.

Purpose

Hypoxia is an important factor influencing tumor progression and treatment efficacy. The aim of this study was to investigate the repeatability of hypoxia PET imaging with [18F]HX4 in patients with head and neck and lung cancer.

Methods

Nine patients with lung cancer and ten with head and neck cancer were included in the analysis (NCT01075399). Two sequential pretreatment [18F]HX4 PET/CT scans were acquired within 1 week. The maximal and mean standardized uptake values (SUVmax and SUVmean) were defined and the tumor-to-background ratios (TBR) were calculated. In addition, hypoxic volumes were determined as the volume of the tumor with a TBR >1.2 (HV1.2). Bland Altman analysis of the uptake parameters was performed and coefficients of repeatability were calculated. To evaluate the spatial repeatability of the uptake, the PET/CT images were registered and a voxel-wise comparison of the uptake was performed, providing a correlation coefficient.

Results

All parameters of [18F]HX4 uptake were significantly correlated between scans: SUVmax (r?=?0.958, p?<?0.001), SUVmean (r?=?0.946, p?<?0.001), TBRmax (r?=?0.962, p?<?0.001) and HV1.2 (r?=?0.995, p?<?0.001). The relative coefficients of repeatability were 15 % (SUVmean), 17 % (SUVmax) and 17 % (TBRmax). Voxel-wise analysis of the spatial uptake pattern within the tumors provided an average correlation of 0.65?±?0.14.

Conclusion

Repeated hypoxia PET scans with [18F]HX4 provide reproducible and spatially stable results in patients with head and neck cancer and patients with lung cancer. [18F]HX4 PET imaging can be used to assess the hypoxic status of tumors and has the potential to aid hypoxia-targeted treatments.
  相似文献   
110.

Objectives

The aim of our study was to evaluate the tumour volume doubling time (TVDT) of molecular breast cancer subtypes by serial ultrasound (US).

Methods

Sixty-six patients (mean age, 50 years; range, 29–78 years) with invasive breast cancer underwent initial and follow-up breast US examinations (at least three months apart) with no intervention. TVDT was determined using the tumours’ greatest dimensions in two orthogonal planes. The results were compared with clinical, imaging, and tumour variables and molecular subtypes (oestrogen receptor [ER]-positive, human epidermal growth factor receptor 2 [HER2]-positive, and triple negative) using a multiple linear regression analysis.

Results

TVDT exhibited a wide range (46–825 days; median, 141 days) with an overall mean of 193?±?141 days and mean values of 241?±?166 days for ER-positive tumours (n?=?37), 162?±?60 days for HER2-positive tumours (n?=?12), and 103?±?43 days for triple-negative tumours (n?=?17) (P?P?Conclusions TVDT differed significantly among the three molecular breast cancer subtypes, with the triple-negative tumours showing the fastest growth.

Key Points

? Knowledge of tumour volume doubling time provides clues for improving screening. ? TVDT assessed by serial US differed significantly between breast cancer subtypes. ? Triple-negative tumours had 2.4-fold shorter TVDT compared to ER-positive tumours. ? Tumours classified as BI-RADS 3 had shorter TVDT than BI-RADS 4.  相似文献   
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