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71.
Nitric oxide levels in rat cortex,hippocampus, cerebellum,and brainstem after impact acceleration head injury 总被引:2,自引:0,他引:2
Tuzgen S Tanriover N Uzan M Tureci E Tanriverdi T Gumustas K Kuday C 《Neurological research》2003,25(1):31-34
Nitric oxide (NO) is a potential mediator of secondary brain injury in the settings of cerebral ischemia and inflammation. Traumatic brain injury (TBI) alters the levels of stable end products of NO metabolism. We investigated these changes and attempted to identify brain regions that were unique with regard to NO production in the period immediately after TBI. The experiment involved assaying nitrite-nitrate concentrations in the rat cortex, cerebellum, hippocampus, and brainstem after impact-acceleration head injury. Five rats comprised the sham-operated (control) group, five sustained mild head injury (MHI), and five sustained severe head injury (SHI). There was a uniform decline in the tissue concentrations of NO metabolites in all four brain regions in both injured groups. There were no significant differences in the concentrations of NO metabolites among the various sites tested in the MHI group; however, there appeared to be a relationship between degree of decline in NO levels and amount of trauma sustained by a given region in the SHI group. In these rats, NO dropped to the lowest levels in the brain region where the direct trauma was most severe. The results suggest that nitrite-nitrate levels in these four brain regions fall below normal in the first 5 min after impact trauma. This decrease may, in part, be related to reduced activity of all nitric oxide synthase isoforms, which would cause a drop in the levels of NO metabolites. We believe that this decline may be linked to, and may even cause, the global decrease in cerebral blood flow that occurs in the initial stages of TBI. 相似文献
72.
Systemic amyloidosis is an unusual cause of generalized massive lymphadenopathy. In such cases the clinical picture may mimic lymphoma. We report a case of generalized massive lymphadenopathy caused by amyloidosis. The 55-year old female patient was admitted to our hospital with dyspnea and edema in the lower extremities. These were diminished breath sounds with bilateral basal congestion hepatosplenomegaly and generalized massive lymphadenopathy in axillary, cervical, and inguinal areas. The diagnosis was made by excisional biopsy of one of the involved lymph nodes. Amyloidosis (AL type) was shown and treatment with melphalan and prednisone was initiated. Unfortunately the patient died after 51 days in hospital. 相似文献
73.
Kücüködük S Sezer T Yildiran A Albayrak D 《Scandinavian journal of infectious diseases》2002,34(12):893-897
A randomized, double-blinded, placebo-controlled trial was conducted of early administration of recombinant granulocyte colony-stimulating factor (rGCSF) to 40 non-neutropenic, preterm infants between 33 and 36 weeks of gestational age with the diagnosis of presumed sepsis. The treatment group (n = 20) received 5 microg/kg per day of intravenous rGCSF once daily for 3 d and the control group (n = 20) received the same volume of physiological serum. Immediately before the first dose and on the 4th day, plasma levels of GCSF and tumour necrosis factor-alpha (TNF-alpha), absolute neutrophil counts (ANC), immature neutrophil count (INC), immature/total neutrophil (I/T) ratios and platelet counts were determined. At study entry, the plasma GCSF and TNF-alpha levels were similar. On day 4, there was no significant change in GCSF levels in either groups, whereas there was a significant decrease in TNF-alpha levels in the treatment group. ANC and INC of the treatment group also increased significantly. The I/T ratio continued at the same level in the treatment group, but decreased significantly on days 4 and 7 day in the control group. The length of time on the neonatal intensive care unit (NICU) was significantly shorter in the treatment group. In conclusion, early administration of 3 daily doses of rGCSF (5 microg/kg per day) to non-neutropenic, preterm infants who had presumed sepsis increased circulating ANC and INC, decreased plasma TNF-alpha levels and shortened the length of time on the NICU. 相似文献
74.
