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991.
Cystic lesions of the pancreas are infrequent, estimated at only some 1% of all pancreatic tumours and at some 10% of all pancreatic cysts. The pre-operational diagnosis is important for a suitable treatment, with valuable radiological techniques available today such as ultrasound, computerised tomography and magnetic resonance. In spite of this we have to accept that we are facing a group of tumours whose diagnosis is difficult, due to the great variety of cellular types existing within them.  相似文献   
992.
BACKGROUND: On 17 November 2001, less than 900 days after the end of one of the largest population displacements since 1945, the, Kosovo electorate voted for their new self-government. An Assembly was formed in 2001 and a Health Minister, Dr Numan Balic, appointed in March 2002. He has inherited a health service that still reels from many years of neglect while it struggles to implement an ambitious health reform programme. METHODS: An analysis of UNMIK Regulations and available grey literature within Kosovo has formed the basis of material for this article. In addition, the authors collected, by informal interview, the opinions of international and Kosovars actively employed within the health sector. The authors would wish to acknowledge the contribution of Dr Hannu Vuori, Principal International Officer, Ministry of Health, Kosovo for his insight and suggestions. RESULTS: The analysis reveals that the current health system is inequitable and inefficient. The health sector reforms initiated by the international community are desperately needed: it is purported that one-in-three Kosovars cannot afford to access health care when ill. However, the combined legacy of neglect, the current status of the health service and the new Assembly regulations present significant challenges to health reform. CONCLUSIONS: Under the gaze of the newly formed Assembly, as well as the watchful eye of the United Nations Interim Administrative Mission in Kosovo, the Minister will take on the arduous responsibility of governing the Kosovo health sector. In any context implementing reform is difficult, in Kosovo it may be even more so and the international community should not exclusively focus on other world-trouble spots when many challenges remain to be addressed.  相似文献   
993.
The angiotensin-converting enzyme inhibitors cilazapril, quinapril and ramipril are reduced at a hanging mercury drop electrode in the pH range 3.5-13 using Britton-Robinson buffers as supporting electrolyte and KCl as ionic medium. Square wave voltammetry has proved to be the most suitable electroanalytical technique for the quantitative voltammetric determination of these antihypertensive drugs. Optimisation of the chemical and instrumental variables was carried out. Analyses were performed in 0.02 M borate buffer at pH 9.5 and 0.5 M KCl as ionic medium, using a pulse amplitude of 50 mV and a frequency of 150 Hz. A linear relationship between peak current and concentration was found in the interval 0.5-8 microg/ml for cilazapril and up to 6 microg/ml for quinapril and ramipril, allowing the direct determination of their pharmaceutical formulations alone or mixed with hydrochlorothiazide. Good accuracy and repeatativity were obtained.  相似文献   
994.
A simple, sensitive and rapid spectrofluorimetric method to determine velnacrine, a cholinesterase inhibitor, has been developed and validated. The influence of pH, temperature, ionic strength, presence of excipients, metal ions and surfactants on the fluorescence intensity has been studied. The proposed method allows the determination of 5-100 ng ml(-1) of velnacrine in aqueous solution containing sodium acetate buffer (pH 5.6; 0.04 M) with lambda(excitation) 242 nm and lambda(emission) 359 nm. The detection and quantitation limits were 1.7 and 4.5 ng ml(-1) respectively. The method was successfully applied to the determination of velnacrine in human serum and urine.  相似文献   
995.
