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91.
Rate of rise in maternal plasma corticotrophin-releasing hormone and its relation to gestational length 总被引:1,自引:0,他引:1
Leung TN Chung TK Madsen G Lam PK Sahota D Smith R 《BJOG : an international journal of obstetrics and gynaecology》2001,108(5):527-532
Objective To assess the relationship between rate of increase in maternal plasma corticotrophin-releasing hormone and gestational length.
Design A prospective observational study.
Setting Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong Kong.
Methods Serial venous samples taken at four to six week intervals from 81 pregnant Chinese subjects were assayed for corticotrophin-releasing hormone concentrations. The investigators responsible for the laboratory assay were blinded to the obstetric outcome.
Results A total of 380 blood samples were taken. Each subject provided three to seven samples ( median =5 ). Seven of the 81 subjects had preterm delivery. Maternal corticotrophin-releasing hormone levels increased exponentially as gestation advanced. A negative correlation between the rate of rise of logarithmic equivalence of corticotrophin-releasing hormone concentrations (Ln-corticotrophin releasing hormone) per week and the gestational age at delivery was demonstrated ( r =−0.45, P <0.001 ). The rate of increase of Ln-corticotrophin releasing hormone concentrations per week was also significantly greater for those who delivered preterm before 37 weeks compared with those with uncomplicated term deliveries ( 0.27 Vs 0.22, P = 0.018 ).
Conclusions The rate of increase in maternal plasma corticotrophin-releasing hormone is inversely proportional to gestational length. Results in a Chinese population confirm and extend results from previous caucasian populations. This study provides another piece of evidence on the close link between maternal plasma corticotrophin-releasing hormone and the timing of human parturition. As the hormone is synthesized by the placenta, it supports the suggestion that the human placenta has an important role in determining gestational length. 相似文献
Design A prospective observational study.
Setting Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong Kong.
Methods Serial venous samples taken at four to six week intervals from 81 pregnant Chinese subjects were assayed for corticotrophin-releasing hormone concentrations. The investigators responsible for the laboratory assay were blinded to the obstetric outcome.
Results A total of 380 blood samples were taken. Each subject provided three to seven samples ( median =5 ). Seven of the 81 subjects had preterm delivery. Maternal corticotrophin-releasing hormone levels increased exponentially as gestation advanced. A negative correlation between the rate of rise of logarithmic equivalence of corticotrophin-releasing hormone concentrations (Ln-corticotrophin releasing hormone) per week and the gestational age at delivery was demonstrated ( r =−0.45, P <0.001 ). The rate of increase of Ln-corticotrophin releasing hormone concentrations per week was also significantly greater for those who delivered preterm before 37 weeks compared with those with uncomplicated term deliveries ( 0.27 Vs 0.22, P = 0.018 ).
Conclusions The rate of increase in maternal plasma corticotrophin-releasing hormone is inversely proportional to gestational length. Results in a Chinese population confirm and extend results from previous caucasian populations. This study provides another piece of evidence on the close link between maternal plasma corticotrophin-releasing hormone and the timing of human parturition. As the hormone is synthesized by the placenta, it supports the suggestion that the human placenta has an important role in determining gestational length. 相似文献
92.
93.
Angle closure glaucoma remains a major challenge for ophthalmologists. The three main challenges in the treatment of angle closure glaucoma are, firstly, to achieve rapid reduction of intraocular pressure in acute angle closure glaucoma, secondly, to prevent progression to chronic angle closure glaucoma, and thirdly, to manage established chronic angle closure glaucoma. Incisional surgery for angle closure glaucoma is typically required when laser surgery and/or medical therapy fail to control the intraocular pressure or control progressive synechial closure. The role for surgical iridectomy and emergency trabeculectomy in the modern management of acute angle closure glaucoma is diminishing. Trabeculectomy, goniosynechialysis, cyclodestructive procedures, and glaucoma implant are effective surgical options for chronic angle closure glaucoma, but none of them have been shown to be more effective than the others with proper comparative clinical trials. Trabeculectomy and goniosynechialysis are often combined with cataract extraction, which appears to offer additional pressure-control benefits to patients with chronic angle closure glaucoma. 相似文献
94.
95.
