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The role of the supplementary interaction between virion-bound host ICAM-1 and LFA-1 on target cells in sensitivity to neutralization of human immunodeficiency virus type 1 (HIV-1) is poorly studied. Serum samples from four long-term nonprogressors (LTNPs) and sequential sera from one progressor were used to assess neutralization sensitivity of isogenic ICAM-1-negative and ICAM-1-bearing HIV-1(NL4-3), a prototype of T-cell-line-adapted viruses. We found that virus neutralization sensitivity to the studied sera is not modified by the additional interaction between virally embedded ICAM-1 and LFA-1 under an inactive state. However, expression on the target cell surface of an activated LFA-1 form renders ICAM-1-bearing virus particles, but not viruses devoid of ICAM-1, more refractory to neutralization by sera from three out of four LTNPs and all sequential sera from the person who has experienced a progression of the HIV-1-associated disease. Although no conclusive correlation could be drawn between virus susceptibility to neutralization and the disease status or stages of HIV-1 infection, these findings demonstrate that other nonspecific virus-cell interactions mediated by virion-anchored host proteins and their normal cognate ligands on target cells represent factors that can affect the mechanism of HIV-1 neutralization.  相似文献   
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Using two mAb, one specific to the alternative exon 6-dependentepitope of CD45 molecules(JH6.2) and one a natural thymocytotoxicautoantibody (NTA) with an unknown reactive epitope (NTA260),we subdivided splenic CD4+ T cells from 2-month-old BALB/c miceinto five phenotypically distinct subsets. CD45RC+NTA260(SI) cells were phenotypically analogous to CD4+ T cells predominatingin newborn mice and produced a significant amount of IL-2, butnot so IL-4, IL-10 or IFN-RC="http://intimm.oxfordjournals.org/math/gamma.gif" ALT="{gamma}" BORDER="0"> when stimulated with immobilizedanti-CD3 mAb in vitro. They appeared to consist mainly of naiveThP cells. The CD45RC+;NTA260+ (S II) subset also produced IL-2,but not other cytokines; however, the IL-2 levels produced weremuch higher than seen with the S I subset, thereby suggestingthe predominance of further maturated ThP cells. The D45RCNTA260+(S III) subset mainly produced IL-4, IL-10, IFN-RC="http://intimm.oxfordjournals.org/math/gamma.gif" ALT="{gamma}" BORDER="0"> and less IL-2,and contained memory cells that helped the secondary antibodyresponse to a recall antigen, and hence contained Th2 and probablya mixture of Th0 and Th1 cells. The CD45RCNTA260(S IV) subset was a poor responder to the immobilized anti-CD3mAb. The CD45RCbrightNTA260dull(S V) subset consisted of a smallnumber of cells that were phenotypically analogous to activatedCD4+ T cells. While an age-associated decrease in the proportionof S I and less markedly in S II and in turn increase in S IIIsubsets of CD4+ T cells occurred in normal BALB/c mice, autoimmunedisease-prone (NZBxNZW)F1 mice showed a marked age-associateddecrease in the proportion of not only S I, II but also IIIsubsets. As aged (NZBxNZW)F1 mice carry CD4+ T helper cellsfor IgG anti-DNA antibody production, such age-associated polarizationto the S IV subset appears to be critical in the pathogeneslsof autoimmune disease in these mice.  相似文献   
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目的研究大花红景天(Rhod iola Crenu lata,RC)对苯血液毒性的干预作用。方法用1 600 mg/kg苯对100只成年雌性大鼠灌胃3周复制出苯血液毒性的动物模型后,按白细胞数分为模型对照组,13.5 mg/kg鲨肝醇组,1 000、2 000、4 000 mg/kg RC组进行治疗,每周5 d,连续5周,另设不做处理的正常对照组,每组10只。实验结束时,测定血细胞、骨髓象、骨髓细胞超微结构、骨髓嗜多染红细胞微核率、血清超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量。结果RC治疗苯中毒大鼠5周后,RC可恢复苯引起的白细胞减少,降低骨髓嗜多染红细胞微核率,提高骨髓红细胞系水平(P<0.01),2 000 mg/kg RC组可促进苯中毒大鼠骨髓粒细胞系增生(P<0.01)。但RC对血清SOD活力和MDA含量并无影响。结论RC对苯中毒引起的白细胞下降有一定的治疗作用,但效果并不明显。  相似文献   
5.
《Injury》2016,47(12):2733-2738
IntroductionPoor bone quality and unstable fractures increase the cut-out rate in implants with gliding lag screws. The U-Blade (RC) lag screw for the Gamma3® nail was introduced to provide monoaxial rotational stability of the femoral head and neck fragment. The purpose of this study was to evaluate whether the use of the U-Blade (RC) lag screw is associated with reduced cut-out in patients with OTA/AO 31A1-3 fractures.Material & methodsBetween 2009 and 2014, 751 patients with OTA/AO 31A1-3 fractures were treated with a Gamma3® nail at our institution. Out of this sample 199 patients were treated with U-blade (RC) lag screws. A total of 135 patients (117 female, 18 male) with standard lag screw (treatment group A) were matched equally regarding age (±4 years) sex, fracture type and location to 135 patients with U-blade (RC) lag screw (treatment group B). Within a mean follow up of 9.2 months (range 6–18 months) we assessed the cut-out rate, the calTAD, lag screw migration, the Parker's mobility score and the Parker’s ratio at postoperatively, six and 12 months following surgery. Furthermore we recorded all complications, ASA-Score, hospital stay and duration of surgery retrospectively.ResultsThe most common fracture among group B with a cut-out of the lag screw were AO/OTA 2.3 and 3.2 fractures whereas in group A cut-out was most commonly seen in AO/OTA 2.1, 2.2 and 2.3 fractures, there was no significant reduction of the cut-out rate in group B 2.2% (n = 3) compared to group A 3.7% (n = 5). The duration of surgery was significantly shorter in group A (p < 0.05). There was no significant difference in lag screw placement, the Parker’s ratio and mobilization.ConclusionIn our study the U-Blade (RC) lag screw did not reduce the cut-out in treatment of OTA/AO 31A1-3 fractures at all. Considering the longer duration of surgery and the higher costs of the U-Blade (RC) lag screw, our results do not justify its use. However, further prospective randomized studies will be necessary.  相似文献   
6.
