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71.
P C Dell 《Hand Clinics》1987,3(4):563-583
Dislocations of the DRUJ, when diagnosed promptly, may be successfully treated by closed reduction and immobilization. Symptomatic tears of the TFCC may be decompressed by ulnar shortening with or without debridement of the tear. Several operations are available for the treatment of derangements of the DRUJ. The Lauenstein procedure maintains TFCC function and restores stable painful forearm rotation.  相似文献   
72.
A method was devised to quantitate regional capillary perfusion in the human heart by measuring the clearance constants (k) of Xenon-133 washout from multiple areas of the myocardium with a multiple-crystal scintillation camera. In 17 subjects, (133)Xe was injected into the right or left coronary artery or both and counts per second (cps) were recorded simultaneously on magnetic tape from each of 294 scintillation crystals viewing the precordium through a multichannel collimator. Data were processed by a digital computer. Crystals detecting the myocardial washout of (133)Xe were distinguished from those monitoring pulmonary excretion by positioning radioactive markers at the cardiac margins, and by a computer printout of the peak cps recorded by each crystal and its time after isotope injection into the coronary artery. The slopes of the initial segment of the multiple (133)Xe curves obtained in each study were calculated by the method of least squares using a monoexponential model. Myocardial blood flow rates in the cardiac regions viewed by the individual crystals were calculated (assuming a blood to myocardium partition coefficient of 0.72) along with the SD of every flow measurement. The pattern of myocardial perfusion rates so obtained was superimposed over a tracing of the subject's coronary arteriogram. Scintiphotographs showing the arrival and washout of isotope from various regions of myocardium and the area of tissue perfused by each coronary artery were obtained by replaying the data tape on an oscilloscope. Significant regional variations in local myocardial perfusion rates were observed in hearts with normal coronary arteries. When capillary flow measurements from crystals overlying the various cardiac chambers were averaged in each subject, the mean myocardial blood flow rate of the left ventricle in 17 patients, 64.1 +/-13.9 (SD) ml/100 g.min, significantly exceeded that of the right ventricle, 47.8 +/-10.9 ml/100 g.min, and of the right atrial region, 33.6 +/-10.3 ml/100 g.min. The approach may facilitate more objective assessment of: myocardial capillary perfusion in patients with angina pactoris, the pharmacology of antianginal drugs, and the efficacy of surgical procedures to revascularize ischemic myocardium.  相似文献   
73.

Background

Salvage radiation therapy (SRT) is a recommended treatment option for biochemical recurrence after radical prostatectomy (RP). However, its effectiveness may be limited to specific categories of patients.

Objective

We aimed to identify the optimal candidates for early SRT after RP.

Design, setting, and participants

The study included 925 node-negative patients treated with SRT after RP at seven institutions. Patients received SRT for either prostate-specific antigen (PSA) rising, or PSA persistence after RP that was defined as PSA level ≥0.1 ng/ml at 1 mo after surgery. All patients received local radiation to the prostate and seminal vesicle bed.

Outcome measurements and statistical analysis

The primary outcome measured was distant metastasis after SRT. Regression tree analysis was used to develop a risk-stratification tool. Multivariable Cox regression analysis and nonparametric curve fitting methods were used to explore the relationship between PSA level at SRT and the probability of metastasis-free survival at 8 yr.

Results and limitations

At a median follow-up of 8.0 yr, 130 patients developed distant metastasis. At multivariable analysis, pre-SRT PSA level was significantly associated with distant metastasis (hazard ratio: 1.06, p < 0.0001). However, when patients were stratified into five risk groups using regression tree analysis (area under the curve: 85%), early SRT administration provided better metastasis-free survival in three groups only: (1) low risk: undetectable PSA after RP, Gleason score ≤7, and tumour stage ≥pT3b, (2) intermediate risk: undetectable PSA after RP with Gleason score ≥8, (3) high risk: PSA persistence after RP with Gleason score ≤7.

Conclusions

We developed an accurate risk stratification tool to facilitate the individualised recommendation for early SRT based on prostate cancer characteristics. Early SRT proved to be beneficial only in selected groups of patients who are more likely to be affected by clinically significant but not yet systemic recurrence at the time of salvage treatment administration.

Patient summary

In patients affected by prostate cancer recurrence after radical prostatectomy, the early administration of salvage radiation therapy is beneficial only for selected subgroups of patients. In this study, these groups of patients were identified.  相似文献   
74.
High school grade point averages, Scholastic Aptitude Test verbal and quantitative scores, and National League for Nursing Pre-Nursing Examination scores were obtained for 456 black students enrolled in a private baccalaureate school of nursing. Discriminant analysis showed that these measures significantly differentiated between dropouts and graduates. For 181 graduates, these same predictors plus college grade point average also significantly differentiated between passers and failers on the State Board Examination.  相似文献   
75.

Objective

Several randomized controlled trials have documented significant overall survival benefit in high metastatic risk prostate cancer (PCa) patients treated with combination of androgen deprivation therapy (ADT) at radiotherapy (RT) relative to RT alone. Unfortunately, elderly patients are either not included or are underrepresented in these trials. In consequence, the survival benefit of combination of ADT at RT in the elderly warrants detailed reassessment, including its cost.

