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61.
目的:心肌梗死所致的细胞缺失和瘢痕形成是心力衰竭乃至死亡的病理基础,目前药物治疗、介入治疗和外科手术均不能替代坏死心肌和彻底改善心脏功能。观察骨髓干细胞移植对心肌梗死大鼠血流动力学指标和心功能的影响。方法:实验于2005-03/2006-10在哈尔滨医科大学附属第一医院细胞移植中心完成。①实验动物:SD雄性大鼠60只作为细胞移植的受体,随机数字表法分成假手术组、心肌梗死组、细胞移植组,20只/组。另取SD雄性幼鼠10只作为骨髓干细胞的供体。实验过程中对动物的处置符合动物伦理学标准。②实验方法:取幼鼠股骨骨髓,Percoll分离后收取细胞层,加入含体积分数为0.1的胎牛血清、100IU/mL青霉素、100g/mL链霉素的DMEM营养液,差速贴壁法分离骨髓干细胞,达80%~90%融合时采用胰酶 乙二胺四乙酸消化传代。向含有第3代骨髓干细胞的培养液中加入5-氮杂胞嘧啶核苷进行诱导,3周后行BrdU标记,离心后配制成1×1012L-1的细胞悬液用于移植。心肌梗死组、细胞移植组大鼠建立心肌梗死模型,假手术组未结扎冠状动脉。细胞移植组吸取0.2mL骨髓干细胞悬液注射到瘢痕组织中,心肌梗死组注入等量干细胞培养液基质,假手术组不予任何移植处理。③实验评估:术后4周,利用导管和心动超声技术检测各组大鼠左室舒张末期内压、左室收缩末期内压、左室压力最大变化值、左室压力最小变化值、等容时间常数和心率。结果:术后4周,与假手术组比较,心肌梗死组左室收缩末期内压、左室压力最大变化值、左室压力最小变化值均明显降低(P<0.01),左室舒张末期内压、等容时间常数均明显增高(P<0.01);与心肌梗死组比较,细胞移植组以上各项指标均明显好转(P<0.01)。结论:骨髓干细胞移植到瘢痕心肌组织中,能改善心肌梗死后大鼠的血流动力学参数和心脏功能。  相似文献   
62.
To determine the prevalence of small lung nodules on low‐dose helical computed tomography (CT) in a Western Australian cohort of asymptomatic long‐term cigarette smokers and to compare this with a large, similarly derived cohort of North Americans from the Mayo Clinic Lung Cancer Screening Trial. Forty‐nine asymptomatic long‐term cigarette smokers of minimum age 50 years underwent a low‐dose 64‐slice helical CT of the lungs. Images were viewed on a soft copy reporting station with thin section axial and coronal images, maximum intensity projection images, and advanced image manipulation tools. The prevalence of all nodules was 39%, significantly lower than the Mayo Clinic cohort prevalence of 51% (P < 0.01, Fisher's exact test), despite the use of more advanced imaging technology and image manipulation designed to increase the sensitivity for nodules. The prevalence of small nodules in asymptomatic long‐term cigarette smokers in Western Australia is high, though significantly less than that found in a large study in North America. The authors postulate this is due to the relatively low rates of mycobacterium tuberculosis and soil‐derived fungal pulmonary infections in Western Australia, as well as a lower degree of urban air pollution.  相似文献   
63.
Purpose:To compare the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and optic nerve head (ONH) morphological parameters between obstructive sleep apnea (OSA) patients and age-matched controls using spectral domain optical coherence tomography (SD-OCT).Methods:This case control study was conducted in a multi-specialty tertiary care hospital from 2014 to 2016. Patients diagnosed to have OSA by overnight polysomnography were included in the study. Fifty eyes of 25 OSA patients with clinically normal optic disc were compared with 50 eyes of age-matched controls. The study population underwent detailed ophthalmological evaluation including SD-OCT.Results:There was significant thinning of the superior, inferior, and average RNFL in the OSA group when compared to controls. GCL analysis also showed a significant thinning of the six sectors as well as average and minimum ganglion cell layer + inner plexiform layer in OSA patients. The optic nerve head rim area was significantly decreased in OSA patients when compared to controls.Conclusion:OSA patients even with clinically normal optic disc showed significant decrease in the RNFL thickness, GCL thickness, and rim area when compared to age-matched controls. Hence, these patients constitute a high-risk population who need to be regularly screened and followed up for ocular co-morbidities.  相似文献   
64.
魔芋精粉的降血糖作用   总被引:6,自引:0,他引:6  
目的:研究魔芋精粉的降糖作用。方法:以不同剂量魔芋精粉ig正常小鼠和四氧嘧啶糖尿病小鼠,连续10d后,葡萄糖氧化酶法测定正常小鼠的空腹血糖、糖耐量试验以及四氧嘧 啶糖尿病小鼠的血糖尿病小鼠的血糖,以放射免疫法测定血清胰岛素。结果:魔芋精粉有降低正常小鼠血糖作用,呈一定量效关系趋势;且具有改善小鼠糖耐量作用,能明显降低四氧嘧啶糖尿病小鼠血糖,但因清胰岛素水平无明显影响。结论:魔芋精粉可能是通过影响糖代  相似文献   
65.
Opioids mediate their analgesic effects by activating mu-opioid receptors (MOR) not only within the central nervous system but also on peripheral sensory neurons. The peripheral analgesic effects of opioids are best described under inflammatory conditions (e.g., arthritis). The present study investigated the effects of inflammation on MOR binding and G-protein coupling of full versus partial MOR agonists in dorsal root ganglia (DRG) of primary afferent neurons. Our results show that Freund's complete adjuvant (FCA) unilateral hindpaw inflammation induces a significant up-regulation of MOR binding sites (25 to 47 fmol/mg of protein) on DRG membranes without affecting the affinity of either full or partial MOR agonists. In our immunohistochemical studies, the number of MOR-immunoreactive neurons consistently increased. This increase was mostly caused by small-diameter nociceptive DRG neurons. The full agonist DAMGO induced MOR G-protein coupling in DRG of animals without FCA inflammation (EC50 = 56 nM; relative Emax = 100%). FCA inflammation resulted in significant increases in DAMGO-induced MOR G-protein coupling (EC50 = 29 nM; relative Emax = 145%). The partial agonist buprenorphine hydrochloride (BUP) showed no detectable G-protein coupling in DRG of animals without FCA inflammation; however, partial agonist activity of BUP-induced MOR G-protein coupling was detectable in animals with FCA inflammation (EC50 = 1.6 nM; relative Emax = 82%). In behavioral studies, administration of BUP produced significant antinociception only in inflamed but not in noninflamed paws. These findings show that inflammation causes changes in MOR binding and G-protein coupling in primary afferent neurons. They further underscore the important differences in clinical studies testing peripherally active opioids in inflammatory painful conditions.  相似文献   
66.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
67.
报道4个N-(1-[1-乙氧羰基-3-(对甲)苯氨甲酰基]丙基甘氨酰}-N-取代甘氨酸(XI1~4)和5个1-[1-乙(或甲)氧羰基-3-(对甲)苯氨甲酰基]丙基-4-取代-1,4-哌嗪-2,5-二酮(XII1~5)共9个估计有血管紧张素转化酶抑制活性化合物的合成和鉴定。所有这些化合物及9个相应的酯(X1~9)均未见文献报道。药理初试结果,化合物XII2,XII5,XI4和XII1均有较强降压活性。  相似文献   
68.
69.

