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51.
Human platelet membrane glycoproteins IIb and IIIa (GPIIb and IIIa) were incorporated into phospholipid vesicles by the reverse-phase technique to assess the ability of GPIIb and IIIa to function as a Ca2+ channel. Movement of Ca2+ across the lipid bilayer was quantitated by injection of proteoliposomes with encapsulated Fura-2 into Ca2+ buffers and measurement of Fura-2 fluorescence as an indicator of Ca2+ influx. Reciprocally, to assess the function of proteins in an inside-out orientation, Ca2+-loaded vesicles were injected into Ca2+-free buffer and Ca2+ efflux monitored by a calcium electrode. Incorporation of the IIb-IIIa complex produced significant facilitation of Ca2+ movement across the lipid bilayer. No net transmembrane Ca2+ movement was seen with dissociated IIb and IIIa. Movement of Ca2+ was proportional to the transmembrane Ca2+ gradient. Ca2+ movement into the vesicles was inversely proportional to extravesicular NaCl from 25 to 150 mmol/L, analogous to several studies in the intact platelet. Adenosine triphosphate had no effect on Ca2+ movement into or out of the vesicles. Specific inhibition of a Ca2+ shift into the vesicles was seen with M148, a monoclonal antibody to IIb/IIIa, while no inhibition was observed with a panel of other anti-IIb/IIIa monoclonal antibodies. This suggests that a specific site on the complex or orientation of the complex is essential for calcium channel function. These data demonstrate that the GPIIb/IIIa complex can serve as a passive Ca2+ channel across a phospholipid bilayer and has the potential to play a role in Ca2+ flux across the platelet plasma membrane. 相似文献
52.
目的 对比分析单纯后路内固定+一期经腰椎间孔病椎间病灶清除(TLIF)与经典的前后联合手术在布氏杆菌性脊柱炎患者中的临床疗效及安全性。 方法 对我院2015年1月至2017年12月收治的93例布病性脊柱炎患者的临床资料进行分析。按手术方式分为观察组(45例)和对照组(48例)。对两组患者的基础数据、临床指标、术前术后各项指标水平以及术后并发症、植骨治愈情况。 结果 观察组与对照组基础数据比较,差异无统计学意义(P>0.05)。观察组患者的手术时间、住院天数、术中出血量及术后下床时间均明显低于对照组(P<0.01)。两组患者术后3个月的ODI、VAS、CRP、ESR及Cobb角均明显低于术前(P<0.05);术后3个月,观察组患者的ODI、VAS、CRP、ESR及Cobb角均明显低于对照组(P<0.05)。观察组术后并发症发生率(4.4%)明显低于对照组(25.0%)(Χ2=7.674,P<0.01)。 结论 TLIF治疗布氏杆菌性脊柱炎患者的临床疗效突出,安全性较好,更有利于患者术后身体的恢复。 相似文献
53.
MA Suckow SL Voytik-Harbin LA Terril SF Badylak 《Journal of investigative surgery》2013,26(5):277-287
Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material. 相似文献
54.
Simone M. De LA Rie Eric F. Van furth Annemieke De Koning Greta Noordenbos Marianne C. H. Donker 《Eating disorders》2013,21(4):345-351
Having a relative with an eating disorder (ED) affects the life of family caregivers and may thus affect their quality of life. To study this aspect, 40 caregivers of ED patients filled out a health-related quality of life questionnaire (Short Form-36) and a questionnaire on the impact of the ED on various areas of life domains, and on the relationship with the ED patient and the need for professional support. Quality of life of caregivers was worse than in a normal reference group. Specifically, mental health, vitality and emotional role functioning were reported to be most impaired. ED appeared to affect families’ lives substantially. In response to the ED, caregivers felt anxious, powerless, sad, or desperate. The relationship of the caregiver with the ED patient had also changed. Caregivers were more worried, lost their trust, and reported more conflicts. Seventy five percent welcomed professional support. Caregivers need practical advice, information on ED, and emotional support. Quality of life of caregivers should be addressed in the treatment of ED. 相似文献
55.
