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71.
目的:应用3.0TMRI从影像学角度探讨缺血性脑血管病与鼻旁窦炎性病变的关系及鼻旁窦炎性病变的MRI表现。方法:①分组及检测:2006-10/2007-08河北医科大学第二医院收治经临床及影像学证实为缺血性脑血管病患者218例为病例组,健康体检者218例为对照组,应用美国GE公司Signa Excite HD 3.0T高场强MR扫描仪常规行MRI及MRA检查。②评估指标:MRI图像观察以轴位T2-FSE、轴位T1-FLAIR序列为主,辅以轴位T2-FLAIR、矢状位T1-FLAIR序列,观察并记录脑实质MRI表现、鼻旁窦有无炎性病变。MRA图像观察以MIP重组后图像为主,辅以MRA源图像,观察并记录颅内血管异常情况。主要观察指标包括额窦、筛窦、蝶窦、上颌窦受累情况,各窦病变类型(黏膜增厚、炎性积液、黏膜下囊肿)及相应的MRI表现。结果:①病例组所有患者前循环及后循环系统血管均存在不同程度的动脉粥样硬化改变,143例患者脑实质出现缺血性病变;对照组脑实质及脑血管均未见异常改变。②病例组鼻旁窦有病变者123人次(56.4%),上颌窦病变96例,筛窦病变58例,蝶窦病变30例,额窦病变15例;对照组鼻旁窦有病变者54人次(24.8%),上颌窦病变8例,筛窦病变34例,蝶窦病变2例,额窦病变4例。病例组鼻旁窦炎性病变明显较对照组多(χ2=45.281,P=0.000)。相关系数C=0.91。结论:缺血性脑血管病患者鼻旁窦炎性病变发病率高,缺血性脑血管病与鼻旁窦炎性病变间有一定的相关性。  相似文献   
72.
AIM:To investigate whether celiac disease(CD)patients with tissue-transglutaminase antibody(tTGA)≥100 U/mL are different from patients with lower tTGA levels.METHODS:Biopsy-proven(MarshⅢ)pediatric CD patients(n=116)were prospectively included between March 2009 and October 2012.The biopsies were evaluated by a single pathologist who was blinded to all of the patients’clinical data.The patients were distributed into 2 groups according to their tTGA level,which was measured using enzyme-linked immunoassay:tTGA≥100 U/mL and Ttga<100 U/mL.The patients’characteristics,symptoms,human leukocyte antigen(HLA)genotype and degree of histological involvement were compared between the 2 groups.RESULTS:A total of 34(29.3%)children had tTGA values<100 U/mL and 82(70.7%)tTGA levels of≥100 U/mL.Patients with high tTGA levels had lower average body weight-for-height standard deviation scores(SDS)than did patients with tTGA<100 U/mL(-0.20±1.19 SDS vs 0.23±1.03 SDS,P=0.025).In the low tTGA group,gastrointestinal symptoms were more common(97.1%vs 75.6%,P=0.006).More specifically,abdominal pain(76.5%vs 51.2%;P=0.012)and nausea(17.6%vs 3.7%,P=0.018)were more frequent among patients with low tTGA.In contrast,patients with solely extraintestinal manifestations were only present in the high tTGA group(18.3%,P=0.005).These patients more commonly presented with aphthous stomatitis(15.9%vs 0.0%,P=0.010)and anemia(32.9%vs 11.8%,P=0.019).In addition,when evaluating the number of CD-associated HLA-DQ heterodimers(HLA-DQ2.5,HLA-DQ2.2 and HLA-DQ8),patients with low tTGA levels more commonly had only1 disease-associated heterodimer(61.8%vs 31.7%,P=0.005),while patients with high tTGA more commonly had multiple heterodimers.Finally,patients with tTGA≥100 U/mL more often had a MarshⅢc lesion(73.2%vs 20.6%,P≤0.001)while in patients with low tTGA patchy lesions were more common(42.4%vs6.8%,P≤0.001).CONCLUSION:Patients with tTGA≥100 U/mL show several signs of more advanced disease.They also carry a larger number of CD  相似文献   
73.
