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991.
992.
Pennell RG; Baltarowich OH; Kurtz AB; Vilaro MM; Rifkin MD; Needleman L; Mitchell DG; Mervis SA; Goldberg BB 《Radiology》1987,165(1):79-83
Endovaginal ultrasound (US) was performed in 38 pregnant women at 5-12 menstrual weeks, when the initial transabdominal sonograms had been considered inconclusive or equivocal. Clinical follow-up disclosed 32 intrauterine pregnancies (12 living, 18 spontaneous incomplete abortions, and two embryonic demises) and six ectopic pregnancies. In the 32 intrauterine pregnancies (normal and abnormal), the correct diagnosis was made in all cases with endovaginal US. The endovaginal images demonstrated the intrauterine embryo, its heart motion, and the yolk sac more clearly and more often when these structures were not apparent on the transabdominal scans. Abnormal gestational sacs were better resolved. In the six cases of ectopic pregnancy, while an extrauterine ectopic sac was visualized in only three, absence of an intrauterine gestational sac was confirmed in all cases with endovaginal scanning. No endovaginal study yielded less information than its transabdominal counterpart. Endovaginal sonography is likely to be diagnostic when transabdominal images fail to yield a definitive diagnosis in early pregnancies. 相似文献
993.
本文用微型计算机对在手动式分光光度计上测得的吸收光谱数据进行处理,以导数光谱系数倍率法不经预先分离直接测定小儿退烧片中阿司匹林的含量,方法简便、快速,不需特殊仪器,易于推广。平均百分回收率为99.74±0.46(n=9)。同时还用双波长法测定了另一组分醋氨酚的含量,平均百分回收率为99.54±0.52(n=9)。结果满意,可用于多组分药物制剂的分析。 相似文献
994.
Skin necrosis from intravenously infused materials 总被引:1,自引:0,他引:1
R G Dufresne 《Cutis; cutaneous medicine for the practitioner》1987,39(3):197-198
Skin necrosis from extravasation of intravenous materials can result from nonphysiologic irritants, vasopressors, and chemotherapeutic agents. Careful handling of these materials is essential. Locally infiltrated phentolamine is recommended for accidental vasopressor extravasation. Early surgical excision and repair is recommended for chemotherapeutic infiltrations. General supportive care is recommended for all extravasations. 相似文献
995.
The main objective of the present paper is to report on the concentration of silicon carbide (SiC) fibres, crystalline silica and respirable dust in a Canadian SiC production plant and to compare the results with earlier investigations. The second objective is to tentatively explain the differences in concentration of the fibrogenic substances between different countries. The assessment of SiC fibres, dusts, respirable quartz and cristobalite was performed according to standard procedures. The highest 8 h time-weighted average concentrations of fibres were found among the crusher and backhoe attendants and the carboselectors with an arithmetic mean of 0.63 fibres ml(-1) for the former group and 0.51 fibres ml(-1) for the latter group. The results of respirable SiC fibres in the Canadian plant were lower than in the Norwegian and Italian industries. Most of the 8 h time-weighted average concentrations for quartz were less than or around the limit of detection of 0.01 mg m(-3). The maximum 8 h time-weighted average concentration for quartz was found among the carboselectors (0.157 mg m(-3)), followed by the labourers (0.032 mg m(-3)). Similarly, most of the 8 h time-weighted average cristobalite measurements were less than the limit of detection of 0.01 mg m(-3) except for the carboselectors where it was found to be 0.044 mg m(-3). The assessment of the Italian occupational settings exposure demonstrated elevated quartz concentrations, while cristobalite was absent. The authors have concluded that the investigations that were performed in the last two decades in this field by researchers from different countries seem to support that SiC fibres (whiskers) constitute a major airborne health hazard. 相似文献
996.
997.
The mediastinal vessels in 27 patients who had previously undergone vascular surgery were evaluated with use of magnetic resonance (MR) imaging for patency and the presence of stenosis. Thirty-six postoperative vessels or shunts were studied, including 11 aortas after coarctation or stenosis repair, 18 systemic-pulmonary shunts, four pulmonary artery or vein repairs, and three spiral vein grafts. Angiographic (n = 21), direct surgical (n = 1), contrast material-enhanced computed tomography (n = 1), or clinical (n = 13) findings were correlated with the MR findings. Overall, the accuracy of MR imaging for determination of patency was 100%. In patients with angiographic correlation and technically adequate MR examinations, MR imaging results were used to identify or exclude stenoses correctly in 66.7% of patent vessels. The four missed or underestimated stenoses occurred in vessels 10 mm or less in diameter. 相似文献
998.
