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51.
肺神经内分泌癌的免疫组化与免疫电镜研究   总被引:3,自引:1,他引:3  
本文应用免疫组化与免疫电镜技术对20例肺神经内分泌癌进行了研究,另6例非神经内分泌癌作为对照。结果表明:嗜铬颗粒蛋白A免疫组化染色19/20例阳性,免疫电镜能够比较特异地标记神经分泌颗粒,具有确诊意义;神经特异性烯醇化酶染色20/20例阳性,非神经内分泌癌3/6例阳性,免疫电镜下无特异性分布,适宜作为诊断的筛选指标;S-100蛋白和5-HT亦可作为诊断之参考。  相似文献   
52.
Inhibition of chemokines prevents intraperitoneal adhesions in mice   总被引:2,自引:0,他引:2  
BACKGROUND: The present study evaluates the efficacy of a broad-spectrumchemokine inhibitor, NR58-3.14.3, in the prevention of adhesionformation after i.p. surgery in mice. METHODS: A total of 110eight week old female Balb/c mice underwent laparotomy. Fortyanimals were randomly assigned to receive daily i.p. injectionsof either vehicle (control) or NR58-3.14.3. Time-course of adhesionformation was assessed. A titration of NR58-3.14.3 was conductedfor i.p. and s.c. administrations. The effectiveness of a singleintra-operative dose of NR58-3.14.3 was evaluated. Number, extent,location and type of adhesions were recorded. Immunohistochemistryof adhesions was done with leukocyte common antigen, CD45. RESULTS:Adhesion scores peaked on post-operative days 6–8. Onboth days 6 and 8, there were smaller adhesion size and lowercumulative adhesion scores in NR58-3.14.3-treated group. Moreover,on day 8, there were significantly fewer adhesions in NR58-3.14.3-treatedgroup compared to controls. The least effective dose for i.p.administration of NR58-3.14.3 was 0.45 mg/animal. Subcutaneousand single intra-operative i.p. administrations were also effectivein the prevention of i.p. adhesions. Although NR58-3.14.3 decreasedthe number of CD45+ inflammatory cells in the adhesions by 22.5%compared to control group, this was not significant. CONCLUSIONS:Our results show that this broad-spectrum chemokine inhibitorprevents post-operative adhesions in mice and may have a potentialclinical use.  相似文献   
53.
Vitamin K is the cofactor for the hepatic carboxylation of glutamic acid residues in a number of proteins including the procoagulants factors II, VII, IX, and X. The role of vitamin K in normal bone function is not fully understood. Inherited deficiency of vitamin K dependent coagulation factors is a rare bleeding disorder reported only in a few patients. Here we present an 18-month old child who presented with osteopeni due to inherited vitamin K deficiency. While the patient had high bone specific alkaline phosphatase and parathyroid hormone levels and low osteocalcin and bone mineral density values, with the regular supplementation of vitamin K all the mentioned parameters returned to normal values.  相似文献   
54.
55.
A potential molecular marker associated with cancer susceptibility as well as metastasis, prognosis and adverse survival, is the L-myc gene. The studies of lung cancer patients from different populations have yielded controversial results. We studied 64 nonsmall cell lung cancer (NSCLC) patients and 37 healthy controls of Turkish origin for L-myc gene polymorphism. Our aim was to test the hypothesis that there was association between L-myc S allele in NSCLC and predisposition to the disease and TNM stage indicating tumor size, node classification and metastasis. Polymerase chain reaction restriction fragment length polymorphism and agarose gel electrophoresis were used to determine the L-myc oncogene genotypes. We found no significant difference, both in the distribution of the LL, LS and SS genotypes and in the allelic frequencies, between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data concerning age, sex, size of tumors, histological type of tumors showed no significant association with L-myc genotype. However, a higher frequency of L-myc S allele in the squamous cell carcinoma compared to other histological groups was found, although this difference was not statistically significant. No association was found between the L-myc RFLP and increased risk of metastasis either to the lymph nodes or to other organs. Our results suggested that L-myc gene polymorphism was not a suitable prognostic marker of metastatic development in Turkish NSCLC patients.  相似文献   
56.
57.
Seventy-three clinical isolates of "Campylobacter upsaliensis" were screened for the presence of plasmids. Plasmid bands were found in 68 (93%) isolates, from which 14 plasmid types were identified. Type 5 was found only in blood-culture isolates, whereas types 7-14 were found only in faecal isolates. Plasmid-free isolates and the other plasmid profiles were present in both faecal and blood isolates. The reproducibility of these profiles was largely dependent on the method of plasmid isolation. The chloroform-phenol lysis method was the most efficient and reliable method of preparing plasmid DNA for plasmid profile analysis. The success of this method may be largely attributable to two factors: (1) the efficacy of cell lysis was independent of either an alkaline agent or of heat; (2) the inactivation of nucleases by the utilisation of chloroform-phenol to lyse the cells. Furthermore, this method of plasmid DNA preparation is ideally suited for use on clinical isolates, especially when rapid plasmid profile analysis may be required.  相似文献   
58.
The incidence of HL-A antigens in patients having a variety of medical conditions, but sharing the common feature of a positive antiglobulin test of the red cells, was determined. There was a significant increase in the antigens HL-A 1 and HL-A 8 and of the 1 and 8 combination when compared with a control group. It is suggested that the presence of these antigens may predispose to autoallergy.  相似文献   
59.
Heat shock protein 60 (HSP60) from Chlamydia pneumoniae was described to trigger in vitro inflammatory and cytokine responses including TNF and IL-12p40. Although it can be found in atherosclerotic plaques of patients, the stimulatory potential of chlamydial and other HSP60 in vivo is unclear. We now report that chlamydial HSP60 fails to induce TNF expression in vivo, and significant serum levels of IL-12p40 are only found upon intraperitoneal injection of high doses of HSP60 or after intravenous application. Upon purification of chlamydial HSP60 with polymyxin B-agarose columns, its ability to induce TNF secretion in vitro is much reduced. However, purified chlamydial HSP60 causes increased serum levels of the CXC chemokines KC and MIP2 in vivo, as well as a strong accumulation of polymorphonuclear neutrophils (PMN) in the peritoneal cavity upon intraperitoneal challenge. With respect to PMN accumulation, chlamydial HSP60 is more potent than endotoxin or the CpG oligonucleotide 1668. The responses observed are completely abolished in Toll-like receptor (TLR)2/4-double-deficient mice, while single-deficient mice respond almost normally. Furthermore, KC induction and PMN accumulation are largely dependent on MyD88. In conclusion, HSP60 from C. pneumoniae triggers inflammatory responses in vivo that differ from responses induced by endotoxin or CpG oligonucleotides and are dependent on TLR2 and 4.  相似文献   
60.
The patterns of exochorion ornaments on eggs of seven South American Lutzomyia sand fly species were analyzed by scanning electron microscopy (SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia) intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912), L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L. renei (Martins, Falcao, and Silva 1957). Different patterns were observed, which showed the distinction between some species. Egg ornaments in L. cruzi and L. longipalpis appear as single, parallel, unconnected ridges, whereas eggs of L. migonei appear as single, parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N.) neivai present a new variation of the single, unconnected, parallel ridges pattern: small tubercles are present, distributed between the ridges. Eggs of L. renei present an elliptical pattern, with most structures connected by straight ridges. Eggs of L. (M.) evandroi present a polygonal pattern, with alternate rows of small and large hexagons. Our data emphasize the advantages of the SEM approach in the study of the exochorion patterns of Lutzomyia eggs and in the distinction of the sand fly species.  相似文献   
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