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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
4.
Germline mutations of the CDKN2 gene in UK melanoma families 总被引:4,自引:1,他引:4
Harland M; Meloni R; Gruis N; Pinney E; Brookes S; Spurr NK; Frischauf AM; Bataille V; Peters G; Cuzick J; Selby P; Bishop DT; Bishop JN 《Human molecular genetics》1997,6(12):2061-2067
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin
D kinase inhibitor p16, and more rarely, mutations in the gene coding for
CDK4, the protein to which p16 binds, underlie susceptibility in some
melanoma families. We have sequenced all exons of CDKN2 and analysed the
CDK4 gene for mutations in 27 UK families showing evidence of
predisposition to melanoma. Five different germline mutations in CDKN2 were
found in six families. Three of the mutations (Met53Ile, Arg24Pro and
23ins24) have been reported previously. We have identified two novel CDKN2
mutations (88delG and Ala118Thr) which are likely to be associated with the
development of melanoma, because of their co-segregation with the disease
and their likely functional effect on the CDKN2 protein. In binding assays
the protein expressed from the previously described mutation, Met53Ile, did
not bind to CDK4/CDK6, confirming its role as a causal mutation in the
development of melanoma. Ala118Thr appeared to be functional in this assay.
Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were
detected in exon 2 of CDK4, suggesting that causal mutations in this gene
are uncommon. The penetrance of these mutant CDKN2 genes is not yet
established, nor is the risk of non-melanoma cancer to gene carriers.
相似文献
5.
Prekallikrein activation and high-molecular-weight kininogen consumption in hereditary angioedema 总被引:12,自引:0,他引:12
M Schapira L D Silver C F Scott A H Schmaier L J Prograis J G Curd R W Colman 《The New England journal of medicine》1983,308(18):1050-1053
Patients with hereditary angioedema lack C-1 inhibitor, a plasma alpha 2-glycoprotein that inhibits both the proteolytic action of C1, the activated first component of the complement system, and the activity of components of the contact phase of coagulation: kallikrein, factor XIa, and factor XIIa. Such patients have been shown to have low levels of C4 and C2, the natural substrates for C-1, but the levels were not correlated with the presence of symptoms. We studied three patients with angioedema for evidence of activation of the contact system and found that during a symptomatic period they had decreased levels of prekallikrein, a substrate for the activated forms of factor XII, and reductions in high-molecular-weight kininogen, a substrate for plasma kallikrein. These observations suggest that zymogens of the contact system are activated during attacks of hereditary angioedema and that some of the clinical manifestations may be mediated through products of this pathway, such as kinins. 相似文献
6.
Purification and characterization of two functionally distinct forms of C1 inhibitor from a patient with angioedema. 总被引:2,自引:0,他引:2
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J G Curd M Yelvington R J Ziccardi D A Mathison J H Griffin 《Clinical and experimental immunology》1981,45(2):261-270
A minority of patients with hereditary angioedema (HAE) have normal concentrations of a dysfunctional C1 inhibitor protein (C1INH) in their plasmas. We purified C1INH from the plasmas of one such patient before and during treatment with the anabolic steroid stanozolol. Both the pretreatment plasma and plasma obtained during stanozolol treatment contained varying amounts of two extremely similar C1INH proteins that were functionally distinct. The pretreatment plasma contained primarily (94%) dysfunctional C1INH that did not inactivate or complex with either purified C1s, activated Hageman factor, or kallikrein and small amounts (6%) of functionally normal C1INH. Stanozolol treatment increased the plasma concentrations of both of these proteins as well as the proportion (23%) of functional C1INH in the plasma. The purified dysfunctional and functional C1INHs had identical or nearly identical molecular sizes, charges, amino acid compositions, and amino sugar contents, and could not be distinguished physicochemically from each other or from normal C1INH. From these studies of purified C1INH proteins we concluded that HAE associated with dysfunctional C1INH is due to a defect at the structural locus for one C1INH gene and that both the dysfunctional C1INH gene and the normal C1INH gene products are present in the plasma of the affected subject. Treatment with stanozolol comparably increased the synthesis of both C1INH proteins. The disproportionate rise in the level of the normal C1INH protein is consistent with the view that it is more rapidly catabolized as a consequence of its interaction with the proteases it inactivates. 相似文献
7.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg
TPA) protocols were found to be under multigenic control. Eighty- one N2
mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were
either solidly resistant (no papillomas) or highly susceptible (> or = 7
papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite
markers to check for associations with susceptible and resistant
phenotypes. A locus on Chr 5 (Skts4) was found to control the
susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to
papilloma formation. In addition, higher than expected linkage scores were
seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is
required to establish whether genes determining papilloma formation are
located in these regions of the genome. In general, no evidence was seen
for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in
17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.
