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81.
背景:在亚洲、非洲和欧洲,致病性H5N1流感病毒引起禽流感在家禽和候鸟中爆发流行,还导致了人类发病和死亡。虽然目前H5N1毒株引起人与人之间的传染不太可能,但它仍可能是未来流感大范围流行的潜在威胁因素。本试验的目的就是评价针对H5N1病毒株的裂解病毒疫苗的安全性和免疫原性。方法:对300名志愿者(年龄为18岁~40岁)进行随机、开放标签的、无对照的Ⅰ期试验。300名志愿者被分为6组:7.5mg血凝素加佐剂组(n=50)、7.5mg血凝素不加佐剂组(n=49)、15mg血凝素加佐剂组(n=50)、15mg血凝素不加佐剂组(n=50)、30mg血凝素加佐剂组(n=51)、30mg血… 相似文献
82.
Jaap Huisman Eline J Aukema Jan Berend Deijen Silvia CCM van Coeverden Gertjan JL Kaspers Heleen JH van der Pal Henriette A Delemarre-van de Waal 《BMC pediatrics》2008,8(1):25
Background
To reduce the risk of brain damage children with acute lymphoblastic leukaemia (ALL) are nowadays mainly treated with intrathecal chemotherapy (ITC) instead of central nervous system (CNS) radiation therapy (CRT) to prevent CNS relapse. However, chemotherapy may also lead to cognitive deficits. As growth hormone deficiency (GHD) or impaired growth hormone secretion are frequently found in ALL patients treated with cranial radiation therapy and/or chemotherapy, we hypothesized that GH therapy may reduce cognitive deficits in these patients. 相似文献83.
Benzo[a]pyrene at an environmentally relevant dose is slowly absorbed by, and extensively metabolized in, tracheal epithelium 总被引:2,自引:0,他引:2
Gerde P; Muggenburg BA; Thornton-Manning JR; Lewis JL; Pyon KH; Dahl AR 《Carcinogenesis》1997,18(9):1825-1832
While tobacco smoke has been conclusively identified as a lung carcinogen,
there is much debate over which smoke constituent(s) are primarily
responsible for its carcinogenicity. Previous studies in our laboratory
suggested that highly lipophilic carcinogens are slowly absorbed in the
thicker epithelium of the conducting airways, potentially allowing for
substantial local metabolism. The bioactivation of polycyclic aromatic
hydrocarbons in airway epithelium may, hence, be important in tobacco
smoke-induced carcinogenesis. In the present study, the hypothesis of slow
absorption and substantial local metabolic activation of highly lipophilic
carcinogen in airway epithelium was tested in dogs. A single dose of
tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid
suspension was instilled in the trachea, just anterior to the carina. At
intervals of a few minutes up to 30 min over a 3-h period, blood samples
were drawn from the azygous vein, which drains the area around the point of
instillation, and from the systemic circulation. Tissue samples were taken
at the end of the experiment. The concentration of BaP with depth into the
tracheal mucosa was determined with autoradiography. BaP was slowly
absorbed into the trachea with a half-time of approximately 73 min, which
is consistent with diffusion-limited passage through the epithelium and
lead to local doses in the tracheal epithelium that were more than a
1000-fold those of other tissues. The long retention of BaP in the
epithelium provided the local metabolizing enzymes with high substrate
levels over a long period, resulting in extensive metabolism. At 3 h after
the exposure, 23% of the BaP-equivalent activity remained in the tracheal
mucosa. Of this fraction, 13% was parent compound, 28% was organic
extractable, 31% was water-soluble, and 28-7% of the instilled dose was
bound to tracheal tissues. These results explain the tendency of highly
lipophilic carcinogens, such as BaP, to induce tumors at the site of entry
and, furthermore, indicate that the highly lipophilic components of tobacco
smoke and polluted air may be the most important contributors to lung
tumors of the conducting airways.
相似文献
84.
