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1.
包含颈外静脉的颈阔肌肌皮瓣修复口腔癌切除后缺损   总被引:1,自引:0,他引:1  
目的探讨将颈外静脉包含在颈阔肌肌皮瓣内修复口腔癌切除后缺损的手术方法。方法先形成蒂在颌缘下包含颈外静脉的颈阔肌肌皮瓣,待口腔肿瘤切除后,将肌皮瓣经口底隧道引入口腔修复缺损。结果临床应用17例,肌皮瓣均无血运障碍,100%存活,其中有2例发生口面痿,经换药后痿口完全闭合。结论将颈外静脉包含在颈阔肌肌皮瓣内有助于肌皮瓣血循环的改善和存活率的提高。  相似文献   
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This study reports on beta 2-microglobulin (beta 2M) deposits in the skin of 12 uremic patients and three kidney transplant recipients compared with eight healthy controls. Uremic patients were treated by hemodialysis (HD), hemofiltration (HF), hemodiafiltration (HDF), or continuous ambulatory peritoneal dialysis (CAPD) for a period lasting from 1 to 19 years. Congo red staining of the skin was negative in patients and controls. However, immunofluorescent staining with an anti-beta 2-microglobulin monoclonal antibody was positive in the skin of all patients and of six of the eight controls. Beta 2M skin deposition is more intense in patients than in controls and increases with patient age and the duration of dialysis. A stron correlation is observed between the extent of skin beta 2M deposits and clinical manifestations due to beta 2M deposits in internal organs. However, no correlation is found between beta 2M skin deposits and sex or beta 2M serum levels.  相似文献   
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The aim of this study is to raise up the effect of surgical thrombectomy among other alternative therapies. This retrospective study reports 6 patients (mean age 63 years) admitted with phlegmasia cerulea dolens. All patients underwent surgical venous thrombectomy associated with infracava filter insertion in 2 cases. One patient died in the early postoperative course. In all other cases we noticed good early and late outcome both on clinical examination and duplex scanning assessment. In conclusion, surgical venous thrombectomy can be considered as a good and efficient procedure in the presence of phlegmasia cerulea dolens in order to relieve ischemia and to prevent whenever possible severe chronic venous disorders. However, fibrinolytic therapy might achieve as good results as surgery. Thus, the latter is to be reserved to very severe veinous ischemia with limb loss threatening where fibrinolytic therapy fails or is contre-indicated.  相似文献   
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目的:探讨莱菔硫烷(sulforaphane,SFN)对氧化低密度脂蛋白(oxidized low-density lipoprotein,ox-LDL)诱导血小板活化的影响及其可能的分子机制。方法:在体外实验中,将健康人纯化血小板与不同浓度的SFN(1.0、2.5、5.0μmol/L)共同孵育40 min,然后用ox-LDL激活血小板20 min,并检测血小板活化的指标,包括CD62P的表达、胞内血小板因子4(platelet factor4,PF4)和趋化因子配体5(chemokine ligand 5,CCL5)的释放水平。机制上,用Western blot蛋白免疫印迹法检测血小板肉瘤酪氨酸激酶(sarcoma tyrosine kinase,Src)及其下游的脾酪氨酸激酶(spleen tyrosine kinase,Syk)磷酸化水平;用活性氧(reactive oxygen species,ROS)检测试剂盒测定胞内总ROS水平。结果:ox-LDL诱导的血小板CD62P的表达以及PF4和CCL5的释放水平均可被SFN显著抑制(P <0.05);SFN显著下调ox-LD...  相似文献   
7.
