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991.
RN Beckhardt JG Murray CN Ford JE Grossman JH Brandenburg 《Canadian Metallurgical Quarterly》1994,16(3):232-239
BACKGROUND: The relationship between preoperative pulmonary function tests (PFTs) and postoperative aspiration and deglutition complications in supraglottic laryngectomy (SL) has not been adequately analyzed. The effects of numerous other variables are either controversial or have not been studied. METHODS: A retrospective chart review was performed on 46 SL patients, analyzing preoperative PFTs and arterial blood gases, demographic factors, stage of disease, extended resections, cricopharyngeal myotomy, hyoid preservation, neck dissection, and postoperative radiotherapy with regards to aspiration and deglutition problems. RESULTS: Eighteen (39%) patients had no problems, 15 (33%) had moderate problems, and 13 (28%) had severe problems; of these, 39 (85%) were ultimately successful with no further swallowing dysfunction, whereas seven (15%) suffered intractable aspiration difficulties. Decreasing FEV1/FVC was significantly correlated with a poorer outcome, as was a greater number of pack-years of smoking. The effect of FEV1/FVC was shown to be independent from pack-years, whereas the converse was not clearly demonstrated. Extensions of the standard procedure did not correlate significantly with increased problems. CONCLUSIONS: An FEV1/FVC less than 50% signifies a greater risk for severe aspiration and deglutition complications, although it must be regarded as one factor among many in determining operability. With careful attention to reconstruction, extensions of the standard SL procedure can be safely performed. 相似文献
992.
A preterm boy was born at 34 weeks. Prenatal ultrasonography showed oligohydramnios, fetal ascites, large kidneys, and small thorax. He died 21 h after birth of respiratory insufficiency. Autopsy revealed Potter's-like facies, hypoplastic lungs, ascites, and bilateral nephromegaly (renal weight almost 10 times normal). The kidneys were finely nodular externally, solid, and cerebriform on cut section. Histologically, they showed a diffusely distorted architecture of jumbled lobules, hyperplasia of cortical-type tissue with inconspicuous proximal tubules, relative hypoplasia of medullary tissue, tubulointerstitial dysplasia, and perilobar nephrogenic rests. The renal features represent a variety of the universal or panlobar (also called pancortical or infantile) type of nephroblastomatosis. To our knowledge, this is only the third such case reported. In the brain, each lateral ventricle contained a yellow gelatinous mass. Histologically, the masses consisted of a pseudomyxoid matrix with delicate fibers and focal adipocyte clusters, all confined within choroid plexus. We consider these lesions fibrolipomatous hamartomas. 相似文献
993.
RW Fuller JH Cardellina J Jurek PJ Scheuer B Alvarado-Lindner M McGuire GN Gray JR Steiner J Clardy E Menez 《Canadian Metallurgical Quarterly》1994,37(25):4407-4411
Ten halogenated monoterpenes (2-6 and 8-12) related to the novel antitumor compound halomon (1) or to the carbocyclic analog 7 have been isolated from different geographic collections of the red alga, Portieria hornemannii. Structures were assigned to the basis of spectral analyses (primarily NMR and MS). The absolute configuration of isohalomon (2) was further established by X-ray crystallography. The compounds were comparatively evaluated alongside 1 and 7 in the U.S. National Cancer Institute's in vitro human tumor cell line screening panel. The results provide some interesting initial insights into the structure/activity relationships in this series. 相似文献
994.
The age-dependent loss of the major peripheral nerve lipids (cholesterol, phospholipid, and total galactolipid) was quantitated over a period of 9 weeks of Wallerian degeneration induced by surgical transection of rabbit sciatic nerves in animals of several ages. Proportionate losses of these lipids were determined by calculating the content of each lipid on a per nerve and on a per gram fresh weight basis remaining after a given period of Wallerian degeneration as a percent of original normal values at several time following surgery. The proportionate loss of each lipid from the distal stump was the most prompt and the most complete in nerves transected at 2 weeks of age, and the least in nerves transected at 20 weeks of age. The prompter clearance of these lipids from younger than older degenerating nerve gives convincing evidence that the suggestion from light-microscopic studies of faster clearance of neural debris in younger than in older animals is correct. A possible relationship between these biochemical findings and the phenomenon of greater functional recovery from peripheral nerve injury in younger than in older subjects is discussed. 相似文献
995.
