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41.
42.
Background: Restoration of spontaneous circulation after cardiopulmonary resuscitation in cardiac arrest patients does not always signal a completely successful outcome. Functional deficiencies of the nervous system are found in many survivors of cardiac arrest. Objectives: To study the effects of dopamine-induced elevated blood pressure on the hemodynamics, oxygen metabolism, and cerebral resuscitation in different perfusion conditions in a resuscitated animal model. Methods: There were 18 pigs included in the study. Ventricular fibrillation (VF) was induced with a programmed electrical stimulation device. After 4 min of untreated ventricular fibrillation followed by 9 min of CPR, 12 animals were resuscitated successfully, and were then randomly assigned to either the study group (dopamine group) or the control group (normal perfusion group). All animals in the two groups received normal saline through continuous intravenous guttae for 4 h at a rate of 15 mL/kg/h. In the study group, dopamine was added to raise the animals' blood pressure. Four hours of intensive monitoring was performed for all study animals. Finally, 24-h evaluation of neurological function was conducted in surviving animals in accordance with the standard of the Cerebral Performance Category Score. Results: In animals in the dopamine group, the cardiac output, mean aortic pressure, coronary perfusion pressure, oxygen delivery, and oxygen consumption were higher than those found in the animals in the normal perfusion group (p < 0.05). Oxygen metabolism was remarkably improved in animals in the dopamine group. Furthermore, cerebral perfusion was better in the dopamine group than in the control group and thus, results of the evaluation of nervous system function were better in animals treated with dopamine (p < 0.05). Conclusions: Dopamine improved systemic perfusion, cerebral blood supply, and oxygen metabolism after successful resuscitation from VF in a porcine model. All of these factors have profound effects on the cerebral resuscitation.  相似文献   
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Epstein-Barr virus lymphoproliferation after bone marrow transplantation   总被引:16,自引:7,他引:16  
We review 15 cases of secondary B-cell lymphoproliferative disorders that occurred among 2,475 patients who received allogeneic bone marrow transplants (BMTs) at the Fred Hutchinson Cancer Research Center (Seattle) between 1969 and 1987. The histopathologic findings in 14 of the 15 patients spanned a wide spectrum of lymphoproliferative lesions. One patient had features characteristic of angioimmunoblastic lymphadenopathy. Epstein-Barr virus (EBV) genomic sequences were identified by Southern blot analysis in each of the 13 patients evaluated. Ten of the 12 lesions evaluated originated in donor cells. In two patients, who had mixed chimerism after transplantation, the lesions originated in host cells. The combined evidence from immunoglobulin light chain staining and the analysis of immunoglobulin heavy chain gene rearrangement indicated that the lesions in most patients represented polyclonal proliferations that gave rise to clonal subpopulations. The results indicate an overall actuarial incidence of 0.6% for this complication in BMT recipients. Anti-CD3 monoclonal antibody (MoAb) treatment of acute graft-v-host disease (GVHD) and T cell depletion of the donor marrow were statistically significant risk factors, and GVHD appeared to play a contributing role, particularly in the setting of human leukocyte antigen (HLA) disparity. Two patients had no identifiable risk factors. Prophylaxis or treatment with acyclovir had no detectable effect in the patients; all but two died with uncontrolled lymphoproliferation.  相似文献   
45.
