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排序方式: 共有858条查询结果,搜索用时 15 毫秒
1.
目的 探讨血管新生指标CD34、CD31、vWF、Ⅳ型胶原纤维及层粘连蛋白在肝细胞肝癌(HCC)中的表达及意义 ,同时比较上述几种血管新生因子与增殖细胞核抗原 (PCNA)、病理指标及预后的相关性 ,以便筛选出有效的临床预后指标。方法 采用免疫组化方法 ,对 5 3例肝细胞肝癌的标本进行CD31、CD34、vWF、Ⅳ型胶原纤维及层粘连蛋白的染色、计数 ,并用检测数据与患者的临床资料进行统计分析。结果 统计染色的血管面积后发现 ,CD34与多种临床病理指标无相关性 ;CD31与肝内门静脉浸润相关 ;vWF与肿瘤的TNM分期及肝内门静脉浸润呈正相关 ;CollⅣ与肝内门静脉浸润呈正相关、与术后生存期呈负相关 ;Lam与肝硬化及术中出血量呈负相关、与术后生存期呈正相关。PCNA与肿瘤TNM分期有关。结论 在HCC中 ,CollⅣ、vWF、及CD31为肝细胞肝癌的有效血管新生及预后指标 ;Lam则与肝硬化及术中出血相关 ;PCNA指数肿瘤分期有关 ;CD34不能用作血管新生或预后指标  相似文献   
2.
Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Membrane flow within the myelin sheath in IDPN neuropathy   总被引:1,自引:0,他引:1  
This report describes some aspects of beta,beta'-iminodipropionitrile (IDPN) neuropathy in rats as observed by ultrastructural methods and X-ray diffraction. Light microscopy shows gross swelling of the axons in proximal lumbar spinal roots 8 days after intraperitoneal injection of IDPN. Mean axon cross-sectional area and mean axon perimeter increased to 280% and 160% of their control values, respectively. At the same time, myelin membrane packing was not visibly disturbed. In addition, X-ray diffraction patterns, recorded under physiological conditions, demonstrate that the myelin lipid bilayer thickness and widths of the aqueous spaces between bilayers did not change. Related observations are made on posterior tibial nerve (PNS myelin) and ventral spinal cord (CNS myelin). The various observations together are interpreted in terms of a fluid myelin membrane. It is proposed that the myelin membrane flows during axon swelling even though normal membrane-membrane contacts are maintained within the sheath. Membrane flow and slippage between membranes are explained in terms of a molecular model of the myelin multilayer.  相似文献   
4.
Summary. In a randomized controlled study of wound suction drainage after transverse suprapubic incision for lower-segment caesarean section no significant advantages could be demonstrated for routine drainage in terms of wound infection, haematoma formation, duration of hospital stay or analgesic requirements.  相似文献   
5.
Vascular complications of pancreatic transplantation: MR evaluation   总被引:8,自引:0,他引:8  
Krebs  TL; Daly  B; Wong  JJ; Chow  CC; Bartlett  ST 《Radiology》1995,196(3):793
  相似文献   
6.
Elevated blood pressure is an important risk factor for renal-, cerebro- and cardiovascular diseases. We used an efficient discordant sib-pair ascertainment scheme to investigate the impact of the distal end of the long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing genes for the alpha1B and beta2 adrenergic receptors and the dopamine receptor type 1A on variation of systolic blood pressure in young Caucasians. We measured eight highly polymorphic markers spanning this positional candidate gene-rich region in 427 individuals from 55 three-generation pedigrees containing 69 discordant sibling pairs, and calculated multipoint identity by descent (MIBD) probabilities. The results of genetic linkage and association tests indicate that the region between markers D5S2093 and D5S462 is significantly linked to one or more polymorphic genes influencing interindividual variation in systolic blood pressure levels. Since the alpha1B adrenergic receptor and dopamine receptor type 1A genes are located close to these markers, these data suggest that genetic variation in one or both of these G protein-coupled receptors, which participate in the control of vascular tone, plays an important role in influencing interindividual variation in systolic blood pressure levels.   相似文献   
7.
HLA antigens were investigated in 41 Sicilian patients with ulcerative colitis and in 151 healthy controls. Frequencies of HLA-B5 and DR2 were increased in the group of patients with ulcerative colitis whereas the DR3 antigen frequency was decreased. However the corrected p values were not significant. Thus, present results indicate that in ulcerative colitis HLA linked genetic factors play a marginal role, if any.  相似文献   
8.
