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71.
Acinar epithelial cells were purifed from suspensions of cells from the lactating mammary glands of rats. As described previously, this purififaction was accomplished by sedimentation in an isokinetic gradient of Ficoll (polysucrose) in tissue culture medium, and the purity of the separated cells was established by electron microscopy and by histochemical markers. Isoenzymes of glucose-6-phosphate dehydrogenase were investigated at various intervals during lactation in separated populations of stromal and acinar cells. Acinar cells contained three- to eightfold more glucose-6-phosphate dehydrogenase activity than did stromal cells. The proportions of the respective isoenzymes varied during the course of lactation, and the observed changes were parallel in purified acinar cells and in the lactating mammary glands from which the cell suspensions were obtained. The availability of purified acinar cells in the investigation of interactions between hormones and cells from the mammary gland permits a greater degree of specificity than has been possible in the study of mammary cell suspensions which contain myoepithelial cells, duct cells, acinar cells, endothelial cells, fibroblasts, fat cells, mast cells, plasma cells, and blood cells.  相似文献   
72.
Collateral ligament attachments in distal femora and distal tibiotarsi were examined in broilers on ad libitum and restricted feeding and in laying strain fowls fed ad libitum. Histopathological studies revealed morphological changes in ligaments of ad libitum-fed broilers which were less apparent or absent in other birds examined. One such change was loss of crimp pattern in collagen bundles of ligaments, which suggested that structural derangement had occurred. Chondroid metaplasia and foci of hyaline cartilage were observed in ligaments of ad libitum-fed broilers and may result from tissue ischaemia. Similarities were noted between ligament attachments in broilers and Osgood-Schlatter disease in man; lesions in broilers may well have a similar aetiology. It is concluded that although feed restriction restores some semblance of normality in broiler ligaments, the propensity for abnormality remains and becomes apparent in heavier birds. Such reasoning casts doubt on the wisdom of modern broiler breeding practice where feed restriction can mask genotypic predisposition to clinical disease.  相似文献   
73.
OBJECTIVE: To determine whether fetal fibronectin (FFN) might serve as a marker to distinguish intrauterine versus extrauterine pregnancy. DESIGN: Prospective cohort study. SETTING: Academic research center. PATIENT(S): Cervicovaginal FFN samples were obtained from 46 women who were at high risk for or presented with signs and/or symptoms of extrauterine pregnancy. INTERVENTION(S): Samples of blood were analyzed for FFN with use of an enzyme-linked immunoabsorbent assay (ELISA). MAIN OUTCOME MEASURE(S): Fetal fibronectin level. RESULT(S): The rate of extrauterine pregnancy in our study was 26.1%, with 12 extrauterine and 34 intrauterine pregnancies identified by ultrasonography or at time of surgery. Seventeen samples had FFN levels of > 50 ng/mL and were considered positive (range, 0-1,000 ng/mL). Positive FFN levels were observed in 41.7% (5 of 12) of women with extrauterine pregnancies versus 35.3%) (12 of 34) of women with intrauterine pregnancies. The sensitivity, specificity, and positive and negative predictive values for extrauterine pregnancy were 41.7%, 64.7%, 29.4%, and 75.9%, respectively. CONCLUSION(S): The use of FFN does not appear to alter significantly the likelihood of identifying extrauterine pregnancy over current laboratory or ultrasonographic methods.  相似文献   
74.
The purpose of this study was to determine if a correlation exists between the intercondylar notch width (NW) of the femur and the width of the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). A study group of 124 consecutive patients (mean age 36.6 +/- 15.2 years; 67 men, 57 women) underwent a magnetic resonance imaging evaluation for knee pain but did not have an ACL or PCL tear or arthrosis. A T2 weighted coronal cut was identified and was located at the middle of the tibial spine, which represented the plane where the ACL and PCL cross each other when the knee is in 10 degrees of flexion. The NW and the width of the ACL and PCL were measured at the level of the middle of the popliteal hiatus on a physician-independent console that allowed for digital measurements in millimeters. Our results showed a statistically significant correlation between NW and ACL width (r = 0.87; P < 0.001) and between NW and PCL width (r = 0.75; P < 0.001). The mean ACL width was 6.4 +/- 1.4 mm (range 3-10 mm). The mean PCL width was 10.2 +/- 2.0 mm (range 6-17 mm). The mean ACL width was 5.7 +/- 1.1 mm for women and 7.1 +/- 1.2 mm for men (P < 0.001). The mean PCL width was 9.5 +/- 1.7 mm for women and 10.9 +/- 2.0 for men (P < 0.001). Our results indicate that NW correlates with ACL and PCL width. In addition, ACL and PCL widths are narrower in women than men.  相似文献   
75.
