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71.
Occupational exposure to wood dust is associated with the occurrence of nasal cancer. In this study, we investigated micronuclei and nuclear changes (NCs: binucleates, karyorrhexis, karyolysis, and the "broken egg" effect) in exfoliated buccal cells of 20 workers exposed to wood dust and 20 age- and sex-matched controls. Micronucleus frequency and the frequency of each of the NCs were significantly higher for wood workers than controls (P < 0.01). Cigarette smoking was associated with increased frequencies of micronuclei and NCs in the buccal mucosa epithelium cells of both the control and exposed groups. Our findings indicate that buccal cells of wood workers display increased levels of genotoxicity and toxicity, and that these biomarker responses may be related to the increased cancer risk among wood workers.  相似文献   
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73.
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   
74.
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   
75.
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   
76.
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   
77.
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   
78.
79.
The seroprevalence of Helicobacter pylori and nitric oxide in acne rosacea   总被引:5,自引:0,他引:5  
BACKGROUND: Acne rosacea is a dermatosis with unknown etiology. Some studies have reported a high prevalence of Helicobacter pylori infection in acne rosacea. Other studies have reported a decrease in the severity of the lesions of acne rosacea after eradication of H. pylori. H. pylori is a Gram-negative bacterium which colonizes the gastric mucosa and increases the synthesis of oxygen radicals, such as superoxide and proinflammatory cytokines. These cytokines have been demonstrated to stimulate the synthesis of the inflammatory species nitric oxide (NO). In this study, we examined the role of NO in the possible effect of H. pylori in acne rosacea. METHODS: Thirty-three acne rosacea patients were included in the study and the control group comprised 20 healthy individuals. The levels of immunoglobulin G antibodies against H. pylori in the serum samples were measured using the enzyme-linked immunoabsorbent assay method. Measurement of nitrate was performed using chemiluminescence in accordance with the method described by Braman and Hendrix (Braman RS, Hendrix SA. Nanogram nitrite and nitrate determination in environmental and biological materials by vanadium(iii) reduction with chemiluminescence detection. Anal Chem 1989; 61: 2715-2718). For statistical analysis, the t-test was used. RESULTS: The seropositivity of H. pylori in acne rosacea patients was found to be high; however, the serum nitrate levels were found to be normal. CONCLUSIONS: The results of the study indicate that the inflammatory species NO, which has been hypothesized to be associated with H. pylori, has no role in the inflammatory mechanism of acne rosacea.  相似文献   
80.
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