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61.
This study was designed to analyze the effect of early indomethacin on the lipid peroxidation after spinal cord injury in rats. The use of anti-inflammatory drugs to affect delayed and secondary injury after trauma to the spinal cord has now become a matter of standard clinical practice. However, spinal cord injury remains an enormous clinical problem and research that may lead to improved treatment is to be encouraged and commended. Three experimental groups consisting of 40 rats each were formed. Using microsurgical technique, total laminectomy between T5 and T10 was performed. Spinal cord injury was achieved with an epidural aneurysm clip, and pharmacological treatment immediate after the injury was performed by injecting indomethacin intraperitoneally (i.p.) at a dose of 3 mg/kg to indomethacin-treated group. The three main groups were divided into subgroups of 8 rats each. It was planned to stop the biochemical reactions at a different time in each of these subgroups, by the application of liquid nitrogen to the spinal cord and paravertebral structures at the end of the 1st, 15th, 30th, 60th, and 90th minutes. All the spinal cords were removed and protected from further reactions by immersing in the liquid nitrogen tank. The lipid peroxidation levels were assessed by determining thiobarbituric acid reactive substances formation. The results of the study showed that the administration of 3 mg/kg indomethacin immediately after spinal cord injury induces lipid peroxidation to a significant degree (p<0.05 one-way ANOVA and Tukey HSD tests) when compared to the saline-treated group. This result suggests that early posttraumatic indomethacin treatment may be harmful in spinal cord injury.  相似文献   
62.
Background: To our knowledge, there is no study comparing Ponto Plus® (Oticon Medical AB, Askim, Sweden) and Baha® 5 (Cochlear Bone Anchored Solutions AG, Mölnlycke, Sweden) available in the literature.

Aims/objectives: The primary aim was to compare the performance of the Baha 5 with the Ponto Plus device in terms of speech understanding in quiet and in noise. In addition, to determine statistically whether or not the difference between the abutment systems created any variation in terms of skin reaction.

Materials and methods: Twenty bone-anchored hearing instrument users, ten in each group, were evaluated for speech understanding in quiet and several signal-to-noise ratios using the Turkish Matrix Test in a two-speaker setup. The Holger classifications were also reviewed to determine adverse skin reactions.

Results: It was revealed that the hearing results of both devices were similar and, when the skin reactions were compared, there was no statistically significant difference between the two-implant systems.

