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51.
BACKGROUND: Although seasonal variation of birth weight has been reported previously, contributing factors such as the meteorological factor and its specific period of exposure remain unclear. AIM: To investigate the effect of season on birth weight and to determine the meteorological factor and its specific period of exposure which can contribute to any seasonal variation in birth weight. METHODS: Retrospective analysis of 3333 singleton live births after 36 completed weeks of pregnancy. Maternal age, parity, route of delivery, sex and individual meteorological variables for the first, second, and third trimesters of each pregnancy were analysed using multiple regression analysis with the birth weight as the dependent variable. RESULTS: A seasonal pattern was observed with lowest birth weights in women who had their last menstrual periods in summer and autumn. Upon multiple regression analysis, sex, parity, mode of delivery, and the temperature which the mother was exposed to in the second trimester were the independent determinants of birth weight. CONCLUSION: Exposure to low outdoor ambient temperature in the midtrimester can be associated with low birth weight.  相似文献   
52.
OBJECTIVE: The aim of this study was to determine the syndromic etiology of bilateral severe sensorineural hearing disorders in children and current etiological causes to reduce the cases in the unknown group. METHODS: This study was conducted on 550 students of five schools for the deaf in Istanbul and Zonguldak, Turkey. Otologic, audiologic, dysmorphologic, ophthalmologic and dental examinations were performed in all children. Familial and medical histories were obtained. RESULTS: The etiology of hearing loss was genetic in 346 (62.90%), acquired in 107 (19.45%) and unknown in 97 (%17.63) cases. A total of 619 malformations were defined in 550 children and 99 of them belonged to a syndrome. We identified 33 different syndromes for these 99 syndromic children. Syndromic etiology was found in 18.0% of the total and 28.61% of the subjects with genetic etiology. Most common syndrome was Waardenburg syndrome which occurred in 33 children. CONCLUSION: The incidence of hereditary hearing impairment is very high in developing countries compared to developed countries. Prevention is essential to reduce the incidence, multidisciplinary approach and genetic counselling are necessary in this regard.  相似文献   
53.
PURPOSE: To determine the short-term effects of latanoprost on retrobulbar circulation in ocular hypertension. METHODS: Forty-six eyes of 23 consecutive bilateral ocular hypertensive patients with an intraocular pressure (IOP) of greater than 22 mmHg were evaluated in a prospective controlled study. All subjects received a single drop of latanoprost 0.005% in one eye and placebo in the fellow control eye. Systemic circulatory parameters, intraocular pressure, blood flow velocities, and resistance indices of the ophthalmic, short posterior ciliary and central retinal arteries were measured using colour Doppler imaging at baseline and 2 h and 8 h after dosing. RESULTS: Latanoprost lowered IOP significantly after 2 h and 8 h (P < 0.01). The mean IOP reduction was 6.7 mmHg 8 h after dosing. At baseline, there were no statistically significant differences in any retrobulbar vessels of eyes that received a single drop of latanoprost when compared with the eyes that received placebo (P > 0.05). Comparisons with baseline and latanoprost conditions revealed that latanoprost did not alter the blood flow velocities and resistance indices in the ophthalmic (P > 0.05), posterior ciliary (P > 0.05) and central retinal (P > 0.05) arteries 2 h and 8 h after dosing. The systolic and diastolic blood pressures (p = 0.74, p = 0.29, respectively) and pulse rate (p = 0.68) remained unchanged over the 8-h period. CONCLUSIONS: This study found that a single drop of latanoprost significantly reduces intraocular pressure 8 h after dosing. However, it does not have any short-term effects on the retrobulbar haemodynamics in ocular hypertensive eyes.  相似文献   
54.
Reaction of 7-hydroxy-4-methyl coumarin with amido/ imido alcohols in ethanol containing concentrated hydrochloric acid afforded 8-aralkyl amido/imido-alkyl-7-hydroxy-4-methyl-coumarins (1a-f). Interaction of 1a-f with hydrazine hydrate in pyridine resulted in 1-amino-8-aralkyl amido/imido-alkyl-7-hydroxy-4-methyl-2-oxo-quinolines (2a-f). Treatment of 2 with formaldehyde in ethanol resulted in 1,3,5-tris-(8-aralkyl amido/imido-alkyl-7-hydroxy-4-methyl-2-oxo-quinolinyl)-2,4,6-hexahydro-s-triazines (3a-c). Antiviral activity of compounds 2a-d and 3a, 3b upon Japanese encephalitis virus (JEV) and Herpes simplex virus-1 (HSV-1) was evaluated on vero cells in vitro. 3a-c were also screened for their antihypertensive activity.  相似文献   
55.
