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51.
Cardiopulmonary bypass, initiates a generalised response, which is primarily defensive in nature. This response is self regulated and terminated spontaneously. Obvious problems are complement and leucocyte activation, but several other cascades are also stimulated, which interact, accentuate or modulate this response. These supporting cascades include, release of inflammatory cytokines, an activation of kallikrein system, clotting and fibrinolytic mechanisms, and arachidonic acid metabolism. Because of an effective autoregulatory mechanism, only a small proportion of patients (<3%), undergoing cardiopulmonary bypass are adversely effected by this process. Prognosis of these patients is often unpredictable, but in general, high risk patients are likely to suffer most. A number of specific and non specific artificial measures have been introduced to control postperfusion problems, resulting from this process. These control measures are usually effective against a specific component of this generalised problem, and often fail to achieve desired effects. Efficacy of control measures is further limited by a continued activation of complement and leucocytes, via interactions between the mentioned inflammatory cascades. In view of these limitations, we have introduced certain modifications in our previously reported control strategy. These include an early identification of high risk and susceptible individuals and using specific inhibitors of complement activation for both initial and terminal stages. 相似文献
52.
BACKGROUND: Postbypass refractory right ventricle (RRV) may develop due to right ventricular (RV) ischemia or infarction. In cases with RV infarction, recovery is often prolonged and salvage rate is extremely poor. In this retrospective study, we have examined the role of right ventricular exclusion (RVE), as a possible option to conventional weaning or bridging to heart transplant (B-HTX), in patients who were unsuitable for heart transplant. METHODS: During last 5 years, cumulative incidence of postbypass refractory circulatory failure (RCF) in our adult patients was 0.39% (26/6542). This problem was caused by a RRV in 17 (65%) patients. After CABG, these patients developed a grossly distended and poorly contracting RV (RVEDV: 330-400 ml, RVEF: 0-10%), high central venous pressure (> or =18 mmHg) and an inadequate aortic pressure for weaning off cardiopulmonary bypass. Three patients, who were unacceptable for HTX under UNOS program (age >65 years), were weaned off bypass after RVE, and remaining patients with RVAD (n=3) or BiVAD support, depending upon their concomitant moderate or poor left ventricular performance. RESULTS: The significant predictors of RRV by univariate analysis were; 2nd or 3rd redo CABG for a recent myocardial infarction, and failed graft angioplasty. Hospital mortality (14-60 days) was 0/3, 3/3 and 3/11 for the patients weaned off with RVE, RVAD and BiVAD respectively. At 3 years, overall salvage rate was 9/17 (RVE: 3/3, BiVAD B-HTX 4/6 + 2 weaned with BiVAD support). CONCLUSION: Right ventricular exclusion is a possible option to conventional B-HTX with mechanical support, in patients who develop postinfarct RRV and are unsuitable for transplant. 相似文献
53.
Hyperglycemia is implicated to play a major role in development of diabetic neuropathy. Since most of the diabetics are hyperglycemic much before they develop full-blown diabetes, we felt, it would be very important to know the effects of acute hyperglycemia on nerve function so that early pathophysiological events could be understood and appropriate therapeutic intervention can be made. Moreover, effect of acute hyperglycemia on motor nerve conduction velocity (MNCV) and nerve blood flow (NBF) is not known. Hence, we studied the effects of acute hyperglycemia on sciatic MNCV and sciatic NBF in healthy male Sprague-Dawley (SD) rats. Three different animal models of acute hyperglycemia (50% glucose (3 g kg(-1), i.v. (intra-venous) or i.p. (intra-peritoneally)) or 24 h post-streptozotocin (STZ) injected rats were used. Acute hyperglycemia but not mannitol or sucrose significantly attenuated MNCV and NBF. Adenosine (10 mg kg(-1), i.p.) prevented the acute hyperglycemia-induced attenuation of MNCV and NBF in all the three rat models of acute hyperglycemia. Adenosine effects were blocked by theophylline (50 mg kg(-1), i.p.) suggesting the role of adenosinergic receptor mediated mechanisms in acute hyperglycemia-induced neuropathy. Acute glucose administration in 8 weeks, STZ diabetic rats did not further affect MNCV or NBF. Adenosine (10 mg kg(-1), i.p.) did not produce any adverse effects on the blood pressure and heart rate. From the results, we conclude that acute hyperglycemia attenuates MNCV and NBF via an adenosinergic receptor-dependent mechanism. 相似文献
54.
