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941.
目的:探讨我国肺血栓栓塞症(PTE)患者易栓症的发生率,以提高临床PTE的诊断与预防复发的水平。方法:自2004年2月至2009年12月,连续观察我院呼吸科、急诊呼吸监护室确诊的PTE患者123例,其中男性60例,女性63例,并对其遗传性和获得性易栓症进行回顾性分析,得出所有患者遗传性和获得性易栓症的发生率,并比较性别对抗凝蛋白缺陷的影响。结果:123例PTE患者中获得性易栓症中长期制动、静脉曲张/血栓性静脉炎及手术/创伤居前3位,其发生率分别为14.6%、12.2%及8.1%。遗传性易栓症总的发生率为:55.3%,其中发生率较高的是:蛋白S(PS)缺陷17.1%,PC缺陷10.5%,蛋白C(PC)、PS联合缺陷12.2%。抗凝蛋白缺陷男女均为34例,性别间差异无统计学意义(P0.05)。抗凝蛋白缺陷率性别间差异无统计学意义。结论:PTE患者中易栓症的发生率较高,PTE可能是遗传性和获得性易栓症共同作用的结果。  相似文献   
942.
The present study investigated the role of central metabotropic glutamate receptors (mGluRs) in interleukin-1beta (IL-1beta)-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Experiments were carried out on male Sprague-Dawley rats weighing 230 to 280 g. After administration of 0.01, 0.1, 1, or 10 pg of IL-1beta into a subcutaneous area of the vibrissa pad, we examined the withdrawal behavioral responses produced by 10 successive trials of an air-puff ramp pressure applied ipsilaterally or contralaterally to the IL-1beta injection site. Subcutaneous injection of IL-1beta produced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Intracisternal administration of CPCCOEt, a mGluR1 antagonist, or MPEP, a mGluR5 antagonist, reduced IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. Intracisternal administration of APDC, a group II mGluR agonist, or L-AP4, a group III mGluR agonist, reduced both IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia. The antiallodynic effect, induced by APDC or L-AP4, was blocked by intracisternal pretreatment with LY341495, a group II mGluR antagonist, or CPPG, a group III mGluR antagonist. These results suggest that groups I, II, and III mGluRs differentially modulated IL-1beta-induced mechanical allodynia, as well as mirror-image mechanical allodynia, in the orofacial area. PERSPECTIVE: Central group I mGluR antagonists and groups II and III mGluR agonists modulate IL-1beta-induced mechanical allodynia and mirror-image mechanical allodynia in the orofacial area. Therefore, the central application of group I mGluR antagonists or groups II and III mGluR agonists might be of therapeutic value in treating pain disorder.  相似文献   
943.
FVB and BALB/c mice show different morbidity, development of Clonorchis sinensis, and pathological changes following C. sinensis infection. FVB mice are susceptible and BALB/c mice are relatively more resistant to C. sinensis infection. To investigate the relationship between cytokine reaction and susceptibility to C. sinensis infection in FVB and BALB/c mice, we described both the patterns and kinetics of Th1 cytokines and Th2 cytokines in spleen cell culture. Interleukin (IL)-4 and IL-10 cytokine production in the culture supernatants of the concanavalin-A-stimulated spleen cells increased at 2–3 weeks post-infection in both strains. IL-5 production increased between 2 and 5 weeks post-infection in both strains, and reached a peak level at 2 weeks post-infection in BALB/c mice and 4 weeks post-infection in FVB mice. In contrast, gamma interferon (IFN-) production decreased between 2 and 4 weeks in both strains. IL-2 production increased slightly in BALB/c mice following infection, but was unchanged in FVB mice. IL-4 production over preinfection levels was significantly higher in FVB mice, whereas IFN-, IL-2, and IL-10 production were significantly higher in BALB/c mice. The levels of serum immunoglobulin E (IgE) and blood eosinophils in both mouse strains significantly increased between 3 and 6 weeks postinfection. Serum IgE levels were significantly higher in FVB mice than in BALB/c mice. The results of this study suggest that susceptibility to C. sinensis infection is associated with Th2 cytokine production, especially IL-4 which is predominant in relatively susceptible FVB mice.  相似文献   
944.
This study sought to elucidate the relationship between skeletal muscle mitochondrial dysfunction, oxidative stress, and insulin resistance in two mouse models with differential susceptibility to diet-induced obesity. We examined the time course of mitochondrial dysfunction and insulin resistance in obesity-prone C57B and obesity-resistant FVB mouse strains in response to high-fat feeding. After 5 wk, impaired insulin-mediated glucose uptake in skeletal muscle developed in both strains in the absence of any impairment in proximal insulin signaling. Impaired mitochondrial oxidative capacity preceded the development of insulin resistant glucose uptake in C57B mice in concert with increased oxidative stress in skeletal muscle. By contrast, mitochondrial uncoupling in FVB mice, which prevented oxidative stress and increased energy expenditure, did not prevent insulin resistant glucose uptake in skeletal muscle. Preventing oxidative stress in C57B mice treated systemically with an antioxidant normalized skeletal muscle mitochondrial function but failed to normalize glucose tolerance and insulin sensitivity. Furthermore, high fat-fed uncoupling protein 3 knockout mice developed increased oxidative stress that did not worsen glucose tolerance. In the evolution of diet-induced obesity and insulin resistance, initial but divergent strain-dependent mitochondrial adaptations modulate oxidative stress and energy expenditure without influencing the onset of impaired insulin-mediated glucose uptake.  相似文献   
945.
背景:目前没有关于按颈椎损伤机制分类治疗的报道,尤其是针对伸直型损伤合并后部结构复合体损伤病例,是否单纯前路就可以满足治疗需要没有详尽的阐述。文章从颈椎损伤机制方面入手进行分析。目的:观察颈前路Cage融合锁定钛板内固定治疗伸直型颈椎骨折的近期效果。方法:回顾性分析2006年6月至2011年3月在咸宁市中心医院骨科行颈椎前路椎间盘切除减压Cage植骨融合加锁定钛板内固定的伸直型颈椎骨折脱位患者15例,其中损伤与治疗节段均为单节段10例,多节段5例。对比治疗前后JOA评分与颈部功能障碍指数;根据内固定前、内固定后1周及末次随访时颈椎标准侧位X射线片,测量融合节段颈椎屈曲度及融合节段椎间高度。结果与结论:随访8-37个月,1例Cage轻度下沉、移位,所有病例无内固定断裂、松动,11例患者出现内固定后一过性咽部不适。与内固定前相比,内固定后1周、末次随访时JOA评分、颈部功能障碍指数、融合节段颈椎屈曲度及融合节段椎间高度均明显改善(P<0.05);但内固定后1周与末次随访时各项指标比较差异无显著性意义(P>0.05)。提示颈椎前路椎间盘切除减压Cage融合锁定钛板内固定治疗伸直型颈椎骨折的近期疗效良好。  相似文献   
946.
