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51.
Proportional weight gain and complications of pregnancy, labor, and delivery in healthy women of normal prepregnant stature 总被引:2,自引:0,他引:2
M J Shepard K G Hellenbrand M B Bracken 《American journal of obstetrics and gynecology》1986,155(5):947-954
Detailed reproductive information was obtained through interview at early prenatal visits to hospital clinics, private medical groups, or health maintenance organizations for 4186 women delivered at Yale-New Haven Hospital. From these women, 1,396 were selected who had no preexisting chronic disease, were within their normal prepregnant weight for height as determined by Quetelet's Index (weight2/height2), and were delivered of single infants with no major congenital malformations between 37 and 42 weeks. These women were divided into four quartiles according to their proportional weight gain (weight gain/prepregnant weight): quartile 1 = gains less than or equal to 15%; quartile 2 = gains 16% to 25%; quartile 3 = gains 26% to 35%; quartile 4 = gains greater than 35%. Complications of pregnancy, labor, and delivery were recorded within 2 days of delivery. Compared with the women in quartile 2 those in quartile 4 were 3.8 times more likely to develop gestational hypertension and had a fourfold risk of becoming preeclamptic. They were also significantly more likely to require cesarean section. The size of the infant was a significant risk factor for prolonged second stage of labor in primigravid women (greater than 2 hours) but not in multigravid women (greater than 1 hour). Weight gains of more than 35% almost doubled the risk of a prolonged second stage of labor for multigravid women. High proportional gains were not associated with adverse neonatal outcomes. Clinicians should consider proportional weight gain when advising healthy women about weight gain during pregnancy. 相似文献
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Carl F. Shepard Opt.D. 《Clinical & experimental optometry》1943,26(5):214-219
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Proposed Report on the Educational Qualifications of Sanitarians. Committe on Professional Education
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Pugazhendhi Vijayaraman Lai Chow Kok Richard K. Shepard Mark A. Wood Kenneth A. Ellenbogen 《Journal of interventional cardiac electrophysiology》2004,11(2):91-95
BACKGROUND: Pulmonary vein potentials recorded at the ostia of pulmonary veins (PV) are a useful guide for segmental isolation of the PV in patients with atrial fibrillation (AF). Even during coronary sinus pacing at 600 ms, atrial (A) and PV potentials can overlap in 50-60% of patients making the accurate identification of PV potentials very difficult. METHODS: Nineteen patients (M:F 15:4) with paroxysmal AF underwent segmental isolation of one or more PV. Coronary sinus (CS) pacing was performed at cycle lengths of 600/550/500/450/400/350/300 ms and bipolar electrograms were recorded from the 10 or 20 pole Lasso catheter placed at the atrial-PV junction in 27 pulmonary veins. Stimulus (S) to A, S-PVP and A-PVP intervals were measured during CS pacing at the different cycle lengths at sweep speed of 200 mm/sec. RESULTS: During CS pacing at 600 ms the A and PV potentials were significantly overlapped (A-PVP < or = 25 ms) in 15 of 27 (55%) veins. During pacing at 300 ms, the A and PV potentials were significantly separated (A-PVP > or = 25 ms) in 9 of the 15 veins where A and PV potentials overlapped and 21 of all 27 (78%) veins. In two patients pacing at 300 ms was associated with 2:1 conduction block from atrial to PV fascicle. CONCLUSIONS: Coronary sinus pacing at cycle length of 300 ms demonstrated better separation of A and PV potentials compared to pacing at 600 ms. This strategy is easier and less time consuming compared to extrastimuli testing. It also confirms that the electrophysiological properties of PV fascicles are different from that of the adjacent atrial musculature. 相似文献
59.
Concomitant T-cell receptor alpha and delta gene rearrangements in individual T-cell precursors. 总被引:2,自引:0,他引:2 下载免费PDF全文
S D Thompson J Pelkonen J L Hurwitz 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(14):5583-5586
A debate has recently surfaced concerning the degree of precommitment attained by alpha beta and gamma delta T-cell precursors prior to T-cell receptor (TCR) gene rearrangement. It has been suggested that precursors may be precommitted to rearrange either alpha or delta genes, but not both, thus giving rise to alpha beta- and gamma delta-producing T cells, respectively. Alternatively, the precursors may be flexible with regard to potential TCR gene rearrangements. To address this controversy, the gene rearrangements among a group of T-cell hybridomas from fetal, newborn, and early postnatal mouse thymi were examined. Six probes spanning the delta and alpha loci were used in Southern blot analyses to characterize the rearrangements which occurred on homologous chromosomes in each cell. Although homologous chromosomes often rearranged in synchrony within the alpha locus, a number of hybridomas were found which had retained a delta rearrangement on one chromosome and an alpha rearrangement on the second. Results show that a precommitment by T cells to rearrange delta or alpha genes in a mutually exclusive manner is not an absolute feature of mouse thymocyte development. 相似文献
60.
K V Shepard J Faintuch J D Bitran D L Sweet E Robin B Levin 《Cancer treatment reports》1985,69(1):123-124
Twenty patients with measurable metastatic colorectal carcinoma were treated every 3 weeks with cisplatin (100 mg/m2 iv) on Day 1 and 5-FU (1000 mg/m2/day by iv infusion over 24 hours) on Days 1-5. Seven patients were previously treated with chemotherapy. The mean performance status for all of the patients was 1.5 (Eastern Cooperative Oncology Group). None of the patients had an objective response to the chemotherapy; 11 patients had stable disease and nine had no response. This study demonstrates that the combination of cisplatin and 5-FU, administered at this dose and schedule, has minimal activity in patients with metastatic colorectal cancer. 相似文献