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91.
Few human CD8(+) T-cell epitopes in mycobacterial antigens have been described to date. Here we have identified a novel HLA-B*35-restricted CD8(+) T-cell epitope in Mycobacterium tuberculosis Rv2903c based on a reverse immunogenetics approach. Peptide-specific CD8 T cells were able to kill M. tuberculosis-infected macrophages and produce gamma interferon and tumor necrosis factor alpha.  相似文献   
92.
Thirty-four subjects meeting diagnostic criteria for episodic tension-type headache and 42 who rarely experienced headaches participated in two laboratory sessions in which cephalic electromyographic (EMG) activity, electrodermal activity, heart rate, and finger temperature were recorded. Subjects performed relaxation, choice reaction time, psychomotor tracking, voluntary muscle contraction, and cold pressor tasks. Headache subjects showed significantly greater EMG activity than controls during baseline and stressful task performance. During relaxation, both groups reduced EMG activity from baseline levels, and there was no significant difference in EMG level between the groups during relaxation. Headache subjects reported higher levels of subjective anxiety, depression, anger, and stress than controls. Headache subjects also reported higher levels of pain than controls, and headache subjects reported greater pain during stressful task performance relative to baseline and recovery periods.This research was supported by NIH Grant R01-NS-25114.  相似文献   
93.
Spontaneous activity and receptive field size for spinal wide dynamic range (WDR) neurons were measured and related to the mechanical allodynia in both neuropathic (L5-L6 ligation, 14 days post-injury) and complete Freund's adjuvant-inflamed rats (CFA, 2 days post-injury). The size of the WDR receptive field located on the hindpaw expanded significantly (p<0.01) following both modes of injury, with no difference between CFA and neuropathic animals. Likewise, the spontaneous firing of WDR neurons was significantly elevated following both the CFA (4.4+/-0.6 spikes/s, p<0.01) and neuropathic (3.2+/-0.3 spikes/s, p<0.05) injuries compared to naive (2.1+/-0.2 spikes/s) and sham-neuropathic (1.9+/-0.3 spikes/s) rats. Furthermore, the spontaneous WDR activity recorded from CFA rats was also significantly greater (p<0.05) than neuropathic rats. Mechanical allodynia, as measured by application of a von Frey hair stimulus, was observed from both CFA and neuropathic rats, however, the degree of sensitivity was significantly greater (p<0.01) for the CFA animals. These data suggest that the differences in mechanical sensitivity between CFA and neuropathic rats may be related to their respective changes in WDR spontaneous activity, but not to the changes in receptive field size, and is further demonstration of the importance of spontaneous WDR activity in determining mechanical sensitivity following injury.  相似文献   
94.
皮肤穿支血管的解剖学研究   总被引:18,自引:6,他引:18  
目的:对全身皮肤血管区域进行定性和定量分析,确定全身皮肤穿支血管的位置、数量、口径、穿支蒂的长度、类型、来源血管以及穿支所供应皮肤的面积,为穿支皮瓣提供血管解剖基础。方法:选用10具新鲜尸体,采用改良氧化铅一明胶灌注技术进行动脉灌注。将每个口径大于0.5mm的穿支血管进行解剖并记录。拍摄X线片以显示皮肤内血管的形态和分布。定量数据分析包括全身各部位的穿支血管的数量、口径、类型及其供应区域的面积。结果:发现全身128支起源血管发出440支穿支供应皮肤。其中肌皮穿支与肌间隔穿支之比为3:2。穿支平均直径为0.7mm。穿支血管的分布规律如下:①躯干皮肤的血供主要来自肌皮穿支,这些穿支在皮肤内的走行距离和分布范围大于肢体皮肤的穿支。②肢体皮肤的血供主要来自肌间隙穿支血管,主要分布在深筋膜表面,皮神经和浅静脉周围穿支之间形成链式血管吻合。③单位面积的穿支数量与皮肤的移动程度成反比,穿支的口径大小和穿支在皮肤内走行距离与皮肤移动度成正比,与穿支的供应面积成正比。结论:本研究提供详细的皮肤穿支血管解剖数据,为临床设计应用穿支皮瓣提供解剖学依据。  相似文献   
95.
96.
This study was designed to examine whether anxious personality, i.e. trait anxiety, influences the autonomic nervous functions in humans without manipulation of experimental stressors. The degrees of state and trait anxiety, blood pressure, heart rate, pupillary light reflex (PLR), and body temperature were measured at the same hour on four different days in 14 healthy college students. A multiple regression analysis showed that trait anxiety predominantly influenced state anxiety and the PLR parameters. A single regression analysis showed that trait anxiety positively correlated to the initial pupillary diameter and the constricted diameter of PLR and negatively to the amplitude of PLR. It was concluded that trait anxiety predicts state anxiety and a smaller amplitude of PLR in humans at rest.  相似文献   
97.
98.
Handedness is a basic property of spirals. In many cases it is possible to determine whether spiral fractures are right or left handed by analysis of radiographs. Spiral fractures of the tibia show striking bilateral symmetry, with right-handed spirals predominating on the left side of the body, and left-handed spirals on the right.  相似文献   
99.
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells.  相似文献   
100.
AimRates of simultaneous liver and kidney transplantation (SLKT) have increased, but indications for SLKT remain poorly defined. Additional data are needed to determine which patients benefit from SLKT to best direct use of scarce donor kidneys.MethodsData were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) database for all SLKT performed until the end of 2017. Patients were divided by pretransplant dialysis status into no dialysis before SLKT (preemptive kidney transplant) and any dialysis before SLKT (nonpreemptive). Baseline characteristics and outcomes were compared.ResultsBetween 1989 and 2017, inclusive, 84 SLKT procedures were performed in Australia, of which 24% were preemptive. Preemptive and nonpreemptive SLKT recipients did not significantly differ in age (P = .267), sex (P = .526), or ethnicity (P = .870). Over a median follow-up time of 4.5 years, preemptively transplanted patients had a statistically equivalent risk of kidney graft failure (hazard ratio (HR) 1.83, 95% confidence interval [CI]: 0.36-12.86, P = .474) and all-cause mortality (HR 1.69, 95% CI: 0.51-5.6, P = .226) compared to nonpreemptive patients. Overall, 1- and 5-year survival rates for all SLKTs were 92% (95% CI: 86-96) and 60% (95% CI: 45-75), respectively.ConclusionKidney graft and overall patient survival were similar between patients with preemptive kidney transplant and those who were dialysis dependent.  相似文献   
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