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OBJECTIVE: To identify independent predictors of successful labor induction with oral or vaginal misoprostol. METHODS: Women enrolled in four previous randomized trials involving oral or vaginal misoprostol for cervical ripening and labor induction were included in the present cohort study, with dosing of 25-50 microg every 4 to 6 h vaginally (n = 574) or 50 microg every 4 h orally (n = 207). Multiple logistic regression was performed to identify factors independently associated with successful labor induction -- defined as vaginal delivery within 12 h, vaginal delivery within 24 h and spontaneous vaginal delivery. Predictors of Cesarean birth and the need for only one dose of misoprostol were also identified. Variables included in the models were maternal age, weight, height, parity, gravidity, membrane status, route of misoprostol, gestational age, birth weight, and Bishop score and its individual components. RESULTS: Maternal age, height, weight, parity, birth weight, dilatation, effacement and cervical station were associated with vaginal delivery within 24 h of induction. Maternal age, height, weight, nulliparity, birth weight and route of misoprostol were associated with Cesarean birth, with oral misoprostol being associated with a lower rate of Cesarean birth. The need for only one dose of misoprostol was predicted by maternal height, weight, parity, gestational age, Bishop score and route of misoprostol. CONCLUSION: Characteristics of the woman (height, weight, parity), the fetus (birth weight) and some of the individual components of the Bishop score, were associated with successful labor induction, with oral misoprostol being associated with a lower rate of Cesarean birth.  相似文献   
73.
Schick  PK; Wojenski  CM; Bennett  VD; Ivanova  T 《Blood》1996,87(5):1817-1823
There are several species of alternatively spliced fibronectin (FN). One of these, FN EIIIB, is primarily present in embryonic and in proliferating and migrating cells and is believed to be important for cell maturation. We have studied the synthesis, localization, and secretion of this FN isoform in isolated guinea pig megakaryocytes, nonmegakaryocytic bone marrow cells, and platelets. There was 7.5 times more general FN in megakaryocytes than in nonmegakaryocytic cells based on the analysis of equivalent amounts of protein. FN EIIIB was detected by Western blotting in megakaryocytes but not in nonmegakaryocytic cells present in bone marrow. Neither megakaryocytes nor platelets secreted FN EIIIB, while megakaryocytes secreted 25.3% +/- 4.6% general FN and platelets secreted about 61% general FN in response to thrombin. Analysis of immunostained cells by confocal microscopy revealed that FN EIIIB had been redistributed to the surface of megakaryocytes in response to thrombin. Synthesis was studied by metabolic labeling, and megakaryocytes were shown to synthesize FN and FN EIIIB. Thus, megakaryocytes and platelets are among a small number of adult cells and tissues that synthesize and contain FN EIIIB. The expression of FN EIIIB on the megakaryocyte surface may influence migration and maturation.  相似文献   
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1. Conscious, chronically-instrumented, Long Evans rats were given bolus doses of endothelin-1, endothelin-3 (both at 0.01 and 0.1 nmol kg-1), proendothelin-1 [1-38] and proendothelin-3 [1-41] (both 0.1 and 1 nmol kg-1) in order to compare their effects on coeliac haemodynamics, because it has been reported that, in conscious dogs, endothelin-1 has paradoxical, prolonged hyperaemic vasodilator effects in this vascular bed. Measurements were made also of mesenteric and hindquarters haemodynamics for comparison. In a separate experiment, endothelin-1 (0.1 nmol kg-1) was given before and 20 min after the onset of an infusion of mecamylamine (50 mumol kg h-1) to ensure that the responses measured were not confounded by rapid reflex changes in autonomic activity. 2. None of the peptides caused any increases in coeliac flow or any sustained rises in coeliac vascular conductance, although such changes were clear-cut in the hindquarters vascular bed following the higher dose of endothelin-1 and endothelin-3. In animals treated with mecamylamine the regional haemodynamic effects of the higher dose endothelin-1 were not different from those in animals with intact baroreflexes. 3. Although the lower dose of both endothelin-1 and endothelin-3 caused less marked coeliac, than mesenteric vasoconstriction, this difference was not apparent with the higher dose of the peptides, or with proendothelin-1 [1-38]. However, proendothelin-3 [1-41] had less marked coeliac and hindquarters vasoconstrictor effects than proendothelin-1 [1-38], in spite of both peptides causing similar changes in mesenteric haemodynamics.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
Preinvasive lesions of squamous cell carcinoma are well defined morphologically and provide a model for multistage carcinogenesis. Since alterations in the p53 tumor suppressor gene occur frequently in invasive esophageal squamous cell carcinoma, we examined a set of preinvasive lesions to investigate the timing of p53 mutation. Surgically resected tissues from nine patients with esophageal squamous cell carcinoma contained precursor lesions which had not yet invaded normal tissues. Immunohistochemistry showed high levels of p53 protein in both preinvasive lesions and invasive carcinomas in six cases; sequence analysis of all invasive tumors identified p53 missense mutations in two cases. Preinvasive lesions from both tumors with mutations plus one wild-type tumor were microdissected and sequenced. In one patient there were different mutations in the invasive carcinoma (codon 282, CGGarg > TGGtrp) and a preinvasive lesion (codon 272, GTGval > T/GTGleu/val). In a second case, an invasive carcinoma had a mutation in codon 175 (CGCarg > CAChis), and adjacent preinvasive lesions contained a wild-type sequence. A carcinoma and preinvasive lesion from the third case contained high levels of protein and a wild-type DNA sequence. Therefore, p53 mutation may precede invasion in esophageal carcinogenesis, and multifocal esophageal neoplasms may arise from independent clones of transformed cells. The timing of p53 protein accumulation is favorable for an intermediate biomarker in multistage esophageal carcinogenesis.  相似文献   
78.