Conclusions and significance: Because of the similar results of the groups, it can be interpreted as the key different device features such as the size, weight, colour alternatives, and the ease of use of the devices might be important in terms of device preference.  相似文献   
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Miliary tuberculosis is caused by the hematogenous spread of Mycobacterium tuberculosis and consists of 1.5% of all tuberculosis cases. It is seen mostly in infants because of the immature immune system, and central nervous system CNS involvement is not rare. Tuberculomas are rarely seen in the localized form of CNS tuberculosis, and only 4% are localized in the brain stem. We report a 4.5-month-old infant who deteriorated during follow-up with the diagnosis of cytomegalovirus pneumonia, and afterwards received the diagnosis of miliary tuberculosis. Although the baby had no neurologic abnormality and cerebrospinal fluid findings were normal, cranial MRI revealed contrast enhanced nodular lesions in pons, cerebellum, and right parietal region. The case is presented to intensify the importance of CNS investigation even if the patient with miliary tuberculosis has no neurologic finding.  相似文献   
65.
BACKGROUND: Laparoscopic surgical interventions are being used in trauma patients for diagnostic and therapeutic purposes, but there are limited studies on this subject. The effect of pneumoperitoneum during intra-abdominal hemorrhage has not been elucidated. The aim of this study was to investigate the hemodynamic, respiratory, and renal effects of pneumoperitoneum in the splenic injury/ hemorrhagic shock model in rats. MATERIAL AND METHODS: In this study, 80 anesthetized Wistar male rats (294.5 +/- 31.2 g) were randomized into 2 main groups: nontraumatized (group A) and traumatized (group B). After initial preparation and monitoring, each group was divided according to the degree of pneumoperitoneum. The nontraumatized subgroups were A1, sham-operated; A2, 4-8 mm Hg; A3, 9-13 mm Hg; and A4, 14-18 mm Hg. The traumatized subgroups were B1, splenic injury without pneumoperitoneum; B2, B3, and B4, splenic injury with pneumoperitoneum at 4-8 mm Hg, 9-13 mm Hg, and 14-18 mm Hg, respectively. Mean arterial pressure, heart rate, and respiratory rate were monitored continuously. Blood samples were obtained for hemoglobin, hematocrit, arterial blood gases, and biochemical analyses. Twenty-four hour urine output was collected. RESULTS: In group B4, pH, pCO2, and HCO3 levels were lower than in all other groups, while pCO2 and base deficit levels were significantly higher (P < 0.05). Both blood and urine analysis results showed that 24-hour urine output and the glomerular filtration rate of groups A4 and B4 were significantly lower (P < 0.05), while urinary osmolarity and fractional sodium excretion levels were significantly higher (P < 0.05). CONCLUSION: High-pressure pneumoperitoneum in splenically traumatized rats amplifies acidosis, decreases urine output, decreases glomerular filtration rate, and increases urinary osmolarity and fractional sodium excretion significantly.  相似文献   
66.
Nitric oxide (NO) is an important messenger molecule with a wide range of actions in virtually all cell systems and organs. In kidneys it participates in glomerular and medullary hemodynamics, tubuloglomerular feed-back, renin secretion, and extracellular fluid balance. Although the role of NO in regulating renal function in adults is well-established, it has recently been suggested that NO has a more critical role in maintaining basal renal blood flow and glomerular filtration rate (GFR) in the developing kidney. NO is rapidly metabolized to the stable end products nitrite and nitrate, which are more slowly excreted into the urine. Thus these metabolites can be recommended as useful markers of endogenous NO synthase activity, despite limited data about age-related changes in in-vivo NO production. The aims of this study were to determine age-related normal reference values of serum and urinary NO metabolites and to assess the probable relationship between these metabolites and the GFR. Normal levels of NO end products in blood and urine of 296 healthy children (117 female, 179 male) between the ages of 0 and 16 were investigated, as was whether these values change with age. Serum and urinary nitrate levels did not differ according to sex. Serum nitrate levels are higher in younger children, especially in the newborn period, and decrease with age. Nitrate levels in urine are higher in younger children with a peak in infancy (1 month to 1 year) and decrease with age. It was demonstrated that this decrease in serum and urinary nitrate levels with age parallels the increase in GFR. In conclusion, urinary NO products may be an indirect marker of serum NO levels and NO might have an important regulatory function both in the maintenance of renal function and in the maturation of the developing kidneys.  相似文献   
67.
OBJECTIVE: The aim of this study was to assess the effect of immunoregulatory cytokine interleukin-10 (IL-10) gene therapy on pancreas tissue rejection in a heterotopic pancreas transplantation model. BACKGROUND: Modulation of inflammatory responses by anti-inflammatory cytokines (e.g., IL-10) has been suggested to minimize organ rejection. In this context, modulation of cytokines using gene therapy could be a new therapeutic modality in preventing organ rejection. METHODS: The study was performed using male inbred Wistar rats as recipients and Sprague-Dawley rats as donors. 24 h before transplantation, groups of rats, named IL-10 (n = 20) and green fluorescent protein (GFP, n = 20), were injected with viral vectors Ad5CMVhIL10 or Ad5CMVGFP. Sham-operated rats (n = 20) underwent saline injection only before transplantation. The pancreatic tissue from each of these donor rats was subsequently transplanted into the corresponding groups of streptozotocin-induced diabetic recipient rats. Recipients were thus transfected with either IL-10 (n = 20), GFP-only carrying viral vectors (n = 20) or no viral vectors (normal saline, n = 20). A selected number of animals from each recipient group (n = 5) was sacrificed at weekly intervals for 3 weeks and some were further followed up to 12 weeks before sacrifice. Histological assessment of the pancreatic tissue was made based on rejection and GFP expression. Blood glucose levels were checked daily in all groups until sacrifice. Upon sacrifice, serum cytokine and insulin levels were measured. Histopathological correlations between blood glucose levels, serum insulin levels and serum IL-10 levels were made. RESULTS: IL-10 gene therapy significantly attenuated pancreas rejection compared to controls, provided more normal blood glucose levels and elevated plasma insulin levels. Upon assumed natural deactivation of transferred viruses after 4 weeks, differences between groups in terms of rejection, blood glucose and insulin levels disappeared. CONCLUSION: These findings suggest that IL-10 gene therapy significantly reduced pancreas rejection.  相似文献   
68.
OBJECTIVES: The aim of this study was to investigate the effects of environmental light-dark changes on the outcome of mild traumatic brain injury (MTBI) using an experimental rodent model. The functions of endogenous and exogenous melatonin on the outcome of injury were also investigated METHODS: Mild traumatic brain injury was experimentally induced in 56 male Sprague-Dawley rats using a weight-drop device. Animals were divided into four groups of 14 each as follows: (i) sham-operated (trauma only, normal day-night cycle), (ii) treated with melatonin (trauma+melatonin, normal day-night cycle), (iii) darkness-induced (trauma+48 h constant dark), and (iv) treated with melatonin and darkness-induced (trauma+48 h constant dark+melatonin). Melatonin (50 mg/kg) was administered, intraperitoneally, immediately after trauma. EEG recordings were taken at three time periods (pretrauma, immediately after trauma, and 48 h after trauma). Motor functions were tested pretrauma, 24 and 48 h post-trauma. Serum melatonin levels were determined pretrauma and 48 h post-trauma. Tissue samples from right frontal area were taken 48 h after trauma for light and electron microscopic examinations. CONCLUSION: Following MTBI light deprivation alone and light deprivation in combination with exogenously administered melatonin indicated significant neuroprotective effects. Although there may be other important pathways, darkness-induced elevation in endogenous melatonin secretion appears to play an important role in this neuroprotective outcome.  相似文献   
69.
70.
Ataç A  Guven T  Uçar M  Kir T 《Military medicine》2005,170(7):566-571
OBJECTIVE: To examine the opinions and the self-reported behaviors of physicians regarding the issues of informed consent and refusing treatment. DESIGN: This study was performed between July and September 2003, with 51 physicians selected by simple random sampling. The data were collected by using a questionnaire. SETTING: A training hospital of medicine faculty. PARTICIPANTS: Fifty-one clinicians working in the branches of internal medicine and surgery. RESULTS: Although the majority (80.4%) of the participants think that information about diagnosis and treatment should always be disclosed to patients, 60.8% reported that they always disclose information about the diagnosis and 49% did the same for information about treatment. A total of 84.3% think that patients' consent should always be obtained before diagnostic and therapeutic procedures, whereas 47% reported that they always obtain consent in their clinical practice. It was also seen that physicians have doubts concerning the comprehension of the information they disclose to their patients. In addition, most (86.3%) of the participants think that a competent patient always has the right to refuse treatment, regardless of the disease and the outcomes. CONCLUSIONS: Although opinions favoring the duties implied by informed consent are in the majority, these do not always reflect the behaviors in daily clinical practice, and there may be problems in carrying out the duties implied by the elements of informed consent. Some recommendations that could be beneficial in addressing these problems are presented at the end of the study.  相似文献   
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