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51.
Ischemic stroke occurs in 0.2-0.4% of patients undergoing left heart catheterization, and is responsible for 5-10% of the mortality associated with the procedure. The main predisposing factors for this complication are female gender, complex atherosclerotic plaques in the ascending aorta, and peripheral arterial disease. The possibility of timely intervention with reperfusion therapy supports close clinical monitoring during the immediate post-catheterization period. The cardiologist should be familiar with the various types of stroke reperfusion therapy and its indications according to the time interval between catheterization and the stroke. The decision should be discussed with neurology and neuroradiology.  相似文献   
52.
The rate of polymerization was described as a function of the monomer concentration of 36 monomer/solvent systems in terms of the reactant-solvent complex (RSC) model. One-, two-and three-parameter optimization procedures were used to fit the rate function to experimental data. Fitting increments were the complex equilibrium constant K and the relative monomer reactivity parameter r11. Irrespective of the optimization procedure, K and r11, were found to correlate with the monomer exponent n and to be K = 0 and r11, = 1 at n = 1. In these cases the RSC model reduces to the classical rate model. Despite the weak character of the monomer (radical)/solvent complexation, this interaction should not be neglected in rate modelling. The RSC model is a convenient tool to describe the chain propagation separately.  相似文献   
53.
We have performed restriction fragment length polymorphism (RFLP) analysis at the low density lipoprotein receptor (LDLR) locus in order to investigate the molecular genetics of familial hypercholesterolemia (FH) in Spain. Firstly, a sample of 50 unrelated patients with a clinical diagnosis of FH was screened for the presence of major rearrangements at this locus by Southern blot analysis of Bgt II digested genomic DNA. Four different mutations were detected, accounting for 8% of the mutant alleles in the Spanish FH sample. Then, we determined the relative allele frequency and estimated linkage disequilibrium between seven RFLPs of the LDLR gene in the remaining 46 FH patients and in 61 normolipidemic controls. Hindi, Avail, Pvu II, Msp I, and Nco I are the most polymorphic sites with individual PIC values higher than 0.28, whereas the Taq I and Stu I sites display low levels of polymorphism. The usefulness of the seven RFLPs to confirm a clinical diagnosis of FH was investigated in 15 FH-families, consisting of 118 individuals, in whom the presence of Familial Defective Apolipoprotein B-100 (FDB) due to the apoB3500 mutation was excluded. Independent haplotypes were constructed for 71 chromosomes: 15 FH and 56 control haplotypes. A total of 14 different haplotypes was found. In 12 families, clinical diagnosis of FH was confirmed by cosegregation analysis, which makes these RFLPs useful for studying the inheritance of the LDLR gene in 80% of Spanish families with FH. Comparison of haplotypes found in the Spanish sample with those found in Swiss and Norwegians suggests heterogeneity of haplotypes among European populations.  相似文献   
54.
As it is not known what changes to leucocyte homeostasis are mandatory for effective adjuvant action, the biological relevance of systemic changes elicited by different vaccine formulations can only be interpreted in the context of the immunological outcomes. We used flow cytometry to quantify the changes in leucocyte subsets induced in mice intradermally immunized with SAMA4 (adjuvant group), outer membrane proteins (OMP) purified from Actinobacillus pleuropneumoniae (OMP antigen group), SAMA4 adjuvanted OMP (OMP vaccine group), or phosphate-buffered saline (PBS: control group). This approach allowed direct comparisons to be made between the effects of antigen, adjuvant or antigen–adjuvant complexes on immune effector cell populations. Antigens complexed with the liposome–iscom hybrid adjuvant, SAMA4, generated strong antibody responses and cytotoxic T-cell activity in animals immunized intradermally, reflecting remobilization and recruitment of specific cell populations. Splenomegaly, due to granulocytosis, monocytosis and megakaryocytosis, was most prominent in the OMP vaccine group. Histological examination of spleen sections confirmed that these changes were due primarily to splenic haematopoiesis. Circulating numbers of granulocytes and monocytes increased significantly (P < 0.05) in the blood of the OMP vaccine group, as did granulocyte numbers in the lungs (P < 0.05). No changes in T- and B-cell numbers were detected by flow cytometry in the spleens, lungs or blood over the 28-day period in any treatment group. Thymocyte numbers (predominantly CD4+CD8+ cells) in the OMP vaccine group fell by 95% within 3 days of immunization. Identical cellular responses were obtained when an innocuous antigen, ovalbumin, was complexed with SAMA4 instead of OMP, thus demonstrating that the adjuvant effects of SAMA4 were due to synergistic interaction between antigen and adjuvant and not due to the presence of toxic components. The association of strong adaptive immune responses with such complex changes in leucocyte homeostasis induced by complexing adjuvant and antigen suggested that the changes were important for effective vaccination and were not purely circumstantial.  相似文献   
55.
