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71.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、…  相似文献   
72.
青翘和老翘中连翘苷的含量测定   总被引:10,自引:0,他引:10  
目的:测定青翘与老翘中连翘苷含量。方法:。双波和薄层扫描法。结果:表翘中连翘苷含量为0.076%;老翘中仅占0.012%,与报道的青翘中连翘酯苷含量高于老翘的实验结果相同,结论;本文结果与文献报道的就抗菌效价而言青翘优于老翘的结论吻合,目前市售药材青老翘混杂,有必要进行深入研究,确定合理的采收期。  相似文献   
73.
Neutrophils isolated from cancer patients treated with granulocyte colony-stimulating factor (G-CSF) express high levels of Fc gamma RI. They exhibited an efficient killing of GD2+ neuroblastoma cells in the presence of an antidisialoganglioside (GD2) mouse monoclonal antibody (MoAb; 7A4, IgG3 kappa). However, this cytotoxicity was totally blocked by human monomeric IgG. In contrast, a bispecific antibody (7A4 bis 22/MDX-260), prepared by chemically linking an F(ab') fragment of 7A4 with an F(ab') fragment of an anti-Fc gamma RI MoAb, 22, which binds outside the Fc binding domain, triggered antibody-dependent cell cytotoxicity, even when neutrophils were preincubated with human monomeric IgG. F(ab')2 22 MoAb abrogated the MDX-260 killing without affecting that of 7A4. The 3G8 MoAb, directed against the Fc gamma RIII binding site, did not inhibit the cytotoxicity induced by either antibody. Thus, these results indicate that G-CSF-activated neutrophils exert their cytotoxic effect against neuroblastoma cells through Fc gamma RI and not Fc gamma RIII, and that the saturation of the high affinity Fc gamma RI by monomeric IgG can be overcome by the use of bispecific antibodies binding epitopes outside the IgG Fc gamma RI binding site. A combined administration of such bispecific antibodies and G-CSF may be, therefore, an efficient therapeutic approach to trigger tumor lysis by cytotoxic neutrophils in vivo.  相似文献   
74.
Clapp  DW; Freie  B; Lee  WH; Zhang  YY 《Blood》1995,86(6):2113-2122
We exploited the ability to transduce fetal liver hematopoietic stem/progenitor cells in situ with recombinant retrovirus, together with the ability to analyze proviral integration patterns into chromosomal DNA, to detect the cellular and organ fate of hematopoietic stem and progenitor-derived progeny in tissues and in the circulation of neonatal and adult rats. Two hundred seventeen fetuses were injected with retrovirus supernatant on day 16 of gestation, before the development of the bone marrow cavity. The progeny of 41 stem and progenitor cells from 97 liveborn rats were clonally identified. Pluripotent and lineage-restricted stem/progenitor clones derived from the fetal liver consistently gave rise to progeny in the marrow of newborn and adult rats. Patterns of differentiation of transduced stem and progenitor cells fell into distinct subsets. Blood cells derived from in situ transduced cells that originated in the fetal liver circulated throughout the life span of the adult animals. These data provide molecular evidence of the origin of medullary cavity hematopoiesis by cells derived from the fetal liver that were transduced in vivo, homed to the developing medullary cavity and proliferated in a normal medullary hematopoietic microenvironment.  相似文献   
75.
Two adults with bizarre parosteal osteochondromatous proliferation of the hands and feet are presented. The pre-operative diagnosis may be difficult to make and the correct diagnosis was not made in either case until pathological examination of recurrent tumour masses occurred. The radiological and pathological features of this lesion are discussed. The diagnostic features which differentiate this condition from other causes of new bone formation in the peripheries are described.  相似文献   
76.
Increased colonic wall thickness has been reported in patients exposed to large doses of high strength pancreatic enzyme preparations who did not develop fibrosing colonopathy. This has been interpreted as evidence for a spectrum of subclinical disease. The relation between sonographically measured colonic wall thickness and pancreatic enzyme preparation and dose was studied in 86 children with cystic fibrosis (CF). Colonic wall thickness of a control group was also measured. The average thickness in all colonic regions was higher in the CF group (overall average range 0.7-2.5 mm v 0.6-1.4 mm in the control group). There was no significant relation between colonic wall thickness and age, sex, total dose of lipase, or copolymer. Apart from one patient with an early colonic stricture, none of those exposed to high doses of lipase, or the methacrylic acid copolymer Eudragit L30 D55, showed evidence of subclinical damage to the colon. The reproducibility of the sonographic measurements was poor.  相似文献   
77.
OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens.  相似文献   
78.
一氧化氮与亚硝基硫醇相互转化机制的研究   总被引:3,自引:1,他引:2  
目的:探讨一氧化氮(NO)与亚胡基硫醇间的相互转化机制。方法:应用光谱扫描、毛细管电泳和化学发光等分析技术对NO和亚砂基硫醇(R-SNO)间的相互关系进行系统研究。结果:NO在含氧实验体系极不稳定,迅速被氧化为来硝酸盐,并进而在微酸性条下与还原性巯基结合为R-SNO。R-SNO可自发而缓慢的持续释放NO,且此释放速率由于自由基的存在而加速。结论:进一步从理化性质上为内皮细胞衍生舒血管因子是亚硝基复  相似文献   
79.
80.
In a distinct autosomal recessive variant of epidermolysis bullosa, EB- MD, life-long skin blistering is associated with late-onset muscular dystrophy of unknown etiology. Electron microscopy of these patients' skin suggests that tissue separation occurs intracellularly at the level of the hemidesmosomal inner plaque, which contains plectin, a high molecular weight cytoskeletal associated protein, also expressed in the sarcolemma of the muscle. In this study, we report two patients with EB-MD, each with a homozygous deletion mutation in the plectin gene, PLEC1. In the first case, the proband and her similarly affected sister had a homozygous 9 bp deletion mutation, designated as 2719de19, which resulted in elimination of three amino acids, QEA, in a sequence of 23 amino acids entirely conserved between the mouse and human sequences. The proband in the second family demonstrated a single nucleotide deletion at position 5866, designated as 5866delC, which resulted in frameshift and a premature termination codon for translation 16 bp downstream from the site of deletion. The absence of plectin in the hemidesmosomes, as reflected by negative immunofluorescence with an anti-plectin antibody (HD-1), associated with fragility of basal keratinocytes, implicates plectin as critical for binding of intermediate keratin filament network to hemidesmosomal complexes. The function of plectin as a putative attachment protein also in the muscle would explain the clinical phenotype consisting of cutaneous fragility and muscular dystrophy in EB-MD.   相似文献   
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