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1.
Morganella morganii postoperative endophthalmitis 总被引:1,自引:0,他引:1
2.
In a previous study we have demonstrated that endogenous neurotrophin 3 (NT3) is required for the survival of most sympathetic neurones in postnatal rats. However, the mechanisms underlying the action of NT3 on sympathetic neurones is not known. Neither is it understood whether NT3 is retrogradely transported from peripheral tissues or acts locally in an autocrine fashion. In the present study, NT3-mRNA was quantified in sympathetic effector tissues and NT3 protein was localized in intact and lesioned sympathetic nerves in rats. NT3-mRNA is expressed and developmentally regulated in many effector tissues including mesenteric arteries, salivary gland, heart and kidney but hardly detectable in the superior cervical ganglia of adult animals. The majority of sympathetic neurones express immunoreactivity for TrkA and TrkC in both neonatal and adult rats. Sympathetic somata are normally immunoreactive for NT3, but the immunoreactivity is abolished by systemic administration of NT3 antibodies or axotomy of postganglionic neurones, suggesting an accumulation of NT3 from extraneuronal sources. Furthermore, the detection of NT3-immunoreactivity in the internal carotid nerve as early as 3 h following a compression and only on the distal side indicates endogenous NT3 is retrogradely transported by sympathetic neurones. These studies provide evidence indicating that NT3, like nerve growth factor, is an effector tissue-derived neurotrophic factor for sympathetic neurones both during development and in the adult animal. Thus, we have provided a clear example that one type of neurone derives, through a retrograde transport mechanism, two neurotrophic factors simultaneously from its peripheral effector tissues. 相似文献
3.
Advances in genetic engineering and expression systems have led to a rapid progress in the development of immunoglobulins fused to other proteins. These 'antibody fusion proteins' have novel properties and include antibodies fused to the cytokine interleukin-2. In the present review we describe strategies for construction of these antibody-interleukin-2 fusion proteins and discuss their in vitro and in vivo properties. Antibody-interleukin-2 fusion proteins retain both antibody associated functions such as antigen binding, complement activation and Fc gamma receptor binding as well as interleukin-2 associated functions such as the stimulation of proliferation of CTLL2 cells. In vivo, they produce strong potentiation of the host immune response against any associated antigen. In addition, these novel molecules are able to target tumor cells and produce a specific and effective T cell response capable of eliminating the tumor. These properties suggest that antibody-interleukin-2 fusion proteins will be useful in the diagnosis and/or treatment of human cancer as well as in the potentiation of human response against any associated antigen. 相似文献
4.
S Aeschimann PA Kopp ET Kimura J Zbaeren A Tobler MF Fey H Studer 《Canadian Metallurgical Quarterly》1993,77(3):846-851
Thirty-nine thyroid nodules, removed because of recent growth, were analyzed morphologically by serial histological sections for the classical histomorphological hallmarks of follicular cell replication and for immunohistochemically demonstrable overexpression of the growth-associated ras-gene product p21ras. Clonal analysis was performed using the highly informative probe M27 beta that detects polymorphisms on the locus DXS255 of the X-chromosome. Twenty-four nodules were of clonal and 15 nodules were of poly-clonal origin. Only 3 out of the 24 clonal nodules were histomorphologically uniform. In all others, the structural hallmarks of active growth and the P21ras growth-marker expression were remarkably heterogeneous throughout the tumors. There were no histomorphological characteristics distinguishing these clonal tumors from polyclonal nodules. Even if a clonal thyroid tumor may be originally homogeneous in respect to the parameters studied here, mechanisms must exist that create wide heterogeneity of growth and of morphogenetic potential among the individual follicular cells during further expansion of the nodule. Thus, clonal nodules are much more common in nodular goiters than hitherto assumed on grounds of the classical morphological criteria. The diagnosis of a true monoclonal nodule can no longer rely on morphological and functional criteria alone but requires molecular or cytogenetic analysis of clonality. 相似文献
5.
