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81.
K Fujinaga TP Cujec J Peng J Garriga DH Price X Gra?a BM Peterlin 《Canadian Metallurgical Quarterly》1998,72(9):7154-7159
82.
J Weinzweig PL Schnur JP McConnell JB Harris PM Petty TP Moyer D Nixon 《Canadian Metallurgical Quarterly》1998,101(7):1836-1841
The silicone breast implant controversy rages on. Recent work has demonstrated that normal or baseline breast tissue silicon levels in women who had had no prior exposure to any type of breast implant may be as high as 446 microg/gm of tissue. These data ranged from 4 to 446 microg/gm of tissue, with a median of 27.0 microg/gm of tissue. In addition, numerous other epidemiologic and rheumatologic studies have demonstrated no association between silicone breast implants and any connective-tissue diseases. Despite these reports, the use of silicone implants remains restricted. The present study measured breast and capsular tissue silicon levels from 23 breasts in 14 patients with saline implants, and from 42 breasts in 29 patients with silicone implants. No patient in the saline implant group presented with signs or symptoms of connective-tissue disease. Patients with silicone implants, however, were divided into three groups based on the presence or absence of signs or symptoms of connective-tissue disease: group I, no symptoms or signs; group II, + symptoms, no signs; and group III, + symptoms, + signs. Six patients in group III were diagnosed with a specific connective-tissue disease, including systemic lupus erythematosus, rheumatoid arthritis, or scleroderma. The most common indications for implant removal or exchange were capsular contracture and implant rupture, although 41 percent of patients with silicone implants expressed media-related concern over the implant issue. The most common symptoms described by patients in groups II and III were joint pain and stiffness, arm pain and numbness, and fatigue. In all groups, capsular tissue silicon levels were significantly greater than breast tissue levels. This finding may indicate that the capsule serves as a barrier to the distribution of silicone from the implant into adjacent breast tissue. Although breast tissue silicon levels in patients with silicone implants were not significantly greater than those in patients with saline implants (p = 0.48), capsular tissue levels in patients with silicone implants were, indeed, significantly greater than those in patients with saline implants (p < 0.001). However, no statistically significant differences in tissue silicon levels were observed with relation to the presence or absence of connective-tissue disease signs or symptoms in patients with silicone implants (groups I to III). Therefore, these data strengthen the conclusion that there is no association between tissue silicon levels and connective-tissue disease. 相似文献
83.
84.
LI Tsao B Ladenheim AM Andrews CC Chiueh JL Cadet TP Su 《Canadian Metallurgical Quarterly》1998,287(1):322-331
Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical. 相似文献
85.
We describe an example of a rare benign intranodal haemorrhagic spindle cell tumour (also called intranodal myofibroblastoma), occurring in a lymph node of the right inguinal region of a 53 year-old male patient. This is the first documentation of this tumour in the Danish literature. The lesion presents typically as a unilateral, solitary, painless inguinal lump. The microscopic appearance is characterized by proliferating spindle-shaped cells, interstitial haemorrhage and amianthoid fibers. Differential diagnosis includes primary and secondary lymph node tumours, such as Kaposi's sarcoma; metastatic spindle cell carcinoma; melanoma; neurilemmoma and soft tissue sarcomas. The clinical behaviour of the tumour is benign and local excision is the treatment of choice. 相似文献
86.
87.
OBJECTIVE: To determine the efficacy of acarbose, compared with placebo, on the metabolic control of NIDDM patients inadequately controlled on maximal doses of conventional oral agents. RESEARCH DESIGN AND METHODS: In this three-center double-blind study, 90 Chinese NIDDM patients with persistent poor glycemic control despite maximal doses of sulfonylurea and metformin were randomly assigned to receive additional treatment with acarbose 100 mg thrice daily or placebo for 24 weeks, after 6 weeks of dietary reinforcement. Efficacy was assessed by changes in HbA1c, fasting and 1-h postprandial plasma glucose and insulin levels, and fasting lipid levels. RESULTS: Acarbose treatment was associated with significantly greater reductions in HbA1c (-0.5 +/- 0.2% vs. placebo 0.1 +/- 0.2% [means +/- SEM], P = 0.038), 1-h postprandial glucose (-2.3 +/- 0.4 mmol/l vs. placebo 0.7 +/- 0.4 mmol/l, P < 0.001) and body weight (-0.54 +/- 0.32 kg vs. placebo 0.42 +/- 0.29 kg, P < 0.05). There was no significant difference between the two groups regarding changes in fasting plasma glucose and lipids or fasting and postprandial insulin levels. Flatulence was the most common side effect (acarbose vs. placebo: 28/45 vs. 11/44, P < 0.05). One patient on acarbose had asymptomatic elevations in serum transaminases that normalized in 4 weeks after acarbose withdrawal. Another patient on acarbose developed severe hypoglycemia; glycemic control was subsequently maintained on half the baseline dosage of sulfonylurea. CONCLUSIONS: In NIDDM patients inadequately controlled on conventional oral agents, acarbose in moderate doses resulted in beneficial effects on glycemic control, especially postprandial glycemia, and mean body weight. Additional use of acarbose can be considered as a useful alternative in such patients if they are reluctant to accept insulin therapy. 相似文献
88.