J Miller G Kauffman J Elashoff H Ohashi D Carter JH Meyer 《Canadian Metallurgical Quarterly》1981,241(5):G403-G415
Previous work has indicated that a chemoselective resistance controls gastric emptying. By use of meals of glucose or oleate, which were shown to empty spontaneously from dogs' stomachs half as fast as saline, we sought to locate this resistance by studying flow under controlled pressures in various regions of the gastrointestinal tract. In intact dogs, gastric outflow of glucose or oleate rose one-third as fast as outflow of saline as gastric pressure was raised, and this increased resistance to outflow of nutrients was unaffected by truncal vagotomy and pyloroplasty. In fistula dogs, gastroduodenal outflow rose linearly with gastroduodenal pressure gradients; outflow was markedly inhibited in a dose-related manner by intestinal oleate but not glucose. Inhibition by oleate was abolished by pyloroplasty. Glucose or oleate flowed into the small bowel from a barostat only slightly slower than saline. However, there was a strong inhibition of intestinal inflow of all three meals by gastric distension, an effect unaltered by truncal vagotomy. The findings suggest that gastric emptying is controlled by complex interactions among pressures and resistances, both within and beyond the stomach. 相似文献
996.
H Enright K Daniels DC Arthur KE Dusenbery JH Kersey T Kim WJ Miller NK Ramsay GM Vercellotti DJ Weisdorf PB McGlave 《Canadian Metallurgical Quarterly》1996,17(4):537-542
This article presents health expectancy calculations from Bulgaria for 1976-1992. The calculations are based on mortality statistics and data from a national information system from the Expert Medical Commissions on Working Capacity about loss of working capacity. Following internationally accepted terminology, the most appropriate term for the health expectancies presented here is "occupational handicap-free life expectancy' (OHFLE). Life expectancies were calculated as partial life expectancies from ages 16 to 59. Health expectancy calculations followed Sullivan's cross-sectional method with age and sex specific prevalence data on occupational handicap. Around 1985 a three- to four-fold increase in these prevalences occurred. The distribution of occupational handicaps over sexes, age groups and severity levels, however, remained fairly constant. The results show a decrease both in partial life expectancy within the age range 16-59 and in OHFLE at the age of 16 for men. For women a more or less stable partial life expectancy and a decrease in OHFLE at the age of 16 was found around 1985. The introduction of more incentives for people who successfully registered probably caused the decrease around 1985. Major social changes may have acted as confounding factors for the fluctuations after 1985. On the other hand the findings may reflect real changes in population health due to an increasing incidence in some major disease categories. The nation-wide system for assessment and registration of health related working incapacity has proved a useful source for an attempt to calculate OHFLE. Given uncertainties about the population health underlying these changes in OHFLE, however, it is recommended that health interview and health examination surveys should be considered as alternative routes for achieving a more comprehensive picture of population health in Bulgaria. 相似文献
997.
998.
999.
T Nakatani T Sato BF Trump JH Siegel K Kobayashi 《Canadian Metallurgical Quarterly》1996,196(2):117-126
Meningiomas arise from the arachnoidal cells surrounding the brain and are one of the most common tumors of the central nervous system. These tumors are known to be hormonally modulated and may occur in association with breast carcinoma. Overexpression of the erbB-2 oncogene product and mutation of the tumor suppressor p53 gene are considered causal driving forces in the pathogenesis of adenocarcinomas of the breast. To determine whether abnormal expression of these genes also plays a role in the pathogenesis of meningiomas, we analyzed the expression of the erbB-2 and p53 proteins in 17 atypical and 35 typical meningioma tissue specimens by immunohistochemistry. The staining intensity was assigned a relative value of 0 to 5+, where 5+ denoted confluent immunoreactivity, 4+ to 1+ denoted varying degrees of focal positivity, and 0 denoted no evidence of staining. Levels of p53 and erbB-2 immunohistochemical staining were then correlated with tumor histology. For p53 immunoreactivity, typical meningiomas had a median staining score of 1.0, compared to 4.0 for atypical meningiomas (P < 0.0001, Mann-Whitney U test). For erbB-2 immunoreactivity, typical meningiomas had a median staining score of 5.0 compared to 1.0 for atypical meningiomas (P < 0.0001, Mann-Whitney U test). The inverse relationship between levels of erbB-2 and p53 immunoreactivity was found to be statistically significant (P < 0.0001, ANOVA). Expression of the erbB-2 protein was not associated with gene amplification or the presence of activating mutation in the transmembrane region of the protein. These findings may improve our understanding of the molecular events that occur in the neoplastic transformation of meningothelial cells. The patterns of erB-2 and p53 immunoreactivity may prove to be useful markers with which to identify potentially more malignant meningiomas. 相似文献
1000.