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91.
We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences.  相似文献   
92.
Twenty-five persons with diabetes (aged 55–83 years) who were living independently in the community, and 40 age- and sex-matched non-diabetic controls were assessed for tactile sensitivity, vibration sense, proprioception, quadriceps strength and body sway. In both men and women, those with diabetes performed significantly worse in tests of body sway on firm and compliant surfaces compared with the control subjects after controlling for weight and body mass index. The female diabetic subjects also performed significantly worse in tests of peripheral sensation and strength compared with controls. Age-related declines in sensori-motor function were greater in the diabetic group (r = 0.55–0.75) than in the controls (r < 0.44), while within the diabetic group, duration of diabetes and vibration sense were significantly correlated with sway on a compliant (foam rubber) surface with the eyes open (partial r = 0.52, p < 0.01 and r = 0.55, p < 0.01, respectively). The study findings provide evidence that older people with diabetes have problems with stability and related sensori-motor factors which may place them at increased risk of falls.  相似文献   
93.
OBJECTIVE: In 1991, a randomized study was published and demonstrated that use of nonsurgical therapy (chemoradiation) provided similar survival to total laryngectomy (the gold standard) for patients with advanced-stage laryngeal cancer. The purpose of this study was to assess how treatment of advanced laryngeal cancer was influenced by such developments in non-surgical therapy. STUDY DESIGN: Patterns of care study using National Cancer Database (1985-2001). RESULTS: The percentage of advanced-stage patients treated with chemoradiation increased from 8.3% to 20.8% while the proportion treated with radiation alone decreased from 38.9% to 23.0%. Use of chemoradiation increased at a significantly faster rate after the 1991 publication at both community cancer centers and teaching research facilities. The use of total laryngectomy decreased slightly during this period. CONCLUSIONS: The use of chemoradiation increased after the 1991 publication. It was impossible to determine from the NCDB whether additional patients who could benefit from chemo-RT were not offered or did not complete this treatment option. We recommend that treatment recommendations discussed at tumor boards be recorded in cancer registries.  相似文献   
94.
Promoting effects of sodium salts of phenobarbital (NaPB) and barbital (NaBB) on the development of bladder tumors were investigated in F344 male rats initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N-nitrosobutyl-4-hydroxybutylamine (BBN). To initiate with FANFT, rats were fed 0.2% FANFT mixed in diet for either 2 or 6 weeks and 2 weeks later were offered diet containing 1000 ppm of NaPB or NaBB. Rats were killed either at 52 or 68 weeks of age. To initiate with BBN, rats were given 0.05% BBN in drinking water for 4 weeks and beginning 1 day later were fed NaBB mixed in diet at 1000 ppm for up to 52 weeks. NaBB promoted bladder carcinogenesis initiated by either FANFT or BBN; the incidence and average number of simple or preneoplastic nodular (PN) hyperplasias, papillomas, and carcinomas per 10 cm of urothelium were significantly increased in the groups receiving NaBB following exposure to FANFT for 6 weeks (p less than 0.05) or BBN for 4 weeks (p less than 0.01). No such effect was seen in rats fed FANFT for only 2 weeks. NaPB also significantly increased (p less than 0.05) the frequency of preneoplastic PN hyperplasias but not the average number of papillomas and carcinomas per 10 cm of urothelium in rats fed FANFT for 6 weeks. NaBB was an effective promoter of bladder carcinogenesis under these experimental conditions, as expected from its known promoting effect on transitional epithelium of the renal pelvis, but NaPB in contrast did not affect the incidence or multiplicity of bladder papillomas or carcinomas under these conditions. NaPB could be considered a promoter for bladder urothelium only by the less rigorous criterion that it increased the frequency of preneoplastic PN hyperplasia.  相似文献   
95.
Methotrexate therapy has been effective in the treatment of RA with short term experience suggesting little serious adverse reactions. Our review of 168 patients receiving methotrexate has identified nine patients with probable or possible methotrexate-induced pulmonary toxicity, giving a prevalence of 5% and an incidence of 3.9 per 100 patients per year. No clinical or laboratory features showed an association that could potentially predict the development of pulmonary disease. All patients experienced complete recovery with supportive care and/or corticosteroid therapy. Clinical monitoring for this complication is warranted in all patients receiving long term methotrexate therapy for RA.  相似文献   
96.