Proprioception of the ankle: a comparison between female teenaged gymnasts and controls 总被引:2,自引:0,他引:2
Aydin T Yildiz Y Yildiz C Atesalp S Kalyon TA 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2002,23(2):123-129
Proprioceptive mechanisms appear to play a role in stabilizing the joints and may serve as a means for interplay between static stabilizers and dynamic muscular restraints. The purpose of our study was to investigate whether or not gymnastic training has any effect on the balance and on proprioception in an ankle, as seen in gymnasts and in nongymnasts. We evaluated the proprioceptive ability of the ankle using four different tests (a one-leg-standing test, a single-limb-hopping test, an active angle-reproduction test, and a passive angle-reproduction test). Proprioception of the ankle was measured in 40 subjects who were assigned to two experimental groups. Group 1 (n: 20) were healthy control subjects, and group 2 (n: 20) were teenaged female gymnasts. The sense of position of a joint was actively measured using a Cybex NORMTM isokinetic dynamometer and measured passively with a proprioception-testing device. A Mann-Whitney U test was used to compare mean values of the gymnasts to the controls. Results revealed statistically significant differences (p<0.05) between two groups. We found no statistically significant differences between the dominant and nondominant ankle in volunteers or in gymnasts, in all tests. The results of this study suggest that gymnastic training has a positive influence on sense of position of the ankle joint and on balance, in addition to increasing muscle tone. 相似文献
75.
Oguzhan Deyneli Dilek Yavuz Ayliz Velioglu Hasan Cacina Nihal Aksoy Goncagül Haklar Yavuz Taga Sema Akalin 《Journal of the renin-angiotensin-aldosterone system》2006,7(2):98-103
Angiotensin-converting enzyme (ACE) inhibitors may reduce urinary albumin excretion (UAE) by decreasing glomerular pressure and increasing glomerular charge selectivity through preservation of glycosaminoglycans. The effect of Angiotensin II antagonism on glomerular charge selectivity remains to be determined. The aim of this study was to compare the effects of an AT1 blocker losartan and an ACE inhibitor (ACE-I) enalapril on UAE, extracellular matrix proteins, glycosaminoglycan excretion (UGAG) and red blood cell anionic charge (RBCCh) which are the indirect markers of glomerular basement membrane anionic content in hypertensive Type 2 diabetic patients. Twenty-four patients were randomised into two groups and received either enalapril (520 mg/d) or losartan (50100 mg/d). All parameters were measured at baseline and after six months of treatment. At the end of six months, systolic and diastolic blood pressures (BP), UAE rates, UGAG excretion and RBCCh were significantly and equally reduced in both treatment groups compared with baseline. RBCCh was negatively correlated with UAE (r=-0.57, p<0.0001) and UGAG excretion (r=-0.57, p<0.0001); UAE was correlated with UGAG excretion (r=0.58, p<0.0001). In conclusion, enalapril and losartan treatment were equally effective in reducing BP, UAE as well as UGAG excretion and preserving RBCCh in hypertensive Type 2 diabetic patients. ACE inhibition and AT1-receptor blockade may have favourable effects on preserving glomerular anionic content in hypertensive diabetic patients. 相似文献
76.
Mustafa Cenk Ecevit Taner Kemal Erdag Ataman Guneri Sulen Sarıoglu Enis Alpin Guneri 《European archives of oto-rhino-laryngology》2006,263(5):469-472
Hypopharyngeal schwannoma is quite rare, with only nine cases presented in the literature to our knowledge. The presentation itself requires a distinction from malignant hypopharyngeal disease, which is usually the initial diagnosis. A transcervical approach and laryngomicrosurgery are two possible operating methods for the treatment of hypopharyngeal schwannoma. The selection of the surgical method depends on the size of the tumor. For this case, we preferred the transcervical approach without tracheotomy. In contrast to previous case reports, we were unable to trace the original nerve. 相似文献
77.
