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OBJECTIVE: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. METHODS: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. RESULTS: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. CONCLUSION: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.  相似文献   
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The aim of this study was to evaluate the effects of tamoxifen on tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) levels and ultrastructural changes in rats with spinal cord injury. Rats were divided into four groups: control group (laminectomy only), trauma group (laminectomy + spinal trauma), tamoxifen group (laminectomy + spinal trauma + tamoxifen), and vehicle group (laminectomy + spinal trauma + vehicle). Spinal cords were extirpated at the T7–T12 level and tissue samples from the spinal cords were gathered for TNF-α and IL-1β measurements at 1 and 6 hours. Spinal cords harvested at 6 hours were evaluated for ultrastructural changes. TNF-α and IL-1β levels at 6 hours were significantly lower in the tamoxifen group than in the trauma group. Electron microscopic examination of tissue from the trauma group revealed gross cell deformities with widespread edema of all structures as well as severe edema in the neuropil. At 6 hours after trauma, these ultrastructural changes were less marked in the tamoxifen group. Our findings support a neuroprotective and restorative role for tamoxifen in the context of secondary pathological biochemical events after SCI.  相似文献   
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BackgroundOsteoblasts and osteoclasts are known to express Ang II type I (AT1) receptor in cell cultures, suggesting the existence of local renin-angiotensin system (RAS) in bone. This study was designed to investigate the effects of losartan as AT1 receptor blocker on ovariectomized rats' femur.MethodsLosartan (5 mg/kg/day) was administered via oral gavage for 8 weeks. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, while tensile and three-point bending tests were performed for evaluation of biomechanical properties of bone. The trabecular porosity was analyzed by scanning electron microscopy.ResultsThere was a significant decrease in BMD values of ovariectomized rats' femurs which were reversed by losartan treatment. According to tensile test results, ultimate tensile strength and strain values of losartan treated ovariectomized rats' femurs increased and decreased, respectively, when compared to that of ovariectomized animals. Losartan treatment also caused a significant recovery in flexural strength and modulus parameters regarding respective control values, which mean losartan treated ovariectomized rats' femur had more force tolerance until break than ovariectomized rats' femur. Quantitative microscopic analysis showed larger trabecular porosity in ovariectomized rats than control rat femurs and it was significantly decreased after losartan treatment.ConclusionBlockage of AT1 receptor increased strength, mass and trabecular connections of ovariectomized rat femurs. Therefore, it is tempting to speculate that drugs, including AT1 receptor blockers, may be used for the treatment of osteoporosis or reduction of its detrimental effects in the future.  相似文献   
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OBJECTIVES: To investigate the effects of valproic acid on vestibular symptoms and electronystagmography (ENG) findings in patients with migraine-related vestibulopathy. METHODS: Thirty-seven patients with migraine (13 with vertigo, 13 with dizziness, and 11 without vestibular symptoms) were included in the study. Slow-released valproic acid (500 mg/d) was given for 3 months. Frequency of headache and vestibular symptoms in the first, second, and third months of the therapy were recorded and compared with the pretreatment values. The ENG findings were also evaluated before and 2 months after the therapy. RESULTS: We determined that prophylactic low-dose valproic acid decreased the frequency of headache and vestibular symptoms, although it does not cause any statistically meaningful change in ENG findings. CONCLUSIONS: Valproate can be used satisfactorily for patients with migraine who have vestibular complaints. Ineffectiveness of valproic acid on ENG findings can be clarified by the permanent effect of migraine on the vestibular system.  相似文献   
