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Objective. To determine the rate, delivery outcome and safety of attempted vaginal birth after cesarean section (VBAC) in grand multiparous women (para 6 or more). Methods. This is a retrospective case-control study, performed at King Abdulaziz university hospital, the charts of 405 grand multiparous women with previous caesarean section were reviewed to determine rate and delivery outcome of attempted VBAC. The outcome of 217 VBAC in grand multiparous women was compared to the outcome of 217 VBAC in multiparous women (para 2–5) during the same period. Results. The rate of VBAC in grand multiparous women was 53.6%. One hundred-seventy five (80.7%) grand multiparous women were delivered vaginally compared to 170 (78.3%) in multiparous women, this was not statistically significant difference. Sixteen (7.4%) grand multiparous women need labor augmentation with oxytocin, while 34 (16%) in multiparous women, this was statistically significant difference (P value 0.005). The labor duration was 6.4±3.5 h in grand multiparous women compared to 9.0±4.3 h in multiparous women, and was also statistically significant difference (P value 0.001). The fetal weight, Apgar scores, postpartum hemorrhage, fever and number of hospital days in the two groups, were not statistically significant differences. In the control multiparous women there was one uterine rupture, two uterine dehiscence, and one stillbirth due to placental abruption. Conclusion. VBAC in grand multiparous women is common practice, safe and efficacious. High parity in association with vaginal deliveries is good prognostic factor and also can predict successful VBAC outcome. However, further studies are needed to confirm our findings.  相似文献   
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OBJECTIVE: The purpose of this study was to compare the descent curves and second-stage length among grand multiparous, nulliparous, and lower parity multiparous women. STUDY DESIGN: Retrospective cohorts of spontaneously laboring, vertex-presenting, term, grand multiparous women (parity >or=5) from two medical centers over 5.5 years were matched randomly to nulliparous women and lower parity multiparous women controlled for age, hospital, and year of delivery. Descent curves were modeled from serial cervical examination data by the estimation of the probability of a given station occurring at a given time before delivery with the use of ordinal logistic regression. Curves were compared by Wald tests and adjusted for possible confounders. Second-stage lengths were compared by a Cox proportional hazards model. A probability value of <.05 was considered significant. RESULTS: Grand multiparous women and lower parity multiparous women maintain a high station up to 1.5 hour before delivery and then rapidly transition to delivery. Nulliparous women transition to lower stations at a more gradual rate throughout the first and second stages. Descent curves differ among parity groups, with grand multiparous women maintaining a higher station for a longer time compared with either lower parity multiparous women or nulliparous women (P<.001). Once full dilation is reached, the median length of the second stage is 0.75, 0.85, and 1.75 hours for grand multiparous women, lower parity multiparous women, and nulliparous women, respectively (hazard ratios were 0.39 for nulliparous women vs grand multiparous women and 0.9 for lower parity multiparous women vs grand multiparous women). CONCLUSIONS: Compared with lower parity multiparous women or nulliparous women, grand multiparous women maintain a higher station for a longer time before delivery but transition rapidly to delivery once full dilation is reached.  相似文献   
415.
The effect of various nucleotide-enhancing agents on renal function and intracellular nucleotide levels was evaluated in a canine autotransplant model. Thirty-five dogs (18-28 kg) underwent left nephrectomy and 30 min of warm ischemia followed by Collins C-4 flush and 24 hr of cold-storage preservation. Heterotopic autotransplantation and immediate contralateral nephrectomy was then performed. Seven equal groups were evaluated: group A--controls, group B--adenosine pretreatment (1.0 g), group C--dipyridamole pretreatment (10 mg), group D--adenosine (1.0 g), and dipyridamole (10 mg) pretreatment, group E--adenosine (200 mg) and EHNA (2.5 mg/kg) pretreatment, group F--adenosine (200 mg) and EHNA (2.5 mg/kg) in the Collins C-4 flush, and group G--adenosine (200 mg) and EHNA (2.5 mg/kg) at the time of autotransplantation. All kidneys underwent cortical biopsies at the end of preservation and 1 hr after restoration of blood flow for determinations of AMP, ADP, and ATP. In the pretreatment groups (groups B through E) there was 60% graft survival whereas the controls (group A) and the groups treated after ischemia (groups F and G) had 0, 0, and 20% graft survival, respectively. In groups B and E, ATP levels were greater than controls after preservation and 1 hr after restoration of blood flow. Group C AMP and ADP levels and group D energy charge were greater than controls in the post-transplantation biopsies. Administration of adenosine and EHNA after ischemia was not associated with increased intracellular nucleotide levels. One hour post-transplantation biopsies demonstrated greater ability to regenerate cortical nucleotides in the surviving animals but no absolute value could be identified as a predictor of viability. In conclusion, pretreatment with adenosine, dipyridamole, and EHNA alone and in combination is beneficial in ischemically injured kidneys undergoing cold-storage preservation.  相似文献   
416.
Recurrence of arteriovenous malformation is inevitable unless the total malformation is resected. Bony involvement in some of these malformations contributes to a quick recurrence when limited resection is undertaken. Although arteriography is the procedure of choice in delineating vascular and soft tissue involvement with the malformation, it does not outline osseous involvement. Xeroradiography is an adjunctive diagnostic procedure that provides information about bony involvement, which will assist in planning the total resection of the malformation. In two cases, xeroradiography was helpful in defining the limits of surgical excision.  相似文献   
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Intracardiac sound was measured in six dogs, four with left ventricular cavity obliteration induced by isoproterenol, and two with catheter entrapment. In left ventricular cavity obliteration, no murmur occurred within the left ventricle. Whenever a systolic murmur occurred, it was distal to the aortic valve. In entrapment, no murmur occurred within the left ventricle or distal to the aortic valve. Previous studies in patients with hypertrophic obstructive cardiomyopathy showed that the systolic murmur was of greatest intensity within the left ventricular outflow tract. Therefore, intracardiac phonocardiography may assist in differentiating these conditions which produce an intraventricular pressure gradient.  相似文献   
419.
To evaluate the essentiality of creatine and phosphocreatine for the maintenance of the ultrastructure of skeletal muscle, chicks were fed a creatine antagonist, β-guanidinobutyric acid (β-GBA), as 2% of a Chow diet. Chicks fed β-GBA exhibited growth retardation and weakness, and they accumulated large amounts of a monosubstituted guanidino compound, presumably β-GBA, in their skeletal muscles. After 2 wk, there was a 74% decrease in the uptake of [14C]-1-creatine into pectoralis muscles of chicks fed β-GBA. After 3 wk there was a significant decrease in phosphocreatine concentrations in pectoralis muscles from 20.1 ± 2.8 μmoles per g wet weight (mean ± S.D.) for 8 control chicks to 16.5 ± 2.5 for 7 chicks fed β-GBA. Selected fibers of the pectoralis and gastrocnemius muscles of chicks fed β-GBA exhibited ultrastructural abnormalities including loss of thick and thin filaments, disruption of the Z band, dilated mitochondria, and dilated and displaced sarcoplasmic reticulum. The pectoralis muscles of chicks given 6% creatine in addition to 2% β-GBA in the diet accumulated little β-GBA, maintained normal phosphocreatine concentrations, and exhibited no significant ultrastructural abnormalities. These findings are the first experimental evidence that high concentrations of phosphocreatine are essential for the maintenance of the ultrastructural integrity of skeletal muscle.  相似文献   
420.
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