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41.
42.
大肠癌免疫组化表达与临床病理的关系   总被引:1,自引:0,他引:1  
目的:探讨大肠癌CEA、P53、nm23、Ki-67、MRP免疫组化表达特点和相互关系,及其与临床病理的关系.方法:回顾性分析2003-01/2006-07我院收治的73例大肠癌患者的临床病理及随访资料,并对其石蜡标本采用免疫组化SP染色法检测CEA、P53、nm23、Ki-67、MRP,分析其免疫组化特点及其与临床病理之间的关系.结果:CEA、P53、nm23、Ki-67、MRP在大肠癌中的阳性表达率依次为82.2%、68.5%、75.3%、84.9%和64.4%.CEA、MRP与大肠癌患者的各因素无统计学差异.P53、Ki-67和nm23与肿瘤的Dukes分期和淋巴结转移有关, P53、Ki-67在Dukes C、D期的阳性表达率(依次为82.8%和100%1明显高于Dukes A、B期者(59.1%和75.0%)(P<0.05),而nm23在Dukes C、D期的阳性表达率(58.6%)明显低于Dukes A、B期者(86.4%)(P<0.05).CEA与nm23的表达呈明显的负相关(r=-0.296,P=0.011),而P53和Ki-67表达之间呈现明显的正相关(r= 0.308,P=0.008),其他各指标间的表达无相关性.nm23、P53和Ki-67与预后因素关系明显,nm23在生存期≥3 a患者的阳性表达率(92.9%)高于生存期<3 a者(71.2%)(P<0.05),而P53和Ki-67在生存期≥3 a患者的阳性表达率(依次为42.9%和64.3%)明显低于生存期<3 a者(74.6%和89.8%)(P<0.05).结论:P53、Ki-67和nm23的表达与大肠癌的侵袭转移和预后密切相关.CEA可能是大肠癌的侵袭转移的促进因素.MRP所引起的耐药机制是一个相对独立的机制.CEA、P53、nm23、Ki-67可作为判断大肠癌恶性程度、侵袭转移以及预后的指标.  相似文献   
43.
Two hundred and sixteen patients with non-insulin-dependent diabetes (NIDDM) and 216 age- and gender-matched controls were studied to assess the prevalence of limited joint mobility (LJM). Joint mobility was measured by goniometry at metacarpophalangeal and subtalar joints, and those in whom a prayer sign was elicited were said to have cheiroarthropathy. Forty diabetic patients and 10 controls had cheirorathropathy. The mean range of motion was reduced at metacarpophalangeal joints in diabetic patients with cheiroarthropathy (36.8 +/- 9.2) and without cheiroarthropathy (45.7 +/- 8.1) when compared to controls (51.4 +/- 9, P < 0.01). Mobility at subtalar joints was reduced in those with cheiroarthropathy (25 +/- 5.3, P < 0.01) when compared to controls (32.4 +/- 4.1) and diabetic patients without cheiroarthropathy (27.4 +/- 4.6). No differences in subtalar mobility existed between diabetic patients without cheiroarthropathy and controls. Significant differences were observed in the presence of foot ulceration (35 vs 16%) in those with and without cheiroarthropathy. We conclude that cheiroarthropathy is seen in Sri Lankan patients with NIDDM and that significant limitation of joint mobility is present in patients with NIDDM who do not have overt cheiroarthropathy and that overt cheiroarthropathy may be a marker for a high risk of foot ulceration.   相似文献   
44.
Ravid  K; Kuter  DJ; Beeler  DL; Doi  T; Rosenberg  RD 《Blood》1993,81(11):2885-2890
A platelet factor 4 (PF4)-expressing cell line, HELNeo, was derived from the human erythroleukemia cell line, HEL. This was achieved by stable transfection of HEL cells with a construct containing the rat PF4 promoter driving the gene coding for resistance to neomycin, followed by selection of neomycin-resistant clones. HELNeo cells were all nonadhering and about 5% of the cells had polyploid nuclei (> or = 8N), as compared with 1% in HEL cells. Immunohistochemistry showed that about 90% of the HELNeo cells contained PF4, whereas only approximately 5% of the HEL cells contained PF4. No significant parallel enrichment was observed for other megakaryocytic markers, such as the glycoprotein complex IIb/IIIa, von Willebrand factor, and platelet activation- dependent granule to external membrane glycoprotein (PADGEM), which were present to a similar extent in both HEL and HELNeo lines. The increased expression of PF4 in HELNeo cells was confirmed by transient expression assays and was associated with a fivefold increase in trans- acting factors binding to the PF4 promoter. These cells should be a rich source for purifying trans-acting factors binding to the PF4 gene. Moreover, our study shows how a lineage-specific promoter may be used to generate lineage-specific cell lines from a multilineage hematopoietic cell line.  相似文献   
45.
