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11.
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   

12.
The purpose of this paper is to carry out an analysis of the term leukoplakia since its introduction in 1877 and to expose the most accepted concepts and present classification within specialists. For this purpose attention will be paid to definitions established in the international seminary developed in Malm? City, Sweden, in June 1983. A group of observations on present status of research and diagnostic methods and its limitations to pre-establish when a lesion of this type is going to evolve toward malignancy, is included. An important part of this paper is devoted to the linguistic analysis of leukoplakia and leukoplasia expressions. An extensive argumentation demonstrating the systematic impropriety in the Spanish Language of translating the English term "leukoplakia as leukoplasia, is presented. There is in Spanish the accurate translation, given by the expression leukoplakia, which is not only the adequate one for the exactness of its translation but also the one more conceptually adjusted to contemporary definition universally accepted, that is to say, a white plaque. Finally, a comment on importance of incorporates to our language the exact translation of scientific words, not only to fit it to present science, but also to a better fulfillment of its function in allowing the communication within Latin American researches themselves and with the world scientific community, is exposed.  相似文献   
13.
The R337H TP53 mutation is a low-penetrance molecular defect that predisposes to adrenocortical tumour (ACT) formation in Brazilian and possibly other populations. Additional genetic defects may be responsible for the variable expression of ACTs in these cases. The inhibin α-subunit gene (INHA) on 2q33-qter has been implicated in mouse adrenocortical tumourigenesis. We studied 46 pediatric patients with ACTs from Brazil for INHA genetic alterations; 39 of these patients were heterozygous carriers of the R337H TP53 mutation. We first mapped the INHA gene by radiation hybrid analysis and determined 10 linked microsatellite markers in an area flanked by D2S1371 and D2S206 on 2q33-qter. These markers were then used for loss of heterozygozity (LOH) studies in nine paired germline and tumour DNA samples. Mapping placed the INHA gene in close proximity to D2S2848 (SHGC11864) with a log of odds (LOD) score of 5.84. LOH for at least one marker in the region was identified in 8/9 tumours (89%). Six patients were heterozygous for three INHA mutations: one in exon 1, 127C>G, and two in exon 2, 3998G>A and 4088G>A, all leading to amino acid substitutions (P43A, G227R, and A257T, respectively). A257T is located in a conserved INHA region, highly homologous to transforming growth factor-ß; both G227R and A257T change polarity, and, in addition, G227R changes the pH. We conclude that these sequence alterations and the detected 2q allelic changes suggest that INHA may be one of the contributing factors needed for ACT formation in pediatric patient carriers of the R337H TP53 mutation.  相似文献   
14.
Ultrastructural features of the rat parathyroid (PT) glands have been studied under 3 different glutaraldehyde fixation methods. Cell differences caused by fixation or due to functional conditions were evaluated. The changes of organelles and relationship of plasma membranes of chief dark-light cells, as well the pericapillary and intercellular spaces were used for this evaluation. Light cells were observed in all PT glands studied. PT glands adequately perfused presented light chief cells as transitional secretory form. Incompletely-perfused and immersion-fixed glands presented most of light chief cells as a fixation artifact. The same interpretation was given to intercellular spaces which appeared only in glands fixed by immersion. In adequately perfused glands interdigitated and straight plasma membranes of neighbour chief cells were tightly continuous with frequent desmosomes. Distended mitochondria, RER and Golgi cisternae as well vacuolizations of chief cell cytoplasm and connective tissue were characteristics of unadequately perfused glands. The best fixation method for a homogeneous preservation of all components of rat PT glands, which decreased the possibility of a wrong interpretation of normal variations, was perfusion through the left ventricle. Fixative with pH and osmolarity carefully controlled were injected after saline washing of the vascular bed.  相似文献   
15.
The predictive value of a comprehensive model with personality characteristics, stressor related cognitions, coping and social support was tested in a sample of 187 nonpregnant women. The emotional response to the unsuccessful treatment was predicted out of vulnerability factors assessed before the start of the treatment. The results indicated the importance of neuroticism as a vulnerability factor in emotional response to a severe stressor. They also underlined the importance of helplessness and marital dissatisfaction as additional risk factors, and acceptance and perceived social support as additional protective factors, in the development of anxiety and depression after a failed fertility treatment. From clinical point of view, these results suggest fertility-related cognitions and social support should receive attention when counselling women undergoing IVF or ICSI treatment.  相似文献   
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17.