Anders Jeppsson Carlo Pellegrini Timothy O'Brien Virginia M. Miller Henry D. Tazelaar C. Burcin Taner Christopher G. A. McGregor 《Transplant international》2000,13(1):S591-S596
Experiments were designed to study whether overexpression of nitric oxide (NO) from endothelial nitric oxide synthase (eNOS) affects acute rejection. Allogenic, orthotopic single-lung transplantation was performed after transbronchial adenoviral-mediated gene transfer (3 × 108 pfu) of either of eNOS or β-galactosidase to donor lungs of rats (n = 6 each). No immunosuppression was used. After 4 days, transplanted lungs were prepared for enzyme activity, cGMP and histology. Calcium-dependent NOS activity, reflecting eNOS, was greater in eNOS-transduced lungs (587 ± 97 vs 2.1 ± 1.4 pmol/mg protein per h, P <0.001). In contrast, calcium-independent NOS activity, reflecting iNOS, was comparable. Concentrations of cGMP were higher in eNOS-transduced lungs (13.2 ± 2.3 vs 4.9 ± 0.5 pmol/mg protein). Positive immunostaining for eNOS was present in pneumocytes only in eNOS-transduced lungs. No difference in histological grade of rejection was observed. eNOS gene transfer to pulmonary allografts results in a functionally active transgene product and increased NO production. Increasing NO from eNOS does not affect histogically identified acute rejection. 相似文献
78.
Kiziltepe U Uysalel A Corapcioglu T Dalva K Akan H Akalin H 《The Annals of thoracic surgery》2001,71(2):684-693
BACKGROUND: Modified ultrafiltration (MUF) improves hemodynamics and postoperative recovery in children. Ultrafiltration (UF) may have similar benefits in adults. The purpose of this study was to investigate the effects of UF in adult patients. METHODS: A total of 40 adult patients undergoing cardiac surgery were randomized into a study group of conventional UF during bypass + venovenous MUF after bypass and a control group with no UF. Perioperative clinical variables, cytokines, and endothelin-1 levels were compared between groups. RESULTS: There was no mortality in either group. The patients in the study group had a greater rise in hematocrit (5.7% +/- 2.4% vs 1.2% +/- 1.9%, p < 0.001), hemoglobin (1.7 +/- 0.8 mg/mL vs 0.5 +/- 0.6 mg/mL, p < 0.0005), and platelet levels (27,800 +/- 29,200 vs -9,000 +/- 30,970, p < 0.001). Mean arterial blood pressure and CI increased after MUF (from 64.2 +/- 16.9 mm Hg to 72.3 +/- 14.1 mm Hg, p = 0.05, and from 2.4 +/- 0.7 to 2.8 +/- 0.6, p < 0.03, respectively). Postoperative oxygenation was better in the study group (alveolo-arterial PO2 tension gradient 74.6 +/- 43.9 mm Hg vs 107.2 +/- 27.8 mm Hg, p = 0.03). Ultrafiltration reduced postoperative bleeding (522.2 +/- 233.4 mL vs 740 +/- 198.4 mL, p < 0.003). CONCLUSIONS: A combination of conventional and modified UF is effective and safe in adult patients undergoing cardiac surgery. Ultrafiltration improved hemodynamics, hemostatic, and pulmonary functions. We recommend the use of combined UF in high-risk adult patients. 相似文献
79.
Cardiac hydatid cyst is an uncommon lesion. The infection, often acquired by children during play with infected dogs, is most
common in sheep-raising areas of the world. We report our clinical and surgical experience in the treatment of one of the
youngest reported cardiac hydatidosis patients with multivisceral involvement. 相似文献
80.
Rheumatic heart disease (RHD) continues to be a common health problem in the developing world. Although little longitudinal data are available, evidence suggests that there has been little if any decline in the occurrence of RHD over the past few decades. There are only a few population surveys available in Turkey for prevalence of RHD. This survey was undertaken to estimate its prevalence among schoolchildren and changes over the last 20 years in the capital, Ankara. In Ankara, 4,086 schoolchildren aged between six and 17 years were screened over a period four months (March 1995-June 1995) by the same pediatrician. Forty-eight percent (n = 1,945) were female and 52 percent (n = 2,141) were male. Three children out of 4,086 (0.73 per 1,000) were noted to have findings consistent with RHD. Fifteen children had an episode of rheumatic fever (RF). Cumulative prevalence rate (prevalence rate for RF history) was 3.7 per 1,000. We concluded that RHD prevalence has decreased in Ankara over the last decades. 相似文献