Paul Cumming Guoming Xiong Christian LA Fougère Axel Rominger Peter Bartenstein Hans‐Georg Buchholz Markus Piel Frank Rösch Gerhard Gründer Ingo Vernaleken 《Synapse (New York, N.Y.)》2013,67(4):199-203
Positron emission tomography (PET) with the high affinity dopamine D2/3 receptor ligand [18F]‐fallypride affords estimates of the binding potential (BPND) in extra‐striatal regions of low receptor abundance, but the sufficient recording time for accurate measurements in striatum has been called into question. We have earlier argued that transient equilibrium measurements are obtained in striatum with [18F]‐fallypride PET recordings of 3 h duration, which may be the practical limit for clinical investigations without interrupted scanning. However, the high extraction fraction of [18F]‐fallypride predicts flow‐dependence of tracer delivery to brain, which may be a source of variance of the apparent BPND in regions of high binding. To test this prediction, we conducted a retrospective analysis of [18F]‐fallypride PET data from a group of 50 healthy volunteers (age 18–58 years [mean ± SD: 32.6 ± 10.6), who had participated in clinical studies without arterial input measurements. We used the initial 120‐s integral (AUC) of the venous confluence (VC) as a surrogate marker for cerebral blood flow (CBF) and tested for correlations between regional estimates of BPND calculated by the simplified reference tissue model (SRTM) and the individual VC‐AUC. The magnitude of BPND in a high binding region (putamen), but not in a low binding region (thalamus) correlated positively with VC‐AUC, suggesting that approximately 9% of the variance in the [18F]‐fallypride BPND in putamen can be attributed to individual differences in this surrogate marker for CBF, a contribution equal in magnitude to the effects of age on BPND in putamen of the present healthy control group. Synapse, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
56.
目的通过观察亚麻子水提液对二肽基肽酶-4(DPP-4)、α-葡萄糖苷酶抑制作用,为该药防治糖尿病提供实验依据。方法①以DPP-4酶、缓冲液、底物建立DPP-4抑制剂的体外筛选体系,对亚麻子水提液进行抑制实验,采用发色底物法测定吸光度(OD),计算DPP-4抑制率及IC50值;②以蔗糖为底物建立α-葡萄糖苷酶活性抑制模型,采用葡萄糖氧化酶法测定亚麻子水提液对α-葡萄糖苷酶的抑制作用,计算其抑制率和IC50值。结果①亚麻子具有轻度DPP-4抑制作用,其IC50值738.20mg/L;②亚麻子具有α-葡萄糖苷酶抑制作用,其IC50值为365.9mg/mL。结论亚麻子水提液可一定程度地抑制DPP-4及α-葡萄糖苷酶活性。 相似文献
57.
目的了解广州市荔湾区青少年脊柱侧凸的患病率。方法 2011年7月~2012年1月对荔湾区8351名7~15岁在校中小学生进行了脊柱侧凸普查,应用脊柱侧凸两检法(体检、X线照片),体检阳性或可疑阳性者到医院照脊柱全长正侧位X片,采用Cobb法测量,Cobb角≥10°诊断为脊柱侧凸。结果一检阳性结果 175名(2.1%),二检阳性为85名(1.02%),男性31名,女性54名,男∶女患病率比为1∶1.76,其中特发性脊柱侧凸81名,占95.3%,先天性侧凸3名,神经肌肉源性1名。结论荔湾区中小学生脊柱侧凸发病率为1.02%,通过普查,可以早发现、早诊断青少年脊柱侧凸,及时选择适当方法进行治疗。 相似文献
58.