Campylobacter jejuni infection of mice initiated by intranasal administration was investigated as a potential model for studies of pathogenesis and immunity. By using a standard challenge (5 x 10(9) CFU), C. jejuni 81-176 was more virulent for BALB/c (72% mortality) than for C3H/Hej (50%), CBA/CAJ (30%), or C58/J (0%). Intranasal challenge of BALB/c was used to compare the relative virulence of three reference strains; C.jejuni 81-176 was more virulent (killing 83% of challenged mice) than C. jejuni HC (0%) or C. coli VC-167 (0%). The course of intranasally initiated C. jejuni 81-176 infection in BALB/c was determined. C. jejuni was recovered from the lungs, intestinal tract, liver, and spleen at 4 h after challenge, the first interval evaluated. After this initial interval, three distinct patterns of infection were recognized: (i) a progressive decline in number of C. jejuni CFU (stomach, blood, lungs), (ii) decline followed by a second peak in the number of organisms recovered at 2 or 3 days postchallenge (intestine, liver, mesenteric lymph nodes), and (iii) persistence of approximately the same number of C.jejuni CFU during the course of the experiment (spleen). Intranasally induced infection initiated with a sublethal number of bacteria or intranasal immunization with killed Campylobacter preparations resulted in both the generation of Campylobacter antigen-specific immune responses and an acquired resistance to homologous rechallenge. The model was used to evaluate the relative virulence of nine low-in vitro-passage (no more than five passages) isolates of C. jejuni species from patients with diarrhea. The patient isolates were differentially virulent for mice; one killed all exposed mice, three were avirulent (no deaths) and the remainder showed an intermediate virulence, killing 17 to 33%. Mouse virulence of Campylobacter strains showed a trend toward isolates originating from individuals with watery diarrhea; however, no association was found between mouse virulence and other signs or symptoms. There were no observed relationships between mouse virulence and bacterial Lior serotype or Fla polymorphic group. Intranasal challenge of BALB/c with C. jejuni is a useful model for the study of infection and vaccination-acquired immunity to this agent.  相似文献   
8.
目的:对耳大神经及腮腺筋膜解剖进行再认识,由此改良腮腺切除手术方法。方法:解剖成人尸体10侧,术中活体解剖20侧,对耳大神经和腮腺筋膜的解剖要素进行观察。根据观察结果进行改良腮腺切除术14例,即在腮腺筋膜表面翻瓣后,由前向后另翻腮腺筋膜瓣,切除腮腺后将筋膜瓣复位缝合,完整保留耳大神经和腮腺筋膜。结果:耳大神经在下颌角水平之上0-2cm依次分耳后、耳垂、耳前支,神经主干末段和分支起始段均分布于腮腺筋膜浅层表面,后者致密,其致密纤维包裹在神经周围。改良手术后2例(14.3%)发生轻度Frey’s综合征,无1例发生术区皮肤长期麻木、长期面瘫、涎瘘及肿瘤复发。结论:耳大神经各分支和腮腺筋膜具有不可代替的解剖生理功能,改良术式能将两者完好保留,显著降低术后并发症。  相似文献   
9.
We report the cytological and clinical findings of 16 fine-needle aspirates (FNAs) performed on recurrent (n = 6) and metastatic (n = 10) mixed mesodermal tumors (MMMTs). The median interval between the primary diagnosis and FNA was 16 mo. Primary sites were the endometrium (n = 11), the ovary (n = 3), the cervix (n = 1), and pelvic soft tissue (n = 1). Primary tumors showed carcinoma with homologous mesenchymal components in 13 cases and focal heterologous elements in three (two chondrosarcomas and one rhabdomyosarcoma). The FNAs showed carcinoma in all 16 cases, with adenocarcinoma differentiation in three, Mesenchymal elements were identified in aspirates of three recurrent and two metastatic lesions. They were all homologous. No heterologous mesenchymal elements were identified in the aspirates. We conclude that mesenchymal components in FNAs of MMMTs are less likely to be seen in metastatic lesions, and that heterologous mesenchymal components are rarely seen in these aspirates even in recurrent disease. These findings confirm that the epithelial component is responsible for the malignant behavior of MMMTs, and suggest that these lesions may need to be classified as sarcomatoid carcinomas rather than true carcinosarcomas. Diagn Cytopathol 1994;11:328–332. © 1994 Wiley-Liss, Inc.  相似文献   
10.
Mycoplasma arthritidis-derived mitogen (MAM) is considered to be a member of the super-antigen family despite the fact that there is no evidence until now indicating its binding to MHC class II molecules. To demonstrate its direct binding and to determine the regions involved in MHC class II and TCR interactions, we generated a recombinant wild-type and two truncated forms of the MAM protein. Data obtained in the course of the present investigation show that MAM binds specifically and significantly to human MHC class II molecules. Evidence is also provided that MAM bears two distinct binding regions: one is located within its N terminus and interacts with MHC class II molecules, while the second region which is located in its C terminus mediates its recognition by the TCR. Association of the MHC class II-associated invariant chain peptide with the peptide binding groove on the cell surface completely abolished MAM binding and presentation. This inhibitory effect is restored by the expression of HLA-DM molecules, suggesting that the nature of the peptide within the binding groove and/or the stability of the MHC class II molecules on the cell surface may modulate MAM/MHC class II interactions.  相似文献   
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