Glazer HS; Niemeyer JH; Balfe DM; Devineni VR; Emami B; Hayden RE; Aronberg DJ; Levitt RG; Ward MP; Sagel SS 《Radiology》1986,160(2):343-348
Untreated neoplasms of the neck (tumors of the oropharynx, supraglottic area, carotid body, and thyroid, in addition to malignant lymphadenopathy) were evaluated in 23 patients with magnetic resonance (MR) imaging. The results were compared with computed tomographic (CT) scans in 20 patients. Contrast between tumor and fat was best on relatively T1-weighted images (500/30-35 [TR msec/TE msec]), whereas separation of tumor and muscle was best with relatively T2-weighted pulse sequences (1,500/90). Balanced images (1,500/30-35) provided best overall image quality and best demonstrated vascular anatomy. MR imaging was usually superior to CT in showing the relationship of tumor mass to muscle. MR imaging and contrast material-enhanced CT were equivalent in most patients in defining vascular anatomy, but MR imaging was superior when intravenous contrast material was not administered. However, CT was more helpful in showing bone and cartilage anatomy, and in some patients CT also was better in showing airway abnormalities. Despite these limitations, MR imaging is a promising imaging technique for studying neoplasms of the neck. 相似文献
999.
Nayebzadeh A Case BW Massé J Dufresne A 《International archives of occupational and environmental health》2006,79(3):227-236
Objectives: Lung fibre content was determined for 86 former chrysotile miners and millers in two Québec mining regions: Thetford mines (TM) and the Asbestos region (AR). Methods: Fibres were assessed using transmission electron microscopy (TEM) and energy dispersive X-ray spectrometry (EDS). Asbestos body (AB) concentrations were assessed by microscopy of tissue digests. Corresponding histological lung tissue sections were quantitatively graded for the severity of interstitial fibrosis on a 12-point scale. Fibrosis score and its associations with (1) fibre concentrations and fibre dimensions within three fibre length intervals (less than 5 μm, 5–10 μm, and over 10 μm), and (2) several exposure variables were evaluated using correlation coefficients and regression techniques. Results: Concentration of short (<5 μm) tremolite fibres was the best predictor of fibrosis grade in both mining groups (r=0.44, P<0.01 and r=0.39, P<0.01 for TM and AR, respectively). Chrysotile fibre concentration showed a lower correlation with the fibrosis grade for subjects from TM only. Long (>10 μm) amosite fibre concentration showed a linear relationship with the fibrosis score in miners and millers from AR. Exposure variables, including smoking, had no predictive value for fibrosis grade. Within fibre length categories, fibre dimension was not related to the fibrosis score. Conclusion: Lung fibre concentration as measured by TEM/EDS, especially that of short (<5 μm) tremolite fibres, is a better predictor of fibrosis grade in these two groups of chrysotile miners than either the concentration of ABs or the duration of exposure. Due to the limitation of our counting method, almost all fibres longer than 10 μm observed in this study were shorter than 14 μm. Thus, if length plays a role in fibrogenesis, it may be related to fibres of greater length than those covered in this study. 相似文献
1000.
Redondo L Brown R Fernández A Chacón J Martínez-Parra C 《Neurología (Barcelona, Spain)》2002,17(2):77-84
Background: Bradykinesia is the clinical feature of Huntington's disease most closely related to functional discapacity and stage, probably as a consequence of spreading of neuronal injury. The aim of the present article is to verify whether a choice reaction time could be considered an estimate measurement of clinical bradykinesia, and its possible relationships with other evolutive parameters such as functional discapacity, clinical stage and prefrontal executive dysfunction.Methods: Fifteen patients were studied (9 in advanced stage and 6 initials), equal number of controls and 3 asymptomatic gene carriers. We used clinical bradykinesia and functional capacity scales, an extensive prefrontal battery and a computerized paradigm of reaction time.Results: Clinical bradykinesia and reaction time are closely related. The associations between reaction time with those parameters indicatives of prefrontal dysfunction, functional discapacity and clinical stage are closer and more significatives than those that could be established with clinical bradykinesia.Conclusions: Reaction time is an objective measurement of global motor slowness that allow us assigning each subject to a specific stage, and avoid possible errors derived from interobserver bias in clinical scales. 相似文献