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51.
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo.  相似文献   
52.
A 50-year-old Danish man, who neither had wasting disease nor was taking steroid-containing drugs, complained of abdominal distension, due to a markedly enlarged liver. Percutaneous needle biopsies were taken from the liver, and the findings gave suspicion of a neoplastic tumor. Because of reduced liver function and treatment-resistant ascites, he underwent liver transplantation without a definite preoperative diagnosis. The resected liver weighed 2900?g, and almost all of the parenchyma was destroyed and replaced by multicystic blood-filled spaces, diagnosed as extensive peliosis hepatis complicating liver cirrhosis. Extensive peliosis with liver cirrhosis is a rare condition. Only two cases, caused by contraceptives and treated by liver transplantation, are reported in the English-language literature. We could find no cause other than alcohol abuse lasting several years in this patient, and classified the present case as idiopathic extensive peliosis hepatis. Although scarce subjective findings and misleading liver biopsies made an exact diagnosis difficult, an orthotopic liver transplantation was the only treatment for such complicated peliosis hepatis.  相似文献   
53.
Gonococcal arthritis is typically acute and appears within 3 weeks after initial infection. Chronic gonococcal arthritis is now exceptionally rare, since the advent of the antibiotic era. Numerous host factors are involved in gonococcal dissemination, such as complement deficiency, HIV and gonococcus strain characteristics. Gonococcal arthritis shares the same risk factors. In this instance, our patient was a 16-year-old girl suffering from persistent polyarthralgia with joint swelling presenting with brief flare-ups for a period of 1 year. She disclosed a single episode of unprotected sexual intercourse 1 year ago, i.e. just before developing her first rheumatological symptoms. Therefore, we performed a joint aspiration (arthrocentesis), and synovial fluid was inoculated directly into aerobic and anaerobic blood culture bottles, which tested positive for Neisseria gonorrhoeae within 24 h. Clinical presentation was consistent with previous reports of chronic gonococcal arthritis. Further investigation revealed a C5 complement deficiency, which might explain the chronic Neisseria process. A favourable outcome was reached after a ten-day course of IV ceftriaxone, with no apparent sequelae found during follow-up 6 weeks later. This case demonstrates an unusual gonococcal arthritis with brief flare-ups for the course of a year, followed by a subacute form. N. meningitidis infections, similar to N. gonorrhoeae, are typically acute and may sometimes be involved in chronic processes. However, this characteristic appears to be rare in the case of N. gonorrhoeae. Risk factors for this chronic process will be discussed with a review of the literature.  相似文献   
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小鼠皮肤超氧化物歧化酶活性与枸杞多糖的干预   总被引:1,自引:0,他引:1  
目的:观察枸杞多糖对皮肤胶原代谢和自由基产生的影响,探讨其抗皮肤衰老的作用。方法:实验于2005-06/2006-05在广东医学院整形外科研究所完成。①实验材料:清洁级昆明小鼠60只,月龄2个月,体质量16~24g,雌雄各半。②实验分组:将小鼠随机分为正常对照组、衰老模型组和抗衰老模型组,每组20只。③实验干预:模型组每日用D-半乳糖溶液皮下注射制造衰老模型,用量和时间为80mg/(kg·d)7d,120mg/(kg·d)14d,140mg/(kg·d)14d,180mg/(kg·d)7d。正常对照组每日注射同体积的生理盐水。抗衰老模型组在注射D-半乳糖期间以枸杞多糖灌胃,剂量为20mg/(kg·d),正常对照组和衰老组则以同体积的生理盐水代之灌胃。④实验评估:42d后切取小鼠颈背部皮肤,测定超氧化物歧化酶活力、羟脯氨酸和丙二醛含量。结果:56只小鼠进入结果分析(4只死亡)。①小鼠皮肤超氧化物歧化酶活力:与正常对照组相比,衰老组和抗衰老组小鼠皮肤超氧化物歧化酶活力降低,差异有显著性意义(P<0.01);抗衰老组与衰老模型组比较,超氧化物歧化酶活力增加,差异有显著性意义(P<0.01)。②与正常对照组相比,衰老组和抗衰老组小鼠皮肤羟脯氨酸和丙二醛含量增加,差异有显著性意义(P<0.01);抗衰老组与衰老组比较,羟脯氨酸和丙二醛含量均降低,差异有显著性意义(P<0.01)。结论:枸杞多糖改善皮肤老化的作用与提高小鼠皮肤超氧化物歧化酶活力,降低羟脯氨酸、丙二醛含量,影响胶原代谢有关。  相似文献   
56.
Szilvassy  SJ; Cory  S 《Blood》1994,84(1):74-83
Efficient gene delivery to multipotential hematopoietic stem cells would greatly facilitate the development of effective gene therapy for certain hematopoietic disorders. We have recently described a rapid multiparameter sorting procedure for significantly enriching stem cells with competitive long-term lymphomyeloid repopulating ability (CRU) from 5-fluorouracil (5-FU)-treated mouse bone marrow. The sorted cells have now been tested as targets for retrovirus-mediated delivery of a marker gene, NeoR. They were cocultured for 4 days with fibroblasts producing a high titer of retrovirus in medium containing combinations of the hematopoietic growth factors interleukin-3 (IL-3), IL-6, c-kit ligand (KL), and leukemia inhibitory factor (LIF) and then injected into lethally irradiated recipients, together with sufficient "compromised" bone marrow cells to provide short-term support. Over 80% of the transplanted mice displayed high levels (> or = 20%) of donor- derived leukocytes when analyzed 4 to 6 months later. Proviral DNA was detected in 87% of these animals and, in half of them, the majority of the hematopoietic cells were marked. Thus, infection of the stem cells was most effective. The tissue and cellular distribution of greater than 100 unique clones in 55 mice showed that most sorted stem cells had lymphoid as well as myeloid repopulating potential. Secondary transplantation provided strong evidence for infection of very primitive stem cells because, in several instances, different secondary recipients displayed in their marrow, spleen, thymus and day 14 spleen colony-forming cells the same proviral integration pattern as the primary recipient. Neither primary engraftment nor marking efficiency varied for stem cells cultured in IL-3 + IL-6, IL-3 + IL-6 + KL, IL-3 + IL-6 + LIF, or all four factors, but those cultured in IL-3 + IL-6 + LIF appeared to have lower secondary engraftment potential. Provirus expression was detected in 72% of the strongly marked mice, albeit often at low levels. Highly efficient retroviral marking of purified lymphomyeloid repopulating stem cells should enhance studies of stem cell biology and facilitate analysis of genes controlling hematopoietic differentiation and transformation.  相似文献   
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INTRODUCTION:

