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排序方式: 共有908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.
A specific and sensitive radioimmunoassay for the determination of levels of zalcitabine in human plasma, urine, and cerebrospinal fluid has been developed. Commercially available radiolabel and antiserum (Sigma Chemicals) were used after dilution in assay buffer. Prior to the immunoassay, standard and patient samples were subjected to solid-phase extraction on silica columns in order to obtain purified samples. The lower limit of quantitation was determined to be 1 ng/ml. Intra- and interassay variations were less than 11% for a number of quality control samples of drug in plasma and urine. Results from parallelism studies with plasma and urine demonstrated that samples outside the standard range (1 to 30 ng/ml) could be diluted by blank plasma or assay buffer, respectively. A large number of related compounds and potentially coadministered drugs were tested for cross-reactivity. Stability tests showed that heat treatment for 30 min at 60 degrees C or storage for 1 month at -30 degrees C did not affect zalcitabine concentrations in plasma or urine. The radioimmunoassay with solid-phase extraction for sample cleanup discussed here has been successfully applied in a pharmacokinetic study of a single patient, demonstrating its applicability for clinical pharmacokinetic research with zalcitabine.  相似文献   
6.
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   
7.
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   
8.
To assess long-term results, coronary and graft angiography was performed 53 to 84 months after operation in 22 of 30 consecutive patients who had undergone coronary-artery bypass grafting before 1973, and who had at least one graft patent at an early (three to nine months) postoperative study. Of the 33 grafts, 31 were patent at late study. All patients had severe symptoms before operation. Of 16 who became asymptomatic early after operation, angina pectoris later redeveloped in 11. Progression of disease in ungrafted vessels accounted for symptomatic deterioration in nine of these 11 patients. We conclude that most grafts patent several months after operation remain so for at least 4 1/2 years, and that although most patients improve symptomatically after operation, symptomatic deterioration is common in the succeeding years and is most often due to progression of disease in ungrafted vessels.  相似文献   
9.
ObjectivesAbiraterone acetate is registered for the treatment of metastatic castration-sensitive and resistant prostate cancer (mCRPC). Treatment outcome is associated with plasma trough concentrations (Cmin) of abiraterone. Patients with a plasma Cmin below the target of 8.4 ng/mL may benefit from treatment optimization by dose increase or concomitant intake with food. This study aims to investigate the cost-effectiveness of monitoring abiraterone Cmin in patients with mCRPC.MethodsA Markov model was built with health states progression-free survival, progressed disease, and death. The benefits of monitoring abiraterone Cmin followed by a dose increase or food intervention were modeled via a difference in the percentage of patients achieving adequate Cmin taking a healthcare payer perspective. Deterministic and probabilistic sensitivity analyses were performed to assess uncertainties and their impac to the incremental cost-effectiveness ratio (ICER).ResultsMonitoring abiraterone followed by a dose increase resulted in 0.149 incremental quality-adjusted life-years (QALYs) with €22 145 incremental costs and an ICER of €177 821/QALY. The food intervention assumed equal effects and estimated incremental costs of €7599, resulting in an ICER of €61 019/QALY. The likelihoods of therapeutic drug monitoring (TDM) with a dose increase or food intervention being cost-effective were 8.04%and 81.9%, respectively.ConclusionsMonitoring abiraterone followed by a dose increase is not cost-effective in patients with mCRPC from a healthcare payer perspective. Monitoring in combination with a food intervention is likely to be cost-effective. This cost-effectiveness assessment may assist decision making in future integration of abiraterone TDM followed by a food intervention into standard abiraterone acetate treatment practices of mCRPC patients.  相似文献   
10.
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   
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