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101.
102.
Metastatic prostatic carcinoma presenting as left-sided cervical lymphadenopathy: a series of 11 cases 总被引:2,自引:0,他引:2
Eleven cases of metastatic prostatic carcinoma in cervical lymph nodes as a primary presenting sign were identified in a survey of 250 cervical lymph node biopsies from men. The diagnosis was clinically unsuspected in all cases. All occurred on the left side of the neck. These 11 cases represented 11% of all metastatic carcinomas in the neck and 20% of those with left-sided involvement. The diagnosis was readily confirmed by immunostaining for prostate specific antigen and prostate specific acid phosphatase. Six patients are alive and well at an average of 25.8 months and five others survived for an average of 34.4 months, the combined survival being 29.7 months. This contrasts with the dismal fate of patients with metastatic adenocarcinoma from other sites who all died at an average of 2 months from diagnosis. Prostatic carcinoma should always be considered in the differential diagnosis of metastatic carcinoma in cervical lymph nodes in elderly men, as appropriate treatment results in worthwhile prolongation of life. 相似文献
103.
Ji-Su Li Shu-Ping Tong Ludmila Vitvitski Christian Trpo 《Journal of medical virology》1995,45(2):151-155
Hepatitis C virus (HCV) exhibits considerable sequence variability and circulates in the blood at extremely low levels. Current methods for detecting HCV RNA are based mostly on nested polymerase chain reaction (PCR), in which part of the first amplification product is reamplified in the second tube by an internal primer pair. A novel nested PCR method was developed in which the two successive amplification processes are carried out in the same tube with a single step of physical manipulation. Careful selection of highly conserved sequences of the 5′ noncoding region as primers enabled successful detection of all three major genotypes circulating in France, including the one with variation in this region. Retaining high sensitivity of the conventional nested PCR, the novel method reduced greatly the risk of carry-over contaminations. It was also cost- and time-saving. The one-step nested PCR method is especially suitable for routine diagnosis of HCV infection in clinical laboratories. © 1995 Wiley-Liss, Inc. 相似文献
104.
Immunohistochemical study of neuron specific enolase and S-100 protein in Hirschsprung's disease 总被引:3,自引:0,他引:3
Tomoaki Taguchi Kenzo Tanaka Keiichi Ikeda 《Virchows Archiv : an international journal of pathology》1985,405(4):399-409
Summary The distribution of whole differentiated neurons in the intestines from 15 children with Hirschsprung's disease was investigated using neuron specific enolase (NSE) and the perineuronal elements were studied using S-100 protein immunostaining.In aganglionic segments, NSE immunoreactive ganglion cells and S-100 positive satellite cells were absent, but the hypertrophic nerve trunks did show a markedly positive NSE and S-100 immunoreactivity.Two different forms of aganglionic segment were present. One was the middle aganglionic segment of long segment aganglionosis which was almost completely dennervated. In the other type, there were several NSE positive nerve fibers in the muscularis propria of both the aganglionic segment of short segment aganglionosis and the distal aganglionic segment of long segment aganglionosis. These latter two aganglionic segments seemed to be innervated by extrinsic nerves. 相似文献
105.
Appearance of extrachromosomal circular DNAs during in vivo and in vitro ageing of mammalian cells 总被引:4,自引:0,他引:4
T Kunisada H Yamagishi Z Ogita T Kirakawa Y Mitsui 《Mechanisms of ageing and development》1985,29(1):89-99
Appearance of extrachromosomal circular DNAs with in vivo and in vitro cellular ageing was examined by using a new technique of mica-press-adsorption for electron microscopy. The size distribution and the copy number of circular DNA complexes varied, depending on the cellular age. Extrachromosomal circular DNA complexes of variable length of more than 0.5 microns or 1.5 kilobase (kb) appeared during in vivo ageing of rat lymphocytes and in vitro ageing of cultured human lung fibroblasts. A restricted size class of circular forms of less than 0.5 microns in contour length was amplified in human skin fibroblasts from aged normal or Werner's syndrome subjects. These circular DNA molecules are suggested to be products of DNA rearrangements or gene amplification occurring in the chromosome. 相似文献
106.
