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31.
Postoperative radiotherapy for locally advanced colon cancer   总被引:1,自引:0,他引:1  
Background: The role of adjuvant postoperative radiotherapy for locally advanced colon cancer is not well documented. Methods: Seventy-eight patients who underwent a complete resection of B2-C colon cancer received postoperative radiotherapy. Twenty-eight patients received ⩽45 Gy; 50 patients received 50–55 Gy. Twenty-seven patients received adjuvant fluorouracil-based chemotherapy. All patients were followed for a minimum of 3 years; no patients were lost to follow-up. Results: The overall local control rate was 88%. The 5-year actuarial rate of local control was 96% after 50–55 Gy postoperative radiotherapy compared with 76% after <50 Gy (p=0.0095). Multivariate analysis of local control showed that only radiotherapy dose significantly influenced this end point. Cause-specific survival rates at 5 years were B2, 67%; B3, 90%; C1, 100%; C2, 61%; C3, 36%; and overall, 63%. Multivariate analysis of cause-specific survival showed that only stage significantly influenced this end point. Bowel obstruction caused by adhesions developed in three patients and required a laparotomy; radiation-induced sarcoma developed in one additional patient. Conclusions: Postoperative radiotherapy appears to reduce the risk of local recurrence in patients with locally advanced colon cancer. The optimal dose is probably 50–55 Gy at 1.8 Gy per fraction. Postoperative radiotherapy may improve cause-specific survival for patients with stages B3 and C2 cancers.  相似文献   
32.
The purpose of this study was to examine the correlates of post-shelter maternal family satisfaction in a group of youth who were reunified with their families following a shelter stay. Findings indicated that higher ratings of family satisfaction were related to greater maternal problem solving skill and less family conflict.  相似文献   
33.
Newer electrodiagnostic techniques in peripheral nerve injuries   总被引:5,自引:0,他引:5  
Careful attention to technique is essential for the accurate evaluation of peripheral nerve function using conventional EMG and nerve conduction studies. Numerous technical, anatomic, and physiologic pitfalls must be avoided. The amplitudes of the M wave and SNAP contain useful diagnostic information and should be evaluated carefully in addition to conduction velocity and distal latency. Newer techniques using the F wave, H reflex, SEP, dermatomal SEP, and quantitative EMG may be helpful in evaluation of selected peripheral nerve problems. Comparative nerve conduction studies using "inching" technique permit evaluation of short nerve segments. Comparisons with parallel nerves improve diagnostic sensitivity.  相似文献   
34.
The "Learn Not to Burn" prevention program is a burn prevention curriculum sponsored by the North Carolina Jaycee Burn Center, the State Department of Public Instruction, and the North Carolina Department of Insurance Fire and Rescue Division. The goal of the program is to reduce burn-related deaths and injuries in North Carolina through burn prevention education by making the "Learn Not to Burn" curriculum available to primary school children across the state at no cost to the schools. The curriculum instrument is a reusable notebook that provides a means for teachers to integrate burn prevention into regular class subject areas. At the time of initiation of this study approximately 70% of the school systems in North Carolina had been provided with the "Learn Not to Burn" curriculum.  相似文献   
35.
Since previous studies showed that calcium uptake by synaptosomes from rodents declines with aging [30], the subsynaptosomal distribution of calcium was determined with the disruption method of Scott et al. [37]. Calcium uptake by the mitochondrial (digitonin-resistant) and non-mitochondrial (digitonin-labile) compartments, as well as total uptake, were determined at 2, 5 and 10 min. After a 10 min incubation under resting conditions (5 mM-KCl), total calcium uptake decreased at 10 months (−14.6%) and 30 months (−33.0%) of age; mitochondrial calcium uptake increased by 10 months (+11.2%) but declined by 30 months (−17.5%); the nonmitochondrial calcium compartment declined at 10 (−34.7%) and 30 (−43.4%) months when compared to the 3 month old control. With potassium depolarization (31 mM-KCl), total calcium uptake declined from 100% (3 months) to 73.8% (10 months) or 53.0% (30 months); mitochondrial calcium uptake declined from 100% (3 months) to 85.6% (10 months) or 68.4% (30 months); non-mitochondrial calcium uptake decreased at 10 (−34.3%) and 30 (−57.7%) months of age when compared to 3 months (100%). The deficits in calcium homeostasis are not due to changes in synaptosomal volumes or to diminished membrane potentials, as assessed by tetraphenylphosphonium ion accumulation. 3,4-Diaminopyridine partially reversed the alterations in total, mitochondrial and non-mitochondrial calcium uptake by synaptosomes from aged mice.  相似文献   
36.