Adenocarcinoma of the esophagus, or GEJ, has a poor prognosis. Early lesions [i.e. high grade dysplasia (HGD) or T1-carcinoma] are potentially curable. Local endoscopic therapies are promising treatment options for superficial lesions; however, for deeper lesions, surgical resection is considered to be the treatment of choice. To contribute to therapeutic decision-making, we retrospectively analysed the outcome of transhiatal esophagectomy in 120 patients with pathologically proven HGD (n=13) or T1-adenocarcinoma (n=107) of the distal esophagus or gastro-esophageal junction (GEJ). Tumors were subdivided into six different depths of invasion (T1-mucosal m1-m3, T1-submucosal sm1-sm3), and the frequency of lymphatic dissemination and time to locoregional and/or distant recurrence were analysed. Only one of the 79 T1m1-3/sm1 tumors (1%) showed lymph node metastases as compared with 18 out of 41 T1sm2-3 tumors (44%). There was a significant difference in recurrence-free period between T1m1-m3/sm1 versus T1sm2-sm3 tumor patients (P log rank <0.0001), with 5-year recurrence-free percentages of 97% and 57%, respectively. In multivariate analysis including age, gender, tumor differentiation grade, N-stage and depth of invasion, only N-stage was an independent prognostic factor for recurrence-free period (hazard rate=5.9, 95% CI 1.7–20.7). However, if N-stage was excluded from analysis, only depth of invasion (T1sm2-3 versus T1m1-m3/sm1) was an independent prognostic factor for recurrence-free period (hazard rate=7.5, 95% CI 2.0–27.7). These data indicate that T1m1-m3/sm1 adenocarcinomas of esophagus or GEJ show a very low risk of lymphatic dissemination and are therefore eligible for local endoscopic therapy. After transhiatal surgical resection, almost half of the patients with T1sm2-sm3 lesions develop recurrent disease within 5 years, and therefore need additional therapy to improve survival.  相似文献   
18.
19.
Plasma corticosteroid circadian periodicity was determined in three groups of individual adult male rats. Categories were: postsubdiaphragmatic vagotomy, sham-operated, and controls. Blood was sampled every 4 hours over a 48-hour period with ad lib feeding and after a 13-day period on daytime (0930–1330) restriction of food and water availability. Plasma corticosterone circadian periodicity was normal under ad lib conditions in control, sham-operated, and vagotomized animals. Under food-restricted conditions, both the sham-operated and vagotomized animals exhibited the 12-hour shift in the circadian peak of plasma corticosterone levels that we have previously described in normal animals under such conditions. There were no differences between groups in the total amount of food and water consumed or the percentage of nocturnal food intake on an ad lib feeding schedule. Both vagotomized and sham-operated animals manifested reductions in food intake under conditions of food restriction, although vagotomized consumed less than sham-operated animals. The present data indicate that an intact vagus nerve is not necessary for the establishment of circadian periodicity of plasma corticosterone levels or the shift in the periodicity of corticosteroid secretion produced by a restricted feeding regimen.  相似文献   
20.
We investigated the levels of mite allergens (Der p 1, Der f 1, Der 2, and Lep d 1) in dust samples from the homes of 59 patients with asthma, 36 sensitized to house-dust mites (HDM) and 23 to grass pollen (controls), living in Porto, northern Portugal. The relationship between exposure and sensitization to HDM and the influence of housing conditions on mite-allergen levels were also evaluated. Der p 1 (median 9.2 μg/g) and Der 2 (4.6 μg/g) were the main allergens, while Der f 1 and Lep d 1 levels were always <1 μg/g dust and undetectable in 11% and 47% of samples, respectively. All HDM-sensitized asthmatics were exposed to Der p 1 levels >2 μg/g and their homes contained significantly higher levels of Der p 1 (median 12.5 vs 6.4 μg/g; P=0.008) and Der 2 (6.2 vs 3.0 μg/g; P=0.004) when compared to the control group. A significant correlation was observed between the exposure to Der p 1 and the wheal area at skin testing with the Dermatophagoides pteronyssinus (Dp) extract (P=0.01) as well as with serum specific IgE levels to Dp (P=0.03). Patients with higher levels of serum specific IgE (≥17.5 HRU/ml) were also more frequently exposed to Der p 1 levels ≥10 (μg/g (P=0.002). Old homes, presence of carpets, and signs of dampness were conditions associated with significantly higher levels of mite allergens. In conclusion, we found high levels of Der p 1 and Der 2 particularly in the homes of HDM-sensitized patients and we confirm the relationship between exposure and sensitization to HDM, assessed by both in vivo and in vitro methods. In addition to a favorable outdoor climate, we found in our region housing conditions propitious to mite growth, suggesting that specific geographic characteristics must also be taken into account for the correct planning of mite-avoidance measures.  相似文献   
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