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41.
42.
A retrospective clinical review of 100 consecutive patients with extremity sarcomas managed by limb salvage operations was performed to evaluate local tumor control and morbidity. The mean follow-up period was 45.1 months. Overall survival was 86%. There were local recurrences in 3% of patients, and 26 complications in 22 patients. Wound necrosis was the most frequent complication. Failure of allogeneic bone graft operations occurred in 25 patients. Most of the complications were salvageable without loss of limb. Limb salvage is an acceptable surgical treatment of extremity sarcomas based on adequate local control and minimal morbidity.  相似文献   
43.
A J Finnimore  R V Jackson  A Morton    E Lynch 《Thorax》1994,49(1):66-70
BACKGROUND--Tiredness and daytime respiratory failure occur frequently in myotonic dystrophy. Sleep hypoxaemia was studied in 12 patients with myotonic dystrophy and correlations were sought with their daytime lung and respiratory muscle function. METHODS--All patients underwent overnight sleep studies, clinical assessment, measurement of flow-volume loops and carbon monoxide transfer factor, arterial blood gas analysis, and physiological assessment of both thoracic muscle function and upper airways obstruction. RESULTS--The mean nadir of oxygen saturation during sleep was 75% (95% confidence interval 69% to 81%). A mean of 3.4% of total sleep duration was spent at an oxygen saturation level below 85%. Five of the 12 patients had an apnoea index of > 5, the group mean apnoea/hypopnoea index being 15.8 events/sleep hour. The mean awake arterial oxygen tension (PaO2) was 10.7 kPa. There was a trend to hypercapnoea with a mean awake arterial carbon dioxide tension of 6.1 kPa; carbon dioxide retention worsened during sleep. Respiratory muscle dysfunction was mainly evident as a low maximum expiratory mouth pressure. Upper airway obstruction assessed by physiological criteria was found in four of the 12 patients. The proportion of total sleep duration with oxygen saturation levels below 85% was directly related to body mass index (weight/height2) and inversely related to the awake PaO2. Body mass index was inversely related to the overnight nadir of oxygen saturation. CONCLUSIONS--Patients with myotonic dystrophy are often hypoxic during sleep and the subgroup that are obese, or have symptoms of sleep apnoea, or both, are particularly at risk. Sleep studies should be considered in this subgroup of patients with myotonic dystrophy.  相似文献   
44.
A tiered testing strategy has been developed to evaluate the potential for new ingredients, tobacco processes, and technological developments to alter the biological activity that results from burning tobacco. A series of studies was initially conducted with cigarettes containing 3% high fructose corn syrup (HFCS) as an alternate tobacco casing material to corn syrup/invert sugar, including determination of selected mainstream cigarette smoke (MS) constituent yields, Ames assay, sister chromatid exchange (SCE) assay in Chinese hamster ovary (CHO) cells, a 30-week dermal tumor-promotion evaluation of cigarette smoke condensate (CSC) in SENCAR mice, and a 13-week subchronic inhalation study of MS in Sprague-Dawley rats. A second series of studies was conducted with cigarettes containing 3%, 4% and 5% HFCS including MS chemistry, Ames assay, SCE assay in CHO cells, and a neutral red cytotoxicity assays. Collectively, mainstream smoke chemistry, genotoxicity, dermal tumor-promotion, and inhalation toxicity studies demonstrated no differences between cigarettes with 3% HFCS and cigarettes with 3% corn syrup/invert sugar. Also, mainstream smoke chemistry and genotoxicity of cigarettes with 4% and 5% HFCS were not different from cigarettes with 3% HFCS. In conclusion, the addition of up to 5% HFCS to cigarette does not alter the mainstream smoke chemistry or biological activity of mainstream smoke or mainstream smoke condensate as compared to cigarettes with 3% corn syrup/invert sugar with regard to the parameters investigated and presented.  相似文献   
45.