Latencies of normal and adapted feline vestibulo-ocular reflex (VOR) were studied in five cats by applying ± 20°/s horizontal head velocity steps (4000°/s2 acceleration) and measuring the elicited horizontal or vertical reflex eye responses. Normal VOR latency was 13.0 ms ± 1.9 SD. Short-term adaptation was then accomplished by using 2 h of paired horizontal sinusoidal vestibular stimulation and phase-synchronized vertical optokinetic stimulation (cross-axis adaptation). For long-term adaptation, cats wore ×0.25 or ×2.2 magnifying lenses for 4 days. The cats were passively rotated for 2 h/day and allowed to walk freely in the laboratory or their cages for the remainder of the time. The latency of the early (primary) adaptive response was 15.2ms±5.2 SD for crossaxis adaptation and 12.5 ms±3.9 SD for lens adaptation. This short-latency response appeared within 30 min after beginning the adaptation procedure and diminished in magnitude overnight. A late (secondary) adaptive response with latency of 76.8 ms±7.0 SD for cross-axis adaptation and 68.1 ms±8.8 SD for lens adaptation appeared after approximately 2 h of adaptation. It had a more gradual increase in magnitude than the primary response and did not diminish in magnitude overnight. These data suggest that brainstem VOR pathways are a site of learning for adaptive VOR modification, since the primary latency is short and has a similar latency to that of the normal VOR.  相似文献   
37.
The initial effects of diazoxide on dynamic pulmonary compliance (CL) and flow resistance (RL) were measured in paralyzed, anesthetized guinea-pigs. Diazoxide (10, 20 or 40 mg/kg) caused a dose-related increase in RL and decrease in CL. The increase in RL could be selectively abolished by glossopharyngealotomy or decentralization, and by pretreatment with mepyramine (0.1 mg/kg) or disodium cromoglycate (10 mg/kg). Pretreatment with indomethacin (0.1 mg/kg) or acetylsalicylic acid (1 mg/kg) selectively eliminated the decreases in compliance observed after diazoxide. It is concluded that diazoxide initially constricts both large (RL) and small (CL) airways. The constriction of the large airways may involve a release of histamine, whereas the constriction of the small airways may be mediated by a prostaglandin or prostaglandin-like substance.  相似文献   
38.
Research over the past decade has provided a new understanding of genital herpes transmission and measures that can reduce transmission risk. It is unclear, however, how those affected by genital herpes access and interpret this information to make decisions about risk behaviours. This study measured how people with genital herpes and their partners perceived prevention methods, barriers and facilitating factors, and information sources. Formative evaluation was conducted, and survey data were collected from visitors to four websites (n=1849). Results suggest that the prevention messages of refraining from sex during disease outbreaks and condom use have had the greatest reach. Misconceptions about the potential role of suppressive antiviral therapy for genital herpes prevention persist among a substantial percentage of respondents. Accurate information concerning transmission between outbreaks, the effectiveness of condoms and the role of antiviral medication is critical in preventing the spread of genital herpes.  相似文献   
39.
The Mycotrim-GU (Hana Biologics, Berkeley, Calif.) biphasic culture system and a conventional system were compared for their ability to detect Ureaplasma urealyticum and Mycoplasma species in 100 clinical specimens. Both systems detected 18 Mycoplasma spp. isolates. The average colony detection time was 1.9 days with the Mycotrim-GU and 2.3 days with the conventional system. The Mycotrim-GU agar detected all 33 U. urealyticum isolates recovered in the study, and the conventional agar detected 31. In addition to the U. urealyticum isolates recovered from the agar, there were several specimens that, although they did not grow colonies on the agar, gave an alkaline broth change. Of these specimens, two were found with the conventional system and seven were found with the Mycotrim-GU. The average detection time of U. urealyticum colonies was 2.0 days for the conventional agar and 1.7 days for the Mycotrim-GU. The Mycotrim-GU offers several advantages over the conventional system: it is commercially available, consists of a one-flask system which is ready to use, has a significantly longer shelf life, and is cost competitive. This study showed the Mycotrim-GU to be an effective system for detecting the genital mycoplasmas.  相似文献   
40.
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