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991.
A Arduini S Dottori AF Sciarroni N Corsico E Morabito E Arrigoni-Martelli M Calvani 《Canadian Metallurgical Quarterly》1995,152(1):31-37
Multiple pulmonary nodules were found in a patient who had an occupational history of coal mining for eleven years and road construction for fifteen years. An open lung biopsy was performed, because nodules had increased in size compared to previous ones and a trasbronchial biopsy was not diagnostic. The nodules were composed of dense concentric lamellar collagenous structures with a serpentine pattern surrounded by an infiltration of histiocytes, lymphocytes and plasma cells with Russel bodies. These findings are compatible with pulmonary hyalinizing granuloma (PHG) named by Liebow A. A. The etiopathogenetic mechanism and the difference between PHG and silicotic nodule is discussed. 相似文献
992.
ED Ames CE Metroka AF Goldberg 《Canadian Metallurgical Quarterly》1993,118(4):313; author reply 313-313; author reply 314
993.
K Nesaretnam N Guthrie AF Chambers KK Carroll 《Canadian Metallurgical Quarterly》1995,30(12):1139-1143
The tocotrienol-rich fraction (TRF) of palm oil consists of tocotrienols and some alpha-tocopherol (alpha-T). Tocotrienols are a form of vitamin E having an unsaturated side-chain, rather than the saturated side-chain of the more common tocopherols. Because palm oil has been shown not to promote chemically-induced mammary carcinogenesis, we tested effects of TRF and alpha-T on the proliferation, growth, and plating efficiency (PE) of the MDA-MB-435 estrogen-receptor-negative human breast cancer cells. TRF inhibited the proliferation of these cells with a concentration required to inhibit cell proliferation by 50% of 180 microgram/mL whereas alpha-T had no effect at concentrations up to 1000 microgram/mL as measured by incorporation of [3H]thymidine. The effects of TRF and alpha-T also were tested in longer-term growth experiments, using concentrations of 180 and 500 microgram/mL. We found that TRF inhibited the growth of these cells by 50%, whereas alpha-T did not. Their effect on the ability of these cells to form colonies also was studied, and it was found that TRF inhibited PE, whereas alpha T had no effect. These results suggest that the inhibition is due to the presence of tocotrienols in TRF rather than alpha T. 相似文献
994.
Previous research suggests that corticotropin-releasing hormone can act in the locus coeruleus to increase the firing of locus coeruleus neurons and elicit physiological responses resembling those associated with stress. The present study used immunocytochemical detection of Fos as a measure of neuronal activation to identify brain areas that were activated by bilateral injections of corticotropin-releasing hormone into the locus coeruleus of rats. Injection of corticotropin-releasing hormone into the locus coeruleus increased the expression of Fos in the locus coeruleus as compared with injection of vehicle into the locus coeruleus or injection of corticotropin-releasing hormone into neighbouring pontine sites. The pattern of Fos expression throughout the brain after injections of corticotropin-releasing hormone into the locus coeruleus was generally consistent with the anatomical organization of efferent projections arising from the locus coeruleus; increased Fos expression was observed in many brain areas including the ventral lateral septum, septohypothalamic nucleus, bed nucleus of the stria terminalis, the central amygdaloid nucleus, the dorsomedial nuclei of the hypothalamus, and the thalamic paraventricular and rhomboid nuclei. Foot shock also increased Fos expression in the locus coeruleus and the other brain regions that expressed Fos after corticotropin-releasing hormone injections into the locus coeruleus. A few brain regions, most notably the hypothalamic paraventricular nucleus, expressed Fos in response to foot shock but not corticotropin-releasing hormone. These results indicate that local injection of corticotropin-releasing hormone into the locus coeruleus stimulates the activity of the locus coeruleus neurons. However, the pattern of Fos expression throughout the brain evoked by injection of corticotropin-releasing hormone into the locus coeruleus does not fully replicate the effects of foot shock. 相似文献
995.
The study of cytotoxic T cell (CTL) responses to measles polypeptides in persons with different HLA frequencies will provide information for the design of new vaccines. Peripheral blood mononuclear cells derived from African blacks and Caucasians were stimulated with measles virus-infected autologous cells and tested in a standard 51Cr-release assay against autologous B cells infected with vaccinia virus recombinants expressing measles virus antigens. The proportion of subjects who generated CTL to the fusion, hemagglutinin, and nucleoprotein antigens was 43%, 38%, and 28%, respectively. The use of HLA-mismatched targets showed killing to be restricted by both HLA class I and class II antigens, although CD8-mediated class I cytotoxicity predominated. Measles vaccine boosted CTL responses in subjects with low initial activity. These data suggest that the fusion and hemagglutinin proteins are important targets for the measles CTL response. 相似文献
996.
PURPOSE: The accuracy of sonourethrography for the evaluation of bulbar urethral strictures has been well documented. Thus, we sought to define the role of preoperative sonourethrography in establishing objective criteria for procedure selection during bulbar urethral reconstruction. MATERIALS AND METHODS: Sonourethrography was performed preoperatively, just before incision, in 67 men selected for bulbar urethroplasty. All patients had strictures 25 mm. or less in length on preoperative radiographic retrograde urethrography, thus potentially amenable to resection and end-to-end anastomosis. Ultrasonic measurements were prospectively recorded, compared with those on preoperative retrograde urethrography, and used to guide the selection of urethroplasty technique. RESULTS: Overall, a significant trend for retrograde urethrography to underestimate stricture length was demonstrated (r = 0.678, p < 0.0001). Indeed, sonographic measurements were frequently twice those of retrograde urethrography, occasionally more. All 26 patients with short strictures on retrograde urethrography (10 mm. or less) were successfully treated by resection and end-to-end anastomosis, and sonographic assessment did not alter management. However, ultrasonic measurement changed the reconstructive procedure selected in 15 of 41 patients (37%, 3 penile flaps, 12 graft procedures) with bulbar strictures of intermediate length on retrograde urethrography (11 to 25 mm.). CONCLUSIONS: Sonourethrography has a major influence on selection of therapy in patients with bulbar strictures of intermediate length. By prospectively identifying strictures too long for resection and end-to-end anastomosis, sonourethrography enables quantitative criteria for selection of patients who may be more appropriately treated by flap or graft procedures. We advocate excisional therapy for strictures appearing sonographically to be 25 mm. or less, and substitution urethroplasty for longer strictures. 相似文献
997.