Fifty-two of 175 (30%) survivors of allogeneic marrow transplantation developed chronic graft-versus-hose diseases (GVHD). Five with limited chronic GVHD had an indolent clinical course with involvement of only the skin and liver. Forty-seven with extensive chronic GVHD had an unfavorable multiorgan disorder that resembled several autoimmune diseases. Thirteen patients with extensive disease (group I) were not treated and only 2 survive with Karnofsky scores >- 70%. Mortality resulted from infections and morbidity from sica syndrome, pulmonary and hepatic insufficiency, scleroderma-like skin disease, and contractures. Another 13 (group II) received a median of 8 mo prednisone and/or a brief course of antithymocyte globulin, and 3 survive without disability. The other 21 (group III) were treated with a combination of prednisone (1.0 mg/kg/q.o.d.) and either cyclophosphamide, procarbazine, or azathioprine (all 1.5 mg/kg/day) for a median of 13 mo. Combination therapy was well tolerated with only modest myelotoxicity. Fifteen in group III had a good and 4 a fair response to treatment while 2 with no response died. Azathioprine and prednisone was the most effective regimen. All therapy has been discontinued in 12 group III patients: GVHD returned in 5 (including 2 who died in spite of retreatment) while 7 remain free of GVHD for a median of 11 (range 6-30) mo observation. Only I group III survivor is disabled and 16 of the original 21 are alive 2-4 yr after transplant with Karnofsky scores of 70%-100%. Thus, combination immmunosuppression appears to favorably affect and, in some cases, premanently arrest the adverse natural course of extensive chronic GVHD.  相似文献   
46.
The evaluation of gastrointestinal function in diabetic patients   总被引:2,自引:0,他引:2  
Nowadays,anumberofoptionsareavailablefortheasesmentofgastricmotorfunction.Thus,aglobalevaluationofgastricmotorfunctionmaybeob...  相似文献   
47.
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD.  相似文献   
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49.
Tuberous sclerosis is an autosomal dominant trait in which the dysregulation of cellular proliferation and differentiation results in the development of hamartomatous growths in many organs. The TSC2 gene is one of two genes determining tuberous sclerosis. Inactivating germline mutations of TSC2 in patients with tuberous sclerosis and somatic loss of heterozygosity at the TSC2 locus in the associated hamartomas indicate that TSC2 functions as a tumour suppressor gene and that loss of function is critical to expression of the tuberous sclerosis phenotype. The TSC2 product, tuberin, has a region of homology with the GTPase activating protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in vitro. Here we show that the region of homology between tuberin and human rap1GAP and the murine GAP mSpa1 is more extensive than previously reported and spans approximately 160 amino acid residues encoded within exons 34-38 of the TSC2 gene. Single strand conformation polymorphism analysis of these exons in 173 unrelated patients with tuberous sclerosis and direct sequencing of variant conformers together with study of additional family members enabled characterisation of disease associated mutations in 14 cases. Missense mutations, which occurred in exons 36, 37 and 38 were identified in eight cases, four of whom shared the same recurrent change P1675L. Each of the five different missense mutations identified was shown to occur de novo in at least one sporadic case of tuberous sclerosis. The high proportion of missense mutations detected in the region of the TSC2 gene encoding the GAP-related domain supports its key role in the regulation of cellular growth.   相似文献   
50.
The present study was undertaken to evaluate the dimensions of the laminas from C2 to L5 by using adult human spine specimens for the objective of providing a set of quantitative data for the laminas from C2 to L5 vertebrae.There exists enormous amount of Anatomic data based on facet and pedicle parameters by different research workers, but it seems that the detailed studies based on measurements of laminar parameters from cervical to lumbar spines are almost nil.Forty spines (920 vertebrae) were considered for the present study. Anatomic evaluation of the laminas'included the laminar height, width, thickness, width angle & slope angle.The greatest laminar height was observed at T11 for males & females ( 22.8 ± 2.1 mm, 23.0 + 1.8mm) respectively. There was a marked change in pattern at L5 where there was a decrease in laminar height from that of preceding lumbar levels.The greatest laminar width was at-L5 for males & females (12.1 ± 2.4mm 11.5 ± 2.1 mm ) respectively. The laminar thickness was maximum at T3 for males and females (5:2 ± 0.7mm & 5.1 ± 0.2mm ) respectively. The maximum width angle was at T9 for males (99.2 ± 9.7mm) & at L4for females (100.6 ± 12.3mm). The-slope angle was maximum at L5 for males and females (113.5 ± 4.8mm & 118.0 ± 1.4mm) respectively.Thus, for the proper, understanding of the weight transmission through the spine and it related hypothesis the Anatomic parameters of the laminas provided by the present study are very important and also they provide an adequate database necessary for the surgical placement of sublaminar instruments in spine related surgeries.  相似文献   
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