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71.
Judith P. Rooks Norman L. Weatherby Eunice K. M. Ernst 《Journal of Midwifery & Women's Health》1992,37(5):301-313
Part II of a three-part report of the National Birth Center Study describes care provided to 11,814 women and their newborns during and after labor and delivery until they were transferred or discharged from the birth centers. There were few low birth weight or preterm or postterm births, but more macrosomic babies than among all U.S. births during the same time period. Certified nurse-midwives provided most of the intrapartum care, which is described in the context of medically recommended standards and data that describe care provided to low-risk women giving birth in U.S. hospitals. Birth center care deviated from typical hospital care in several ways. Birth center clients were much less likely to receive central nervous system depressants, anesthesia, continuous electronic fetal monitoring, induction and/or augmentation of labor, intravenous infusions, amniotomies, or episiotomies, and they had relatively few vaginal examinations. They were more likely to eat solid food during labor and to take showers and/or baths Nulliparity was strongly associated with longer first stage labors and longer labor was associated with more frequent use of many kinds of interventions. Infant birth weight, mother's position during delivery, and forceps- or vacuum-assisted deliveries are examined in relation to episiotomies and lacerations and tears. 相似文献
72.
The effect of increasing haemoglobin by erythropoietin therapy on exercise capacity was investigated in 11 regular haemodialysis patients, previously transfusion dependent. Exercise work load increased from a median of 100 W (95% confidence limit, 25-135) to 120 (45-180; p < 0.05) following erythropoietin, and the duration of the exercise test from 13 (3.5-20) to 15.5 min (4-22; p < 0.05). Resting blood lactate concentration decreased from 0.8 (0.6-1.6) to 0.3 mmol/l (0.3-0.4), p < 0.05, following treatment with erythropoietin, as did blood lactate concentration at maximal exertion from 2.0 (1.0-4.1) to 1.8 mmol/l (0.5-2.8; p < 0.05). In association with the increase in haemoglobin from a median of 6 (5.1-6.8) to 11.1 g/dl (11-11.9) following erythropoietin therapy, patients were able to achieve greater exercise capacity both in terms of maximum work load and duration of exercise in association with a reduced resting arterial lactate and a similar exercise-induced lactate production. This suggests that treatment had improved muscle function in terms of lactate production and/or utilisation. This was probably due to the increase in tissue oxygen delivery, as there was an increase in the median arterial oxygen content from 79 (65-85) to 150 ml O2 (144-157) following erythropoietin treatment. 相似文献
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Christian Lee Norman Tinanoff Glenn Minah Elaine Romberg 《Journal of public health dentistry》2008,68(1):57-60
OBJECTIVES: Visible plaque on the maxillary anterior teeth of young children has been identified as a risk indicator for early childhood caries. The present study examined whether this plaque is related to the colonization of children's teeth with Mutans streptococci (MS) or toothbrushing frequency. METHODS: Thirty-nine children, aged 12 to 36 months, had plaque scores, and plaque samples were taken from the labial surfaces of the maxillary incisors at baseline and repeated 3 days after suspended oral hygiene (plaque regrowth). RESULTS: A positive correlation was found between the baseline percent MS and regrowth plaque score and between baseline and regrowth plaque scores. Plaque scores of those that brushed zero to one time a day were not different from those who brushed two or more times a day. CONCLUSIONS: This study suggests that the presence of plaque on the anterior teeth of young children is consistent and related to MS colonization. 相似文献
76.
A three-dimensional reconstruction of the intrinsic musculature surrounding the end of the common bile duct in man, generally referred to as the sphincter of Oddi, is presented. Here is visualized grossly for the first time the structure of the muscles in this important region in the adult human. A separate circular sheath of muscle is seen which by contraction can cause the clinical picture known as biliary dyssynergia. The model substantiates in the main and visualizes in three dimensions the findings reported by Hendrickson, Nuboer, Schwegler and Boyden, and Kreilkamp and Boyden. 相似文献
77.
N. A. Lee N. C. Rachaputi G. C. Wright S. Krosch K. Norman J. Anderson 《Food and Agricultural Immunology》2005,16(2):149-163
Analytical validation of a competitive direct SUNQuik ELISA with a reference High Performance Liquid Chromatography (HPLC) method and other methods including a minicolumn method and the VICAM Aflatest® system for aflatoxin in peanuts was conducted. Both the ELISA and the VICAM Aflatest® system, using the same peanut extracts were analytically comparable with the HPLC method (R=0.998, p<0.000). The minicolumn method was also found to be acceptable as a low cost rapid semi-quantitative test. Despite the large variation in sampling, the correlation between the SUNQuik ELISA and HPLC using the different peanut sub-samples was considered acceptable over the range of 0–1200 µg kg?1 (R=0.938). No false negatives were found using the SUNQuik ELISA and false positives were either nil or negligible in all the studies conducted. The repeatability of the SUNQuik ELISA run on the same day was good with only±10% deviation. The reproducibility of the SUNQuik ELISA between days was also acceptable, but with a higher deviation. Applying the SUNQuik ELISA for aflatoxin surveys of peanuts in Indonesia proved that the method can deliver high quality, cost- and time-effective analysis with very little establishment capital and maintenance. 相似文献
78.
Adinarayana Andukuri Will P. Minor Meenakshi Kushwaha Joel M. Anderson Ho-Wook Jun 《Nanomedicine : nanotechnology, biology, and medicine》2010,6(2):289-297
The goal of this study is to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles (PAs) through a solvent evaporation technique. Three PAs, one containing the Tyr-Ile-Gly-Ser-Arg (YIGSR) ligand, the second containing the Val-Ala-Pro-Gly (VAPG) ligand, and a third without cell adhesive ligands, were developed. Cell adhesion and spreading were evaluated by a PicoGreen-DNA assay and live/dead assay, respectively. Our results show that PA-YIGSR significantly enhances HUVEC adhesion (26,704 ± 2708), spreading (84 ± 8%), and proliferation (50 ± 2%) compared with that of other PAs. PA-VAPG and PA-YIGSR showed significantly greater AoSMC adhesion compared with that of PA-S. PA-VAPG also showed significantly greater spreading of AoSMCs (63 ± 11%) compared with that of other PAs. Also, all the PAs showed significantly reduced platelet adhesion compared with that of collagen I (control). These findings would facilitate the development of novel vascular grafts, heart valves, and cell-based therapies for cardiovascular diseases.From the Clinical EditorThe goal of this study was to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles through a solvent evaporation technique. The findings are expected to facilitate the development of novel vascular grafts, heart valves, and cell based therapies for cardiovascular diseases. 相似文献
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