MC Langereis AJ Bosman AF van Olphen GF Smoorenburg 《Canadian Metallurgical Quarterly》1997,36(5):279-297
The present study addresses the effect of cochlear implantation on vowel production of 20 post-lingually deafened Dutch subjects. All subjects received the Nucleus 22 implant (3 WSP and 17 MSP processors). Speech recordings were made pre-implantation and three and twelve months post-implantation with the implant switched on and off. The first and second formant frequencies were measured for eleven Dutch vowels (monophthongs only) in an h-vowel-t context. Twelve months post-implantation, the results showed an increase in the ranges of the first and second formant frequency covered by the respective vowels when the implant was switched on. The increase in the formant frequency range was most marked for some subjects with a relatively small formant range pre-implantation. Also, at 12 months post-implantation with the implant switched on we found a significant shift of the first and second formant frequency towards the normative values. Moreover, at this time the results showed significantly increased clustering of the respective vowels, suggesting an improvement in the ability to produce phonological contrasts between vowels. Clustering is defined as the ratio of the between-vowel variance of the first and second formant frequency and the within-vowel variance of three tokens of the same vowel. 相似文献
998.
OBJECTIVES: Intracavernosal injection of vasodilating agents has been a mainstay in the treatment of erectile dysfunction. Recently, a transurethral delivery system (MUSE) for alprostadil (prostaglandin E1) was introduced as an alternative form of pharmacotherapy. METHODS: One hundred consecutive patients with erectile dysfunction were treated with MUSE in doses ranging from 125 to 1000 micrograms and their erections were observed in the clinical setting. All patients had previous intracavernosal injections of combination pharmacotherapy (papavarine, Regitine, and/or prostaglandin E1). RESULTS: Of these 100 patients that used MUSE, only 7% had well-sustained, rigid erections while 30% had full erections but with partial rigidity. The remaining 63% of patients did not achieve erections that they thought were adequate for penetration. Penile and/or perineal pain occurred in 24% of patients, 3% had a syncopal episode, and 3% experienced urethral bleeding. One patient had priapism that required drainage. Using intracavernosal injections, 49% had sustained rigid erections, 40% had full erections with partial rigidity, and 11% did not have a response satisfactory for penetration. CONCLUSIONS: These data suggest that intracavernosal injections appear to be more effective than MUSE in achieving a rigid erection in men with erectile dysfunction. 相似文献
999.
AF DiMartini PT Trzepacz KA Pajer D Faett J Fung 《Canadian Metallurgical Quarterly》1997,38(6):565-569
The authors studied 31 liver transplant patients to compare neuropsychiatric side effects of a newer immunosuppressant, FK506, to cyclosporine A (CYA). Patients were randomly assigned to either FK506 or CYA. At the 1-week postoperative stage, cognitive status was assessed with the Mini-Mental State Exam, Trailmaking Tests (TMT) A and B, Delirium Rating Scale, and a neuropsychiatric symptom checklist. No statistically significant differences were found on any outcome variable between these two drugs, though scores on the TMTs were impaired as compared with published norms. The FK506 patients had moderately impaired TMT scores, whereas the CYA patients had only mild impairment. The patients demonstrate good cognitive recovery at 1 week post-transplantation, with only mild evidence of cognitive impairment. 相似文献
1000.
BACKGROUND: Model-based image processing (MBIP) of Doppler E-waves eliminates the need for digitizing waveforms by hand or determining the contour 'by eye'. Little et al. (Circulation 1995, 92:1933-1939) used pressure-volume measurements for dogs to verify the physiologic-model-derived prediction that the left ventricular chamber stiffness, KLV1 can be determined from the deceleration time tdec, when that portion of the E-wave contour is fit by a cosine function. MBIP of clinical Doppler E-wave images to determine chamber stiffness KLV has not been performed. OBJECTIVE: We sought to determine KLV by MBIP of clinical Doppler E-wave images and elucidate the physiologic meaning of the harmonic oscillator filling model's parameter k. METHODS AND RESULTS: The unique mathematical relationship between the kinematic, harmonic oscillator model of filling and KLV predicts that the oscillator's spring constant k be linearly proportional to the chamber stiffness KLV. To verify this, digitally acquired, clinical Doppler transmitral flow velocity images from 21 subjects were analyzed. The parameter k and the stiffness KLV were computed independently for each subject and compared. In accordance with prediction, a linear relationship between k and the stiffness KLV, namely k = 1.16 [A/(rho L)]KLV+41, r = 0.96, was observed. CONCLUSIONS: The oscillator parameter k is linearly proportional to the left ventricular chamber stiffness KLV. The MBIP approach allows automated computation of k and KLV, provides a robust, automated, observer independent method of Doppler transmitral flow velocity analysis, and eliminates the need for visual determination of the contour or measurement of its attributes by eye. It provides a stimulus for further validation of the relationships among K, KLV, and catheterization-based diastolic chamber properties in humans and their correlations with selected diastolic function-altering syndromes. 相似文献