OBJECTIVE: The purpose of this study was to identify the success rates and risks in women with a twin pregnancy who attempt a trial of labor after cesarean delivery. STUDY DESIGN: Cases were identified in the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network's Cesarean Registry with a woman with a twin pregnancy who had had at least 1 previous cesarean delivery. RESULTS: During the study period (1999-2002), 412 women fulfilled the study criteria, and 226 women had elective repeat cesarean delivery. Of the 186 women (45.1% of total) who attempted a trial of labor, 120 women were delivered successfully (success rate, 64.5%), and 66 women (35.5%) had a failed trial of labor. Thirty of the failed trials of labor involved a vaginal delivery for twin A and cesarean delivery for twin B. Women who attempted a trial of labor with twins had no increased risk of transfusion, endometritis, intensive care unit admissions, or uterine rupture when compared with elective repeat cesarean delivery. Fetal and neonatal complications were uncommon in either group at>or=34 weeks of gestation. CONCLUSION: A trial of labor with twins after previous cesarean delivery does not appear to increase maternal morbidity. Perinatal morbidity is uncommon at>or=34 weeks of gestation.  相似文献   
76.
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78.
OBJECTIVE: Although repeat cesarean deliveries often are associated with serious morbidity, they account for only a portion of abdominal deliveries and are overlooked when evaluating morbidity. Our objective was to estimate the magnitude of increased maternal morbidity associated with increasing number of cesarean deliveries. METHODS: Prospective observational cohort of 30,132 women who had cesarean delivery without labor in 19 academic centers over 4 years (1999-2002). RESULTS: There were 6,201 first (primary), 15,808 second, 6,324 third, 1,452 fourth, 258 fifth, and 89 sixth or more cesarean deliveries. The risks of placenta accreta, cystotomy, bowel injury, ureteral injury, and ileus, the need for postoperative ventilation, intensive care unit admission, hysterectomy, and blood transfusion requiring 4 or more units, and the duration of operative time and hospital stay significantly increased with increasing number of cesarean deliveries. Placenta accreta was present in 15 (0.24%), 49 (0.31%), 36 (0.57%), 31 (2.13%), 6 (2.33%), and 6 (6.74%) women undergoing their first, second, third, fourth, fifth, and sixth or more cesarean deliveries, respectively. Hysterectomy was required in 40 (0.65%) first, 67 (0.42%) second, 57 (0.90%) third, 35 (2.41%) fourth, 9 (3.49%) fifth, and 8 (8.99%) sixth or more cesarean deliveries. In the 723 women with previa, the risk for placenta accreta was 3%, 11%, 40%, 61%, and 67% for first, second, third, fourth, and fifth or more repeat cesarean deliveries, respectively. CONCLUSION: Because serious maternal morbidity increases progressively with increasing number of cesarean deliveries, the number of intended pregnancies should be considered during counseling regarding elective repeat cesarean operation versus a trial of labor and when debating the merits of elective primary cesarean delivery. LEVEL OF EVIDENCE: II-2.  相似文献   
79.
OBJECTIVE: To determine whether the risk for uterine rupture is increased in women attempting vaginal birth after multiple cesarean deliveries. METHODS: We conducted a prospective multicenter observational study of women with prior cesarean delivery undergoing trial of labor and elective repeat operation. Maternal and perinatal outcomes were compared among women attempting vaginal birth after multiple cesarean deliveries and those with a single prior cesarean delivery. We also compared outcomes for women with multiple prior cesarean deliveries undergoing trial of labor with those electing repeat cesarean delivery. RESULTS: Uterine rupture occurred in 9 of 975 (0.9%) women with multiple prior cesarean compared with 115 of 16,915 (0.7%) women with a single prior operation (P = .37). Multivariable analysis confirmed that multiple prior cesarean delivery was not associated with an increased risk for uterine rupture. The rates of hysterectomy (0.6% versus 0.2%, P = .023) and transfusion (3.2% versus 1.6%, P < .001) were increased in women with multiple prior cesarean deliveries compared with women with a single prior cesarean delivery attempting trial of labor. Similarly, a composite of maternal morbidity was increased in women with multiple prior cesarean deliveries undergoing trial of labor compared with those having elective repeat cesarean delivery (odds ratio 1.41, 95% confidence interval 1.02-1.93). CONCLUSION: A history of multiple cesarean deliveries is not associated with an increased rate of uterine rupture in women attempting vaginal birth compared with those with a single prior operation. Maternal morbidity is increased with trial of labor after multiple cesarean deliveries, compared with elective repeat cesarean delivery, but the absolute risk for complications is small. Vaginal birth after multiple cesarean deliveries should remain an option for eligible women. LEVEL OF EVIDENCE: II-2.  相似文献   
80.
The cardio-active principle in spleen   总被引:1,自引:0,他引:1       下载免费PDF全文
A substance has been demonstrated in acetone extracts of freeze-dried spleen which had cardiotonic properties on isolated papillary muscles from the cat and perfused hearts of the cat and guinea-pig. This activity of the extract could not be explained by the presence of choline, acetylcholine, histamine, 5-hydroxytryptamine, adrenaline or noradrenaline.  相似文献   
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