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991.
Hp相关胃炎患者血清表皮生长因子(ECG)和β2—微球蛋白(β2—MG)水平研究 总被引:1,自引:0,他引:1
目的探索EGF和β2-MG在CSG -CAG -GC演变模式中的变化规律 ,探讨Hp对EGF和β2-MG有无影响。方法应用尿素酶试验法、血清学试验法和组织学诊断法 ,进行Hp检查 ,应用放射免疫法检测血清EGF及β2-MG水平。结果(一)EGF水平(μg/L) :(1)按CSG -CAG -GC逐渐升高 ,依次为0.3229±0.225 ,0.8823±0.2549,1.3999±0.8935,GC组高于CSG组 (P<0.01) ,也高于CAG组 (P<0.05) ,CAG组高于CSG组 (P<0.01)。(2)CSG患者Hp(+)组 (0.2404±0.1103)低于Hp( -)组 (0 .4492±0.2931) (P<0.01) ;CAG患者Hp(+)组 (0 .8119±0.279)低于Hp(- )组(1.0056±0.1704) ,GC患者Hp(+)组 (1.159±0 .9229)低于Hp(- )组(1 .4963±0 .9127) ,均无统计学差异 (P>0.05)。(二 ) β2-MG水平 (mg/l) :(1)按CSG -CAG -GC顺序增高 ,依次为 :1.659±0.4321 ,1 .9661±1 .0802,2.3431±0 .5951 ,GC组高于CSG组 (P<0.01),CAG组高于CSG组 ,GC组高于CAG组 ,均无统计学意义 (P>0.05)。(2)同一胃病Hp( +)组与Hp( -)组比较血清β2-MG水平均无明显差异 (P>0.05)。结论按CSG -CAG -GC ,EGF水平逐渐升高 ,β2-MG有此种趋势。Hp有降低EGF的作用 ,Hp对β2-MG水平无明显影响 相似文献
992.
993.
The current concept of breast cancer treatment arises from Fisher's theory that operable breast cancer has distant micrometastasis at its very early stages. Since it is the presence of systemic diseases or micrometastasis that determines the final outcome, variation in local treatment would not affect survival. Fisher's theory led to a change in local treatment, from Halsted's radical mastectomy to breast-conserving therapy (BCT), and the introduction of adjuvant systemic treatment. As part of the job of surgery is replaced by radiation therapy in local control, the efficacy and side effects of radiation should be carefully monitored. The recently published results of 20-year follow-up in 2 important studies confirm that BCT achieves equal survival compared to mastectomy in women with early breast cancers, even after all causes of mortality have been considered. The introduction of sentinel lymph node biopsy has further decreased the adverse impact of breast cancer treatment on women. As variation in local control does not affect survival, more efforts are being put into developing adjuvant systemic treatment with curative intent. Adjuvant chemotherapy has been demonstrated to substantially affect the survival of women with early breast cancers. It is now apparent from numerous studies that adjuvant therapy improves survival in all subgroups of women with early breast cancer, although the absolute benefit varies depending on axillary lymph node status, tumor size, and other prognostic factors. This article reviews recent advances in the management of primary breast cancer, including: long-term follow-up after BCT; side effects of radiation therapy in BCT; post-mastectomy radiotherapy; sentinel node biopsy; adjuvant hormone therapy; and chemotherapy, including new strategies such as the incorporation of taxanes, dose-dense chemotherapy schedules, and the use of aromatase inhibitors in place of, or in addition to, tamoxifen. 相似文献
994.
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996.
CD24 expression on human keratinocytes 总被引:4,自引:0,他引:4
Pedro Redondo Jesús García-Foncillas Iouri Okroujnov Iñigo de Felipe Emilio Quintanilla 《Experimental dermatology》1998,7(4):175-178
Abstract: CD24 or Nectadrin is a cell surface glycoprotein expressed in pre-B lymphocytes, T lymphocytes, neurons, muscle cells and carcinoma cells. Its function is not completely known, but it has been suggested that it is involved in cell adhesion and signalling. CD24 has recently been identified as the human molecule homologous to the murine heat-stable antigen (HSA). HSA is expressed by murine keratinocytes and delivers costimulatory signals in T-cell activation. Long-term cultures of normal human keratinocytes (HKC) were obtained from skin of human female breast sections and either left untreated or were treated with phorbol-12-myristate-13-acetate (PMA) at 10–100 ng/ml, calcium 0.5–2 mM or IFN-γ 100–1000 U/ml, for 24–48 h. Using RT-PCR and flow cytometry we showed that HKC express low levels of CD24 even under basal conditions, and the treatment with calcium, PMA or IFN-γ increased levels of CD24 mRNA and protein. To the best of our knowledge, this is the first report to measure CD24 expression and production by cultured HKC in basal conditions and after stimulation. Further studies are needed to determine biological and therapeutical relevance of these findings. 相似文献
997.
