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排序方式: 共有848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   
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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   
4.
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   
5.
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   
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
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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.
The human immunodeficiency virus type 1 (HIV-1) DNA PCR results of 94 dried blood spot (DBS) samples on filter paper and corresponding venous blood in EDTA obtained from infants born to HIV-1-seropositive mothers were compared. In addition, the results of HIV-1 DNA PCR on DBS and the HIV-1 RNA PCR from plasma of 70 paired samples were compared. A 100% specificity and a 95% sensitivity for HIV-1 DNA PCR on DBS compared with results for venous blood were observed for the 94 paired samples. The results of the DBS HIV-1 DNA PCR and HIV-1 RNA PCR of 70 corresponding plasma samples correlated perfectly (100%). The DBS HIV-1 DNA PCR method proved reliable for HIV-1 detection.  相似文献   
9.
Placental inflammation and perinatal transmission of HIV-1   总被引:2,自引:0,他引:2  
The effect of placental membrane inflammation on mother-to-child transmission (MTCT) of HIV-1 is reported. Placentas from HIV-1-infected women were examined as part of a perinatal HIV-1 project in Mombasa, Kenya. Polymerase chain reaction analysis was used to test for HIV-1 in the infants at birth and at 6 weeks. The maternal HIV-1 seroprevalence was 13.3% (298 of 2,235). The overall rate of MTCT of HIV-1 was 25.4%; polymerase chain reaction analysis revealed that of the 201 infants 6.0% (12) were already HIV-1-positive at birth (intrauterine transmission) and 19.4% (39) were infected during the peripartum period or in early neonatal life (perinatal transmission). The prevalence of acute chorioamnionitis was 8.8%, that of deciduitis was 10.8%, and that of villitis was 1.6%. Acute chorioamnionitis was independently associated with peripartum HIV-1 transmission but not with in utero MTCT (17.9% vs. 6.7%, respectively; adjusted odds ratio, 3.9; 95% confidence interval, 1.2-12.5; p =.025). Other correlates of perinatal MTCT were presence of HIV in the genital tract and in the baby's oral cavity and a high maternal viral load in peripheral blood. The adjusted population attributable fraction of 12.8% (95% confidence interval, 1.5%-22.8%) indicated that approximately 3% of MTCT could be prevented if acute chorioamnionitis was eliminated. We suggest that further research on the role of antimicrobial treatment in the prevention of chorioamnionitis and the reduction of peripartum MTCT needs to be performed.  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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