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81.
82.
在一项随机、平行分组的开放试验中,27例妊娠糖尿病妇女(年龄30.7±6.3岁,HbA1c〈7%)随机分为门冬胰岛素治疗组(餐前5分钟注射)和常规人胰岛素治疗组(餐前30分钟注射)。试验时间为从诊断妊娠糖尿病(18~28周)至产后6周。研究期间两组的总体血糖水平均控制良好(试验开始和结束时HbA1c≤6%)。进餐试验时,试验6周时的平均血糖水平(门冬胰岛素组4.2±0.57mmol/L,常规人胰岛素组4.8±0.86mmol/L)略低于试验0周时(门冬胰岛素组4.9±0.59mmol/L,常规人胰岛素组5.1±0.36mmol/L)。  相似文献   
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Visual development was studied in 10 very-low-birth-weight infants (less than 1500 g) with retinopathy of prematurity (ROP) stage 3+ who had been treated with cryocoagulation in both eyes. Binocular visual acuity (acuity cards method) and binocular visual fields (kinetic perimetry) were assessed repeatedly in the first year of life. At 12 months corrected age, visual acuity was normal in seven and impaired in three infants, who appeared to be severely myopic. Normal visual fields were found in eight infants at this age. The results indicate that cryotherapy in cases of ROP stage 3+ does not interfere with visual acuity development. The effect on visual field development needs further investigation.  相似文献   
85.
OBJECTIVE: To document ocular penetration of oral tamoxifen in patients being administered systemic therapy by measuring intraocular and serum levels of the drug in a series of patients undergoing elective ocular surgery. DESIGN: Nonrandomized, prospective, comparative trial. PARTICIPANTS: Twenty-one eyes of 21 patients undergoing elective ocular surgery (cataract extraction or vitrectomy). Twenty patients were using the antiestrogen, tamoxifen, and one participant was not. Nine patients were excluded in the final analysis because of inadequate sample size. INTERVENTION: Preoperative serum samples and perioperative aqueous samples, vitreous samples, or both were obtained for each patient, and these were analyzed for tamoxifen and its metabolites. Dilated fundus examination was performed before surgery on all patients. MAIN OUTCOME MEASURES: Evidence of tamoxifen, its metabolites, or both in the samples. RESULTS: Tamoxifen was detected in all analyzed serum samples (range, 82.4-290.0 ng/ml.) from patients taking the medication and was found to have penetrated into both vitreous (range, 0.5-7.8 ng/ml) and aqueous (range, 0.5-3.9 ng/ml) cavities. No relationship was found between serum and intraocular levels. CONCLUSIONS: This study shows that tamoxifen penetrates intraocular fluids to varying degrees. The drug levels in aqueous and vitreous do not appear to correlate with serum levels. Evidence of tamoxifen retinopathy or keratopathy was not seen.  相似文献   
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Chemical studies of the CH2 Cl2 -MeOH extract of the seeds of Gambeya africana (Baker) Pierre led to the isolation of 15 compounds. Their structures were established on the basis of spectroscopic methods and chemical reactions. They comprised five new fatty acid esters of erythrodiol, [3 beta-octacosanoyloxy-12-oleanen-28-ol, 3 beta-triacontanoyloxy-12-oleanen-28-ol, 3 beta-dotriacontanoyloxy-12-oleanen-28-ol, 3 beta-tetratriacontanoyloxy-12-oleanen-28-ol and 3 beta-hexatriacontanoyloxy-12-oleanen-28-ol], one new steroidal glycoside, [3 beta-O-beta-xylopyranosylchondrillasterol] and nine known compounds, (3 beta-octadecanoyloxy-12-oleanene, 3 beta-eicosanoyloxy-12-oleanene, 3 beta-docosanoyloxy-12-oleanene, 3 beta-acetoxy-12-oleanene, erythrodiol, 28-hydroxy-beta-amyrone, chondrillasterol, chondrillasterone and 3 beta-O-beta-glucopyranosylchondrillasterol).  相似文献   
88.
89.

Background

Recent cadaver studies show stability against axial rotation with a cylindrical cage is marginally superior to a rectangular cage. The purpose of this biomechanical study in cadaver spine was to evaluate the stability of a new rectangular titanium cage design, which has teeth similar to the threads of cylindrical cages to engage the endplates.

Methods

Ten motion segments (five L2-3, five L4-5) were tested. From each cadaver spine, one motion segment was fixed with a pair of cylindrical cages (BAK, Sulzer Medica) and the other with paired rectangular cages (Rotafix, Corin Spinal). Each specimen was tested in an unconstrained state, after cage introduction and after additional posterior translaminar screw fixation. The range of motion (ROM) in flexion-extension, lateral bending, and rotation was tested in a materials testing machine, with +/- 5 Nm cyclical load over 10 sec per cycle; data from the third cycle was captured for analysis.

Results

ROM in all directions was significantly reduced (p < 0.05) with both types of cages. There was no significant difference in reduction of ROM in flexion-extension (p = 0.6) and rotation (p = 0.92) between the two cage groups, but stability in lateral bending was marginally superior with the rectangular cages (p = 0.11). Additional posterior fixation further reduced the ROM significantly (p < 0.05) in most directions in both cage groups, but did not show any difference between the cage groups.

Conclusions

There was no significant difference in immediate stability in any direction between the threaded cylindrical cage and the new design of the rectangular cage with endplate teeth.  相似文献   
90.
The rates of bronchiectasis for Indigenous children from remote Australian communities are unacceptably high, with one study showing 14.7/1000 Aboriginal children. Children with bronchiectasis need to be identified early for optimisation of medical treatment. Under-reporting of cough is common. Bronchiectasis should be suspected in children with recurrent bronchitis or pneumonia, and when, despite appropriate therapy, pulmonary infiltrates or atelectasis persist 12 weeks beyond the index illness. During acute infective episodes, oral antibiotics and chest physiotherapy to clear the airways should produce prompt resolution; otherwise, hospitalisation is necessary. Management follows the cystic fibrosis model of regular review, encouragement of physical activity, optimising nutrition, maintenance of immunisation and avoidance of environmental toxicants, including passive smoke exposure. Successful management and prevention of bronchiectasis will require improvements in housing, nutrition, and education, as well as access to comprehensive healthcare services, with coordination between primary and hospital-based healthcare providers.  相似文献   
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