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61.
The objectives of this study were to propose a model for exercise- induced muscle injury by way of a maximal eccentric isokinetic exercise at low angular speed, and assess the time course of functional recovery of the injured quadriceps femoris muscle from the maximal voluntary contraction (MVC) torque and electrical activity (root mean square - RMS and median frequency - MDF). The effectiveness of the proposed eccentric exercise in inducing injury was assessed from the activity of creatine kinase (CK). In addition, the presence of edema of the quadriceps femoris muscle was assessed by a visual inspection of the intensity of the magnetic resonance imaging (MRI) signal. These measurements were carried out before and after the exercise. Ten healthy women (21.9 ± 1.5) took part in this study. The injury was induced by 4 series of 15 maximal eccentric isokinetic contractions at 5°/s. The MVC torque reduced up to the 4th day after the exercise (p < 0.05). The RMS of the vastus medialis oblique (VMO) and the rectus femoris (RF) muscles decreased on the 2nd (VMO and RF; p < 0.05) and 3rd (RF; p < 0.05) days after. The MDF of the VMO increased immediately after (p < 0.05), whilst the MDF of the RF and VL decreased immediately after (RF; p < 0.05), on the 1st (RF and VL; p < 0.05) and on the 2nd (VL; p < 0.05) days after. The CK activity increased on the 2nd day after (p < 0.05). An increase in the intensity of the MRI signal was observed on the 2nd and 7th days after. In conclusion: 1- the eccentric exercise with low angular speed was effective in inducing injury, 2- the quadriceps femoris already started its functional recovery, as shown by the MVC torque and electrical activity, in the first week after the exercise, despite the presence of an increase in the intensity of the MRI signal.

Key points

  • The low angular speed eccentric exercise was effec-tive in inducing injury of the quadriceps femoris muscle, and could be used as a muscle injury induc-ing model in future studies;
  • The quadriceps femoris muscle injured by eccentric exercise started its functional recovery in the first week after low angular speed eccentric exercise.
Key words: Muscle damage, torque, electromyography, magnetic resonance imaging, creatine kinase  相似文献   
62.
PURPOSE: The biological behavior and clinical outcome of renal cell carcinoma are difficult to predict. We investigated the prognostic impact of clinicopathological variables to establish a risk stratification model to predict recurrence and survival rates. MATERIALS AND METHODS: We studied 230 patients with renal cell carcinoma (stages T(1-4) N(x) M(0)) who underwent radical nephrectomy and/or nephron sparing surgery, and were followed for a median of 48 months (range 3 to 140). Univariate and multivariate analyses were performed, and the influence of clinical presentation, histological tumor size, tumor grade, lymph node involvement and microvascular tumor invasion on disease-free and cancer specific survival curves was determined. A composition model based on independent prognostic variables was then created to stratify tumors into low, intermediate and high risk of progression. RESULTS: The tumor recurrence rate was 17% (39 of 230) and the cancer specific mortality rate was 13% (31 of 230). Multivariate analyses determined that microvascular tumor invasion, tumor grade and tumor size were the only independent prognostic factors. Disease-free survival rates for low, intermediate and high risk tumors were 94.7%, 56.8% and 13.1%, respectively. Cancer specific survival rates were 94.7%, 61.7% and 32.0%, respectively. CONCLUSIONS: Tumor size, Fuhrman grade and microvascular tumor invasion are strong and independent predictors of survival of patients with renal cell carcinoma. Risk assessment and stratification based on this triad of pathological features may allow better individualization of followup schedules and trials of adjuvant treatment for patients with renal cell carcinoma.  相似文献   
63.
OBJECTIVE: The objective of this study was to radiographically quantify bone density and bone height preservation in tooth extraction alveolus filled with xenograft. STUDY DESIGN: The maxillary and mandibular fourth deciduous molars and fourth premolars of 6 minipigs were removed. Randomly, in 3 animals the right side was used as the test side and in the other 3 animals the left side was the test side. Intraoral radiographs were performed to compare the condition at the initial time and 3 months later. Measurements of bone height and bone density were performed using KS300 (Zeiss) software. RESULTS: After 3 months, there was a statistically significant smaller bone height loss for the test group. The test group presented a statistically greater bone density immediately after tooth extraction. However, after 3 months there was no statistically significant difference between the groups. CONCLUSIONS: The results suggest that treatment of postextraction alveolus with xenograft can preserve bone height initially but differences in bone density compared to when no xenograft is used are not sustained.  相似文献   
64.
65.
The purpose of this study was to determine whether the acute hormone response to exercise differed between low intensity blood flow restricted resistance exercise and traditional high-intensity resistance exercise in college-aged women. A total of 13 healthy women (aged 18-25 yrs), who were taking oral contraceptives, volunteered for this randomized crossover study. Subjects performed a session of low intensity blood flow restricted resistance exercise (BFR) (20% of 1-RM, 1 set 30 reps, 2 sets 15 reps) and a session of traditional high intensity resistance exercise without blood flow restriction (HI) (3 sets of 10 repetitions at 80% of 1-RM) on separate days. Fasting serum cortisol and growth hormone (GH) and blood lactate responses were measured in the morning pre and post exercise sessions. GH (Change: HI: 6.34 ± 1.72; BFR: 4.22 ± 1.40 ng·mL-1) and cortisol (Change: HI: 4.46 ± 1.53; BFR: 8.10 ± 2.30 ug·dL-1) significantly (p < 0.05) increased immediately post exercise for both protocols compared to baseline and there were no significant differences between the protocols for these responses. In contrast, blood lactate levels (HI: 7.35 ± 0.45; BFR: 4.02 ± 0.33 mmol·L-1) and ratings of perceived exertion were significantly (p < 0.01) higher for the HI protocol. In conclusion, acute BFR restricted resistance exercise stimulated similar increases in anabolic and catabolic hormone responses in young women.

