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101.
Parasitology Research - Praziquantel (PZQ) is recommended by the WHO as the first line in treatment of schistosomiasis. Unfortunately, it exhibits low oral bioavailability which can compromise its...  相似文献   
102.
Screening of 18 bacterial honey isolates revealed that all the isolates were levansucrase producers. The most potent isolate that achieved the highest activity (45.66 U/ml) was identified as Bacillus subtilis NRC based on morphological examination and 16S rRNA. The results recorded the necessity of starch (5 g/L), baker's yeast (12.5 g/L), and AlCl3 (5 mM) in improvement of the enzyme productivity. The Bacillus subtilis levansucrase was eluted as a single protein in one purification step. The enzyme molecular weight was (14 kDa). It showed its optimum activity at 45°C and could retain 60% of its activity after incubation at 50°C for 2 h. Its optimum activity was obtained at pH 8.2 and the enzyme showed great pH stability in both acidic and alkaline ranges. Unlike, most levansucrases all tested metals had an adverse effect in enzyme activity. The enzyme had antioxidant activities and were characterized as spherical micro‐ and nanoparticles by transmission electron microscopy. The effect of growth conditions and medium composition in levan structure and its fibrinolytic activity was evaluated.  相似文献   
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The solitary fibrous tumor (SFT) is a rare mesenquimal neoplasm, found originally in association with the pleura. Recently, SFT was reported in others sites. The extension into adjacent structures is not uncommon. The meningeal involvement by SFT is rare and there has only twenty-six cases been reported previously in the literature. We report a case of a 25 years-old female patient with generalized tonic clonic seizures in the last six years. During the neurologic investigation, a tumor in the left occipital region of the brain was found. The patient underwent an occipital craniotomy with total resection of the tumor. The histopathological and immunohistochemical diagnosis was STF. After three years of follow-up, the patient remains stable, with a normal neurological exam. There is no sign of tumor recidive in the postoperative cranial tomography. We will briefly review the literature about STF.  相似文献   
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OBJECTIVE: A recurring question is whether evidence from systematic reviews has any impact on medical practice. We have studied this question in relation to some conclusions in seven reports, where relatively simple means to monitor trends could be used. RESULTS: As recommended, in the report preoperative routines, the number of preoperative examinations diminished at six hospitals, during around 3,000 operations studied, a savings of SEK 130 million. After the report on moderately elevated blood pressure, moderately elevated blood pressure sales of the preferred drugs, diuretics and beta-blockers, stopped falling while calcium blockers and ACE inhibitors stopped rising. As concluded in the report, general prostate cancer screening has not been introduced, but tests as a sign of opportunistic screening have increased. Bone density measurements were not recommended for screening, and sales of equipment have declined after the report. The use of neuroleptics as unspecific calming therapy for old persons was discouraged due to the serious side effects. The frequency of patients given this medication diminished from 34% to 28% at nursing homes after 1 year. For smoking cessation, the use of nicotine substitution medications has increased, which is in line with suggestions presented in the report. For stomach pain proton pump inhibitors given for functional dyspepsia have diminished in a region of the country after special efforts to disseminate the message. CONCLUSIONS: It appears to be possible to monitor changes in practice corresponding to selected conclusions in systematic reviews. After rather extensive disseminating efforts, some results look encouraging.  相似文献   
107.
A specially prepared olive leaf extract (EFLA 943) has been tested for its blood pressure lowering activity in rats rendered hypertensive by daily oral doses of L-NAME (NG-nitro-L-arginine methyl ester, 50 mg/kg) for at least 4 weeks. Oral administration of the extract at different dose levels at the same time as L-NAME for a period of 8 weeks showed a dose dependent prophylactic effect against the rise in blood pressure induced by L-NAME, best effects being induced by a dose of 100 mg/kg of the extract. In rats previously rendered hypertensive by L-NAME for 6 weeks and then treated with that dose of the extract for a further 6 weeks without discontinuation of L-NAME, normalisation of the blood pressure was observed. The findings confirm previous reports on the hypotensive effects of olive leaf. The special extract, EFLA 943, was shown to give consistent results with little individual variability. The antihypertensive effect of the extract may be related to a variety of factors involving reversal of vascular changes involved in the L-NAME induced hypertension.  相似文献   
108.
OBJECTIVE: To analyse the outcome of six children with Crigler-Najjar syndrome type I (CNS-I) and report the first three living-related liver transplants for this syndrome in Saudi Arabia and the Middle East. SETTINGS: To review the medical records of six children suffering from CNS-I, three of whom underwent living-related liver transplantation (LRLT) between 22 November 1998 and January 2001. MAIN RESULTS: Living-related liver transplantation was performed in three children with a pre-transplant unconjugated bilirubin level of 362, 381 and 502 micromol/L, respectively, despite daily phototherapy of >or= 12 h. Two of the transplanted children developed acute hepatocellular rejection, which was successfully treated with methylprednisolone pulse therapy. One tested cytomegalovirus positive (using the PP65 method), but showed no signs of clinical infection and was treated with ganciclovir. One patient had a biliary leak at the cut surface of the graft which was surgically repaired. Post-operative bilirubin levels returned to normal in all three transplanted children and no further phototherapy was required. One patient, who was not transplanted but received phototherapy, developed severe neurological damage prior to the start of our living-related liver transplant programme with a bilirubin level of 450 micromol/L, her sister is still awaiting transplantation. A 14-yr-old child with a bilirubin level of 420 micromol/L is presently undergoing phototherapy whilst awaiting orthotopic liver transplantation because of the lack of a suitable living-related donor. Six siblings of the six children in our series were reported dead by the families. CONCLUSION: Crigler-Najjar syndrome type I is a relatively common disease in Saudi Arabia for which LRLT is a curative treatment when performed at an early age before the development of kernicterus and neurological deficiency. In countries where there is a severe shortage of cadaveric organs, as is the case in Saudi Arabia, LRLT is the optimum treatment modality for this syndrome.  相似文献   
109.
BACKGROUND: The plasma membranes of endothelial cells are sites of physiologic injury caused by superoxide attack, whether the radicals are generated within the cell (i.e., from enzymatic sources such as xanthine oxidase or from ischemically injured mitochondria) or are generated within the interstitial spaces by activated neutrophils or macrophages. An extracellular superoxide dismutase (ECSOD) electrostatically bound to endothelial surfaces partially protects against this oxidative attack. To provide a therapeutic equivalent of this ECSOD activity, we evaluated the product of a fusion gene encoding a chimeric manganese SOD (chimeric-SOD) and the carboxyl-terminal 26-amino acid basic "tail" from ECSOD with high affinity for heparin-like proteoglycans on cell surfaces. METHODS: We tested the chimeric-SOD in isolated rabbit hearts during warm and cold ischemia. RESULTS: When perfused through an isolated rabbit heart, chimeric-SOD bound to endothelial surfaces and was displaced by a bolus dose of heparin. In an established model of no-flow ischemia followed by reperfusion of the isolated rabbit heart, the chimeric-SOD was as protective as native Mn-SOD or Cu,Zn-SOD, but at doses nearly 2 orders of magnitude lower. In a rabbit-heart preservation model, the chimeric-SOD provided better recovery of function after 4 hours of cold ischemia than did University of Wisconsin cardioplegia solution. CONCLUSION: This chimeric-SOD can bind to cell surfaces and may aid in preventing superoxide-mediated endothelial damage and may function as a rational therapeutic agent for treating free-radical-mediated diseases.  相似文献   
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