Background

Due to the growing number of elderly with advanced chronic conditions, healthcare services will come under increasing pressure. Teleconsultation is an innovative approach to deliver quality of care for palliative patients at home. Quantitative studies assessing the effect of teleconsultation on clinical outcomes are scarce. The aim of this present study is to investigate the effectiveness of teleconsultation in complex palliative homecare.

Methods/Design

During a 2-year recruitment period, GPs are invited to participate in this cluster randomized controlled trial. When a GP refers an eligible patient for the study, the GP is randomized to the intervention group or the control group. Patients in the intervention group have a weekly teleconsultation with a nurse practitioner and/or a physician of the palliative consultation team. The nurse practitioner, in cooperation with the palliative care specialist of the palliative consultation team, advises the GP on treatment policy of the patient. The primary outcome of patient symptom burden is assessed at baseline and weekly using the Edmonton Symptom Assessment Scale (ESAS) and at baseline and every four weeks using the Hospital Anxiety and Depression Scale (HADS). Secondary outcomes are self-perceived burden from informal care (EDIZ), patient experienced continuity of medical care (NCQ), patient and caregiver satisfaction with the teleconsultation (PSQ), the experienced problems and needs in palliative care (PNPC-sv) and the number of hospital admissions.

Discussion

This is one of the first randomized controlled trials in palliative telecare. Our data will verify whether telemedicine positively affects palliative homecare.

Trial registration

The Netherlands National Trial Register NTR2817  相似文献   
70.
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