von Willebrand factor released from Weibel-Palade bodies binds more avidly to extracellular matrix than that secreted constitutively 总被引:8,自引:5,他引:8
Large multimers of von Willebrand factor (vWf) are released from the Weibel-Palade bodies of cultured endothelial cells following treatment with a secretagogue (Sporn et al, Cell 46:185, 1986). These multimers were shown by immunofluorescent staining to bind more extensively to the extracellular matrix of human foreskin fibroblasts than constitutively secreted vWf, which is composed predominantly of dimeric molecules. Increased binding of A23187-released vWf was not due to another component present in the releasate, since releasate from which vWf was adsorbed, when added together with constitutively secreted vWf, did not promote binding. When iodinated plasma vWf was overlaid onto the fibroblasts, the large forms bound preferentially to the matrix. These results indicated that the enhanced binding of the vWf released from the Weibel-Palade bodies was likely due to its large multimeric size. It appears that multivalency is an important component of vWf interaction with the extracellular matrix, just as has been shown for vWf interaction with platelets. The pool of vWf contained within the Weibel-Palade bodies, therefore, is not only especially suited for platelet binding, but also for interaction with the extracellular matrix. 相似文献
59.
Hematopoietic defects in mice lacking the sialomucin CD34 总被引:9,自引:5,他引:9
Cheng J; Baumhueter S; Cacalano G; Carver-Moore K; Thibodeaux H; Thomas R; Broxmeyer HE; Cooper S; Hague N; Moore M; Lasky LA 《Blood》1996,87(2):479-490
Although the pluripotent hematopoietic stem cell can only be definitively identified by its ability to reconstitute the various mature blood lineages, a diversity of cell surface antigens have also been specifically recognized on this subset of hematopoietic progenitors. One such stem cell-associated antigen is the sialomucin CD34, a highly O-glycosylated cell surface glycoprotein that has also been shown to be expressed on all vascular endothelial cells throughout murine embryogenesis as well as in the adult. The functional significance of CD34 expression on hematopoietic progenitor cells and developing blood vessels is unknown. To analyze the involvement of CD34 in hematopoiesis, we have produced both embryonic stem (ES) cells and mice that are null for the expression of this mucin. Analysis of yolk saclike hematopoietic development in embryoid bodies derived from CD34- null ES cells showed a significant delay in both erythroid and myeloid differentiation that could be reversed by transfection of the mutant ES cells with CD34 constructs expressing either a complete or truncated cytoplasmic domain. Measurements of colony-forming activity of hematopoietic progenitor cells derived from yolk sacs or fetal livers isolated from CD34-null embryos also showed a decreased number of these precursor cells. In spite of these diminished embryonic hematopoietic progenitor numbers, the CD34-null mice developed normally, and the hematopoietic profile of adult blood appeared typical. However, the colony-forming activity of hematopoietic progenitors derived from both bone marrow and spleen is significantly reduced in adult CD34-deficient animals, and these CD34-deficient progenitors also appear to be unable to expand in liquid cultures in response to hematopoietic growth factors. Even with these apparent progenitor cell deficiencies, CD34- null animals showed kinetics of erythroid, myeloid, and platelet recovery after sublethal irradiation that are indistinguishable from wild-type mice. These data strongly suggest that CD34 plays an important role in the formation of progenitor cells during both embryonic and adult hematopoiesis. However, the hematopoietic sites of adult CD34-deficient mice may still have a significant reservoir of progenitor cells that allows for normal recovery after nonmyeloablative peripheral cell depletion. 相似文献
60.
二氧化碳气腹对肿瘤细胞生长和播散影响的研究 总被引:4,自引:0,他引:4
目的 研究静脉使用 5 %NaHCO3 纠正CO2 气腹造成的酸中毒能否改善其对肿瘤细胞的促生长和播散作用。方法 观察静脉推注 5 %NaHCO3 的CO2 气腹组、CO2 气腹组及对照组带瘤Wister大鼠的肿瘤生长及穿刺点转移情况。结果 静脉推注 5 %NaHCO3 的CO2 气腹组、CO2 气腹组及对照组肿瘤的重量、体积和腹水体积有差异 ,但无统计学意义。穿刺点转移率无明显差异。结论 CO2 气腹影响肿瘤细胞生长和播散的机制复杂 ,不能完全以CO2 引起机体酸中毒解释。未找到通过静脉推注 5 %NaHCO3 可改善CO2 气腹对肿瘤细胞生长影响的基础理论依据。 相似文献