Rodrigo Guellner Ghedini Julio de Oliveira Espinel Elaine Aparecida Felix Artur de Oliveira Paludo Rodrigo Mariano Arthur Rodrigo Ronconi Holand Cristiano Feijó Andrade 《Jornal brasileiro de pneumologia》2013,39(4):490-494
Every year, a large number of individuals become dependent on mechanical
ventilation because of a loss of diaphragm function. The most common causes are
cervical spinal trauma and neuromuscular diseases. We have developed an
experimental model to evaluate the performance of electrical stimulation of the
diaphragm in rabbits using single-channel electrodes implanted directly into the
muscle. Various current intensities (10, 16, 20, and 26 mA) produced tidal
volumes above the baseline value, showing that this model is effective for the
study of diaphragm performance at different levels of electrical stimulation 相似文献
55.
56.
Dorota Korycińska-Chaaban Edyta Ciecieląg Elżbieta Szponar Artur Kościesza Maria Nowacka Kamil Konrad Hozyasz 《Pediatria polska》2014
Phenylketonuria (PKU) is an autosomal recessive metabolic disease caused by an error of phenylalanine metabolism. Delayed treatment or treatment performed unsystematically might lead to neurological disorders and progressive intellectual disability. In the Prader-Willi syndrome (PWS) clinical manifestations change with age. Feeding difficulties resulting from the poor suck and hypotonia are typical in the neonatal period and early infancy. As patients grow their activities increase, muscle tone improves, the extreme hyperphagia appears – the main cause of obesity. Mental development of patients is usually mildly retarded. We report the case of a patient affected by two genetic diseases: PKU and PWS. Variety of clinical symptoms and abnormal results of laboratory analyses make the correct diagnosis difficult. Elevated phenylalanine level in screening newborn test, disorders of muscle tone, poor suck, and low urine biopterin concentration did not allow to clearly rule out the hyperphenylalaninemia caused by a tetrahydrobiopterin deficiency (BH4). Data from obstetric anamnesis and the early postnatal clinical findings suggested the PWS. Hyperphagia and the increased risk of carbohydrates tolerance disorders in patients with PWS make it very difficult to balance properly the low-phenylanine diet necessary in PKU treatment. The patient presented by us needs well-coordinated multidisciplinary medical care which aims to provide proper physical development and to support the boy's mental potential as well as appropriate functioning in the society. 相似文献
57.
58.
Kavitha Kothur Subhash Kaul S. Rammurthi V. C. S. Srinivasarao Bandaru Suvarna Alladi T. Suryaprabha K. Rukmini Mrudula 《Annals of Indian Academy of Neurology》2012,15(1):35-38
Cerebral venous thrombosis developing concurrently with active ulcerative colitis poses a therapeutic dilemma. We report the case of a 31-year-old woman who developed dural venous sinus thrombosis during the course of active ulcerative colitis in whom we accomplished clot lysis using intrasinus urokinase. The success of the procedure was assessed by improvement in the patient''s neurological condition and resolution of imaging features without any bleeding complications. We also reviewed literature on various modalities of treatment of sinus venous thrombosis in patients with ulcerative colitis and outcome. 相似文献
59.
Background
India had around 158 million children under the age of 6 and about 26 million births in 2015. In the same year, India's Integrated Child Development Services Scheme served about 82 million children under 6 years and over 19 million pregnant women and lactating mothers. These 102 million beneficiaries received services in about 1.3 million centres.Method
This paper reviews the growth of the Scheme and considers challenges to scaling up quality with equity based on results of large‐scale national or multistate studies.Results
The Scheme is associated with decreased malnutrition and better child development. The size and diversity of the country, the policy context, funding mode and lack of community awareness and engagement have hindered scaling up access while the approach to service delivery, low institutional capacity and poor infrastructure have impeded scaling up of implementation quality.Conclusions
This review illustrates the challenges associated with scaling‐up access and implementation quality of a multicomponent, integrated early childhood programme in a large, diverse country. The future success of the Integrated Child Development Services will depend on how well it adheres to quality standards and how well it evolves to address current weaknesses. 相似文献60.
Rakowski Tomasz Siudak Zbigniew Dziewierz Artur Plens Krzysztof Kleczyński Paweł Dudek Dariusz 《Journal of thrombosis and thrombolysis》2018,45(1):151-157
Journal of Thrombosis and Thrombolysis - According to guidelines, it is recommended to give P2Y12 inhibitors (preferably ticagrelor or prasugrel) at the time of first medical contact in patients... 相似文献