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41.
  总被引:4,自引:0,他引:4  
Acute pancreatitis (AP) is a common acute abdomen in clinic with a rapid onset and dangerous pathogenetic condition AP can cause an injury of intestinal mucosa barrier, leading to translocation of bacteria or endotoxin through multiple routes, bacterial translocation (BT), gutorigin endotoxaemia, and secondary infection of pancreatic tissue, and then cause systemic inflammatory response syndrome (SIRS) or multiple organ dysfunction syndrome (MODS), which are important factors influencing AP's severity and mortality. Meanwhile, the injury of intestinal mucosa barrier plays a key role in AP's process. Therefore, it is clinically important to study the relationship between the injury of intestinal mucosa barrier and AP. In addition, many factors such as microcirculation disturbance, ischemical reperfusion injury, excessive release of inflammatory mediators and apoptosis may also play important roles in the damage of intestinal mucosa barrier. In this review, we summarize studies on mechanisms of AP.  相似文献   
42.
The prevalent Ala222Val single nucleotide polymorphism of the MTHFR gene has been shown to be associated with type II diabetes. The objective of the present study was to find out whether there is genetic predisposition for development of acute myocardial infarction in type II diabetes mellitus among South Indian Tamil population. PCR-based restriction enzyme analysis was performed in DNA isolated from 120 acute myocardial infarction patients with diabetes mellitus and 100 non diabetic healthy individuals with no documented cardiovascular diseases. The results indicate that the MTHFR 677TT genotype is absent in both case and controls. The MTHFR 677CT genotype was observed among 32 (26.7 %) cases and 20 (20%) controls and the MTHFR 677CC genotype among 88 (73.3%) cases and 80 (80%) controls. The allelic frequencies were in accordance to Hardy Weinberg equilibrium. There was no statistical difference in genotype distribution between cases and controls. In conclusion, we suggest that the analysis of MTHFR genotyping for C677T polymorphism alone need not be considered to find out whether there is genetic predisposition for development of acute myocardial infarction in type II diabetes mellitus among South Indian Tamil population.  相似文献   
43.
Objective To investigate the relationship between serum resistin level and acute coronary syndrome (ACS) or stable angina pectoris (SAP). Methods Sixty-five patients, with coronary artery disease, were enrolled and divided into three subgroupsacute myocardial infarction (AMI), unstable angina pectoris (UAP) and SAP, and 26 healthy people were recruited as controls in the cross-sectional study. Serum resistin levels were determined by ELISA (enzyme-linked immunosorbent assay), and WBC (white blood cell count), hsCRP (high sensitive C-reaction protein), CKmax (maximum ofcreatinkinase), CK-MBmax (maximum of isozyme of creatinkinase) and cTnImax (maximum oftroponin) were measured by standard laboratory methods. Results The serum resistin levels were 4 folds higher in AMI patients, 2.43 folds in UAP patients and 1.12 folds in SAP patients than in the healthy controls (P<0.05). The resistin levels were also significantly different between AMI [(8.16±0.79) ng/ml], UAP [(5.59±0.75) ng/ml]and SAP [(3.45±0.56) ng/ml] groups (P<0.01); WBC, hsCRP, CKmax, CK-MBmax and cTnImax were significantly increased in AMI patients over UAP and SAP patients. Spearman analysis showed that serum resistin levels were positively correlated with WBC (r=0.412, P=0.046), hsCRP (r=0.427, P=0.037), CKmax, CK-MBmax and cTnImax (r=0.731, 0.678, 0.656; P<0.01). ConclusionSerum resistin levels increased with inflammatory factors and myocardial impairment. The results suggest that human resistin might play an important role in the pathogenesis of atherosclerosis and AMI as an inflammatory factor.  相似文献   
44.
The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(II) is significantly higher than that of the cells treated with Fe(III) (P<0.05). Fe(II) at a concentration >1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(III). LDH release investigation suggests that Fe(II) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(II) were higher than those of the cells treated with Fe(III), although both of them increased with raising iron supply levels. The results indicate that both Fe(II) and Fe(III) could reduce the cellular antioxidase gene expression at high levels. Project supported by the International Cooperative Project from the Ministry of Science and Technology of China (No. 2006DFA31030), the Bureau of Science and Technology of Zhejiang Province (No. 2006C32019) and HarvestPlus-China (No. 8022), and the Program for Changjiang Scholars and Innovative Research Team in University of China (No. IRT0536)  相似文献   
45.
The objective of this study was to investigate whether acute pain in abused children was under recognized by doctors and nurses compared to children evaluated for accidental injuries. We hypothesize that an abused child’s reaction to physical pain could be an additional symptom of this challenging diagnosis. For the observational prospective case control study in an emergency department, children were eligible when: younger than six years old, the reported trauma occurred within the previous seven days, the trauma comprised a bone injury or burn, and the child was able to express his or her pain. The case group comprised children for whom the medical team reported their abuse suspicions and supporting information to a court, and whose cases of abuse were subsequently confirmed. The control group consisted of children with a plausible cause for their injury and no obvious signs of abuse. The children were matched according to their age and type of trauma. The pain was assessed by doctors and nurses before analgesic administration using a certified pain scale.Among the 78 included children, pain was significantly less recognized in the abused children vs. the controls (relative risk = 0.63; 95% CI: 0.402–0.986; p = 0.04). We observed a discrepancy between the nurses’ and doctors’ scores for the pain assessments (Kappa coefficient = 0.59, 95% CI: 0.40–0.77). Our results demonstrate that pain expression in abused children is under recognized by medical staff. They also suggest that abused children may have reduced pain expression after a traumatic event. Paying particular attention to the pain of abused children may also optimize the analgesic treatment.  相似文献   
46.
