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101.
Mehmet Ctrk Cosar Batman Gamze Men Murvet Tuncel Orhan Zleloglu 《Clinical & experimental optometry》2007,90(5):367-370
Purpose: To report a case of Alport’s syndrome and to present electronmicroscopic examination findings of the anterior lens capsule of this patient. Method: A 21‐year‐old man was referred for low visual acuity and retinal pigment epithelial changes in the left eye. The patient and his relatives underwent detailed ophthalmological examination, including electrophysiological testing. The patient also underwent electronmicroscopic examination of the anterior lens capsule. Results: His visual acuity was 6/18 OD and 6/15 OS. Anterior lenticonus and subcapsular opacities were observed in the left eye. Cataract extraction by phacoemulsification with intraocular lens implantation was performed for his poor visual performance. During the capsulorhexis, the remarkably thin and fragile anterior capsule was noted and removed. Ultrastructural analysis of the anterior lens capsule showed a thinner central zone compared with the periphery. Conclusions: The course of Alport’s syndrome can be ameliorated by early diagnosis. Therefore, the ophthalmological examination of a patient with anterior lenticonus must be combined with a detailed medical evaluation. Ultrastructural analysis of the lens capsule can support the diagnosis of Alport’s syndrome. 相似文献
102.
Growth retardation is a clinical feature of patients with thalassemia major, and endocrine studies have frequently revealed the presence of normal growth hormone (GH) secretion. The present study was undertaken in 14 prepubertal thalassemic children (9 males and 5 females), aged 2(2/12) to 10(3/12) years, with the aim of evaluating GH response to i.v. arginine, oral L-dopa stimulation and insulin-like growth factor-1 (IGF-1) levels. Eleven patients had peak serum GH levels less than 7 ng/ml and two patients had peak serum GH levels of 7-10 ng/ml with arginine. Similarly, 10 patients had peak levels less than 7 ng/ml and one patient had a peak level of 7-10 ng/ml with L-dopa. Thus, nine of the patients had GH deficiency and two had partial GH deficiency. Three patients had elevated basal GH values. The serum IGF-1 levels in the patients were not statistically different from the levels in the controls, but three patients had low IGF-1 values. These findings suggest a defect in the regulatory mechanisms of GH secretion. 相似文献
103.
Adanali G Erdogan B Turegun M Tuncel A Gencaga S Albayrak L 《Aesthetic plastic surgery》2002,26(5):340-344
Although there is a controversy about success and failure of autologous fat tissue transfers, it is a widely accepted method for soft tissue augmentation and is performed by many plastic surgeons as well as dermatologists all around the world. Its advantages are that it does not cause reactions, its absorption rates have been reduced by increased knowledge, experience, and techniques, it can yield good, long-term results, and there are now preservation techniques that allow reinjections when necessary. However, no single ideal technique has been determined. In this paper a new, simple, T-shaped adaptor for easy, quick, and efficient fat harvesting during liposuction is described. This study not only describes the clinical use of the adaptor, but also histologically examines its effects on fat cells under various vacuum pressures (-250 mmHg, -500 mmHg, -700 mmHg). The study shows that the cell structure of fat tissue harvested under medium power (with vacuum pressures of -250 mmHg and -500 mmHg) is not disrupted, while that of tissue harvested with a vacuum pressure of -700 mmHg was traumatized and occasional cell wall fragmentation occurred. In conclusion, it is shown that the T-shaped adaptor allows harvesting of the desired amount of fat tissue without causing trauma to fat cells when it is used with medium-power suction. 相似文献
104.
In the past decade, the number of patients demanding rhinoplasty has increased, and this has increased the use of grafts.
Although different materials are used as grafts, cartilage is the most popular one. In secondary rhinoplasties the need for
cartilage is very frequent. The most suitable cartilage grafts are the ones extracted during primary rhinoplasty. These grafts
are disposed of after the operation and in a secondary operation, grafts are obtained from a new donor site.
In our department, the surplus cartilages obtained during primary rhinoplasties of the patients who are thought to be probable
secondary rhinoplasty candidates are stored in a postauricular pocket after their volumes are measured and marked down. In
the secondary operations the volume of the grafts are measured again and the grafts are used.
We have found out that there is no significant difference between the initial and secondary volumes of lower lateral cartilages
(3.6% of initial volume is lost), but the difference between the initial and secondary volumes of septal cartilages is significant
(6.9% of initial volume is lost), and the stored cartilages are sufficient qualitatively and quantitatively for the secondary
rhinoplasties. 相似文献
105.
Adanali G Senen D Turegun M Tuncel A Erdogan B Albayrak L 《Aesthetic plastic surgery》2002,26(6):465-469
Androgenic alopecia is a serious problem for a large proportion of the population, especially males, and causes them to seek medical help. Many methods have been described for treatment of androgenic alopesia. Among them are punch grafts, strip grafts, scalp grafts, scalp reductions, tissue expanders, and flap combinations, and hair transplantations with minigrafts and micrografts. The latter has become popular in the last two to three decades and has been investigated extensively. Improvements in hair replacement with minigrafts and micrografts may allow an ideal result with a nearly normal appearance. However, hair replacement with these grafts has important disadvantages. It requires a long operational time and only a limited number of grafts can be placed in one session. In this study, we investigated morphological structures of micrografts stored at 4 degrees C and those stored at -20 degrees C. We found that morphological structures of the grafts stored at 4 degrees C started to be impaired in the fifth day, but that the morphological structures of the grafts stored at -20 degrees C remained unaltered for 15 days. If this method is put into practice, the use of minigrafts and micrografts available will not only obviate the second graft harvesting, but also allow reconstruction of a large area in a short period of time. 相似文献
106.