Early identification of disabilities enables early intervention by occupational therapists and other health professionals. Because the number of children who can be seen in therapy is limited, it is important to be able to identify those infants most likely to have deficits at a later age. Therefore, it is necessary to study and understand the relationship between infants' scores on early developmental assessments and later developmental outcomes. The purpose of this study was to determine the extent to which scores on the Bayley Scales of Infant Development (BSID) during the first 2 years of life are related to motor and cognitive performance at 4 1/2 years for a sample of children identified at birth as biologically high risk. This retrospective study involved 70 children who were evaluated at corrected ages of 4 months, 1 year, 2 years, and 4 1/2 years. The 4-month BSID Mental and Motor Scale scores did not relate significantly to later cognitive motor performance. In contrast, the 12-month BSID Mental Scale scores related significantly to preschool scores on both the motor and cognitive measures. However, the 24-month BSID Mental Scale scores related significantly only to scores on the preschool cognitive measures. Though significant, these correlation coefficients had small magnitudes. Thus, therapists should be cautious about using BSID testing at 4 months, 1 year, and 2 years when attempting to predict later preschool performance.  相似文献   
79.
1. Conscious, Long Evans rats (n = 10), chronically instrumented for the measurement of regional haemodynamics, were studied on 3 consecutive experimental days to assess responses to angiotensin II (AII) (125 pmol kg-1, i.v.) and noradrenaline (1 nmol kg-1, i.v.) in the absence and presence of the AT2-receptor antagonist, PD 123319 (10 mg kg-1, i.v.) (day 1), the AT1-receptor antagonist, EXP 3174 (1 mg kg-1, i.v.) (day 2), and PD 123319 (10 mg kg-1, i.v.) given 24 h after EXP 3174 (day 3). 2. In naive rats (day 1), PD 123319 did not antagonize the haemodynamic effects of AII or noradrenaline. EXP 3174 (day 2) caused a marked, prolonged blockade of the haemodynamic effects of AII but not those of noradrenaline. Twenty four h after administration of EXP 3174 (day 3) there was still significant attenuation of the haemodynamic effects of AII. However, administration of PD 123319 at this time caused a further inhibition (lasting 1 h) of the effects of AII but not those of noradrenaline. 3. An identical 3 day protocol was used in a separate group of rats (n = 6) in which the AT2-receptor antagonist, PD 123177, was given instead of PD 123319, and the results were essentially the same, i.e., PD 123177 significantly attenuated the haemodynamic effects of AII but only when given 24 h after EXP 3174.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
80.
Two discrete areas of the chick brain, the intermediate medial hyperstriatum ventrale (IMHV) and lobus parolfactorius (LPO), were found to have different functions during the formation of memory for a 1-trial peck-avoidance paradigm. Glutamate, ouabain, and emetine, known to disrupt short-, intermediate-, and long-term memory when injected into the IMHV, were injected into the cerebellum and LPO. All amnestic agents investigated produced amnesia when injected into the IMHV; only one of these agents produced amnesia when injected into the LPO, and none of the agents produced amnesia when injected into the cerebellum. The chick brain was also found to exhibit hemispheric asymmetries: The left IMHV and LPO were more sensitive to the amnestic agents than their corresponding right structure. From these data, hypotheses for the roles of these structures during memory are proposed.  相似文献   
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