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991.
Maternal and perinatal morbidity resulting from placenta previa 总被引:1,自引:0,他引:1
One hundred forty-seven cases of partial or complete placenta previa from 1975 to 1982 were reviewed. A history of prior cesarean section was associated with a significant increase in maternal morbidity, including massive hemorrhage, placenta accreta, and hysterectomy. Despite tocolysis and transfusions to delay delivery, nearly two-thirds of the patients were delivered before 36 weeks' gestation. Onset of bleeding before 20 weeks' gestation was associated with a very poor fetal prognosis. The perinatal mortality rate was 81 of 1000. The overall incidence of respiratory distress syndrome was 22%; this was a major cause of neonatal mortality and morbidity. There was a statistically significant correlation between antepartum maternal hemorrhage and the need for neonatal transfusion, and between the neonatal anemia and the amount of intrapartum maternal blood loss. 相似文献
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996.
We compared mean nuclear size and mean nuclear shape (nuclear roundness) on Feulgen-stained smears from 113 cases of prostatic carcinoma analyzed by DynaCELL system at x 100 magnification versus CAS system at x 40 where DNA can be assessed simultaneously. Correlation coefficients were 0.67 for size and -0.07 for shape. A subgroup of cases were compared at x 40 versus x 100 on the CAS system by two observers: The correlation for size ranged 0.47 to 0.49, with correlations for shape ranging from -0.19 to 0.54. In this subgroup at x 100 magnification, the correlation between CAS and DynaCELL was 0.32 for size and 0.07 for shape. At x 100 magnification on the CAS system, intraobserver correlation was 0.58 for size and 0.37 for shape with interobserver correlations of 0.36 for size and -0.05 for shape. At x 40 on the CAS system, intraobserver correlation was 0.42 for size and 0.72 for shape, with interobserver correlations of 0.06 for size and 0.45 for shape. This study shows that in comparison to video planimetry of prostatic cancer nuclei, which has been shown to have a high inter- and intraobserver correlation, the CAS 200 system provided accurate measurements of size yet not shape. Intra- and interobserver correlations were suboptimal with CAS, showing better results at x 100 for size and x 40 for shape. These results in part reflect the relative narrow range of size and shape in prostate cancer in comparison to other tumors, and the use of Feulgen smears where nuclear RNA is not stained or measured by the CAS system, potentially leading to artifactually irregular shapes. 相似文献
997.
The hydrolysis kinetics of 3-quinuclidinyl benzilate were determined over the pH 0-14 range at different temperatures in solutions buffered to a constant pH. Analysis of data extrapolated to zero buffer concentrations permitted construction of an overall rate expression for pH 0-14 and 0-100 degrees. Reaction mechanisms are discussed. 相似文献
998.
Variations in seminal plasma constituents from fertile, subfertile, and vasectomized azoospermic men
Freshly ejaculated semen specimens from 20 normal fertile, 11 subfertile, and 20 vasectomized men whose semen analyses had reached complete azoospermia were compared. The mean levels of seminal acid phosphatase were significantly higher in the vasectomized men. The mean values of sialic acid in normal and postvasectomy seminal plasmas were similar, in contrast to the lower values in oligospermic men. No significant differences were observed in seminal plasma proteins, alkaline phosphatase, and fructose levels. No correlation was found between seminal alkaline phosphatase and fructose levels and sperm concentration. Azoospermia occurring after vas ligation was attributed to high phosphatase values. 相似文献
999.
E Epstein 《Cutis; cutaneous medicine for the practitioner》1979,24(1):104-106
The buried horizontal mattress suture (BHMS) is a new tension suture technique using synthetic absorbable polyglactin 910 suture. When used in minor surgery of the trunk and extremities, this technique eliminates significant suture marking. 相似文献
1000.
The resonance conditions associated with the propagation of a harmonic wave within a rigid, lossless branching structure can
be explicitly derived. In this study, exact resonance conditions are derived for multi-order, rigid, asymmetric branching
structures. These are compared with resonance conditions for rigid, multi-order, symmetric branching structures which we reported
previously. The effect of asymmetry on the form of the higher-order resonance condition is discussed. In the low-frequency
range, the resonance condition can be modified into simpler forms which facilate volume estimation of the branching structure.
Two such volume approximation techniques are presented: (a) a fundamental frequency method, in which the lowest resonance
frequency is inversely proportional to the structure volume, and (b) an effective-length method, in which an effective length
is calculated for all branches distal to the first bifurcation. Equivalence of the two methods is demonstrated. An experimental
study was performed to measure the resonance modes of several second-order glass models with asymmetric branching structures
similar to those of mammalian lungs. The resulting volume estimates were in close agreement with the true volumes. 相似文献