In France, young adults are legally freed from parental authority at the age of 18 years and are, thus, responsible for their own vaccine record. This young adult population is more frequently exposed to vaccine-preventable infectious diseases.

OBJECTIVE:

To determine the factors associated with students’ knowledge of the interval between two antitetanus boosters and their report of having up-to-date vaccinations.

METHODS:

In April 2009, a survey was conducted involving a random sample of students between 18 and 25 years of age eating lunch at university dining facilities in Paris and its suburbs (Ile de France).

RESULTS:

Among the 677 students approached, 583 agreed to participate. Only 207 (36%) of respondents knew the recommended dosing interval between two doses of tetanus vaccine booster (10 years). The majority of students (69%) reported having up-to-date vaccinations. Declaring having up-to-date vaccinations was significantly associated with having a general practitioner (OR 3.03 [95% CI 1.69 to 5.55]). Health care students were significantly more likely to know the decennial interval between two antitetanus boosters (OR 2 [95% CI 1.28 to 3.25]). Most of responding students (n=519 [89%]) believed that vaccines were very useful.

CONCLUSIONS:

An overall lack of knowledge of vaccines was observed among this student population. Health care providers, such as GPs and university medical practice staff, who interact with these young individuals have an essential role to promote better vaccination coverage in this population.  相似文献   
60.
This is the first controlled study of the frequency of backpain in a European caucasian population with diffuse idiopathicskeletal hyperostosis (DISH). Elderly patients admitted to hospital for reasons other thanback pain were assessed for the presence of spinal DISH usingthe routine lateral chest radiograph films. A total of 106 probands(82 males, 24 females) with a mean age of 70 years fulfilledthe criteria for DISH as defined previously. One hundred andseventyeight patients (117 males, 61 females) not meeting thesecriteria were used as controls. The prevalence of back painwas assessed by a blinded interviewer using a structured questionnaire.Our primary hymthesis was that spinal DISH positive probandshad not had back pain more often than controls. The controlledstudy showed no statistically significant difference in painfrequency between spinal DISH positive probands and controlsat any spinal level. We conclude that back pain does not occur more often in radiographicallydefined DISH positive probands than in controls. The radiologicalfinding of spinal DISH, as far as it does not lead to stenosisof the spinal canal or dysphagia, thus seems to be a findingwithout clinical relevance. KEY WORDS: Spine, Radiographs, Pain, Osteoarthritis, Forestier's disease, Ankylosing vertebral hyperostosis  相似文献   
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