AIM: To demonstrate the range of applying laser angioplasty after unsuccessful recanalization of the superficial femoral artery (SFA) with conventional interventional techniques. MATERIALS AND METHODS: In a prospective trial in 94 cases with occlusion of the SFA and formerly unsuccessful conventional percutaneous transluminal angioplasty, laser angioplasty for recanalization was applied. The average length of the SFA was 17.5 cm (range 4–36 cm). The recanalization attempt was made using the crossover technique in 78 patients, in eight patients with the antegrade technique and in another eight patients using the transpopliteal technique. The primary recanalization attempt was performed with Terumo wires (curved and straight) as well as different catheters (Multipurpose/Vertebralis/Cobra). the unsuccessful recanalization attempt the laser catheter was applied. RESULTS: The application of laser angioplasty demonstrated a successful recanalization of the SFA in 76/94 patients (80.9%). In 18 patients (19.1%) the recanalization was not possible even with percutaneous transluminal laser angioplasty (PTLA). The reason for the unsuccessful PTLA was in 10 cases due to obstructing calcified material, which was resistant to PTLA application. In four cases obstructing calcifications caused the laser catheter to be positioned in subintimal tissue, resulting in perforation occlusion of the SFA. In another four patients there was an aberrant anatomy of the SFA which resulted in a direct vessel injury after advancing the laser catheter. After a follow-up period of 12 months primary, primary-assisted and secondary patency rates were 50.0%, 65.8% and 73.7%, respectively. DISCUSSION: In primarily unsuccessful recanalization of the SFA, PTLA allows in After 80% of cases a successful recanalization of the SFA. The technical success rate and the patency rate support the application of PTLA. (Int J Cardiovasc 2000; 3: 153–160)  相似文献   
74.
Previous work has shown failure of engraftment in lethally irradiated dogs when autologous marrow was depleted of Ia-positive cells with an anti-Ia antibody and complement before infusion. In the current study, we have utilized an avidin-biotin immunoadsorption procedure to obtain a population of highly enriched Ia-positive cells for autologous bone marrow transplantation in dogs given lethal irradiation. Dog marrow cells (2.4 to 7.0 X 10(9) cells) that contained 8.6% to 19.9% Ia- positive cells were treated successively with monoclonal antibody 7.2, which reacts with a framework determinant of Ia-antigen, and biotin- conjugated goat antimouse immunoglobulin. These treated cells were passed over a column of avidin-Biogel (polyacrylamide) and the adherent cells removed by mechanical agitation. Seven lethally irradiated dogs were transplanted with 5.9 to 33.4 X 10(6) recovered adherent cells per kilogram of which 69.0% to 88.0% were Ia-positive. All dogs had hematologic recovery; six are alive and well with durable engraftment and one died on day 15 posttransplant. They are immunologically normal as determined by lymph node and bone marrow biopsies, lymphocyte function, and immunophenotyping of peripheral blood and bone marrow cells. These data provide further evidence that canine hematopoietic stem cells express Ia-like antigens and that these cells are capable of complete hematopoietic and immunologic reconstitution in an autologous model.  相似文献   
75.
Contribution of host-related cytokine release in the course of pretransplant conditioning to early tissue damage and induction of acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT) has been shown in experimental models. We performed a clinical phase I/II trial applying a monoclonal antibody neutralizing human tumor necrosis alpha (TNF alpha) during pretransplant conditioning as additional prophylaxis in high-risk patients admitted to allogeneic BMT; TNF alpha serum levels and clinical courses in 21 patients receiving anti-TNF alpha prophylaxis were compared with data from 22 historical controls. Absence of significant release of TNF alpha in the period of busulphan (BUS) treatment, but significant induction of TNF alpha by total body irradiation (TBI) and cyclophosphamide (CY) conditioning were correlated with significantly earlier onset of acute GVHD in patients receiving TBI/CY regimens as compared with BUS/CY-treated patients. Prophylactic application of monoclonal anti-TNF alpha seemed to postpone onset of acute GVHD from day 15 to day 25 (P < .05) after TBI/CY and from day 33 to day 53 after BUS/CY (P < .10) conditioning. Application of monoclonal anti-TNF alpha in low and intermediate doses was safe and not associated with an increased incidence of infectious or hematologic complications. Thus, our data provide indirect and direct evidence for involvement of conditioning-related cytokine release in induction of early acute GVHD in the clinical setting and support further investigation of this novel approach in randomized trials.  相似文献   
76.