Morton I. Hyson  MD 《Headache》1998,38(6):475-477
This study was performed to determine the efficacy of an anticephalgic photoprotective premedicated mask in the treatment of migraine and/or tension-type headaches. There were 54 patients. They were given masks and numbered bottles of topical medication containing either salicin or placebo. The patients were instructed to apply the medication to their frontalis region in the event they should suffer a headache, apply a photoprotective mask, and lie down. Furthermore, they were instructed to take their usual oral or parenteral medications, if required, for relief of the headache. They subsequently filled out forms rating the degree of relief which they attributed to the topical medications and the masks using a 0 to 10 scale. They were also simply asked if this form of treatment helped or not.
Seven of the 20 patients receiving placebo stated the medication and mask helped. The placebo group rated the treatment an average of 4.31 on a 0 to 10 scale. Twenty-eight of 34 patients receiving salicin stated it was effective. The salicin group rated it 7.42 on a 0 to 10 scale ( P <0.001). The majority of the salicin patients stated the duration of their headaches was significantly reduced, as was their need for analgesic and/or narcotic medications.
This study demonstrates a significant difference between placebo and salicin in association with the photoprotective mask in treating migraines and/or tension-type headaches with associated frontalis pain and photophobia.  相似文献   
46.
47.
The widely used DSM-III criteria for the diagnosis of bulimia essentially define bulimia as a syndrome of guilty, secretive and subjectively hard to control binge over-eating. A self-report questionnaire for bulimic behavior was administered to three community and two hospital populations in South Australia. 13% of females in the community samples could be categorized as bulimic according to the DSM-III criteria. Those criteria did not adequately define the behaviour of patients in treatment for bulimia in a Weight Disorders Unit, 85% of whom not only binged, but induced vomiting afterwards. When diagnostic criteria were more closely aligned to clinical experience, the prevalence of bulimia in the community appeared closer to 1-2%. New DSM criteria (DSM-III-R) have been proposed and prevalence rates using them fell within the 1-2% range.  相似文献   
48.
Somatostatin: evidence for a role in thermal nociception   总被引:5,自引:0,他引:5  
In barbiturate-anaesthetized spinalized cats, antibody microprobes were used to investigate the release of immunoreactive somatostatin (irSS) in the lumbar dorsal horn in response to cutaneous stimuli. In the absence of applied stimulation, a significant basal release of irSS was present in the region of the substantia gelatinosa. Such release was not increased by innocuous or noxious cutaneous mechanical stimuli nor by innocuous thermal stimuli, but was increased by noxious thermal stimulation. The magnitude of this noxious heat-evoked release was estimated by comparing in vivo microprobes with those used to detect known concentrations of somatostatin in vitro. Pairs of microprobes were used to detect simultaneous release of both irSS and immunoreactive substance P in the substantia gelatinosa. The results support the putative role of somatostatin in the spinal transmission of thermal nociceptive information.  相似文献   
49.
50.
The exposures of building maintenance personnel and occupants to airborne asbestos fibers, and the effects of operations and maintenance programs on those exposures, continue to be an important public health issue. The subject of this investigation was a large metropolitan county with numerous public buildings which routinely conducted air sampling for asbestos. A total of 302 personal air samples in nine task categories collected during maintenance worker activities in proximity to asbestos-containing materials were analyzed; 102 environmental air samples in four task categories were also analyzed. The arithmetic means of the 8-hr time weighted average exposures for personal sampling for each task category were all below the Occupational Safety and Health Administration permissible exposure level of 0.1 fibers (f)/cc > 5 μm. The highest mean 8-hr time weighted average exposure was 0.030 f/cc > 5 μm for ceiling tile replacement. The maximum asbestos concentration during sample collection for environmental samples was 0.027 f/cc > 5 μm. All asbestos-related maintenance work was done within the framework of an Operations and Maintenance Program (OMP) which utilized both personal protective equipment and controls against fiber release/dispersion. Results are presented in association with specific OMP procedures or controls. These results support the effectiveness of using Operations and Maintenance Programs to manage asbestos in buildings without incurring unacceptable risk to maintenance workers performing maintenance tasks.  相似文献   
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