Hypomorphic mutations of the MRE11 gene are the hallmark of the radiosensitive ataxia-telangiectasia-like disorder (ATLD). Here, we describe a new family with two affected siblings, ATLD5 and ATLD6, now aged 37 and 36, respectively. They presented with late onset cerebellar degeneration slowly progressing until puberty and absence of telangiectasias, and were cancer-free. Both patients were wild-type for ATM and NBS1, but compound heterozygotes for MRE11 gene mutations [1422C-->A, T481K; 1714C-->T, R571X]. The 1422C-->A allele was inherited from the mother, whereas the 1714C-->T, allele paternally inherited, was apparently null as a result of nonsense-mediated mRNA decay (NMD). Interestingly, the 1714C-->T mutation is the same as previously identified in an unrelated English ATLD family (probands ATLD3 and ATLD4), suggesting an important role for NMD in saving potentially lethal mutations. Lymphoblastoid cell lines (LCLs) derived from ATLD5 and ATLD6 were normal for ATM, but defective for Mre11, Rad50 and Nbs1 (the MRN complex) protein expression. Their response to gamma-radiation was abnormal, as evidenced by the enhanced radiosensitivity, attenuated autophosphorylation of ATM-S1981 and phosphorylation of the ATM targets p53-S15 and Smc1-S966, failure to form Mre11 nuclear foci and defective G1 checkpoint arrest. The fibroblasts, but not LCLs, from ATLD5 and ATLD6 showed an impaired ATM-dependent Chk2 phosphorylation. These findings further underscore the interconnection between ATM activity and MRN function, which rationalizes the clinical similarity between ataxia-telangiectasia (A-T) and ATLD.  相似文献   
9.
CAMPATH-1H IN RHEUMATOID ARTHRITIS--AN INTRAVENOUS DOSE-RANGING STUDY   总被引:1,自引:0,他引:1  
Forty-one patients with active and refractory rheumatoid arthritis(RA) received a total of 100, 250 or 400 mg of CAMPATH-1H (CAMPATHis a trademark of Glaxo-Wellcome group companies, registeredin the US Patent and Trademark Office) over 5 or 10 days inan open, uncontrolled study. Following therapy, patients weremonitored for adverse effects and disease activity for 6 months.Therapy was associated with prolonged peripheral blood lymphopeniain all dosing cohorts. During the month immediately followingtherapy, lymphopenia was most profound in the 400 mg cohorts.The first dose of monoclonal antibody (Mab) was associated witha ‘flu’-like syndrome, more pronounced at higherinitial doses. One patient developed haemolytic-uraemic syndrome.There were a number of dose-related infections during the earlypost-treatment period and one fatal opportunistic infectionwhich followed additional immunosuppressive therapy. Antiglobulinresponses developed in 9 of 31 patients tested. The majorityof patients showed symptomatic improvement following therapyand 20% of patients maintained a 50% Paulus response at 6 months,all of whom were in the 250 or 400 mg cohorts. CAMPATH- 1H appearsto be an effective treatment for RA. Allowing for the smallnumber of patients treated, infections were more common withhigher doses, although this was not true for adverse eventsoverall, and therapeutic responses were more sustained at higherdosing levels. The broad specificity of CAMPATH- 1H may be appropriatefor the immunotherapy of RA and future studies should aim todefine a dose with an optimal therapeutic ratio. KEY WORDS: CAMPATH-1H, Rheumatoid arthritis, Immunotherapy, Monoclonal antibody, Antiglobulin response  相似文献   
10.
Background: Ifosfamide has important activity in pretreated soft tissue sarcomas (STS), and recent data support a clinically significant dose-response relationship for this agent. Administration by continuous infusion and hematopoietic support have rendered dose intensification regimens possible by reducing both hematologic and non-hematologic toxicities. The optimal dose and schedule of ifosfamide when given at high doses remain to be defined. In a previous phase I study, we demonstrated the feasibility of a continuous infusion (c.i.) high-dose ifosfamide (HDI) regimen in the ambulatory setting for patients with advanced solid tumors. The objective of the present phase II study was to assess the antitumor activity and toxicity of such a schedule in patients with advanced pretreated STS.Patients and methods: Thirty-eight patients with advanced and/or metastatic STS, all pretreated with an anthracycline with or without standard-dose ifosfamide, were treated. Ifosfamide was given by c.i. at a dose of 3.5 g/m2/day over four consecutive days, with equidose mesna uroprotection over five days. G-CSF was added at a dose of 200 µg/m2/day subcutaneously from day 6 to day 12. Cycles were repeated every three weeks in the outpatient setting.Results: A total of 159 cycles of therapy were given (median 4 per patient, range 3–6). Treatment compliance was generally satisfactory. The major toxicity was hematologic, with six febrile neutropenic episodes requiring hospitalisation and parenteral antibiotics. Acute renal failure occurred in one patient after three cycles of therapy; central nervous system toxicity was mild. An overall response rate of 39% was observed (95% confidence interval, 26% to 55%), with one complete and 14 partial remissions. All but one of the responder patients had previously received standard-dose ifosfamide. The median response duration was nine months (range 5–21+ months), and the overall median survival ranged from 6–30+ months (median 13 months).Conclusions: High-dose ifosfamide is an active regimen in anthracycline- pretreated STS. Future clinical trials should be aimed at evaluating the impact of different administration schedules on clinical response and outcome. The potential role of HDI as front-line chemotherapy as well as in the adjuvant treatment of STS needs to be investigated in randomized trials.  相似文献   
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