AIM: Cysteinyl leukotrienes are important pro-inflammatory mediators in the pathogenesis of asthma, while leukotriene C4 synthase is a key enzyme in their biosynthesis. Our aim is to evaluate whether responsiveness to leukotriene receptor antagonists was determined by expression of the variant (C) or wild-type (A) polymorphism of this enzyme. METHODS: We carried out a retrospective analysis of 8 randomised, placebo-controlled trials performed in our department in mild-to-moderate asthmatics. In all trials, effect of leukotriene receptor antagonist was compared to placebo, where the primary outcome was bronchial hyperresponsiveness to adenosine monophosphate or methacholine. Secondary outcomes were forced expiratory volume in 1 second, exhaled nitric oxide and peripheral blood eosinophils. RESULTS: For the primary outcome of attenuation of bronchial hyperresponsiveness by leukotriene receptor antagonist vs placebo, there were significant effects within each genotype on adenosine monophosphate (AMP) (n = 78): 2.21 and 2.07-fold improvements for AA and AC/CC, respectively; while for methacholine (n = 81) there were 1.39 and 1.36-fold improvements, respectively. There were no significant differences between genotypes (i.e. AA vs AC/CC): geometric mean fold-differences of 1.07 (95%CI 0.63-1.81) and 1.02 (95%CI 0.70-1.50) for AMP and methacholine, respectively. There were also no differences between genotypes for all secondary outcomes. CONCLUSION: Polymorphisms of leukotriene C4 synthase did not determine responsiveness, in terms of attenuation of bronchial hyperresponsiveness, to leukotriene receptor antagonists in mild-to-moderate asthmatics. Further prospective large pharmacogenetic studies are required in more severe patients, where there may be greater improvements in pharmacodynamic outcome measures such as bronchial hyperresponsiveness and exhaled nitric oxide.  相似文献   
996.
PURPOSE: This study was to develop and validate a new chiral HPLC-UV method for the quantitative analysis of enantiomeric ritalinic acid (RA) in human plasma. METHODS: An alpha1-acid glycoprotein column was used with the mobile phase containing 0.4% acetic acid and 0.1% dimethyloctylamine, pH 3.4. The detection of enantiomeric RAs was at 220 nm. RESULTS: A baseline separation for d- and l-RA was achieved by a separation factor of 2.08. Methylphenidate, the precursor of RA, was eluted with the front solvent, and thus does not interfere in the analysis of RA in our method. The assay was successfully applied for the in vitro analysis of enantiomeric ritalinic acids produced by human and dog plasma and dog liver. CONCLUSIONS: Data demonstrated that the esterase(s) in human plasma metabolize d-methylphenidate faster than its l-isomer. The yielded intrinsic clearances (Clint) are 1.02 and 2.17 microl/min/mg protein, respectively, for d and l-methylphenidate.  相似文献   
997.
998.
999.
Effect of impact on different regions of the head of lambs   总被引:3,自引:0,他引:3  
The heads of anaesthetized lambs aged 4-5 weeks were subjected to impact (temporal, frontal or occipital) of constant strength with a humane stunner. Two hours later, the brains were perfusion-fixed with 4% paraformaldehyde and serial whole coronal slices processed by routine methods. Sections were stained with haematoxylin and eosin or labelled with a monoclonal antibody to amyloid precursor protein, a sensitive marker of axonal injury and neuronal reaction. Microscopical evaluation of axonal, neuronal and vascular damage was performed with a quantitative grid system. Frontal impact produced the greatest damage, followed by occipital then temporal impact. An unusual lesion found in the majority of lambs subjected to impact was multifocal necrosis of the cerebellar granular layer. The findings should assist clinicians in evaluating the probable outcome of traumatic head injury in domestic animals. Copyright Harcourt Publishers Ltd.  相似文献   
1000.
OBJECTIVE: To analyze the effect of abdomen release in the prone position on oxygenation in an experimental model of acute lung injury. DESIGN: Experimental randomized controlled study. SETTING: Experimental laboratory of a tertiary university hospital. PARTICIPANTS: Mixed-breed adolescent pigs weighing between 25-31 kg. INTERVENTIONS: Thirty minutes after pulmonary edema was produced with oleic acid, the animals were turned prone and randomized into two groups: group I or control (n = 9), lying directly on the operating table; and group II (n = 11) with abdomen release, with positioning rolls under the upper part of the chest wall and the pelvis to allow free movement of the abdomen. MEASUREMENTS AND RESULTS: The gas exchange, respiratory mechanics, hemodynamics, intra-abdominal pressure (IAP) and the extravascular lung water (EVLW), determined by double indicator dilution method (DI), were recorded at baseline (time 0) and at 30, 60, 90, 120 and 150 min. The PaO2/FIO2 increased in both groups at 30 min after the pigs were placed in the prone position (time 60) and then decreased progressively until the end of the experimental period, with no statistical differences between the groups at any time (73.1 +/- 14.5 vs 79.5 +/- 14.9 at 150 min). Abdomen release was not associated with changes in the respiratory mechanics, EVLW or intra-abdominal pressure. CONCLUSIONS: Abdomen release in prone position does not improve oxygenation in an experimental model of acute lung injury.  相似文献   
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