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Follicles > or = 5 mm were ablated in pony mares by a transvaginal ultrasound-guided technique on Day 10 (ovulation = Day 0). Follicle emergence (at 15 mm, experiment 1; at 6 mm, experiment 2) and development of the new wave was monitored by transrectal ultrasound. Deviation was defined as the beginning of a marked difference in growth rates between the two largest follicles. In experiment 1, mares were grouped (n = 4 per group) into controls, ablation-controls (ablations at Day 10 only), and a two-follicle model (periodic ablation sessions so that only the two largest follicles developed). There were no significant indications that the two-follicle model altered follicle diameters, growth rates, or time intervals of the two retained follicles at or between events (follicle emergence, deviation, and ovulation). In experiment 2, the two-follicle model (n = 14) was used for follicle and hormonal characterization and hypothesis testing, without the tedious and error-prone necessity for tracking many (e.g., 20) individual follicles. The future dominant follicle emerged a mean of 1 day earlier (p < 0.008) than the future subordinate follicle, the growth rates for the two follicles between emergence and deviation (6 days later) did not differ, and the dominant follicle was larger at the beginning of deviation (23.1 +/- 0.8 mm versus 19.6 +/- 0.9 mm; p < 0.0001). Mean FSH and LH concentrations increased (p < 0.05) concomitantly from emergence of the future dominant follicle and peaked 3 days later when the follicle was a mean of 13 mm. Thereafter, the two hormones disassociated until ovulation: FSH decreased and LH increased. Results supported the hypothesis that the future dominant follicle has an early size advantage over future subordinate follicles and indicated that the advantage was present as early as 6 days before deviation. 相似文献
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Prognostic classification for esophageal atresia and tracheoesophageal fistula: Waterston versus Montreal 总被引:1,自引:0,他引:1
S Teich DP Barton ME Ginn-Pease DR King 《Canadian Metallurgical Quarterly》1997,32(7):1075-9; discussion 1079-80
Since 1962, the Waterston classification has been used to stratify neonates who have esophageal atresia (EA) and/or tracheoesophageal fistula (TEF) into prognostic categories based on birth weight, the presence of pneumonia, and the identification of other congenital anomalies. In response to advances in neonatal care, the surgeons from the Montreal Children's Hospital proposed a new categorization system in 1993 in an attempt to define the current risk factors for patients who have EA/TEF. In the Montreal experience only two characteristics independently affected survival: preoperative ventilator dependence and associated major anomalies. The goal of this study was to determine which system had the greatest validity for the evaluation of prognosis in our patients with EA/TEF. The charts of 94 patients who had EA/TEF treated between 1972 and 1991 were reviewed. Patients were classified using both the Waterston and Montreal systems. Groups were compared with Fisher's Exact test using a 95% confidence level for statistical significance. Eleven infants were ventilator dependent preoperatively; 62 children had major associated anomalies, 8 of which were considered life threatening. Sixteen children died within 4 years, eight during their initial hospital stay. Five of the eight early postoperative deaths occurred in the highest-risk patients (Waterston C or Montreal II). Analysis was performed for multiple risk factors and mortality. As in the Montreal study, the presence of life-threatening and major congenital anomalies represented significant risk factors for death. Pulmonary disease as delineated by ventilator dependence appeared to be more accurate than pneumonia. This study confirms the accuracy of the Montreal classification in defining prognosis for EA/TEF. The Montreal system more accurately identifies children at highest risk than the Waterston classification. 相似文献
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BACKGROUND: Chylothorax is a rare primary or secondary condition the optimum management of which remains uncertain. METHODS: Twenty cases of chylothorax, including ten of primary chylothorax and ten secondary to either malignancy, subclavian vein thrombosis or lymphangioma treated between 1956 and 1986 have been reviewed. RESULTS: Open pleurectomy was the most successful treatment in preventing reaccumulation of the effusion. Three patients had thoracic duct-azygous vein anastomoses, but all anastomoses were probably occluded within a year of surgery. Three patients have been lost to follow-up and five died within 2 years of their treatment, but 12 patients were alive and free from an effusion 3-22 years after treatment. CONCLUSION: Patients with chylothorax should undergo lymphangiography to identify the cause and site of the lymphatic abnormality. Conservative treatment is successful in some patients but should be abandoned if the fluid loss exceeds 1.5 l/day for more than 5-7 days in an adult or more than 100 ml/day in a child. Parietal pleurectomy is the most successful treatment when no distinct chylous leak can be identified. Less commonly, an isolated chylous leak either in the chest or in the abdomen may be identified and this should be treated by direct ligation. 相似文献
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PR Burchat GJ Feldman T Barklow AM Boyarski DL Burke JM Dorfan L Gladney G Hanson K Hayes RJ Hollebeek WR Innes JA Jaros D Karlen AJ Lankford RR Larsen BW LeClaire NS Lockyer V Lüth C Matteuzzi RA Ong ML Perl B Richter K Riles MC Ross JM Yelton C Zaiser GS Abrams D Amidei AR Baden J Boyer F Butler G Gidal MS Gold G Goldhaber L Golding J Haggerty D Herrup I Juricic JA Kadyk ME Nelson PC Rowson H Schellman WB Schmidke PD Sheldon GH Trilling de la Vaissiere C DR Wood ME Levi T Schaad 《Canadian Metallurgical Quarterly》1987,35(1):27-41
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CA Millar LC Campbell DL Cope DR Melvin KA Powell GW Gould 《Canadian Metallurgical Quarterly》1997,25(3):974-977
The available data suggest that GLUT4 does populate the recycling endosomal system to some extent, but that a large proportion of the intracellular GLUT4 resides in a compartment that is devoid of transferrin receptors and may have properties more akin to specialized secretory vesicles. The study of the nature and biogenesis of this compartment will provide important insight into the mechanism by which insulin stimulates glucose transport. Further study of the role of the synaptobrevins in these distinct subcellular compartments will probably shed further light on the mechanism by which insulin stimulates GLUT4 translocation. 相似文献