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81.
OBJECTIVE: The aim of this study was to evaluate the tear clearance in patients with dry eye syndrome using quantitative lacrimal scintigraphy. MATERIALS AND METHODS: We investigated 21 patients (42 eyes; 18 women, 3 men; mean age, 63.19 +/- 13.33 years) with dry eye syndrome. Additionally, for the sake of comparison, 12 normal subjects of the same age group (24 eyes; 10 women, 2 men; mean age, 68.25 +/- 2.63 years) were included. Lacrimal scintigraphy, Schirmer-1 test, BUT, and rose bengal ocular surface vital staining were performed in these cases. RESULTS: According to the results of lacrimal scintigraphy, the mean value of T 1/2 was 4.16 +/- 1.22 minutes and the mean value of RI was 14.15% +/- 2.30% in normal subjects. However, in patients with dry eye syndrome, these values were 20.59 +/- 1.97 minutes and 55.64% +/- 6.90%, respectively. Consistent with the results of ophthalmologic tests, the mean Schirmer-1 value was 12.46 +/- 2.10 mm, the mean value of BUT was 14.36 +/- 3.40 seconds, and the mean staining value of the rose bengal was 1.98 +/- 0.80 in normal subjects, whereas these values were 1.36 +/- 0.49 mm, 5.46 +/- 1.33 seconds, 6.62 +/- 0.86, respectively, in patients with dry eye syndrome. When we compared the results of lacrimal scintigraphy and the results of ophthalmologic tests, an inverse correlation was noted between both the T1/2 and RI values and both the Schirmer-1 and BUT values in all subjects (p < 0.001). However, there was a greater positive correlation between the rose bengal ocular surface staining value and both the T1/2 and RI values in all cases (p < 0.001). CONCLUSION: In the current study, it was concluded that although the lacrimal drainage system was normal, tear clearance was significantly delayed in dry eye patients. With this study, we have shown that quantitative lacrimal scintigraphy, which is an objective, practical, and noninvasive method, appears to be useful for the assessment of the tear clearance in patients with dry eye syndrome.  相似文献   
82.
Lymphadenectomy has been a matter of interest for years because of the increased morbidity rates in gynecological cancers due to the procedure itself and because the procedure requires experience. Although a number of alternative methods have been developed to find out the prevalence of gynecological cancers, dissection and histopathological evaluation of lymph nodes is still the gold standard in detecting disease. Even though there are opposing views regarding this approach, since the morbidity rate has decreased over the years many studies in the literature report that lymphadenectomy has prognostic and therapeutic value. Its contribution to survival can be attributed both to its being determinant in postoperative treatment modifications and to debulking and lymphadenectomy itself. In order to reap the prognostic and therapeutic benefit expected from lymphadenectomy, a sufficient number of lymph nodes must be dissected. Surgical experience is important both for the procedure itself and to reduce the morbidity due to the procedure. This study discusses the prognostic and therapeutic importance of lymphadenectomy in ovarian, endometrial, cervical and vulvar cancers.  相似文献   
83.
Solitary neurofibroma unassociated with neurofibromatosis type I (NFI) arising within the scrotum is an extremely rare benign tumor. There are 8 cases reported in the literature with only 1 that occurred in childhood. In the current report the authors describe an additional adolescent patient, the second case encountered in childhood and the ninth case reported in the literature, together with a review of the related articles.  相似文献   
84.
85.
OBJECTIVE: To determine the neural substrates of phonic tics in Tourette syndrome (TS) using functional magnetic resonance imaging (fMRI) and compare with a proposed tic-generating network (TGN). PATIENTS: One with TS and one normal control. METHODS: fMRI scans were obtained on the TS patient during which numerous unsuppressed phonic tics occurred and, along with the scanner noise, were recorded on audiotape. The control underwent the same functional MRI sequence but mimicked the tics within predetermined, on-off time blocks. Fuzzy clustering (FC) methods were used to generate the activation maps. RESULTS: The TS patient and control showed fMRI activation in the left middle frontal gyrus and right precentral gyrus. The TS patient also had activity in the caudate nucleus, cingulate gyrus, cuneus, left angular gyrus, left inferior parietal gyrus, and occipital gyri. CONCLUSIONS: fMRI, using an FC analysis, is a viable technique for studying TS patients with phonic tics. These results give further support to the hypothesis of a tic-generating circuit model. Further studies are required to confirm our data.  相似文献   
86.
A 4 1/2-year-old boy with signs and symptoms of spastic paraparesis and dyspnea is presented. Biotinidase deficiency was considered and was confirmed by both urine organic acid analysis and biotinidase activity measurement. The child recovered gradually on biotin therapy. Because other systemic signs and symptoms of the disease might not be present initially or might develop later, biotinidase deficiency should be considered in the differential diagnosis of a child presenting with acute or subacute spastic paraparesis.  相似文献   
87.
