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41.
Sandra Utzschneider Fabian Becker Thomas M. Grupp Birte Sievers Alexander Paulus Oliver Gottschalk Volkmar Jansson 《Acta biomaterialia》2010,6(11):4296-4304
Poly(ether ether ketone) (PEEK) and its composites are recognized as alternative bearing materials for use in arthroplasty because of their mechanical properties. The objective of this project was to evaluate the biological response of two different kinds of carbon fiber-reinforced (CFR) PEEK compared with ultra-high molecular weight polyethylene (UHMWPE) in vivo as a standard bearing material. Wear particles of the particulate biomaterials were injected into the left knee joint of female BALB/c mice. Assessment of the synovial microcirculation using intravital fluorescence microscopy as well as histological evaluation of the synovial layer were performed 7 days after particle injection. Enhanced leukocyte–endothelial cell interactions and an increase in functional capillary density as well as histological investigations revealed that all tested biomaterials caused significantly (P < 0.05) increased inflammatory reactions compared with control animals (injected with sterile phosphate-buffered saline), without any difference between the tested biomaterials (P > 0.05). These data suggest that wear debris of CFR-PEEK is comparable with UHMWPE in its biological activity. Therefore, CFR-PEEK represents an alternative bearing material because of its superior mechanical and chemical behavior without any increased biological activity of the wear particles, compared with a standard bearing material. 相似文献
42.
川芎嗪诱导大鼠骨髓间质干细胞分化为神经元样细胞的研究 总被引:26,自引:0,他引:26
目的用川芎嗪(ligustrazin hydrochloride)在体外定向诱导SD青年鼠骨髓间质干细胞(mesenchymal stem cells,rMSCs)分化为神经元样细胞。方法用低糖DMEM冲洗骨髓腔,收集骨髓细胞悬液,接种在塑料培养瓶中。经体外扩增、纯化,选用第5代后的骨髓间质干细胞进行诱导分化。用10μg/LbFcF预诱导24h,更换成含川芎嗪的无血清培养基DMEM诱导间质干细胞分化为神经元样细胞。用免疫组织化学SABC法鉴定神经丝蛋白(NF—M)、神经元特异性烯醇化酶(NSE)、巢蛋白(nestin)、微管联合蛋白-2(MAP-2)、生长相关蛋白-43(GAP-43)、胶质纤维酸性蛋白(GFAP)的表达。结果第5代间质干细胞形态达到均一,呈梭形。用川芎嗪诱导15min到3h,间质干细胞胞体逐渐增大,并伸出细长突起形似神经元样细胞。免疫组织化学显示NF-M、NSE、nestin、MAP-2和GAP-43表达阳性,而GFAP阴性。对照组上述染色均为阴性。结论川芎嗪可诱导骨髓间质干细胞分化为神经元样细胞。 相似文献
43.
Summary A case of a 44-year-old woman with a solitary pulmonary coin lesion is presented. Histologic study of this nodule revealed a normal intraparenchymal pulmonary lymph node. A review of the literature discusses the incidence and characteristics of this entity.
Nud lymphatique intrapulmonaire: revue de la littérature. A propos d'un cas
Résumé L'observation d'un cas de lésion nodulaire du poumon est rapportée chez une femme de 44 ans. L'étude histologique du nodule a révélé un nud lymphatique intrapulmonaire normal. La revue de la littérature apprécie l'incidence et les caractéristiques de cette localisation.相似文献
44.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. 相似文献
45.
目的探讨急性脑出血患者卒中相关性肺炎(SAP)发生的危险因素,以便早期干预。方法选择急性脑出血患者196例为研究对象,其中发生SAP 82例为病例组,未发生SAP 114例为对照组。对两组的年龄、性别、心肺疾病史、GCS评分、吞咽困难、心率、血压、白细胞计数、脑出血量、鼻饲、使用胃黏膜保护剂和手术等共计23项予以比较分析。所得资料在单因素分析的基础上,又作多因素Logistic回归分析。结果急性脑出血SAP的患病率为41.837%。收缩压升高(优势比1.072,95%可信区间1.007~1.141,P=0.029)、白细胞计数增加(优势比1.331,95%可信区间1.009~1.756,P=0.043)、脑出血量增多(优势比1.079,95%可信区间1.019~1.142,P=0.010)、有心肺疾病(优势比12.275,95%可信区间1.210~124.545,P=0.034)、吞咽困难(优势比12.937,95%可信区间1.918~87.250,P=0.009)和鼻饲(优势比19.217,95%可信区间1.307~282.651,P=0.031)均促进发病。而使用胃黏膜保护剂(优势比0.157,95%可信区间0.031~0.790,P=0.025)和实施手术(优势比0.012,95%可信区间0.000~0.294,P=0.007)阻止发病。结论收缩压、白细胞计数增加、脑出血量增高、有心肺疾病、吞咽困难和鼻饲是急性脑出血发生SAP的危险因素;而使用胃黏膜保护剂和实施手术为其保护因素。 相似文献
46.
The kidneys in paroxysmal nocturnal hemoglobinuria 总被引:6,自引:0,他引:6
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder. 相似文献
47.
48.
Effects of monoclonal antibody therapy in patients with chronic lymphocytic leukemia 总被引:4,自引:0,他引:4
Foon KA; Schroff RW; Bunn PA; Mayer D; Abrams PG; Fer M; Ochs J; Bottino GC; Sherwin SA; Carlo DJ 《Blood》1984,64(5):1085-1093
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody. 相似文献
49.
本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。 相似文献
50.
带蒂腹直肌包绕阴茎增强犬尿道压力的研究 总被引:1,自引:0,他引:1
目的探讨采用带蒂腹直肌包绕球部尿道治疗男性尿失禁的可行性。方法成年雄性比格犬10条,游离阴茎周围组织,建立类似尿失禁模型。取长8.0cm,宽2.5cm全层带蒂的腹直肌。包绕球部尿道处阴茎1周。术前,术中,术后1个月、2个月分别测定尿道压力变化。结果术前平均最大尿道压力为(48.9±11.0)cm H_2O,使用带蒂腹直肌包绕阴茎后,平均最大尿道压力为(78.3±20.5)cmH_2O,与术前相比,差异有统计学意义(t=4.995,P<0.01)。术后1个月和术后2个月复查时,平均最大尿道最大压力分别为(92.2±31.6)cm H_2O和(88.3±22.4)cm H_2O,与术前相比差异均有统计学意义(t=4.011,P<0.01和t=6.058,P<0.01)。结论采用带蒂腹直肌包绕球部尿道能明显提高尿道压力,为采用此法治疗男性尿失禁提供了实验依据。 相似文献