INTRODUCTION Telomeres are distinctive DNA-protein struc-tures that cap the ends of linear chromosomes.It is very important to keep the chromosomes stabilization.Telomerase activity is closely linked to attainment of cellular immortality,a step in carcinogenesis,while lack of such activity contributes to cellular senes-cence.Telomerase is activated in more than85%ofmalignant tumors(Hiayma et al.,1997).Human te-lomeric repeat binding factor1(TRF1)is a telomere associated with proteins a…  相似文献   
47.
    
Inflammation plays an important role in the development of acute lung injury (ALI). Severe pulmonary inflammation can cause acute respiratory distress syndrome (ARDS) or even death. Expression of proinflammatory interleukin-‍1β (IL-‍1β) and inducible nitric oxide synthase (iNOS) in the process of pulmonary inflammation will further exacerbate the severity of ALI. The purpose of this study was to explore the effect of Palrnatine (Pa) on lipopolysaccharide (LPS)-induced mouse ALI and its underlying mechanism. Pa, a natural product, has a wide range of pharmacological activities with the potential to protect against lung injury. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) assays were performed to detect the expression and translation of inflammatory genes and proteins in vitro and in vivo. Immunoprecipitation was used to detect the degree of P65 translocation into the nucleus. We also used molecular modeling to further clarify the mechanism of action. The results showed that Pa pretreatment could significantly inhibit the expression and secretion of the inflammatory cytokine IL-1β, and significantly reduce the protein level of the proinflammatory protease iNOS, in both in vivo and in vitro models induced by LPS. Further mechanism studies showed that Pa could significantly inhibit the activation of the protein kinase B (Akt)/nuclear factor-κB (NF-κB) signaling pathway in the LPS-induced ALI mode and in LPS-induced RAW264.7 cells. Through molecular dynamics simulation, we observed that Pa was bound to the catalytic pocket of Akt and effectively inhibited the biological activity of Akt. These results indicated that Pa significantly relieves LPS-induced ALI by activating the Akt/NF-κB signaling pathway.  相似文献   
48.
    
Congestive heart failure (CHF) has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout (necrosis and apoptosis) plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells (CSCs) within the heart divide symmetrically and/or asym-metrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells (BMCs) to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by dif-ferentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animal CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, pla-cebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction.  相似文献   
49.
Winegrape is an important perennial crop in California, USA. Each year California winegrape farming consumes about 20 million kilograms of pesticides that have been a pollutant source to the fresh water systems of the state. The variation of pesticide use among winegrape growers has been significant. It has been observed that some growers have developed effective ways to reduce pesticide use, yet control pests efficiently to ensure harvest. Identification of the growers with low and high pesticide use is very helpful to extension programs that aim on reducing pesticide environmental risk. In this study, an index approach is proposed to quantitatively measure pesticide use intensity at grower level. An integrated pesticide use index is developed by taking pesticide quantity and toxicity into account. An additive formula and a multiplying formula were used to calculate the pesticide use index, i.e., PUI and PUIM. It was found that both PUI and PUIM were capable of identifying the low and high pesticide users while PUI was slightly more conservative than PUIM. All pesticides used in California winegrape farming were taken into account for calculating the indices. Madera County, one of the largest winegrape producers in California, was taken as an example to test the proposed approach. In year 2000, among the total 208 winegrape growers, 28 with PUI≤10 and 34 with 10<PUI≤20 were identified as low pesticide users who were characterized with both low quantity and low toxicity of pesticide use. Most of the growers had small-sized vineyards, i.e., one field and small planted areas. Furthermore, they had very low pesticide use intensity, used only 1–2 types of pesticides (mainly fungicides), applied few pesticides (1–3 only), and emphasized the use of low toxicity compounds. Meanwhile, 19 growers with PUI>60, identified as high pesticide users, had large-sized vineyards, i.e., more fields and large planted areas. They used all types of pesticides and many compounds, which indicated that their pest controls heavily depended on pesticides rather than on-farm management. Through the case study, the proposed approach proved to be useful for analyzing the growers’ pesticide use intensities and interpreting their pesticide use behaviors, which led to a new start point for further investigation of searching ways to reduce pesticide environmental risk.  相似文献   
50.
目的:探讨αlb基因工程干扰素治疗和预防流行性出血性结膜炎的疗效。方法:选同期门诊AHC双眼发病患者48例,单眼发病患者32例,均随机分成治疗组和对照组,以干扰素滴眼液和无环鸟苷滴眼液做治疗和预防对照,均双眼点药,健眼做预防用药。结果:双眼发病患者干扰素治疗组治愈时间平均5.33d,无环鸟苷对照组8.27d,经秩和检验有显著差异(P<0.05);单眼发病患者中,健眼干扰素组6例发病,无环鸟苷组13例发病,经统计学处理有显著差异(P=0.035)。结论:αlb基因工程干扰素滴眼液治疗AHC疗效显著,且时间短,见效快,并对健眼有明显的预防发病作用。  相似文献   
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