S. E. Parkes K. R. Muir A. H. Cameron F. Raafat M. C. Stevens B. J. Morland P. C. Barber M. P. Carey H. Fox E. L. Jones H. B. Marsden J. R. Pincott J. A. Pringle H. Reid D. I. Rushton C. M. Starkie H. L. Whitwell D. H. Wright J. R. Mann 《British journal of cancer》1997,75(8):1156-1159
A retrospective histopathological review of 2104 cases of solid tumour was carried out to assess the variability in diagnosis of childhood cancer. Cases were subject to three independent, concurrent opinions from a national panel of specialist pathologists. The conformity between them was analysed using the percentage of agreement and the kappa statistic (kappa), a measure of the level of agreement beyond that which could occur by chance alone, and weighted kappa (w kappa), which demonstrates the degree of variation between opinions. The major groupings of the Birch-Marsden classification were used within which tumours were assigned for kappa analysis according to the clinical significance of the differential diagnoses. The mean agreement for all tumours together was 90%; kappa = 0.82, w kappa = 0.82. Retinoblastoma achieved the highest kappa value (1.0) and lymphoma the lowest (0.66). Of the cases, 16.5% had their original diagnoses amended and the panel confirmed the original diagnosis of paediatric pathologists in 89% of cases compared with 78% for general pathologists. The varying levels of agreement between experts confirm the difficulty of diagnosis in some tumour types, suggesting justification for specialist review in most diagnoses. Specialist training in paediatric pathology is also recommended. 相似文献
85.
JL Emery 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S394):40-46
It is an honour to have been asked to contribute to this volume that commemorates the life and work of Spyros Doxiadis. Spyros was, and is still, a vital and stimulating influence on those of us who were fortunate enough to have been his colleague in all phases of his life. My period of closeness to him was when he was working in Sheffield with Ronald Illingworth. At that time (now over 40 years ago) he and Katherine were having their children and my wife and I was having ours. Then words like "bonding" had not become commonplace as today, but the functional patterns of family relationships were something about which we were intensely aware. I particularly remember a summer when we were holidaying on a tidal estuary between Anglesey and Holy Island and recall a moment when Spyros and I were sitting on a grass topped sandbank watching our children and wives at the water's edge "messing around" with a boat. We watched and discussed the beauty of the postures and poses of our womenfolk with the children and the children with each other. It was the memory of that conversation that stimulated me to propose the topic of this essay in Spyros' memory. 相似文献
86.
Effects of growth hormone therapy in prepubertal children with short stature secondary to intrauterine growth retardation 总被引:1,自引:0,他引:1
A total of 130 short children were included in a French multicentre study and randomized between a control group (group A) and two groups treated with daily subcutaneous injections of GH at doses of 0.7 IU/kg/week (group B) and 1.4 IU/kg/week (group C) for 2 years. Height velocity was significantly increased ( p <0.0005) in groups B and C, with a greater increase in group C than in group B ( p < 0.001). The benefit after 2 years compared with controls was 4.3 cm in group B and 5.9 cm in group C. The rate of bone maturation was not affected by GH therapy. These results led to the conclusion that 2 years of treatment with GH improves final height prognosis in children with short stature secondary to IUGR, and that this effect is dose dependent. The effect on final height has still to be demonstrated. 相似文献
87.
Colorectal hemangioma: radiologic findings 总被引:1,自引:0,他引:1
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma. 相似文献
89.
8名男性健康志愿者po阿米替林100 mg后,以阿米替林及其3种代谢物的血浓度曲线下面积(AUC0∞)计算阿米替林的脱甲基化代谢及羟基化代谢能力。结果提示个体间阿米替林及其3种代谢物的AUC差异很大。其中7名志愿者测定异喹呱羟化代谢表型,6例为异喹呱强代谢者,1例为弱代谢者。尿中异喹呱的羟化代谢率与阿米替林的羟基化代谢率、阿米替林和10-羟基阿米替林的AUC0∞呈显著相关。阿米替林总血浆清除率与异喹呱羟化代谢率呈弱相关。此结果表明阿米替林和异喹呱的羟化代谢可能由同一酶控制,阿米替林的羟基化代谢和脱甲基化代谢可能为两个独立的代谢途径。 相似文献
90.
In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed. 相似文献