Cranial computed tomography in purulent meningitis of childhood   总被引:3,自引:0,他引:3  
The cranial computed tomography (CT) findings of 48 children with purulent meningitis were examined, prospectively, to determine the importance of cranial CT findings on the prognosis of childhood meningitis, in a developing country. The age of children ranged from 2 months to 13 years. Of 48 patients, 29 (60.5%) survived without sequelae, 13 (27%) survived with sequelae, and six (12.5%) died. Cranial CT was normal in 21 (43%) patients of 48 children with meningitis at admission. Abnormal CT findings were detected in 10, 11, and 6 children in the groups of survived without sequelae, survived with sequelae, and deaths, respectively, at admission (p <.05) We found that CT scan results were correlated with neurological signs (p <.05). At least one or more cranial CTs were was re-taken in children in whom the first CT revealed abnormal findings; we did not find a statistically significant difference for the follow-up CT findings between the groups (p >.05). Hydrocephalus and subdural effusion were the commonest abnormal CT findings. In conclusion, our findings showed that cranial CT may safely be used to detect intracranial complications of meningitis in childhood and the ratio of sequelae and death were more common in children with abnormal cranial CT than those of normal cranial CT findings. Additionally, there was a positive correlation between CT scan results and neurological signs.  相似文献   
88.
Ekici S  Saraydin D 《Drug delivery》2004,11(6):381-388
We prepared new ternary interpenetrating polymeric networks (IPN) systems containing chitosan, poly(N-vinylpyrrolidone) and poly(acrylamide) polymers. IPNs were synthesized by radical polymerization of acrylamide monomers in presence of glutaraldehyde (G) and N,N'-methylenebisacrylamide as crosslinkers and the other polymers. These IPNs were named as C-P-A. Glutaraldehyde were used in different concentration to control the network porous of IPNs. Spectroscopic and thermal analyses of these cylindrical shaped IPNs were made with fourier transform infrared spectroscopy analysis, thermogravimetric analysis, and thermomechanical analysis. Swelling studies of IPNs were carried out at pH 1.1 and pH 7.4 at 37°C. The swelling and diffusion parameters of IPNs in these solutions were calculated. Amoxicillin as a bioactive species was entrapped to the IPNs during synthesis. In vitro release kinetics of IPNs were investigated. The experimental data of swelling and release studies suggest clearly that the swelling and release process obeys second-order kinetics. The release of the entrapped bioactive species from IPNs depends on the degree of crosslinking of the polymer and pH of the medium at body temperature. We observed that amoxicillin release at pH 1.1 was higher than at pH 7.4. As a result, IPNs-based chitosan with different cross-linker concentration could be promising candidates for formulation in oral gastrointestinal delivery systems.  相似文献   
89.
The main problem after total laryngectomy is permanent loss of voice. Current methods of vocal rehabilitation after total laryngectomy include development of esophageal speech, use of artificial larynx, tracheoesophageal shunt operations and more recently surgical restoration of the voice with prosthesis. Primary voice restoration using Blom- Singer voice prosthesis after total laryngectomy and pharyngeal myotomy was performed in 187 patients between October 1992 and July 2000. There were 184 male and 3 female patients of average age 63.7 years (range 42-76). Mean follow up period was 62 months. Satisfactory speech was achieved in 156 patients (83.5%). During the follow-up period, we experienced complaints of insufficient voice in 31 (16.5%) patients, due to partial spasm in 17 and total spasm in the pharyngoesophageal segment in 14. Furthermore, 24 (12.8%) patients preferred esophageal speech or electro larynx because of low socioeconomic level. The overall success rate was 70.7%. In this study the results of the surgical technique and prosthesis insertion, as well as the associated complications and socioeconomic levels of the patients, are discussed.  相似文献   
90.
We retrospectively assessed the clinical course and outcome of left-sided endocarditis in pediatric patients to find out the prognostic significance of the presence and size of echocardiographically detected vegetations. Among the children admitted to our institution with endocarditis between January 1987 and October 1999, 16 patients (mean age 9.03 +/- 4.95 years) who met the Duke criteria for the diagnosis of infective endocarditis (IE) were included in this study. Rheumatic valvular disease was the most frequent underlying heart disease (10 patients: 62.5%). Five patients were operated at a mean of 13.9 months before endocarditis, and all had residual defects. Vegetation was detected in 11 cases (69%). Ten patients had major complications (within 2 weeks in 6 patients). Three patients developed congestive heart failure (CHF), six had intracranial and one had lower extremity emboli. Among them four were operated because of complications (CHF: 3 cases, intracranial emboli: 1 case). All the operated cases are doing well. The association between intracranial embolic events and echocardiographically detected vegetations was determined by calculating specificity (40%), sensitivity (100%), positive predictive value (50%), and negative predictive value (100%). No intracranial embolism occurred in patients without vegetations. All vegetations were < or = 6 mm in patients with systemic embolism. There were four deaths, three of which were because of intracranial embolism. This study suggests that intracranial emboli have a major risk of mortality in left-sided endocarditis. The larger size of the vegetation is not a predictor of complications; furthermore, the absence of vegetations predicts that the patient is safe from embolic events. Therefore all patients with left-sided IE should be considered for earlier surgical intervention.  相似文献   
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