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1.
An unusual case of chylothorax is described in a 4-year-old child after repair of a ventricular septal defect and ligation of a patent ductus arteriosus through a median sternotomy. Left chylothorax developed after a latent period of six days and was treated initially with continuous drainage and parenteral supplementation of proteins and lipids. Operative intervention with oversewing of the site of the leak in the anterior mediastinum proved necessary after three weeks. The anatomical variations of the thoracic duct are outlined to explain the occurrence of chylothorax after diverse intrathoracic operations. The physiological effects of a thoracic duct fistula and various aspects of management are reviewed. 相似文献
2.
KM Hay 《Canadian Metallurgical Quarterly》1976,26(166):372-376
In many patients with migraine, several localised areas usually on the scalp or neck can be identified. The local injection of lignocaine one per cent and adrenaline 1/200,000 often leads to considerable relief of the symptoms of migraine including visual phenomena. The common sites of the trigger areas are shown and several uncontrolled case reports of the effect of the treatment are described. 相似文献
3.
JW McArthur KM O'Loughlin IZ Beitins L Johnson J Hourihan C Alonso 《Canadian Metallurgical Quarterly》1976,51(10):607-616
Serial endocrine studies were performed during the refeeding of a group of nine young women who presented with amenorrhea associated with injudicious dieting. No significant psychopathology was disclosed by the Lanyon Psychological Screening Inventory in any of the patients, six of whom were single and three married and infertile. The mean weight before refeeding was 81.6% of the normal for height. The mean initial serum follicle-stimulating hormone concentration was within the limits of normal for young women of reproductive age, but the serum luteinizing hormone (LH) concentration and the vaginal maturation score were low. As weight was regained, the serum LH concentration increased (the pooled r for LH versus percent normal weight = 0.85) and the vaginal maturation score rose (the pooled r for vaginal maturation score versus percent normal weight = 0.93). When a mean weight of 96.6% of normal was reached after a mean of 5.3 (range, 2 to 11) months of refeeding, spontaneous menses occurred. The initial cycle was ovulatory in two instances and anovulatory in five, as determined by basal body temperature patterns, plasma progesterone concentrations, and endometrial biopsies. With continued weight gain, menstruation became regular and the three married patients conceived. 相似文献
4.
KM Ebert 《Canadian Metallurgical Quarterly》1998,42(7):1003-1008
Conformational effects and affinities of VP-16 (etoposide) and its derivatives to DNA in the presence of Cu(II) ion were examined by circular dichroic (CD) spectra. The Cu(II)/Cu(I) redox kinetics and the hydroxyl radical (.OH) generation from the Cu(II)-complexes were estimated by the stopped-flow kinetics. Based on the results, DNA-cleaving activity of Cu(II)-complexes of VP-16 has been shown to be related with binding affinity of the complex to DNA, Cu(II)/Cu(I) redox and .OH generation, emphasising the mechanism of generated .OH attack to DNA. 相似文献
5.
KM Shokat 《Canadian Metallurgical Quarterly》1995,2(8):509-514
Cytoplasmic tyrosine kinases are composed of modular domains; one (SH1) has catalytic activity, the other two (SH2 and SH3) do not. Kinase specificity is largely determined by the binding preferences of the SH2 domain. Attaching the SH1 domain to a new SH2 domain, via protein-protein association or mutation, can thus dramatically change kinase function. 相似文献
6.
7.
HK Kinyamu JC Gallagher JM Prahl HF DeLuca KM Petranick SJ Lanspa 《Canadian Metallurgical Quarterly》1997,12(6):922-928
This paper systematically reviews the results from epidemiologic studies investigating the hypothesis that breast cancer risk in postmenopausal women increases with increasing concentrations of estradiol in blood and with increasing urinary estrogen excretion rates. Data from 29 epidemiologic studies of endogenous hormones and postmenopausal breast cancer were used. The ratio of the average estrogen concentration in the women with breast cancer to that in the women without breast cancer (and its 95 percent confidence interval [CI]) was calculated for each study, and the results were summarized by calculating weighted averages of the log ratios. In six prospective studies of serum estradiol concentration, 329 women who subsequently developed breast cancer had, overall, a 15 percent (CI = 6-24 percent, P = 0.0003) higher mean concentration of estradiol in their blood than the 1,105 women who remained free of cancer. The results of these prospective studies did not differ significantly from each other (chi2 for heterogeneity = 8.7; degrees of freedom = 5; P > 0.1). Similar differences in mean estrogen levels were seen in the case-control studies which reported either estradiol concentrations in the blood or urinary estrogen excretion. However, the case-control studies showed significant heterogeneity among their results. The data from the prospective studies strongly suggest that breast cancer risk in postmenopausal women is associated with relatively high concentrations of endogenous estradiol. 相似文献
8.