Emergency physicians need to understand the potential for false reassurance in the interpretation of reflex examination data. Neurologic consultation should be sought when classic signs are lacking, but other evidence causes suspicion. Changes in teaching emphasis and acute practice are needed, since the stakes may be high and time is of the essence. We have responded to the insights gained from this study by augmenting in-service and continuing medical education teaching and by implementing guidelines to assist EPs. We have emphasized the importance of spotlighting high-risk patients, as exemplified above, and of taking advantage of neurologic or neurosurgical consultation. Where in-person consultation is less available, the use of guidelines and remote consultation should be able to help direct further examination, diagnostic formulation, and the need for imaging decisions. Given the potential for severe negative outcome if spinal emergencies are not optimally managed, we must give the teaching of these issues high priority. 相似文献
89.
GH Westrich ML Allen SJ Tarantino B Ghelman R Schneider RS Laskin SB Haas TP Sculco 《Canadian Metallurgical Quarterly》1998,(356):125-133
The efficacy of ultrasound compared with ascending venography for the detection of deep venous thrombosis immediately after total knee arthroplasty was assessed after a 2-year interval. One hundred thirty-seven patients were eligible for the study; however, 31 patients received only one of the screening methods and a color Doppler examination was inconclusive in six patients. Therefore, 100 patients had a Doppler examination and a venogram. Overall, the sensitivity of ultrasound was 85%, the specificity 97%, the positive predictive value 85%, the negative predictive value 97%, and the accuracy 95%. The sensitivity in the calf was 83%, in the popliteal vein 86%, and in the femoral vein 100%. Two years ago, the initial assessment of ultrasound for the detection of deep venous thrombosis after surgery in patients who had total joint arthroplasty revealed a 75% sensitivity, 99% specificity, 91% positive predictive value, 97% negative predictive value, and 97% accuracy. The sensitivity in the calf was 83%; the sensitivity in the popliteal vein was 40%; and the sensitivity in the femoral vein was 50%. After 2 years of using this screening test with one technician and one radiologist, an improvement with this noninvasive technique was shown. However, it was found that Doppler imaging is not as sensitive as venography for detecting calf thrombi. Any imaging technique should be validated by each institution to determine the validity of the instrument and the learning curve of the technician administering the examination. 相似文献
90.
AN Viktorov ND Novikova EA Deshevaia MP Bragina AV Shnyreva TP Sizova IuT D'iakov 《Canadian Metallurgical Quarterly》1998,32(5):57-62
Results of many years of the survey of highly specific evolution of quantitative and species composition of microflora of the MIR environment are reviewed. Analysis of the data enabled listing of microorganisms-declinous fungi with the ability of residential colonization of structural materials of the interior and equipment of habitable modules of the space station. Results of the studies of variability and level of similarity/affinity on the basis of DNA, polymorphism of strains isolated in space flight, convincingly confirmed this characteristic in the Penicillium chrysogenum cultures. In view of the common origin determined from the signs of genetic alliance, the P. chrysogenum strains isolated on MIR in 1995 can be considered descendants of the cultures found at the beginning of the MIR operation. This ecological expansion of P. chrysogenum in the space station environment gains in prominence due to the fact that representative of this particular species known for its active biodestructive nature were, as a rule, detected in the areas where structural materials of the SALYUT and MIR space stations incurred biological degradation. 相似文献