相似文献
8.
The plasma concentrations of von Willebrand factor antigen (vWF:Ag) were determined in 101 patients who had the following diagnoses: vasculitis 8 patients, systemic lupus erythematosus (SLE) 51, rheumatoid arthritis (RA) 28, asthma 7, hereditary angioedema 7. The greatest mean concentration of vWF:Ag, 469% (normal 100% +/- 50), was observed in patients with vasculitis, often without elevation of the erythrocyte sedimentation rate. The mean concentration of vWF:Ag was also increased in both SLE (277%) and RA (194%). Twenty-four patients (15 with SLE, 6 with vasculitis, 3 with RA) had vWF:Ag concentrations greater than 300%. Four of these patients died within 1 year of the date of the study. Of the 15 SLE patients, 9 had vasculitis and 2 had active glomerulonephritis. The 3 RA patients had severe disease associated with extraarticular manifestations. Elevated vWF:Ag may reflect vascular damage, while markedly elevated levels of vWF:Ag appear to indicate a poor prognosis. 相似文献
9.
Background
Overweight and obesity prevalence is rapidly rising in developing countries. The reading and understanding of nutrition information on food packages has been shown to improve food choices and instill healthy eating habits in individuals.Objective
The aim of this study was to describe the prevalence of food label usage and understanding among urban and rural adults in Zimbabwe and its association with demographic and socio economic factors.Methods
A cross sectional study was conducted on 320 adults (147 urban and 173 rural) using a validated questionnaire adapted from previous similar studies. Data were analysed using SPSS-17 statistical software.Results
A high proportion (77.2%) of the respondents read food labels. Food label reading differed significantly by educational status (p<0.05), employment status (p<0.05) and locality (p<0.05). Only 40.9% of food label readers mostly understood the information on the food labels. More urban shoppers (86.1%) read food labels than their rural counterparts (66.7%). A significant number of participants (80.6%) indicated they would like to be educated on the meaning of food labels and 80.3% preferred the nutrition information on food labels to be simplified.Conclusion
The study found above average reported reading of nutrition information on food labels with partial understanding. Efforts should be made to determine how all consumers could be made to understand the nutrition information on food labels and use it effectively in decision making. 相似文献10.
THOMAS J. A. Lehman John G. Curd Nathan J. Zvaifler Virgil Hanson 《Arthritis \u0026amp; Rheumatology》1982,25(5):556-561
We studied 31 children with systemic lupus erythematosus (SLE) and 108 first-degree relatives of the children to determine if HLA type, familial relationship to patient, or gender influenced the familial aggregation of SLE and the serologic and serum complement abnormalities associated with SLE. There were no significant relationships between the presence of antinuclear antibodies (ANA), antilymphocyte antibodies (ALA), or circulating immune complexes. Furthermore, there was no correlation between the occurrence of ANA, ALA, or circulating immune complexes with HLA type or relationship to patient. Both ANA and ALA were associated with a reduction in the mean serum C4 level, without a corresponding reduction in mean serum C3 or CH50. The reduction in mean serum C4 level with ALA occurred without regard to the subject's relationship to the patient, but the reduction in mean serum C4 level with ANA was significant only among the sisters. Because of these data, it seems that the sisters of patients with SLE are more likely than other relatives to have activation of the complement system in association with serologic abnormalities. Those sisters with ANA and ALA had the greatest amount of complement activation and may be the relatives at greatest risk for the subsequent development of SLE. 相似文献