Thein  SL; Hesketh  C; Brown  JM; Anstey  AV; Weatherall  DJ 《Blood》1989,73(4):924-930
Two families, one of Anglo-Saxon-Dutch descent, and the other, West Indian black, have an atypical beta thalassemia characterized by an unusually high level of Hb A2 in the heterozygous state. Restriction endonuclease mapping showed a deletion of about 1.35 kilobase (kb) in the 5' region of the beta globin gene. Direct sequencing of a specific region of genomic DNA amplified by a new modification of the polymerase chain reaction defined the deletion to be 1,393 base pairs (bp) and to be the same in both families. The deletion extends from 485 bp 5' to the mRNA CAP site to the middle of the second intervening sequence. This deletion, together with three others previously described that remove the 5' end of the beta gene but leave the delta gene intact, are all associated with unusually high levels of Hb A2 in the heterozygous state.  相似文献   
46.
Warren  AP; Patel  K; McConkey  DJ; Palacios  R 《Blood》1996,87(9):3676-3687
In our search for cell surface markers expressed on hematopoietic stem cells and/or very early progenitor cells we found that the Joro 177 monoclonal antibody (MoAb) bound to most hematopoietic cells in day 8/8.5 yolk sac, day 12 fetal liver, and day 13 fetal thymocytes; it stained hematopoietic stem cells and less immature lymphoid, myeloid, and erythroid-lineage cells, but not most thymocytes and splenic lymphocytes in adult mice. Joro 177 MoAb stimulated tyrosine phosphorylation of an integral of 124-kD protein and induced homotypic aggregation of lymphoid progenitor cells. Importantly, Joro 177 MoAb inhibited cell survival/growth and consequently the generation of lymphoid, myeloid, and erythroid lineage cells in vitro from early Lin- hematopoietic precursors. Joro 177 MoAb induced apoptosis of hematopoietic progenitor cells. Molecular cloning and expression indicated that Joro 177 MoAb recognizes a type II transmembrane protein, which is the mouse homologue of the human CD98 heavy chain gene. We suggest that CD98 is a cell membrane receptor involved in the control of cell survival/death of hematopoietic cells.  相似文献   
47.
The aim of this paper was to perform a systematic review of the pathogenesis of medication‐induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α‐and β‐adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.  相似文献   
48.
Twenty-five children aged 2-14 years (mean age 8.39 +/- 0.78 years) were studied prospectively during the first year after the diagnosis of type 1 diabetes. Of their clinical and metabolic features at diagnosis, only age showed a significant independent relationship with endogenous C-peptide production during the first year. Age was correlated with higher values for basal and stimulated plasma C-peptide at 7-14 days after diagnosis, at 6 months and at 12 months. At diagnosis, age was also associated with a higher value for HbA1c and a lower prevalence of insulin antibodies. C-peptide production peaked at 3 months and thereafter declined. Mean HbA1c and insulin requirement were both minimal at 6 months. At diagnosis, there were significant inverse relationships between basal C-peptide production and both insulin dose and HbA1c and between stimulated C-peptide production and HbA1c. Basal and stimulated C-peptide production were inversely related to insulin dose at 6 and 12 months. Stimulated C-peptide was higher at 12 months in children retaining islet cell antibodies. These findings confirm the importance of age as a predictor of residual beta-cell function in type 1 diabetes and indicate that older children present clinically following a slower course of beta cell destruction.  相似文献   
49.
Data on the distribution of beta thalassemia among over 6,000 Melanesians reveals a major difference in the carrier rates between populations in the malarious coastal regions of New Guinea and those living in the historically malaria-free Highlands. The island of Maewo in Vanuatu has a particularly high incidence of beta + thalassemia associated with a single restriction enzyme haplotype. Direct cloning into a plasmid vector and sequence analysis demonstrate that the mutation is a G to C transversion at position 5 of intron 1 of the beta- globin gene. Oligonucleotide probe surveys indicate that this variant accounted for all cases of beta thalassemia studied from Maewo. It is also common in coastal Papua New Guinea where haplotype and oligonucleotide probe data suggest that the molecular basis of beta thalassmia is more heterogeneous.  相似文献   
50.
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