M I Torres-Lpez  I Fernandez  L Fontana  A Gil    A Rios 《Gut》1996,38(2):260-264
Intake of thioacetamide in drinking water causes liver cirrhosis in rats, which exhibit many changes similar to human disease. Nucleotides play an important part in major cellular functions, and recent studies suggest that dietary nucleotides may be considered 'semi-essential' nutrients in situations when an inadequate dietary supply may affect the growth of tissues with a rapid turnover rate. The aim of this study was to assess the effect of dietary nucleotides on lesions in thioacetamide-cirrhotic rats, and to calculate the proportion of mono and binucleated hepatocytes in different experimental groups. Rats were given cirrhosis by oral intake of thioacetamide in the drinking water (300 mg/l) for four months. One group was treated with a standard nucleotide free diet, and another group was treated with the same diet supplemented with 250 mg of nucleotides per 100 g of diet for one and two weeks. A striking reduction (mean (SEM)) in the proportion of binucleated cells was seen in thioacetamide-cirrhotic rats (4.8 (1.3) v 21.4 (1.0)), showing a change in the mitotic mechanism in focal lesions. Cirrhotic rats that consumed a semipurified diet supplemented with nucleotides during two weeks showed considerable histological regeneration of the injured liver. These animals had significantly higher proportion of binucleated cells than did animals at the beginning of the recovery period (8.2 (1.2) v 4.8 (1.3)). In the second week of recovery, both types of diet (F = 5.54, p < 0.05) and the previous administration of thioacetamide (F = 142.82, p < 0.001) had significant effects on the percentage of binucleated hepatocytes.  相似文献   
56.
Summary We examined 81 men exposed for a long time to carbon disulphide (CS2) and tested the possible electrocardiographic (ECG) changes of ischemic heart disease (I.H.D.). The subjects were examined twice in two years. In order to make the ECG evaluation more objective, the Minnesota Code was applied. Two obligatory ECG examinations and only one submaximal effort test were carried out. For comparative evaluation, the control group was examined once. We proved that, in spite of the accepted opinion concerning the atheromatous action of CS2, this compound does not cause ECG symptoms of I.H.D. in a higher percentage of exposed persons. It also does not cause any significant increase in I.H.D. symptoms in dynamic ECG observations.  相似文献   
57.
Catecholaminergic pathways in the brain are activated during stress and are presumably involved in the control of physiological and behavioral changes triggered by stress. When repeatedly stressed, adaptive changes have been observed in catecholaminergic activity in the brain. In the present experiment, it was assessed whether or not chronic exposure to immobilization (IMO) altered the influence of catecholamines on behavior in the holeboard and forced swim test by administering alpha-methyl-p-tyrosine (an inhibitor of catecholamine synthesis). Adult Sprague-Dawley rats were used. Chronic stress amortiguated the inhibitory effect of acute IMO on some but not all behaviors in the two tests. Whereas previous chronic IMO exacerbated the effects of the drug on struggling and immobility in the forced swim test, no change in response to the drug as a consequence of chronic IMO was observed in the holeboard test. The present data suggest that chronic IMO-induced changes in the catecholaminergic control of some behaviors might be related to depression-like states in rats. The actual physiological meaning of these changes and the specific receptors involved remain to be elucidated.  相似文献   
58.