Effects of Killed and Live Attenuated Influenza Vaccine on Symptoms and Specific Airway Conductance in Asthmatics and Healthy Subjects 总被引:1,自引:0,他引:1
Killed and live influenza virus vaccines were given to asthmatics and healthy subjects to investigate symptoms and alterations in their respiratory performance after vaccination. Polyvalent killed influenza virus vaccine was given to 16 asthmatics and live attenuated influenza virus vaccine to 23 asthmatics and 21 healthy subjects. Fourteen of the 16 asthmatics vaccinated with the killed vaccine displayed a significant rise in serum antibody level as measured by a single radial haemolysis in gel (SRH test). 11 of the 23 asthmatics and 14 of the 21 healthy subjects vaccinated with the live attenuated vaccine displayed a significant rise in the SRH test. Among the subjects with no measurable initial antibodies and with a significant rise in the SRH test, one asthmatic vaccinated with the killed vaccine experienced symptoms of common cold with fever and dyspnoea 1 week after vaccination. Three asthmatics and four healthy subjects vaccinated with live attenuated vaccine experienced mild symptoms, mainly rhinorrhoea, cough and sore throat 2 to 3 days after vaccination. No alterations in specific airway conductance in asthmatics or in healthy subjects were observed. We conclude that both killed and live attenuated influenza virus vaccines are tolerated well by asthmatics and appear to be safe for asthma patients. 相似文献
107.
108.
Detailed investigation of factors influencing amplification efficiency and allele drop-out in single cell PCR: implications for preimplantation genetic diagnosis 总被引:16,自引:0,他引:16
Preimplantation genetic diagnosis (PGD) of single gene disorders relies on PCR-based tests performed on single cells (polar bodies or blastomeres). Despite the use of increasingly robust protocols, allele drop-out (ADO; the failure to amplify one of the two alleles in a heterozygous cell) remains a significant problem for diagnosis using single cell PCR. In extreme cases ADO can affect >40% of amplifications and has already caused several PGD misdiagnoses. We suggest that an improved understanding of the origins of ADO will allow development of more reliable PCR assays. In this study we carefully varied reaction conditions in >3000 single cell amplifications, allowing factors influencing ADO rates to be identified. ADO was found to be affected by amplicon size, amount of DNA degradation, freezing and thawing, the PCR programme, and the number of cells simultaneously amplified. Factors found to have little or no affect on ADO were local DNA sequence, denaturing temperature (94 or 96 degrees C) and cell type. Consideration of the causal factors identified during this study should permit the design of PGD protocols that experience little ADO, thus improving the accuracy of PGD for single gene disorders. 相似文献
109.
胃肠道癌患者血清中抗癌胚抗原(CEA)抗体的检测及意义 总被引:1,自引:0,他引:1
目的:探讨循环中抗癌胚抗原(CEA)特异性抗体的情况,评价CEA及抗体的联合检测在胃肠道癌诊断中的作用。方法:用放免法检测血清中 CEA含量,用酶联免疫吸附法(ELISA)检测抗 CEA IgG抗体,用竞争抑制法检测抗体的特异性。结果:胃肠道癌患者血清 CEA含量升高者(≥15 ng/ml)为 30.9%(21/68),抗 CEA IgG抗体阳性者为35.3%(24/68),CFA及抗 CEA抗体的联合检测可使阳性率提高到54.3%(37/68);胃肠道良性疾病患者(多发性息肉、溃疡、胰腺炎等)血清CEA升高者为3.3%(1/30),抗 CEA IgG抗体阳性者为 3.3%(1/30);健康对照组血清 CEA升高者为 0,抗 CEA IgG抗体阳性者为 2.5%(1/40)。结论:胃肠道癌患者血清中抗癌胚抗原(CEA)抗体的检出率较高,这些抗体可作为胃肠道癌的一种肿瘤标志物。 相似文献
110.
Han Lü Sixun Zheng Bing Zhang Xiaozhen Tang 《Macromolecular chemistry and physics.》2004,205(6):834-842
Summary: The blends of poly(hydroxyether sulfone) (PHES) with poly(N‐vinylpyrrolidone) (PVPy) were investigated by means of differential scanning calorimetry (DSC) and FTIR spectroscopy. The miscibility of the blend system was established on the basis of the thermal analysis results. DSC showed that the PHES/PVPy blends prepared by casting from N,N‐dimethylformamide (DMF) possessed single, composition‐dependent glass transition temperatures, indicating that the blends are miscible in the entire composition. The experimental glass transition temperatures have higher values than those calculated on the basis of additive behavior; the variation of the glass transition temperatures of the blends was accounted for by the Kwei equation. FTIR studies indicate that competitive hydrogen bonding interactions exist upon addition of PVPy to the system, which were involved in the self‐ and cross‐association, i.e., ? OH···O?S, ? OH···OH of PHES and ? OH···O?C< of PVPy. The FTIR spectra in the range of the sulfonyl stretching vibrations showed that the hydroxyl‐associated sulfonyl groups are partially “set free” upon addition of PVPy to the system. The IR spectroscopic investigation of both the model compounds and the PHES/PVPy blends suggests that the strength of the hydrogen bonding interactions in the blend system increases in the following order: ? OH···O?S, ? OH···OH and ? OH···O?C<.