As a potent vasoconstrictor, epinephrine is used ubiquitously in plastic surgery. It is typically delivered subcutaneously in very low concentrations over a brief time interval. We are aware of no reports describing the long-term release of epinephrine as an independent agent to the soft tissues for the purpose of causing prolonged local vasoconstriction. This study was designed to address two goals: first, to investigate the effect of long-term local release of epinephrine from a drug delivery system on rat abdominal skin vasculature; secondly, to evaluate the pharmacological properties of this drug delivery system (DDS). Thirty male Sprague-Dawley rats, weighing 300-400 g, were included in the study. Animals were subdivided into two groups of 15 each. Group A (control group) and Group B (experimental group) were treated with saline and epinephrine-loaded microspheres (msps), respectively. The manufacturing process and formulation studies of the DDS are described. In vivo assays revealed a 7-day sustained release of epinephrine. After 7 days, neither residual nor supraphysiologic release of epinephrine was shown with high-performance liquid chromatography (HPLC). Histological studies with hematoxylin-eosin and periodic acid Schiff revealed a statistically significant increase in number of vessels as well as their diameter and wall thickness (P <0.05). Epinephrine release via this msp/DDS predictably induces local vasoconstriction over a time sequence known to be optimally associated with hypoxia and promotion of vascular augmentation. This model can be valuable in sustaining hemostasis during long-lasting (more than a few hours) surgical procedures by its long-acting vasoconstructive effect. The system's ability to intentionally cause vascular augmentation also bodes great potential in flap and graft surgery. 相似文献
107.
Antioxidant actions and early ultrastructural findings of thiopental and propofol in experimental spinal cord injury 总被引:1,自引:0,他引:1
Kaptanoglu E Sen S Beskonakli E Surucu HS Tuncel M Kilinc K Taskin Y 《Journal of neurosurgical anesthesiology》2002,14(2):114-122
Thiopental and propofol are effective antioxidant agents. The current study was undertaken to examine the neuroprotective effects of a single intraperitoneal dose of thiopental and propofol. Effects of the drugs were evaluated by lipid peroxidation and ultrastructural findings. Fifty male Wistar rats were divided into five groups. Group 1 was the control group. Rats underwent laminectomy only, and nontraumatized spinal cord samples were obtained 1 hour after surgical intervention. All other rats sustained a 50-g/cm contusion injury by the weight drop technique. Group 2 rats underwent spinal cord injury alone, group 3 rats received 1 mL intralipid solution intraperitoneally immediately after trauma as the vehicle group, group 4 rats received a 15-mg/kg single dose of thiopental, and group 5 rats received a 40-mg/kg single dose of propofol intraperitoneally following the trauma. Samples from groups 2, 3, 4, and 5 were obtained 1 hour after injury. Lipid peroxidation was determined by measuring the concentration of malondialdehyde in the spinal cord tissue. The ultrastructure of the spinal cord was determined by electron microscopy. The contusion injury was associated with a rise in lipid peroxidation. Compared with the trauma group there was significant attenuation in lipid peroxidation of groups 4 and 5. Ultrastructural findings showed that the rats of group 4 sustained minor damage after spinal cord injury, but there was more evident damage in group 5 rats. These results indicate that thiopental decreases lipid peroxidation and improves ultrastructure, whereas propofol decreases lipid peroxidation without improving ultrastructure 1 hour after spinal cord injury in rats. 相似文献
108.
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
109.
Tali ET Ercan N Krumina G Rudwan M Mironov A Zeng QY Jinkins JR 《Investigative radiology》2002,37(3):152-159
RATIONALE AND OBJECTIVES: This cooperative multicenter human study was designed to evaluate the safety, magnetic resonance (MR) imaging characteristics, and clinical response to a single gadolinium contrast agent: gadopentetate dimeglumine. MATERIAL AND METHODS: Ninety-five patients (age range: 1 month to 78 years; sex: 50 males, 45 females) were included in this prospective study. The patients presented clinically with a variety of cranial or spinal signs and symptoms for which an intrathecal contrast myelogram or cisternogram was requested by clinical staff. Via lumbar puncture (20-25 g needle), 3 to 5 mL/ml of cerebrospinal fluid were withdrawn and mixed with a single volume of 0.5 (n = 63), 0.7 (n = 13), 0.8 (n = 12), or 1.0 (n = 7) cc/mL of gadopentetate dimeglumine (Magnevist; Schering, Berlin, Germany). This was then injected into the subarachnoid space, and the needle was removed. Immediate and delayed (up to 96 hours) T1- and T2-weighted MR imaging was performed on super conductive, high-field (1.0-1.5 tesla) imaging units in two or three planes. All patients were hospitalized for an observation period of 24 hours following the procedure, and follow-up neurologic examinations were performed serially for 6 to 12 months afterward. RESULTS: No patient manifested gross behavioral changes, neurologic alterations, or seizure activity at any time following the procedure. Nineteen patients (20%) experienced postural postlumbar puncture headache, six patients had nausea (6%), and two patients had episodes of vomiting (2%), all which resolved within the first 24 hours of the lumbar puncture with conservative bed rest. CONCLUSION: This cooperative study demonstrates the general safety and feasibility of low dose (0.5-1.0 mL/ml) intrathecal gadopentetate dimeglumine administration. The potential useful clinical applications include the evaluation of obstructions and communications of the various subarachnoid spaces, spontaneous or traumatic/postsurgical craniospinal cerebrospinal fluid leaks, and subarachnoid space CSF flow and parenchymal CNS interstitial diffusion dynamics. This worldwide cooperative study seeks to progressively perform human studies for further definitive evaluation of the practical clinical applications, of the relationship of this technique to other imaging studies and modalities, and the long-term safety of the procedure in a larger number of subjects. 相似文献
110.