1. During independent finger movements, the intrinsic muscles of the hand show a fractionated pattern of activity in which the timing and amplitude of electromyographic (EMG) activity varies considerably from one muscle to another. It has been suggested that, in the macaque monkey, corticomotoneuronal (CM) cells that produce postspike facilitation (PSF) of EMG in these muscles contribute to this fractionation. To test this hypothesis, we have investigated the relationship between the pattern of PSF exerted by a CM cell and the pattern of activity shown by the cell and by its target muscles. 2. The activity of 15 identified CM cells was recorded from two monkeys that performed a precision grip task. Spike-triggered averaging of rectified EMG during the hold period of this task showed that each cell produced PSF in at least two intrinsic hand muscles. 3. Segments of data were selected from the initial movement period of the task in which the EMG activity in one target muscle was substantially greater than that of the other, and the mean firing rate of each CM cell was determined for these periods. 4. CM cells showed bursts of activity in the movement period. Most of them (13/15) had a significantly (P < 0.001) higher firing rate when one of its target muscles was more active than the other. For nine of these cells (identified as set A), this muscle was the one receiving the larger PSF. In four cases (set B), the reverse was true. Two cells (set C), which produced PSF of equal size in their target muscles, showed no change in firing rate across the periods of fractionated EMG activity. 5. All set A and set B cells fired at significantly (P < 0.001) higher rates during the movement period, in association with fractionation of EMG activity, than in the hold period, in which a cocontracted pattern of muscle activity was observed. 6. There were pronounced differences in the strength of PSF exerted by the CM cells on their target muscles during the fractionation periods. One CM cell exerted PSF of a muscle during one period of fractionation, but postspike suppression of the same muscle during the other period. 7. It is suggested that changes in the firing rate of a CM cell and in the degree of facilitation it exerts could both contribute to the fractionation of activity in its target muscles. Cells of set A appear to be specifically recruited in a manner that directly reflects the pattern of facilitation they exert on the sampled target muscles. These results may explain why the CM system is so important for the performance of relatively independent finger movements. 相似文献
9.
JW Cohen AC Monheit KM Beauregard SB Cohen DC Lefkowitz DE Potter JP Sommers AK Taylor RH Arnett 《Canadian Metallurgical Quarterly》1996,33(4):373-389
This article describes the Medical Expenditure Panel Survey (MEPS), the third in a series of nationally representative surveys of medical care use and expenditures sponsored by the Agency for Health Care Policy and Research. The MEPS is designed to provide extensive data on the types of health care services American use, how frequently they use them, how much is paid for the services, and who pays for them. It also will provide information on the types and costs of private health insurance available to the U.S. population. The survey is unparalleled in its degree of detail, as well as its ability to link medical care use, payments, and health insurance coverage to specific survey respondents and their families. It allows analysts to examine how individual and family characteristics, including the characteristics of their health insurance, affect medical care use and spending. This article discusses each of the MEPS components, focusing on design enhancements that have been made since the survey was last conducted nearly a decade ago. 相似文献
10.
ED Engelstein KM Stein SM Markowitz BB Lerman 《Canadian Metallurgical Quarterly》1996,27(5):1098-1105
OBJECTIVES: This study sought to present evidence that fast atrioventricular (AV) node pathways with posterior exit sites may participate in typical AV node reentry. BACKGROUND: Catheter ablation of the slow AV node pathway in the posteroseptal right atrium is the preferred therapeutic approach in patients with AV node reentrant tachycardia. Despite the success achieved with this approach, electrophysiologic changes consistent with fast pathway ablation are occasionally observed. One potential explanation is the presence of an aberrant posterior fast pathway. METHODS: The location of fast and slow AV node pathways was determined by atrial activation mapping along the tricuspid valve annulus during tachycardia and was further confirmed by the effect of radiofrequency catheter ablation. RESULTS: Seven patients with AV node reentrant tachycardia had evidence of a posterior fast pathway near the coronary sinus os. Abolition of anterograde and retrograde fast pathway conduction followed radiofrequency ablation in the posteroseptal region in six patients. Consistent with fast pathway ablation, the AH interval increased from 70 +/- 24 to 195 +/- 35 ms (mean +/- SD), and tachycardia was no longer inducible. Selective slow pathway ablation was performed in one other patient with a posterior fast pathway. CONCLUSIONS: Functionally fast AV node pathways may be located in the posteroseptal right atrium, where slow pathway modification is performed. These data delineate the limitation of an anatomically guided slow pathway ablative approach and emphasize the importance of detailed mapping and localization of the retrograde fast pathway exit site before ablation. Failure to recognize the presence of posterior fast AV node pathways may account for sporadic examples of AV block, complicating posteroseptal ablation in patients with AV node reentry. 相似文献