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91.
92.
冬虫夏草对小鼠巨细胞病毒感染的作用 总被引:9,自引:0,他引:9
目的:观察冬虫夏草多糖脂蛋白(Ⅰ)和Ⅰ+黄芪(Ⅱ)对小鼠巨细胞病毒(MCMNV)感染的作用。方法:将不同浓度Ⅰ、Ⅱ和淫羊藿(Ⅲ)接种在鼠胚成纤维细胞(MEFC)上,观察毒性作用;将Ⅰ、Ⅱ与MCMV等量混匀后,接种MEFC培养瓶,观察Ⅰ、Ⅱ对MCMV的作用;预先igⅠ和Ⅱ15d后,接种MCMV。d6取唾液腺标本接种MEFC,培养后观察Ⅰ、Ⅱ以 液腺标本接种MEFC后的MCMV分离数目,结果:1除Ⅲ外 相似文献
93.
KM RAI KJ PHILIPOSE VSM P TAKKAR RR BHONDE KK MAUDAR NK PANICKER 《Medical Journal Armed Forces India》1999,55(2):119-122
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts 相似文献
94.
HER-2 gene amplification and protein overexpression has been associated with increased risk of advanced-stage breast cancer and poor prognosis. Recently, a single missense point mutation (Ile(655)Val) in the transmembrane domain of the HER-2 gene was associated with a 40% increase in breast cancer risk among women 45 years of age and younger. In this analysis, we measured the association between the Ile(655)Val variant and postmenopausal breast cancer among women participating in the Hawaii and Los Angeles Multiethnic Cohort. Risk of localized breast cancer was significantly elevated among women with the HER-2 variant, but not among women with regional or metastatic disease. Women with at least one copy of the Valine variant were approximately one-half as likely to have high-stage as low-stage breast cancer (P =.02), and this effect was present across racial/ethnic groups. 相似文献
95.
Limb allotransplantation in the rat: extended survival and return of nerve function with continuous cyclosporin/prednisone immunosuppression 总被引:1,自引:0,他引:1
We report the variability of the rejection process among the several tissues of a limb allograft. We used a rat hind limb allograft model transplanting across a well-defined minor histocompatibility barrier (Fischer RT-1(1v1)), donor animals, and Lewis (RT-1(1)) recipient animals. Continuous cyclosporin and prednisone immunosuppression was used. Four immunosuppressive regimens all produced extended limb survival. The rejection process was most severe and difficult to control in the skin. Nonskin tissues reverted to a nearly normal appearance after a period of cellular infiltration 2 to 3 weeks posttransplantation. Clinical and electromyographic evidence of nerve regeneration and end-organ reinnervation was demonstrated in long-term surviving animals. 相似文献
96.
G A Press J W Murakami E Courchesne M Grafe J R Hesselink 《AJR. American journal of roentgenology》1990,154(3):593-602
Thin (5-mm) coronal high-field (1.5-T) MR images of four human brain specimens and 14 normal volunteers were correlated with myelin-stained microtomic sections of the specimen cerebella. The primary white-matter tracts innervating several hemispheric (posterior quadrangular, superior, and inferior semilunar, gracile, biventer, tonsil) and vermian (declive, folium, tuber) lobules are oriented perpendicularly to the coronal plane of section and are shown well on proton-density-weighted (long TR/short TE) and T2-weighted (long TR/long TE) spin-echo images, which provide excellent contrast between gray and white matter. Several of the surface sulci and fissures of the cerebellar hemispheres (including the superior posterior, horizontal, secondary, and posterolateral fissures) also course perpendicular to the coronal plane and are depicted well on T1-weighted (short TR/short TE) and T2-weighted images, which maximize contrast between CSF and parenchyma. The opportunity for side-to-side comparison of the hemispheres is a distinct advantage of the coronal view. Nevertheless, more obliquely oriented surfaces (preculminate, primary, inferior posterior, inferior anterior, and intrabiventral fissures) and deep hemispheric structures (primary white-matter tracts to central, anterior quadrangular, and floccular lobules) may be obscured by volume-averaging in the coronal plane; moreover, much of the finer anatomy of the vermis is depicted poorly. The constant surface and deep anatomy of the cerebellum revealed on coronal images in normal volunteers encourages detailed mapping. MR imaging in the coronal plane should be especially useful in identifying, localizing, and quantifying normal and abnormal morphologic differences between the cerebellar hemispheres. 相似文献
97.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns. 相似文献
98.
99.
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography. 相似文献
100.