The transport and phosphorylation of gluconate in E. coli occurs through two systems (GntI and GntII) which duplicate activities. bioH-asddeletion mutants do not grow on media with gluconate as sole carbon source because they lack the GntI system and do not express GntII. Although E. coli C177 is a Δ(bioH-asd) mutant, it carries the pyrB linked mutation gnt177 that enables it to metabolize this substrate through inducible expression of the GntII system. Several gntS derivatives which are unable to grow on gluconate were isolated from E. coli C177 by spontaneous curing of the transposon Tn10 previously inserted at the gntS locus (zjf::Tn10, min 95.3). A representative gntS mutant, E. coli TI141A retained the ability to take up gluconate but had lost the thermosensitive gluconokinase activity (gene gntV, min 96.9). Furthermore, it could be demonstrated that gntV is repressed in E. coli TI141A. The results indicate that gntS might specify a trans-acting positive regulator involved in the control of at least the expression of the thermosensitive gluconokinase (GntII), instead of a gluconate uptake system as it was previously postulated. Likewise, these results can be used to reconsider whether the locus altered by the gnt177 lesion is allelic with that of the GntII permease instead of a regulator, as it was originally postulated. 相似文献
998.
本文报告了4例肾移植患者术后1-3个月出现高尿酸血症并形成了移植肾、输尿管尿酸盐结石,结合复习文献探讨了环孢素A(CsA)引起高尿酸血症的可能机制和促成结石形成的因素。通过回顾4例患者成功治疗的体验,讨论了移植肾、输尿管尿酸结石预防及治疗的选择。 相似文献
999.
Spermatogenic function was studied in 10 patients, previously diagnosed as having primary hypothyroidism, in whom a state of hypothyroidism has been induced by discontinuation or a decrease in treatment with levothyroxine over at least one spermatogenic cycle. Most of the patients had fathered children before the study. When the results obtained in the hypothyroid state were compared with those from a group of 16 controls with proven fertility, slight anomalies were observed; these were characterized by a decrease in seminal volume (p less than 0.05), progressive forward motility (p less than 0.01), and the cumulative percentage of mobile forms (p less than 0.01). There were no anomalies in sperm density or in the percentage of spermatozoa with normal morphology. No alterations in circulating levels of testosterone and gonadotropins existed. Induction of hypothyroidism did not lead to seminal or hormonal modifications compared with the same patients in a situation of euthyroidism. Short-term postpuberal hypothyroidism did not cause seminal alterations sufficiently intense to induce male infertility. 相似文献
1000.
The pharmacokinetics of dibenzylamine administered in a sustained drug delivery system with cefazolin was studied after i.m. administration of a dose of 1250 mg to healthy volunteers. The serum and urine levels of dibenzylamine were determined by a GLC technique using a specific nitrogen-phosphorus detector. Characterization of the kinetic parameters was performed by applying compartmental and non-compartmental analysis. Dibenzylamine was found to reach concentrations close to 300 ng ml-1 approximately 5 h after administration. The elimination constant had a value of 0.832 +/- 0.821 h-1 (mean +/- S.D.), which is higher than the release constant of the derivative (0.109 +/- 0.072 h-1) (mean +/- S.D.). These results show that release of dibenzylamine may be considered the limiting kinetic process, which governs the elimination of the product from the organism. Only a small amount of dibenzylamine is excreted in urine unchanged 3.43 +/- 3.28 per cent (mean +/- S.D.). Using the pharmacokinetic parameters calculated for dibenzylamine, a prediction has been made of the concentrations reached in a multiple dosage regimen after administration of a dose of 1250 mg every 24 h. The accumulation factor was 1.09. 相似文献