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10  000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.  相似文献   
947.
99mTc-ECD SPECT is valuable for the evaluation of cell viability and function. The purpose of the present study was to evaluate the significance of 99mTc-ECD brain SPECT in ischemic stroke. We compared 99mTc-ECD brain SPECT with perfusion and diffusion weighted images (PWI, DWI). Ten patients with acute and early subacute ischemic stroke were included in this prospective study. T2-weighted images (T2WI), DWI, PWI and 99mTc-ECD SPECT were obtained during both the acute/early subacute and late subacute stages. In the case of PWI, time to peak (TTP) and regional cerebral blood volume (rCBV) maps were obtained. The rCBV map and 99mTc-ECD SPECT images were compared in 8 lesions using DeltaAI. The asymmetry index (AI) was calculated as (Ci - Cc) X 200 / (Ci + Cc); where Ci is the mean number of pixel counts of an ipsilateral lesion and Cc is the mean number of pixel counts of the normal contralateral hemisphere. DeltaAI was defined as AIacute - AIsubacute in the ischemic core and periphery. PWI and 99mTc-ECD SPECT detected new lesions of the hyperacute stage or of evolving stroke more accurately than T2WI and DWI. 99mTc-ECD SPECT was able to localize the infarct core and peri-infarct ischemia in all lesions in both the acute and the subacute stages. DeltaAI was higher in the rCBV map than in the 99mTc-ECD SPECT images in the ischemic core (p = 0.063) and in the periphery (p = 0.091). In the 99mTc-ECD SPECT images, DeltaAI was higher in the ischemic core than in the periphery (p = 0.028). During the subacute stage, 99mTc-ECD SPECT detected all the lesions without the pseudonormalization seen in the MR images of 5/11 lesions. Based on this study, 99mTc-ECD SPECT is comparable to PWI in terms of its ability to detect acute stroke and is more useful than PWI in the case of subacute infarction.  相似文献   
948.
H2O2 enhances Ca2+ release from osteoblast internal stores   总被引:3,自引:0,他引:3  
The physiological activity of osteoblasts is known to be closely related to increased intracellular Ca2+ activity ([Ca2+]i) in osteoblasts. The cellular regulation of [Ca2+]i in osteoblasts is mediated by Ca2+ movements associated with Ca2+ release from intracellular Ca2+ stores, and transmembrane Ca2+ influx via Na+-Ca2+ exchanger, and Ca2+ ATPase. Reactive oxygen species, such as H2O2, play an important role in the regulation of cellular functions, and act as signaling molecules or toxins in cells. In this study, we investigated the effects of H2O2 on cellular Ca2+ regulation in osteoblasts by measuring intracellular Ca2+ activities using cellular calcium imaging techniques. Osteoblasts were isolated from the femurs and tibias of neonatal rats, and cultured for 7 days. The cultured osteoblasts were loaded with a Ca2+-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored using a cooled CCD camera, and subsequently analyzed using image analyzing software. The results obtained are as follows: (1) The osteoblasts with lower basal Ca2+ activities yielded a transient Ca2+ increase, a Ca2+ spike, while osteoblasts with higher basal Ca2+ activities showed a continuous increase in [Ca2+]i leading to cell death. (2) Ca2+ spikes, generated after removing Na+ from superfusing solutions, were blocked by H2O2 and this was followed by a sustained increase in Ca2+ activity. (3) ATP- induced Ca2+ spikes were inhibited by pretreating with H2O2 and this was followed by a continuous increase of [Ca2+]i. When cells were pretreated with the exogenous nitric oxide (NO) donor S-Nitroso-N-acetylpenicilance (SNAP, 50 microM), treatments of ATP (1 mM) induced a Ca2+ spike-like increase, but [Ca2+]i did not return to the basal level. (4) The expression of inositol- 1,4,5-triphosphate receptor (IP3R) was enhanced by H2O2. Our results suggest that H2O2 modulates intracellular Ca2+ activity in osteoblasts by increasing Ca2+ release from the intracellular Ca2+ stores.  相似文献   
949.
Qin X  Xu M  Zhang Y  Li J  Xu X  Wang X  Xu X  Huo Y 《Atherosclerosis》2012,222(2):307-313
ObjectivesWe conducted a meta-analysis of relevant randomized trials to assess whether folic acid supplementation reduces the progression of atherosclerosis as measured by carotid intima-media thickness (CIMT).MethodsThis analysis included 2052 subjects from ten folic acid randomized trials with the change in CIMT reported as one of the end points. Summary estimates of weighted mean differences (WMDs) and 95% CIs were obtained by using random-effect models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity.ResultsOur analysis showed that folic acid supplementation significantly reduces the progression of CIMT (WMD: ?0.04 mm; 95%CI: ?0.07, ?0.02; P < 0.001), particularly in subjects with chronic kidney disease (CKD) (WMD: ?0.16 mm; 95%CI: ?0.26, ?0.07; P = 0.0006) or high cardiovascular disease (CVD) risk (WMD: ?0.05 mm; 95%CI: ?0.11, 0.00; P = 0.06) but not in subjects who were generally healthy with only elevated homocysteine concentrations (WMD:0.00 mm; 95%CI: ?0.01, 0.01; P = 0.35). Furthermore, meta-regression analysis of the data showed that the baseline CIMT levels (P = 0.011) and the percent reduction of homocysteine (P < 0.001) were positively related to the effect size. Consistently, a greater beneficial effect was seen in those trials with baseline CIMT levels ≥0.8 mm (WMD: ?0.14 mm; 95%CI: ?0.19, ?0.08; P < 0.0001), and a reduction in the homocysteine concentration ≥30% (WMD: ?0.22 mm; 95%CI: ?0.38, ?0.06; P = 0.009). In the corresponding comparison groups, the effect sizes were attenuated and insignificant.ConclusionsOur findings indicate that folic acid supplementation is effective in reducing the progression of CIMT, particularly in subjects with CKD or high CVD risk and among trials with higher baseline CIMT levels or a larger homocysteine reduction.  相似文献   
950.

