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11.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
12.
Intrapulmonary shunt after cardiopulmonary bypass: the use of vital capacity maneuvers versus off-pump coronary artery bypass grafting 总被引:4,自引:0,他引:4
Tschernko EM Bambazek A Wisser W Partik B Jantsch U Kubin K Ehrlich M Klimscha W Grimm M Keznickl FP 《The Journal of thoracic and cardiovascular surgery》2002,124(4):732-738
OBJECTIVES: It has been proved in human subjects and animals that atelectasis is a major cause of intrapulmonary shunting and hypoxemia after cardiopulmonary bypass. Animal studies suggest that shunting can be prevented entirely by a total vital capacity maneuver performed before termination of bypass. This study aimed to test this theory in human subjects and to evaluate possible advantages of off-pump coronary artery bypass grafting. METHODS: Twenty-four patients scheduled for coronary artery bypass grafting were randomly assigned to receive no total vital capacity maneuver (control group, n = 12) or standard total vital capacity maneuvers (TVCM group, n = 12). Additionally, 12 consecutive patients undergoing off-pump coronary artery bypass grafting (off-pump group) were studied. Systemic and central hemodynamics, the pattern of breathing, and ventilatory mechanics were evaluated after induction of anesthesia, after sternotomy, after cardiopulmonary bypass and skin closure, and 4 hours after extubation. RESULTS: The use of total vital capacity maneuvers reduced (P <.05) intrapulmonary shunting after termination of cardiopulmonary bypass. However, shunting increased (P <.05) in all groups (control group, 8.2% +/- 3.3% vs 25.6% +/- 8.1%; TVCM group, 8.7% +/- 3.4% vs 24.4% +/- 8.5%; and off-pump group, 7.8% +/- 2.8% vs 14.0% +/- 5.3%) after extubation, but the increase was significantly (P <.05) less pronounced in the off-pump group. Furthermore, pulmonary compliance decreased (P <.05) in all groups except the off-pump group after extubation. Duration of hospital and intensive care unit stay was significantly shorter (P <.05) in the off-pump group than in the other groups. CONCLUSION: The development of intrapulmonary shunting and hypoxemia after coronary artery bypass grafting can be substantially reduced by performance of total vital capacity maneuvers while patients are mechanically ventilated. However, off-pump coronary artery bypass surgery is superior in preventing shunting and hypoxemia after bypass grafting in the immediate and early postoperative periods, probably leading to substantially shorter intensive care unit and hospital stays. 相似文献
13.
Partik BL Stadler A Schamp S Koller A Voracek M Heinz G Helbich TH 《Investigative radiology》2002,37(9):489-495
RATIONALE AND OBJECTIVES: Comparison of the accuracy of 3D and 2D ultrasound in assessing the volume of human cadaver kidneys. MATERIALS AND METHODS: Before autopsy the volume of 22 kidneys was assessed from a 3D data set after manually tracing organ contours (3D volumetry) and by applying a 3D ellipsoid formula both on a 3D data set and 2D images. Measurements by water-displacement served as the gold standard. RESULTS: 3D volumetry showed a mean absolute deviation of 31 mL (18.5%) compared with the mean gold standard measurement (168 mL), yielding a concordance correlation (Lin's rho(c) ) of 0.71. Calculation based on the ellipsoid formula revealed a mean absolute deviation of 37 mL (22.0%) when applied on the 3D data set (rho(c) = 0.65) and of 42 mL (25.0%) when applied on 2D images (rho(c) = 0.61). CONCLUSIONS: 3D volumetry showed a satisfactory concordance correlation and is superior to volume calculation based on the ellipsoid formula either applied to a 3D data set or to conventional 2D images in assessing the volume of human cadaver kidneys. 相似文献
14.
J Rigo BL Salle E Cavero P Richard G Putet J Senterre 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):127-131
The aim of the study was to compare growth parameters, biochemical indices of protein metabolism and plasma amino acid concentrations in infants fed either human milk ( n = 12) or a whey protein hydrolysate formula ( n = 13) during the first month of life. Growth and gain in skin fold thickness were similar in both groups whereas serum protein concentration was significantly decreased (57.4 ± 3.9 versus 61.2 ± 2.9 g/l) in the infants fed the whey hydrolysate formula. The discrepancies between the plasma amino acid pattern of the whey hydrolysate formula group and that of the human milk group lessened during the first month. Nevertheless, at a mean age of 33 days the plasma threonine concentration remained twice as high and the plasma tyrosine, phenylalanine and proline concentrations were Significantly lower in the whey hydrolysate formula group than in the human milk group. Thus, compared with breast-fed infants, growth and most of the biological indices of protein metabolism were satisfactory in infants fed during the first month of life on a whey protein hydrolysate formula. Nevertheless, the decrease in total plasma protein concentration needs to be confirmed in a larger cohort of infants. In addition, further research is necessary to investigate the possible ways of reducing the hyperthreoninemia and preventing other plasma amino acid disturbances since it would be desirable to obtain plasma amino acid levels similar to those of breast-fed infants. 相似文献
15.
Red blood cell fatty acid composition in low-birth-weight infants fed either human milk or formula during the first months of life 总被引:10,自引:0,他引:10
V Chirouze A Lapillonne G Putet BL Salle 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S405):70-77
The fatty acid composition of red blood cell (RBC) phospholipids in low-birth-weight infants was determined immediately after delivery and during the first 3 months of life. In the first study, infants were fed either human milk or two formulas with different fatty acid compositions but no long chain polyunsaturated fatty acids (LCPUFA). Both groups of formula-fed infants had significantly lower levels of docosahexaenoic acid (DHA) in RBC phospholipids compared with breast-fed infants. RBC phospholipid DHA was similar in the two formula groups at all ages. In the second study, infants received either a non-supplemented or a LCPUFA-supplemented formula. DHA remained stable in RBC phospholipids of infants supplemented with LCPUFA, whereas DHA decreased in RBC phospholipids of unsupplemented infants. These results confirm that adding DHA to formulas is more effective than increasing 18:3 n-3 content, in maintaining RBC phospholipid DHA levels. 相似文献
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Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献