97.
(+)-Hydantocidin, a recently discovered natural spironucleoside with potent herbicidal activity, is shown to be a proherbicide that, after phosphorylation at the 5' position, inhibits adenylosuccinate synthetase, an enzyme involved in de novo purine synthesis. The mode of binding of hydantocidin 5'-monophosphate to the target enzyme was analyzed by determining the crystal structure of the enzyme-inhibitor complex at 2.6-A resolution. It was found that adenylosuccinate synthetase binds the phosphorylated compound in the same fashion as it does adenosine 5'-monophosphate, the natural feedback regulator of this enzyme. This work provides the first crystal structure of a herbicide-target complex reported to date.  相似文献   
98.
The respiratory-dependent pacemaker (RDP3 or MB-1, Biorate, Biotec International, S.p.A., Bologna, Italy) detects the respiratory rate by measuring thoracic impedance using a subcutaneous auxiliary lead. The sensed respiratory rate is used to determine the pacing rate response. This pacemaker had been implanted in 9 patients with a mean age of 58 (range 42-69) years. During symptom-limited treadmill exercise, rate-modulated pacing resulted in a significant increase in pacing rate (mean +/- SD, 124 +/- 10 vs. 71 +/- 3 beats/min p less than 0.001) and exercise capacity (343 +/- 147 vs. 463 +/- 120 s, p less than 0.05) compared to those achieved with constant rate ventricular pacing. Brief treadmill exercise tests showed appropriate rate response to increased walking speed and gradient. However, rate response was modified by arm swinging-induced motion artefact which affected the measured "impedance." Complications observed on follow-up included perforation of the auxiliary lead in 2 patients and symptomatic myopotential interference in 3 patients with the RDP3 pacemaker, all of whom required unit replacement. It is concluded that although the respiratory-dependent pacemaker can confer physiological benefit in patients with bradycardia, myopotential interference (largely overcome by the new version MB-1 with programmable sensitivity) and the auxiliary lead can be problematic in some patients.  相似文献   
99.
Activation of complement by hydroxyl radical in thermal injury   总被引:6,自引:0,他引:6  
K T Oldham  K S Guice  G O Till  P A Ward 《Surgery》1988,104(2):272-279
Complement activation resulting from local burn injury of skin and other soft tissues can be linked to systemic complications, such as intravascular hemolysis, neutrophil activation, and acute lung injury. This study was designed to clarify the relationship between cutaneous thermal injury, oxygen radical formation, and complement activation in vivo. A model for "selective" venous sampling from the area of a partial-thickness cutaneous burn over 25% to 30% of the total body surface in the rat was developed. Interventions involving oxygen radical scavengers, antioxidant enzymes, xanthine oxidase inhibitors, an iron chelator, complement depletion, and neutrophil depletion were used to probe the nature of the oxygen products involved in complement activation. Plasma from the area of burn was examined for total hemolytic complement activity, content of C5a-related chemotactic peptide, and relationship of oxygen products to appearance of this peptide. Xanthine oxidase inhibitors, hydroxyl radical scavengers, and complement depletion diminished the generation of C5a activity at the burn site, whereas neutrophil depletion was without effect. These data suggest that C5a activity may be related to oxygen products from xanthine oxidase. The catalase sensitivity and iron dependency of C5a generation suggest that hydroxyl radical may be related to complement activation and C5a appearance. This is the first report to directly link oxygen radical generation and complement activation in vivo.  相似文献   
100.
Hypoxemia is a nearly constant accompaniment of head injury. Diverse theories have been proposed to explain this relationship. The authors report the case of a patient who suffered an episode of severe, transient, arterial oxygen desaturation during "controlled" brain trauma: an otherwise uneventful stereotaxic biopsy of a small germinoma of the hypothalamus. Evidence is provided that pure ventilation-perfusion mismatching, without pulmonary edema, underlay the hypoxemia. The hypothalamus is intimately involved in matching pulmonary ventilation to perfusion; the hypoxemia of various brain injuries may be mediated by perturbation of this structure.  相似文献   
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