Cyclosporine was introduced in 1981 as an immunosuppressive agent in renal transplantation. Its use was soon extended to the treatment of various glomerular disorders. In light of its known immunomodulating effects, the use of cyclosporine has been most prominent in those glomerular diseases thought to have an immune basis. The most careful studies of cyclosporine in glomerular diseases have been performed in the pediatric population with idiopathic nephrotic syndrome (i.e., minimal change disease and focal segmental glomerulosclerosis), although data are accumulating regarding efficacy and safety in adults with idiopathic nephrotic syndrome. In patients who are steroid-dependent, cyclosporine therapy can induce complete or partial remission in a significant proportion of cases; success rates in patients with steroid-resistant nephrotic syndrome are less encouraging. Treatment with cyclosporine allows for dose reduction or elimination of corticosteroids, and the consequent salutary effect on growth in the child and glucose and bone metabolism in all patients. Studies that suggest a potential benefit of cyclosporine in recurrent nephrotic syndrome in renal allografts and in other glomerular diseases are also discussed. 相似文献
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OBJECTIVES: A randomized trial was conducted to evaluate the effectiveness of a work-site health promotion program in reducing obesity and the prevalence of cigarette smoking. METHODS: Thirty-two work sites were randomized to treatment or no treatment for 2 years. Treatment consisted of health education classes combined with a payroll-based incentive system. Evaluation was based on cohort and cross-sectional surveys. RESULTS: Of 10,000 total employees in treatment work sites, 2041 and 270 participated in weight control and smoking cessation programs, respectively. Weight losses averaged 4.8 lbs, and 43% of smoking participants quit. Net 2-year reductions in smoking prevalence in treatment vs control work sites were 4.0% and 2.1% in cross-sectional and cohort surveys, respectively. No treatment effect was found for weight. Treatment effects for smoking prevalence and weight were both positively correlated with participation rates in the intervention programs (r = .45 for smoking and r = .55 for weight). CONCLUSIONS: This work-site health promotion program was effective in reducing smoking prevalence at a cost that is believed to make the investment worthwhile. 相似文献
9.
Activation of auditory cortex during silent lipreading 总被引:1,自引:0,他引:1
GA Calvert ET Bullmore MJ Brammer R Campbell SC Williams PK McGuire PW Woodruff SD Iversen AS David 《Canadian Metallurgical Quarterly》1997,276(5312):593-596
Watching a speaker's lips during face-to-face conversation (lipreading) markedly improves speech perception, particularly in noisy conditions. With functional magnetic resonance imaging it was found that these linguistic visual cues are sufficient to activate auditory cortex in normal hearing individuals in the absence of auditory speech sounds. Two further experiments suggest that these auditory cortical areas are not engaged when an individual is viewing nonlinguistic facial movements but appear to be activated by silent meaningless speechlike movements (pseudospeech). This supports psycholinguistic evidence that seen speech influences the perception of heard speech at a prelexical stage. 相似文献
10.
BF Waller ET Fry TF Peters JB Hermiller CM Orr J VanTassel CA Pinkerton 《Canadian Metallurgical Quarterly》1996,19(11):857-868
While abundant clinical and angiographic data are available regarding features of acute or abrupt closure at the site of balloon angioplasty, little morphologic information is available. This study discusses morphologic-histologic causes for acute closure after angioplasty in 130 necropsy patients. Intimal-medial flaps, elastic recoil, and primary thrombosis were the three leading morphologic causes for closure. Data were subdivided into time categories: abrupt (< 1 day), acute (< 1 week), and early (< 1 month). Intimal-medial flaps remained the most common cause for angioplasty closure despite time from angioplasty to documented occlusion. Morphologic recognition of types and frequencies of angioplasty closure are discussed, and specific mechanical, pharmacologic, or combined treatments are reviewed. 相似文献