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61.
Fetal breathing movements and gross fetal body movements were observed before, during, and after maternal hyperoxia induced by inhalation of 50% oxygen in 14 women with normal term pregnancies. Studies were performed with real-time B-scan linear-array ultrasound and were standardized for time of day, maternal nutritional status, postprandial interval, and length of observation. Each study included a 30-minute baseline, followed by 15 minutes of hyperoxia, and 45 minutes of continued monitoring. No significant changes occurred in the mean incidences of fetal breathing movements, gross fetal body movements, the mean breathing rate, or breath interval variability, as analyzed in 5-minute epochs. Maternal PO2, as measured by transcutaneous electrodes, increased to the maximum level after 5 minutes of hyperoxia (155% over control levels). The breathing activity of normal third-trimester fetuses appears to be stimulated maximally in the second and third postprandial hours and cannot be further increased by maternal hyperoxia. This protocol represents a possible clinical strategy for investigating fetuses at risk for intrauterine hypoxia, provided that similar experimental conditions are maintained.  相似文献   
62.
Coexistent squamous cell carcinoma and adenocarcinoma of the uterine cervix   总被引:1,自引:1,他引:1  
The clinical and pathological features of 20 patients with coexistent squamous cell carcinoma and adenocarcinoma of the uterine cervix have been analyzed. Various combinations of in situ and invasive carcinomas were found. Located adjacent to each other and at times intermingling, these lesions probably originated from the subcolumnar reserve cells of the transformation zone. They are early lesions and may be precursors of adenosquamous and mucoepidermoid carcinomas of the cervix. The diagnosis of these double carcinomas depends upon being aware that the two entities may coexist in the same cervix. Treatment is conventional, and the prognosis is not worsened by the presence of the two types of neoplasms.  相似文献   
63.
Many of the substances known to control the secretion of pituitary gonadotropins also modulate the secretion of human chorionic gonadotropin (hCG) by the placenta. In order to study the effect of estrogens and progestins on hCG secretion, term placental explants were cultured in culture media for 144 hours. During the culture period, hCG secretion increased after 48 hours, and a fortyfold increase was observed after 144 hours (p less than 0.001). Compared to concentrations of hCG in control cultures, secretion of hCG was markedly suppressed in the presence of progesterone 2.25 X 10(-5)M (p less than 0.001), a concentration similar to that found in term placental tissue (1.7 +/- 0.2 micrograms/gm of tissue). Suppression of hCG by progesterone occurred in a dose-response manner (r = -0.9100, p less than 0.01). Estradiol, an important steroid modulator of pituitary gonadotropins, did not significantly suppress the secretion of hCG, except in pharmacologic concentrations (10(-4)M), and physiologic concentrations of estradiol had no effect on the suppression of hCG by progesterone. These results suggest that the mechanism by which progesterone suppresses the secretion of hCG differs from the manner in which steroids modulate the secretion of pituitary gonadotropins.  相似文献   
64.
A study was undertaken to determine the effect of route of delivery on plasma colloid osmotic pressure. Plasma colloid osmotic pressure was measured on admission to the hospital and 8 to 24 hours post partum in 72 patients at term with uncomplicated prenatal histories. Thirty-six patients underwent uncomplicated vaginal deliveries (local anesthesia, 18; conduction anesthesia, 18) and 36 patients had cesarean sections (conduction anesthesia, 18; general anesthesia, 18). The mean (+/- SD) intrapartum colloid osmotic pressure of the overall group was 21.0 +/- 2.1 mm Hg, and it declined significantly (p less than 0.01) to 15.4 +/- 2.1 mm Hg post partum. A comparison of the intrapartum and postpartum reductions in colloid osmotic pressure between patients who underwent vaginal delivery and those who underwent cesarean section revealed no significant differences. Furthermore, the mean reductions in colloid osmotic pressure when all four groups were compared by type of anesthesia were not significantly different. Fifteen patients (20.8%) in the study had a postpartum colloid osmotic pressure of less than 13.6 mm Hg, and five (6.9%) had a postpartum colloid pressure of less than 12.5 mm Hg. Our results indicate that, for normal pregnancy, colloid osmotic pressure is uniformly lowered in the post partum and, in some cases, to levels that have been reported to be dangerously low.  相似文献   
65.
Controversy continues to surround the significance of residual endometrial adenocarcinoma in the uterus following radiation therapy. Eighty patients with FIGO stage IA, IB, and II endometrial adenocarcinoma treated by preoperative radiotherapy were studied. No correlation was noted between the histologic grade of the lesion and the stage of disease. The frequency and the site of residual carcinoma were not related to the stage of disease but less-differentiated tumors persisted more frequently than grade I lesions. The modality of preoperative radiotherapy did not affect the frequency of residual tumor. Residual carcinoma within the uterus had no effect on the site or frequency of recurrence nor on patient survival.  相似文献   
66.
Apgar scores and umbilical arterial pH in preterm newborn infants   总被引:1,自引:0,他引:1  
One- and five-minute Apgar scores and umbilical cord arterial pH values were compared in preterm newborn infants of various gestational ages. The more premature the infant, the more likely the Apgar score was low in the presence of a pH greater than or equal to 7.25. Conversely, the closer to term, the more frequently an infant with a pH of less than 7.25 had an Apgar score of greater than or equal to 7. Therefore, in preterm infants, there is little congruity between the Apgar score and umbilical cord pH. Based on these findings, it is not appropriate to label preterm newborn infants as asphyxiated based on a low Apgar score.  相似文献   
67.
68.
Peritoneal fluid was collected from 107 women undergoing laparoscopic sterilization or diagnostic laparoscopy for evaluation of infertility. Cells consisting mainly of macrophages were separated and subjected to sophisticated flow fluorocytometric analysis. In this way more detailed information was obtained about activational characteristics of the pelvic macrophage population during the menstrual cycle. In normal women the macrophages, as compared to peripheral monocytes, showed evidence of elevated baseline activation, and a gradual increase in several markers occurred during the menstrual cycle. Cells increased in size, lost their ability to stain for myeloperoxidase, and increased in activity of both endoenzymes and ectoenzymes. These results suggest that female peritoneal macrophages are continuously responding to stimuli. The macrophage irritation was much more pronounced in women with mild endometriosis. This accentuated cyclic activation may represent an inflammatory response to bleeding from ectopic implants or retrograde menstruation or may be a consequence of some defect in the cell-mediated immune response in endometriosis.  相似文献   
69.
A collection of neurological signs and symptoms, entitled abdominal pelvic pain syndrome, is identified as the most common cause of chronic pelvic pain. Techniques to identify abdominal wall, vaginal, and sacral components are described, with painful tissues commonly limited to a single dermatomic area. Superficial local areas of hyperpathia (trigger points) appeared not only to cause the pelvic pain but also to be responsive to local anesthetics for a duration in excess of the presence of the medication. Successful responses were noted in 89.3% of 131 patients, with 92.6% requiring five or fewer treatments and 68.2% followed up for longer than 6 months. The diagnosis of the abdominal pelvic pain syndrome is an important component in avoiding unnecessary operation in patients with pelvic pain.  相似文献   
70.
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