Key Points

  • Growth hormone and cortisol levels significantly increased after a single bout of low intensity blood flow restricted resistance exercise in young women.
  • There were no significant differences in hormone responses between the low intensity blood flow restricted protocol and the traditional high intensity higher total workload protocol.
  • Low intensity blood flow restricted resistance exercise provides a sufficient stimulus to elicit anabolic and catabolic hormone responses in young women.
Key Words: Growth Hormone, Cortisol, blood flow restriction  相似文献   
66.

Background

Hepatic resection has evolved to become safer, thereby making it possible to expand the indications.

Aim

To assess the results from a group of patients presenting these expanded indications.

Method

Were prospectively studied all the hepatectomy procedures performed for hepatic tumor resection. Patients with benign and malignant primary and secondary tumors were included. Were included variables such as age, gender, preoperative diagnosis, preoperative treatment, type of operation performed, need for transfusion, final anatomopathological examination and postoperative evolution. The patients were divided into two groups: group A, with a traditional indication for hepatectomy; and group B, with an expanded indication (tumors in both hepatic lobes, extensive resection encompassing five or more segments, cirrhotic livers and postoperative chemotherapy using hepatotoxic drugs).

Results

Were operated 38 patients, and 40 hepatectomies were performed: 28 patients in group A and 10 in group B. The mean age was 57.7 years, and 25 patients were women. Three in group B were operated as two separate procedures. Groups A and B received means of 1.46 and 5.5 packed red blood cell units per operation, respectively. There were three cases with complications in group A (10.7%) and six in group B (60%). The mortality rate in group A was 3.5% (one patient) and in groups B, 40% (four patients). The imaging examinations were sensitive for the presence of tumors but not for defining the type of tumor. The blood and derivative transfusion rates, morbidity and mortality were greater in the group with expanded indications and more extensive surgery.