Ehninger  G; Schuler  U; Renner  U; Ehrsam  M; Zeller  KP; Blanz  J; Storb  R; Deeg  HJ 《Blood》1995,85(11):3247-3249
In a canine model we investigated the toxicity and pharmacokinetics of a water soluble busulfan preparation. Busulfan was dissolved in dimethylsulfoxide (DMSO) and administered either orally or intravenously in a single dose of 1 mg/kg. The application in either preparation was well tolerated. In seven dogs, peak levels in the range of 730 ng/mL to 1,000 ng/mL were measured after intravenous injection with an area under curve (AUC) of 75 ng.h/kg.mL to 146 ng.h/kg.mL. It was of note that even the oral administration of the same busulfan preparation resulted in AUC values in the same range as observed after parenteral application. The absorption rate of busulfan tablets in our model was as unpredictable as documented in clinical trials. On the basis of the present study, clinical trials using busulfan dissolved in DMSO given either intravenously or orally appear warranted. This approach should lead to predictable blood levels, reduced toxicity, and increased efficacy of busulfan-containing regimens.  相似文献   
77.
Twenty-four patients whose cells contained a variety of 11q23 rearrangements, including translocations, insertions, and an inversion, were studied using fluorescence in situ hybridization with cosmid, phage, and plasmid probes mapped to 11q22-24. In 17 patients, the breakpoints of the common 11q23 translocations involving chromosomes 4, 6, 9, and 19 as well as some uncommon translocations involving 3q23, 17q25, 10p11, and an insertion 10;11 were all located in the breakpoint cluster region of the MLL gene, regardless of age, phenotype of disease, or involvement of a third chromosome. The breakpoints in 11q23 in the other 7 patients with a t(7;11)(p15;q23), inv(11)(p11q23), t(4;11)(q23;q23), der(5)t(5;11)(q13;q23), ins(10;11)(p11;q23q24), t(11;14)(q23;q11), or t(11;18;11) (p15;q21;q23) were located either centromeric to CD3D or telomeric to THY1. Thus, although most 11q23 rearrangements, involve the same breakpoint cluster region of MLL, there is heterogeneity in the breakpoint in some of the rare rearrangements.  相似文献   
78.
The effects of recombinant canine stem cell factor (rcSCF) on hematopoiesis were studied in normal dogs and in dogs given otherwise lethal total body irradiation (TBI) without marrow transplant. Results were compared with previous and concurrent data with recombinant granulocyte colony-stimulating factor (rG-CSF). Four normal dogs received 200 micrograms rcSCF per kilogram body weight daily either by continuous intravenous infusion for 28 days (n = 2) or by subcutaneous (SC) injection in two divided doses for 20 days (n = 2). All dogs showed at least a twofold increase in peripheral blood neutrophil counts starting approximately 7 days after the initiation of treatment. Hematocrit level and monocyte, lymphocyte, eosinophil, reticulocyte, and platelet counts were not elevated. Marrow sections after rcSCF treatment showed panhyperplasia. The only toxicity was facial edema during the first few days of rcSCF administration, presumably caused by mast cell stimulation. Ten dogs were given 400 cGy TBI at 10 cGy/min from two opposing 60Co sources. They were given no marrow infusion and received 200 micrograms/kg/d rcSCF SC in two divided doses for 21 days starting within 2 hours of TBI. Five of the 10 dogs showed complete and sustained hematopoietic recovery and survived as compared with 1 of 28 control dogs not receiving growth factor (P < .005). RcSCF treatment allowed for hematopoietic recovery in two of seven dogs administered 500 cGy of TBI but in none of five dogs given 600 cGy of TBI. Results with rcSCF are similar to those obtained with rG-CSF. The rate of neutrophil recovery in rcSCF-treated dogs after 400 cGy TBI was not different from that of rG-CSF-treated dogs (P = .65), but the rate of platelet recovery was faster (P = .06) in the rcSCF-treated animals. Combined treatment with rcSCF and rcG-CSF after 500 cGy TBI did not result in strongly improved survival as compared with results obtained with either factor alone.  相似文献   
79.
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