Methods

Between 1991 and 2009 within the Surveillance Epidemiology and End Results (SEER)-Medicare-linked database, we identified 3,692 patients aged 80 years or more with clinical T1–T2 PCa and WHO histological grade 3, or clinical T3–T4 PCa and any histological grade, treated with or without combination of ADT at RT. Competing risks analyses focused on cancer-specific mortality (CSM) and other-cause mortality, after accounting for confounders. All analyses were repeated in patients with no comorbidity and in most contemporary patients, treated between 2001 and 2009. Finally, we assessed median annual cost according to use of combination of ADT at RT, after adjusting for patient and tumor characteristics.

Results

In competing-risks multivariable analyses, no statistically significant difference was observed in CSM and other-cause mortality between patients treated with or without combination of ADT at RT. Same results were recorded in subgroup analyses of patients with no comorbidity and in most contemporary patients. The median annual costs of $36,140 and of $47,510 were recorded, respectively in patients treated without and with ADT at RT.

Conclusion

Our findings failed to confirm that combination of ADT at RT reduces CSM rates in high metastatic risk PCa patients aged 80 years or more. Moreover, combination of ADT at RT resulted in a significant cost increase, relative to RT alone.  相似文献   
76.
Regional myocardial perfusion rates were estimated from the myocardial washout of (133)Xenon in 24 patients with heart disease whose coronary arteriograms were abnormal and 17 similar subjects whose coronary arteriograms were judged to be normal. Disappearance rates of (133)Xe from multiple areas of the heart were monitored externally with a multiple-crystal scintillation camera after the isotope had been injected into a coronary artery and local myocardial perfusion rates were calculated by the Kety formula.The mean myocardial perfusion rates in the left ventricle exceeded those in the right ventricle or atrial regions in subjects without demonstrable coronary artery disease. In this group there was a significant lack of homogeneity of local perfusion rates in left ventricular myocardium; the mean coefficient of variation of left ventricular local perfusion rates was 15.8%.In the patients with radiographically demonstrable coronary artery disease, a variety of myocardial perfusion patterns were observed. Local capillary blood flow rates were depressed throughout the myocardium of patients with diffuse coronary disease but were subnormal only in discrete myocardial regions of others with localized occlusive disease. Local myocardial perfusion rates were similar to those found in the group with normal coronary arteriograms in patients with slight degrees of coronary disease and in those areas of myocardium distal to marked coronary constrictions or occlusions which were well supplied by collateral vessels.In subjects with right coronary disease, the mean right ventricular perfusion rates were significantly subnormal; in seven subjects of this group perfusion of the inferior left ventricle by a dominant right coronary artery was absent or depressed. The average mean left ventricular perfusion rate of 12 subjects with significant disease of two or more branches of the left coronary artery was significantly lower than that of the group with normal left coronary arteriograms. In the patients with abnormal left coronary arteriograms, the average coefficient of variation of local left ventricular perfusion rates was significantly increased (24.8%).The studies provide evidence that coronary artery disease is associated with increased heterogeneity of local myocardial perfusion rates. They indicate that radiographically significant vascular pathology of the right or left coronary artery may be associated with significant reductions of myocardial capillary perfusion in the region supplied by the diseased vessel.  相似文献   
77.
Objective: Many studies suggest that age at onset (AAO) is an important factor for clinically differentiating patients with juvenile and adult onset of obsessive–compulsive disorder (OCD). The present international study aimed to assess the prevalence of different AAO groups and compare related socio-demographic and clinical features in a large sample of OCD patients.

Methods: A total of 431 OCD outpatients, participating in the ICOCS network, were first categorised in groups with childhood (≤12 years), adolescent (13–17 years) and adult-onset (≥18 years), then in pre-adult and adult onset (≥18 years) and their socio-demographic and clinical features compared.

Results: Twenty-one percent (n?=?92) of the sample reported childhood onset, 36% (n?=?155) adolescent onset, and 43% (n?=?184) adult onset. Patients with adult onset showed a significantly higher proportion of females compared with the other subgroups (χ2?=?10.9, pχ2?=?11.5; p?Conclusions: The present international multicentre study confirms that OCD onset occurs more frequently before adult age, with approximately one out of five patients showing childhood onset. Pre-adult onset was associated with higher rate of CBT, while adult onset was more prevalent in females.  相似文献   
78.
79.
Objective The objective was to prospectively determine CT density changes in bone metastases, before and after intravenous zoledronic acid for a maximum period of 12 months. Patients and methods Twenty-three consecutive patients presented with bone metastases and underwent therapy with zoledronic acid from December 2004. All patients underwent CT of the chest, abdomen, and pelvis. Bone density, measured in Hounsfield units (HU), was determined by segmenting lesions in the same anatomical area of the metastasis sites on the axial images of the sequential series of CT examinations. The effects of zoledronic acid were evaluated by calculating absolute and relative increases in bone density. Results The patients presented with multiple metastases in 65% of the cases. When compared with the baseline, all groups demonstrated a significant increase in bone density, which significantly (p < 0.01) correlated with the number of zoledronic acid administrations. There was increased bone density of at least 100% in 57%, and an increase of at least 50% in 87% of the patients. This increase was significant in both lytic and sclerotic metastases after 3 months of therapy. No significant bone density difference was found in normal-appearing bone. Conclusion Bone density measured by CT increases at metastatic sites after zoledronic acid treatment, regardless of the type of metastasis, in contrast to apparently normal bone.  相似文献   
80.
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