Conclusion

The indications for liver biopsy and portal vein embolization or ligature can be expanded, with special need of cooperation of the anesthesiology department and the use of hepatic resection devices to diminish blood transfusion.  相似文献   
67.
ObjectivesNo guidelines exist for the management of micropapillary bladder cancer (MPBC) and most reports of this variant of urothelial carcinoma are case series comprising small numbers of patients. We sought to determine current practice patterns for MPBC using a survey sent to the Society of Urologic Oncology (SUO) and to present those results in the setting of a comprehensive review of the existing literature.Materials and methodsA survey developed by the Translational Science Working Group of the Bladder Cancer Advocacy Network–sponsored Think Tank meeting was distributed to members of the SUO. The results from 118 respondents were analyzed and presented with a literature review.ResultsMost survey respondents were urologists, with 80% considering bladder cancer their primary area of interest. Although 78% of the respondents reported a dedicated genitourinary pathologist at their institution, there were discrepant opinions on how a pathologic diagnosis of MPBC is determined as well as variability on the proportion of MPBC that is clinically significant. Among them, 78% treat MPBC differently than conventional urothelial carcinoma, with 81% reporting that they would treat cT1 MPBC with upfront radical cystectomy. However, the respondents had split opinions regarding the sensitivity of MPBC to cisplatin-based chemotherapy, which affected utilization of neoadjuvant chemotherapy in muscle-invasive disease.ConclusionsThe management of MPBC is diverse among members of the SUO. Although most favors early cystectomy for cT1 MPBC, there is no consensus on the use of neoadjuvant chemotherapy for muscle-invasive MPBC.  相似文献   
68.

Background

Ethnic disparities in trauma mortality outcomes have been demonstrated in the United States according to the US National Trauma Data Bank. The aim of this study was to determine the effect of race/ethnicity on trauma mortality in Singapore.

Methods

This was a retrospective review of patients aged 18–64 years with an injury severity score (ISS) ≥9 in the Trauma Registry of Tan Tock Seng Hospital, a 1,300-bed trauma center in Singapore, from 2006 to 2010. Chinese, Malay, and Indian patients were compared with patients of other ethnic groups. Multiple logistic regression analyses determined differences in survival rates after adjusting for demographics, anatomic and physiologic ISS and revised trauma score, mechanism or type of injury.

Results

A total of 4,186 patients (66.4 % of the database) met the inclusion criteria. Most patients were male (76.3 %) and young (mean age 40 years). Using Chinese as the reference group, we found no statistically significant differences in unadjusted or adjusted mortality rates among the ethnic groups. Independent predictors of mortality included age [odds ratio (OR) 1.05, 95 % confidence interval (CI) 1.03–1.06, p < 0.0001], presence of severe head injury (OR 1.75, 95 % CI 1.13–2.69, p = 0.012), and increasing ISS (p < 0.0001).

Conclusions

Ethnicity is not an independent predictor of trauma mortality outcomes in the Singapore population. Our findings contrast with those from the United States, where race/ethnicity (Black and Hispanic) remains a strong independent risk factor for trauma mortality. This study attests to the success of the Singapore health care/trauma system in delivering the same quality of care regardless of ethnicity.  相似文献   
69.
70.
PURPOSE: Renal cell carcinoma is a tumor with unpredictable behavior and defining reliable prognostic factors would be extremely valuable in the clinical setting. Tumor stage, nuclear grade and tumor cell type are the main prognostic clinical parameters available. In this study we evaluated the role of microvascular involvement in the primary lesion for predicting tumor behavior in patients with low stage clinical disease. MATERIALS AND METHODS: A total of 95 patients with clinically localized renal cell carcinoma (stages T1-T2 Nx M0) underwent radical nephrectomy and/or nephron sparing surgery, and were followed for a median of 45 months. The impact of microvascular tumor invasion on disease progression and its correlation with known pathological outcomes (tumor size, nuclear grade and cell type) were studied. RESULTS: Microvascular tumor invasion was observed in 24 patients (25%), of whom 50% had disease recurrence. Of the 71 patients without microvascular invasion only 4 (6%) showed tumor recurrence. When microvascular invasion was correlated with other histological parameters, a significant statistical association was noted with tumor diameter, perirenal fat invasion, macroscopic extension to the renal vein, nuclear grade, lymph node metastasis and sarcomatous elements in the tumor. Multivariate analysis showed that microvascular invasion and the involvement of regional lymph nodes were independent predictors of disease recurrence. Concerning cancer specific survival, microvascular invasion and perirenal fat infiltration were the only factors related to death. CONCLUSIONS: Microvascular invasion is an independent and relevant clinical prognostic parameter for low clinical stage renal cell carcinoma.  相似文献   
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