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31.
Teb(medicine)as described by Avicenna on the opening pages of the al-Qānūn fīal-Tibb(The Cannon of Medicine)was"a science by which one learns the conditions of the human body in health and in the nonexistence of health to keep health or to bring it back".According to Avicenna’s Canon of Medicine and other traditional Persian medicine(TPM)resources,the observance of the six essential qualities provides guidance to any medical intervention.  相似文献   
32.
Studies in the White Nile area of the Sudan have shown that Zebu cattle acquire a high degree of resistance to Schistosoma bovis as a result of repeated natural exposures without, however, being able to eliminate their populations of adult schistosomes, although these do show greatly suppressed fecundity. To test whether these adult worms are necessary for the maintenance of resistance we cured six "naturally resistant" cattle (TC group) with a double treatment of 25 mg/kg praziquantel and compared their response to a 70,000 cercariae challenge with groups of "naturally resistant" but untreated cattle (UC group) and with previously unexposed, challenged cattle (CC group). Challenge was carried out 7 weeks after the second dose of praziquantel. The results confirmed that untreated cattle are "naturally resistant" and also showed that resistance was not abrogated by cure of the naturally-acquired infections. Thus, fecal egg counts after challenge reached mean maxima of 2,432 eggs per gram (epg) in the CC, but only 5 epg and 28 epg in the TC and UC groups, respectively. Similarly, mean worm counts were 85% and 69% lower in the TC and UC groups, respectively, and mean tissue egg densities were reduced by 72-99%, and 56-80%. Histopathologically, the TC and UC groups were also far less affected than the CC. Effective praziquantel treatment does therefore not destroy naturally acquired resistance to S. bovis, and may benefit infected livestock even in the absence of transmission control. The situation in human schistosomiasis is less clear, but there are several epidemiological and experimental indications of a similar conclusion for S. mansoni.  相似文献   
33.
Journal of Digital Imaging - Accurate information of the lung shape analysis and its anatomical variations is very noticeable in medical imaging. The normal variations of the lung shape can be...  相似文献   
34.
In this work, patients with severe coronary disease and chronic occlusion of the right coronary artery (RCA) are studied. In this clinical situation, the collateral circulation is an important factor in the preservation of the myocardium until reperfusion of the area at risk. An accurate estimation of collateral flow is crucial in surgical bypass planning as it can influence the outcome of a given treatment for a given patient. The evaluation of collateral flow is frequently achieved using an index (CFI, Collateral Flow Index) based on pressure measurements.Using a model of the coronary circulation based on hydraulic/electric analogy, we demonstrate, through theoretical simulations, that a wide range of fractional collateral flow values can be obtained for any given distal pressure difference depending on the values of the capillary and collateral resistances.  相似文献   
35.
This work presents smart pathways to enhance the photocatalytic activity of TiO2via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO2 photocatalysts and investigates the unique and unusual fluorination of the floated products. Our investigations indicate that the crystalline structure of the photocatalysts was a mixture of anatase and brookite phases and that the nanoparticles of the synthesized nanocomposites had nanometric sizes (4–25 nm). The F–Pt co-doped TiO2 nano-photocatalysts demonstrated degradation of sulfamethoxazole (SMX) drug of >93% within 90 min under direct solar light and 58% degradation within 360 min under a solar simulator. Thus, co-doping TiO2 with F and Pt atoms to form F–Pt co-doped TiO2 nanocomposite is an efficient pathway to achieve high photocatalytic performance escorted with the formation of floating metal-fluoropolymer, unlike pristine TiO2 which has less photocatalytic degradation and no generation of a floating polymer. Our photocatalytic protocol demonstrates that the degradation of SMX started with redox reactions of oxygen and water absorbed on the surface of the prepared nanocomposites to form superoxide anions (O2˙) and hydroxy radicals (˙OH) which have oxidation superpower. The resultant products were subsequently fluorinated by fluoride radical ions and floated as metal-fluoropolymer.

This work presents smart pathways to enhance the photocatalytic activity of TiO2via co-doping with fluorine (F) and platinum (Pt) to form F–Pt co-doped TiO2 photocatalysts and investigates the unique and unusual fluorination of the floated products.  相似文献   
36.
Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.

Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production.  相似文献   
37.
38.
Pentoxifylline reduces peritoneal adhesions and increases peritoneal fibrinolysis in rodents. Furthermore, the activation of the fibrinolytic system by streptokinase leading to degradation of fibrin is effective in the prevention of adhesion formation. We have investigated the effects of pentoxifylline and streptokinase alone and/or coadministration on postoperative intra-abdominal adhesion formation in adult female NMRI mice. Drugs were administered from the day of surgery until 10 days after surgery. At relaparotomy 11 days after surgery, the abdomen was opened, and the adhesions were graded in a blinded fashion utilizing the classification system described. Oral gavage administration of lower doses of pentoxifylline (3.125, 6.25, and 12.5 mg/kg) had no significant effect on postsurgical adhesion formation, while the higher doses of pentoxifylline (25 and 50 mg/kg) significantly decreased postsurgical adhesion formation. Moreover, intraperitoneal injection of lower doses of streptokinase (9.375, 18.75, and 37.5 unit/kg, i.p.) had no significant effect on postsurgical adhesion formation, while the higher doses of streptokinase (75 and 150 unit/kg) significantly decreased postsurgical adhesion formation. In other series of experiments, coadministration of lower doses of pentoxifylline and streptokinase doses, which were ineffective when given alone, significantly decreased postsurgical intra-abdominal adhesion formation compared with streptokinase control group. The results suggest that pentoxifylline may interfere with streptokinase in the reduction of postoperative intra-abdominal adhesion formation by enhancing local fibrinolytic activity.  相似文献   
39.
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions.  相似文献   
40.

Background and study aims

Helicobacter pylori (H. pylori) has been implicated in the pathogenesis of most important gastro-duodenal diseases, such as gastritis, peptic ulcer disease (PUD) and gastric cancer. H. pylori upregulates the expression and activity of several matrix metalloproteinases (MMPs) in the gastric mucosa, but the role of MMP-3 and MMP-9 in infected patients with H. pylori have not been clearly defined yet. We examined mucosal MMP-3 and MMP-9 mRNA levels in gastric mucosa of H. pylori infected patients and evaluated the effects of virulence factors cagA and vacA allelic variants on these levels. We also determined correlation between mucosal MMP-3 and MMP-9 mRNA levels and types of disease.

Patients and methods

Total RNA was extracted from gastric biopsies of 50 H. pylori-infected patients and 50 H. pylori-negative patients. Mucosal MMP-3 and MMP-9 mRNA expression level in H. pylori-infected and non-infected gastric biopsies were determined by real time-polymerase chain reaction (PCR). Presence of vacA (vacuolating cytotoxin A) and cagA (cytotoxin associated gene A) virulence factors were evaluated using PCR.

Results

The levels of MMP-3 in gastric mucosa were not different between H. pylori-positive and H. pylori-negative patients. There was no correlation between MMP-3 mRNA expression and virulence factor (cagA and vacA allelic variants) and the different types of disease (gastritis and PUD) in infected patients. But MMP-9 mRNA expression was significantly higher in biopsies of H. pylori-infected patients compared to H. pylori-negative patients. Also mucosal MMP-9 mRNA expression in H. pylori-infected patients was significantly associated with cagA status PUD.

Conclusion

Our results suggest that MMP-9 might be involved in the pathogenesis of H. pylori. PUD could be associated with cag PAI-dependent MMP-9 upregulation.  相似文献   
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