Background

Prone positioning for acute respiratory distress syndrome (ARDS) has no impact on mortality despite significant improvements in oxygenation. However, a recent trial demonstrated reduced mortality rates in the prone position for severe ARDS. We evaluated effects of prone position duration and protective lung strategies on mortality rates in ARDS.

Methods

We extensively searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials (RCTs) reporting on prone positioning during acute respiratory failure in adults for inclusion in our meta-analysis.

Results

Eight trials met our inclusion criteria, Totals of 1,099 and 1,042 patients were randomized to the prone and supine ventilation positions. The mortality rates associated with the prone and supine positions were 41% and 47% [risk ratio (RR), 0.90; 95% confidence interval (CI), 0.82-0.98, P=0.02], but the heterogeneity was moderate (P=0.01, I2=61%). In a subgroup analysis, the mortality rates for lung protective ventilation (RR 0.73, 95% CI, 0.62-0.86, P=0.0002) and duration of prone positioning >12 h (RR 0.75, 95% CI, 0.65-0.87, P<0.0001) were reduced in the prone position. Prone positioning was not associated with an increased incidence of cardiac events (RR 1.01, 95% CI, 0.87-1.17) or ventilator associated pneumonia (RR 0.88, 95% CI, 0.71-1.09), but it was associated with an increased incidence of pressure sores (RR 1.23, 95% CI, 1.07-1.41) and endotracheal dislocation (RR 1.33, 95% CI, 1.02-1.74).

Conclusions

Prone positioning tends to reduce the mortality rates in ARDS patients, especially when used in conjunction with a lung protective strategy and longer prone position durations. Prone positioning for ARDS patients should be prioritized over other invasive procedures because related life-threatening complications are rare. However, further additional randomized controlled design to study are required for confirm benefit of prone position in ARDS.  相似文献   
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