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Bile ducts of Luschka (also called subvesical or supravesicular ducts) can cause bile leakage during laparoscopic cholecystectomy, especially if surgery is carried out in ignorance of such variations. The aim of this study was to clarify the clinical anatomy of these ducts in human fetuses and frequency of the ducts locating near gallbladder fossa. Thirty-two fetal cadaver livers were dissected and the gallbladders were separated from the livers and ducts were investigated under a surgical microscope. All observed ducts were examined microscopically and connective tissue cords were excluded. Bile ducts of Luschka locating near cystic fossa were found in 7 of 32 fetuses (21.9%). Three of the seven ducts ran towards to liver segment 5 (S5); three ducts were found in the gallbladder fossa; and one duct ran towards to liver segment 4 (S4). Also it was found that three of the seven ducts drained into the subsegmental duct of S5, two ducts drained into the right hepatic duct, one duct drained into the right anterior branch bile duct, and one duct drained into the subsegmental duct of S4. Subvesical ducts running along the gallbladder fossa between the gallbladder and the liver parenchyma were found in a relatively high incidence in fetuses than adults. Awareness and knowledge about incidence of such ducts alerts the surgeon during laparoscopic cholecystectomy. Therefore morbidity due to bile leaks can be reduced.  相似文献   
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OBJECTIVE: Neonatal care provided within the first few minutes of life plays a major role in the reduction of neonatal morbidity and mortality. Neonatal Resuscitation Program (NRP) courses had been held since 1996. The aim of this study was to evaluate the impact of the NRP on morbidity and mortality of newborn infants with perinatal asphyxia. METHODS: This retrospective study comprised newborn infants who were born in hospitals at Trakya region of Turkey during the last 3 years and were diagnosed as perinatal asphyxia and were referred to our Neonatal Unit. Those patients who were referred before NRP course (pretraining period) were designated as Group 1, those who were referred after the first NRP course (transition period) as Group 2, and those who were referred after the second NRP course (post-training period) as Group 3. Chart review was performed with regard to gestational age, birth weight, Apgar scores, resuscitation type, stage of hypoxic ischemic encephalopathy (HIE), existence of meconium aspiration syndrome (MAS), progress of the disease, duration of hospitalization. RESULTS: The study comprised 66 patients; 35 in Group 1, 18 in Group 2 and 13 in Group 3. The number of cases who had not been resuscitated was 10 in the pretraining period, 3 in the transition period and 1 in the post-training period which decreased significantly. The first minute Apgar scores in three groups were as follows; 2.08+/-1.2, 2.2+/-1.1 and 3.7+/-1.4, and this increase was statistically significant. The fifth minute Apgar scores also increased from 5.43+/-1.5 in the pretraining period to 6.5+/-1.9 in the post-training period, but this increase was not statistically significant. The number of patients with Stage 1 and 2 HIE decreased more in Group 3 (n=11 in Stage 1 HIE, n=17 in Stage 2 HIE) compared to those in Group 1 (n=7 in Stage 1 HIE, n=5 in Stage 2 HIE) but the difference was not statistically significant. The duration of hospitalization decreased in post-training period (15.1+/-10.3 days in pretraining period, 12.0+/-8.9 days in transition period, 6.1+/-1.2 days in post-training period). CONCLUSIONS: After NRP courses, the number of patients with perinatal asphyxia and with no resuscitation and also the duration of hospitalization decreased significantly, whereas the first minute Apgar scores increased significantly.  相似文献   
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OBJECTIVES: Esophageal strictures and esophagorespiratory fistulas are complications of malignant esophageal tumors, which are difficult to manage. The efficacy of self-expanding metal stents (SEMS) for palliation of malignant esophageal strictures and fistulas was investigated prospectively. METHODS: Forty-three SEMS were inserted in 41 patients with malignant esophageal stricture or fistula. Our series included 32 men and nine women, of whom median age was 61.4 years. Twenty nine stents were inserted for stricture, ten for esophago-tracheal fistula, and four esophago-pleural fistula. Stents were inserted endoscopically under fluoroscopic control. RESULTS: SEMS implantation was technically successful in 40 of 41 patients. A second stenting was needed in two patients. Median dysphagia score improved from 3.4 to 1.3. The covered SEMS was succesful in completely sealing 85.7% of the fistulas. Complication occurred in 11 (26.8%) patients. Especially in the case of tumor stenoses in the distal esophagus, complication rate was higher (44%). In total six patients (14.6%) died after stent placement during early postoperative period. Procedure-related mortality was 4.8% (2/41). CONCLUSIONS: We conclude that treatment of malignant esophageal obstructions, including esophagorespiratory fistulas, with SEMS is an alternative palliative procedure. Furthermore SEMS implantation seems more safe in the case of tumor stenoses locating in the middle esophagus.  相似文献   
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