目的 研究小骨窗开颅术与大骨瓣开颅术对高血压脑出血的治疗效果.方法 对2007至2011年间收治的80例高血压脑出血患者随机分为实验组和对照组各40例,实验组使用小骨窗开颅术,对照组使用大骨瓣开颅血肿清除术进行治疗,对两组患者治疗效果及并发症情况进行观察和比较.结果 对照组患者痊愈3例,显著改善22例,有效率62.5%;实验组痊愈5例,显著改善30例,有效率87.5%,实验组显著高于对照组(P<0.05).实验组患者肺部感染发生率30%,显著低于对照组的52.5%(P< 0.05),其余并发症两组比较差异无显著性(P>0.05).结论小骨窗开颅术比大骨瓣开颅血肿清除术有更好的治疗效果而操作更简便,术后并发症更少,是一种理想的手术方案.  相似文献   
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ObjectivesThe aim of this study was to assess the safety and effectiveness of directional atherectomy (DA) for endovascular treatment of peripheral arterial disease (PAD) in infrainguinal arteries in patients with claudication or critical limb ischemia.BackgroundTo date, no prospective, multicenter, independently-adjudicated study has evaluated the effectiveness and durability of DA in the treatment of PAD. Previous DA studies have not been prospectively powered to evaluate any differences in outcomes in patients with and without diabetes.MethodsDEFINITIVE LE (Determination of EFfectiveness of the SilverHawk® PerIpheral Plaque ExcisioN System (SIlverHawk Device) for the Treatment of Infrainguinal VEssels / Lower Extremities) prospectively enrolled subjects at 47 multinational centers with an infrainguinal lesion length up to 20 cm. Primary endpoints were defined as primary patency at 12 months for claudicants and freedom from major unplanned amputation for critical limb ischemia (CLI) subjects. A pre-specified statistical hypothesis evaluated noninferiority of primary patency in diabetic versus nondiabetic claudicants. Independent angiographic and sonographic core laboratories assessed outcomes, and events were adjudicated by a clinical events committee.ResultsA total of 800 subjects were enrolled. The 12-month primary patency was 78% (95% confidence interval: 74.0% to 80.6%) in claudicants, with a 77% rate in the diabetic subgroup versus 78% in the nondiabetic subgroup (noninferior, p < 0.001). The rate of freedom from major unplanned amputation of the target limb at 12 months in CLI subjects was 95% (95% confidence interval: 90.7% to 97.4%). Periprocedural adverse events included embolization (3.8%), perforation (5.3%), and abrupt closure (2.0%). The bail-out stent rate was 3.2%.ConclusionsThe DEFINITIVE LE study demonstrated that DA is a safe and effective treatment modality at 12 months for a diverse patient population with either claudication or CLI. Furthermore, DA was shown to be noninferior for treating PAD in patients with diabetes compared with those without diabetes. (Study of SilverHawk/TurboHawk in Lower Extremity Vessels [DEFINITIVE LE]; NCT00883246).  相似文献   
9.
The radical cystectomy (RC) for muscle-invasive bladder cancer is one of the most morbid and complex urologic procedures performed today. To avoid these complications, the partial cystectomy (PC) has been offered as an alternative in carefully selected patients as a means of achieving equal oncologic efficacy with less morbidity. Selection criteria should include solitary tumors without concomitant carcinoma in situ (CIS) and amenable to resection with 1–2 cm margins in a normally functioning bladder. In addition to the standard work-up, random bladder and prostatic biopsies may be performed. The PC can be performed through an open, laparoscopic, or robot-assisted approach, each with acceptable outcomes. A number of techniques have been developed to identify and resect the tumor completely with negative margins, while preventing tumor spillage within the abdomen. While there are no randomized trials, single institution series have demonstrated acceptable oncologic outcomes in appropriately selected patients. Therefore, offering PC in the appropriate candidate, including those patients who do not accept or are unfit for the associated morbidity of a RC, represents an acceptable alternative.  相似文献   
10.
In this study, the generalized softened variable angle truss-model (GSVATM) is used to predict the response of reinforced concrete (RC) beams under torsion at the early loading stages, namely the transition from the uncracked to the cracked stage. Being a 3-dimensional smeared truss model, the GSVATM must incorporate smeared constitutive laws for the materials, namely for the tensile concrete. Different smeared constitutive laws for tensile concrete can be found in the literature, which could lead to different predictions for the torsional response of RC beams at the earlier stages. Hence, the GSVATM is used to check several smeared constitutive laws for tensile concrete proposed in previous studies. The studied parameters are the cracking torque and the corresponding twist. The predictions of these parameters from the GSVATM are compared with the experimental results from several reported tests on RC beams under torsion. From the obtained results and the performed comparative analyses, one of the checked smeared constitutive laws for tensile concrete was found to lead to good predictions for the cracking torque of the RC beams regardless of the cross-section type (plain or hollow). Such a result could be useful to help with choosing the best constitutive laws to be incorporated into the smeared truss models to predict the response of RC beams under torsion.  相似文献   
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