The combination of continuous intravenous infusion of diazepam (20--40 mg/kg per day) and intragastric phenobarbitone (10--15 mg/kg per day in 4 divided doses) was used to treat 19 cases of neonatal tetanus. Mortality was 2/19 (11%). This regimen was considered to have reduced the mortality and the need for artificial ventilation. The main side effects encountered were severe drowsiness, coma, and apnoeic episodes which were reversible when the level of diazepam was reduced. 相似文献
96.
In a randomized clinical trial designed to evaluate the effect of diuresis on infants with hyaline membrane disease, seven infants were treated with furosemide (2 mg/kg intravenously) and five received 5% dextrose water in 0.225% sodium chloride (control group). Arterial blood gas analyses performed before and during the six hours after treatment showed no significant difference between control and treated infants. Urine output and urine sodium and calcium loss were significantly increased (P less than .05) in the infants receiving furosemide. The diuresis seemed to have no effect on left atrial size determined echocardiographically, whereas measurements of dynamic skinfold thickness suggested mobilization of subcutaneous water. One infant became seriously dehydrated and hypotensive secondary to a massive diuresis. We concluded that furosemide had a potent diuretic effect in infants with hyaline membrane disease but does not improve cardiorespiratory function acutely. This may be because of failure to mobilize pulmonary interstitial fluid in the time period tested. It may also be possible that the presence of pulmonary interstitial fluid does not play an important role in the impairment of gas exchange in the acute stage of hyaline membrane disease. 相似文献
97.
PURPOSE: To study the safety and efficacy of intracameral lidocaine as anaesthesia in trabeculectomy for primary open-angle glaucoma. METHODS: Trabeculectomy under intracameral anaesthesia using 1% preservative-free lidocaine was performed in 10 patients with primary open-angle glaucoma. Intraoperative pain score, postoperative intraocular pressure (IOP) and endothelial cell count at 3 months were recorded. RESULTS: The mean pain score was 1.70 +/- 1.34. The mean IOP was lowered from 24.60 +/- 8.28 mmHg preoperatively to 14.1 +/- 3.11 mm Hg postoperatively. There was no significant decrease in the mean endothelial cell count 3 months after the surgery (P = 0.375). CONCLUSION: Intracameral lidocaine may be a safe and effective alternative anaesthesia method in trabeculectomy for uncomplicated primary open-angle glaucoma. 相似文献
98.
The use of postoperative topical mitomycin C in the treatment of recurrent conjunctival papilloma 总被引:2,自引:0,他引:2
PURPOSE: To describe the use of postoperative topical mitomycin C (MMC) in the treatment of recurrent conjunctival papilloma. METHODS: Case report. RESULTS: We report a 26-year-old man with recurrent conjunctival papilloma despite repeated surgical excision, cauterization, and cryotherapy. He was then treated with excision by cryotherapy, followed by a 2-week course of topical MMC eyedrops prescribed at postoperative day 7 (0.02 mg/mL, four times daily). No recurrence was observed 24 months postoperatively, and no complication was observed during the follow-up period. CONCLUSION: Postoperative topical MMC may be a useful adjunct in the management of recurrent conjunctival papilloma. 相似文献
99.
100.
BACKGROUND/AIMS: Racial variation in the pattern of strabismus is known, but few large scale studies on non-white populations are available. Furthermore, longitudinal change in this pattern within a local setting has not been well documented in the past. This study aims to support the clinical impression that exotropia is more common in Chinese patients, and that the proportion of patients with exotropia has been increasing in the past decade. METHODS: A total of 2704 consecutive patients with the diagnosis of primary horizontal strabismus, seen in the strabismus clinic of the Hong Kong Eye Hospital, were retrospectively analysed to determine the relative prevalence of esotropia and exotropia. Characteristics recorded include patient demographics, type of strabismus, and whether the nature of the squint was constant or intermittent. RESULTS: 742 (27.4%) patients were found to have esotropia, 548 (20.3%) had constant exotropia, 1213 (44.9%) had intermittent exotropia, and 201 (7.4%) had microtropia. The proportion of exotropic to esotropic patients was shown to increase steadily throughout the past decade (p<0.0001). This was mainly accounted for by an increase in the number of patients with intermittent exotropia, and a corresponding decrease in the number of patients with esotropia. CONCLUSION: Exotropia was shown to be more prevalent than esotropia in a Hong Kong Chinese population. Furthermore, the proportion of patients with intermittent exotropia appears to be increasing, in contrast with esotropic patients. The exact nature of this trend, and possible aetiological factors will require further study. 相似文献