OBJECTIVE: The role of surgery in limited SCLC is still a matter of controversy. Even though the response rates to chemotherapy are very high, prognosis of SCLC patients has remained poor with a median survival of only 12-14 months for limited disease. High incidence of local relapses after chemotherapy in limited-stage SCLC led to reassessment of the role of local treatment in the multimodality management of this tumor. METHODS: We performed retrospective comparative analysis of survival in a series of 134 limited-stage SCLC patients treated between 1984 and 1996 with either complete resection followed by chemotherapy (67 patients), or with conventional non-surgical management (67 patients). In all patients who underwent resection, the diagnosis of SCLC was established only postoperatively. The control (non-surgical) group was selected using 'pair-matched case-control' methodology, out of 176 limited-stage patients potentially suitable for surgery (i.e. with no pleural effusion or other local advancement, no supraclavicular lymph node involvement and good performance status), but treated without resection. The major prognostic factors were well balanced between these two groups. Total series included 109 males and 25 females, 20 patients with T1 and 114 patients with T2 disease, 51 N0, 43 N1 and 40 N2 disease. RESULTS: Median survival in patients treated with and without surgery was 22 months and 11 months, respectively, (P < 0.001). The two-year and five-year survival probabilities were 43 and 27%, respectively, in the surgical group, and 17 and 4%, respectively, in the non-surgical group. Subset analysis confirmed significantly longer survival with surgery in all T and N categories, except for N2 disease. Local relapse occurred in 15 and 55% of patients treated with and without surgery, respectively, (P < 0.001). Distant relapse probabilities were similar in both groups (36 and 40%, respectively). The most common site of metastases in the entire series was brain, followed by liver, lymph nodes, bone, lung and skin. CONCLUSIONS: Our results suggest a possible role of surgery in limited-stage SCLC. Thus, a randomised study addressing this issue seems to be justified.  相似文献   
59.
Background. A major concern in evaluating dynamic cardiomyoplasty has been whether the synchronous stimulation of latissimus dorsi muscle is essential for benefit or not. We studied 10 patients to determine the efficacy of the systolic augmentation generated by the synchronous electrical stimulation of the latissimus dorsi muscle.

Methods. Left ventricular ejection fraction, end-systolic and end-diastolic volume indexes, and stroke volume index obtained during resting, peak exercise, and recovery periods (“on” values) were compared with those obtained 1 week after cessation of electrical stimulus (“off” values). Double product and estimated total body oxygen consumption at peak exercise were also calculated and compared.

Results. Higher ejection fractions (0.36 ± 0.07 versus 0.33 ± 0.06 at rest, 0.40 ± 0.07 versus 0.33 ± 0.07 peak exercise, and 0.37 ± 0.06 versus 0.31 ± 0.06 at recovery) and lower end-systolic volume indexes with relatively constant end-diastolic volume indexes were observed with the cardiomyostimulator on. Further, exercise response was better with the cardiomyostimulator on. Double product indirectly reflected better myocardial oxygen supply/demand ratio when on at peak exercise (17 ± 2.2 mm Hg × beats/min × 10−3 for on versus 19 ± 2.6 mm Hg × beats/min × 10−3 for off). Estimated total body oxygen consumption was improved at peak exercise when the cardiomyostimulator was functional (12 ± 2.7 mL · kg−1 · min−1 versus 11 ± 2.6 mL · kg−1 · min−1).

Conclusions. Current data suggest a true systolic assist during synchronous contractions of the latissimus dorsi muscle. It is thought, therefore, that synchronous electrical stimulation is essential for maximum benefit and all the beneficial effect of cardiomyoplasty certainly cannot be attributed to simple wrapping itself.  相似文献   

60.
A prospective, randomized trial evaluates the effects of two postoperative treatment regimens on survival in 198 adult patients with supratentorial gliomas. All patients were irradiated with 6 000 rads after possibly radical removal of tumors. CCNU administration in the dosis of 100 mg/sq m of body surface every 6–8 weeks following surgery proved to have no significant effect on the survival of patients. The median survival time in patients receiving radiation therapy alone was 61±7 weeks, while in those receiving additional chemotherapy was 56±4 weeks. Tumor histological malignancy and patients age were found to be the only important prognostic factors, irrespective of the treatment modality. Address for offprints: T Trojanowski, Department of Neurosurgery, Medical School, Jaczewskiego 8, 20-950 Lublin, Poland  相似文献   
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