Color Doppler imaging in ocular hypertension and open-angle glaucoma   总被引:7,自引:0,他引:7  
Purpose To quantify the retrobulbar hemodynamics of patients with ocular hypertension and open-angle glaucoma and to compare it with that of normal subjects.Methods Nineteen eyes of 19 ocular hypertensive patients, 19 eyes of 19 open-angle glaucoma patients and 19 eyes of 19 normal subjects were recruited from our clinic and underwent color Doppler imaging evaluation of the ophthalmic, posterior ciliary, and central retinal arteries. The peak systolic and end-diastolic blood flow velocities and resistivity indices of all retrobulbar vessels were measured.Results The retrobulbar blood flow velocities were lower and resistivity indices were higher in all retrobulbar vessels in ocular hypertensive patients than in normal subjects. The differences, however, did not reach statistical significance (P>0.05). Glaucoma patients had lower end-diastolic velocities and higher resistivity indices than did normal subjects in the ophthalmic (P=0.003 and P=0.003, respectively), posterior ciliary (P=0.001 and P<0.001, respectively), and central retinal arteries (P=0.03 and P=0.04, respectively). Glaucoma patients had significantly lower end-diastolic velocity and higher resistivity index than did patients with ocular hypertension in the posterior ciliary artery (P=0.04 and P=0.001, respectively).Conclusions This study suggests that ocular hypertensive patients have more normal blood flow than do glaucoma patients, because all retrobulbar homodynamic measurements in ocular hypertension range between glaucoma and normal subjects. On the other hand, glaucoma is associated with blood-flow velocity reduction and resistivity index elevation in all retrobulbar arteries.  相似文献   
56.
The aim of this study was to compare vertebral bone mass values of patients with central precocious puberty (CPP) with healthy age and puberty matched controls and to determine the effect of gonadotropin releasing hormone (GnRH) analogs on bone mass in patients who had been treated at least for 1 year. Girls with idiopathic CPP, 11 pretreatment, 14 post-treatment, and 19 pubertal girls as controls were enrolled in the study. The mean ages of the controls and the patients with CPP pre- and post-treatment were 10.25 +/- 1.06, 8.23 +/- 1.11, and 10.36 +/- 1.82 years, respectively. Leuprolide acetate (Lucrin) 3.75 mg was administered s.c. monthly. Bone measurements were performed by dual energy X-ray absorptiometry (DEXA) (Norland) at the anterior-posterior vertebrae (L2-L4). The post-treatment group's mean BMD value was 0.66 +/- 0.12; Z scores according to CA and BA were 0.32 +/- 10 and 0.30 +/- 1.1, respectively. In the study group, BMD values compared to the control group were normal. No significant change in BMD values was observed after treatment. Neither osteopenia nor osteoporosis was observed in patients taking GnRH analog.  相似文献   
57.
We describe a 45-yr-old woman with an intermediate type atrioventricular septal defect associated with a double-orifice left atrioventricular valve (DOLAV). We diagnosed this exceptional anomaly by intraoperative transesophageal echocardiography (TEE) during surgery that was scheduled for only a primum type atrial septal defect (ASD) repair. Preoperative transthoracic echocardiography and angiography revealed the ASD but could not demonstrate the DOLAV. We were able to repair this rare and challenging abnormality successfully under the guidance of TEE imaging during the operation. TEE provides valuable information about both anatomy and functional aspect of the valvular structures. Besides its proven role in cardiac surgery, intraoperative use of TEE also serves as a useful tool for diagnosis of such unexpected and potentially missed abnormalities.  相似文献   
58.
59.
Kara M  Bulut S  Tas F  Akkurt I  Seyfikli Z 《European radiology》2003,13(10):2372-2377
Biomass fuels are frequently used in rural areas of the world for cooking and heating frequently. It has been reported that the use of these fuels causes hazardous effects on the lungs. In this study, we evaluated the pulmonary changes due to the use of biomass fuels in a female population that lives in our territory by high-resolution computed tomography (HRCT). The study analyzed three groups of women. The first group comprised those subjects who were exposed to biomass without respiratory symptoms (group 1; n=32). The second group comprised those individuals that were exposed to biomass and showed respiratory symptoms, such as cough, sputum production, and dyspnea (group 2; n=30). The third group was composed of women who were not exposed to biomass and also had no respiratory symptoms (group 3; n=30). Women with a history of concomitant pulmonary diseases were excluded from the study. All groups were examined with HRCT. Groups 1 and 2 (individuals exposed to biomass fuels) had more pathologic findings than group 3 (not exposed to biomass fuels). Ground-glass appearance was seen in 71.9% in group 1, 23.3% in group 2, and 3.3% in group 3. The difference between the groups was statistically significant (p<0.05). Fibrotic bands were seen 50% in group 1, 63.3% in group 2, and only 6.7% in group 3 (p<0.001). Exposure to biomass fuels was the cause or predisposing factor for many pulmonary diseases, ranging from chronic bronchitis to diffuse lung diseases. We believe that these pathological changes due to biomass fuels can be detected earlier by HRCT and the diseases might be prevented or treated earlier.  相似文献   
60.
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