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961.
OBJECTIVE: The purpose of this study was to examine the changes in nitric oxide (NO) level in the nasal and paranasal sinus mucosa after exposure radiofrequency electromagnetic fields (EMF). STUDY DESIGN AND SETTING: Thirty male Sprague-Dawley rats were randomly grouped as follows: EMF group (group I; n, 10), EMF group in which melatonin received (group II; n, 10) and the control (sham operated) group (group III; n, 10). Groups I and II were exposed to a 900 MHz. Oral melatonin was given in group II. Control rats (group III) were also placed in the tube as the exposure groups, but without exposure to EMF. At the end of 2 weeks, the rats were sacrificed, and the nasal and paranasal sinus mucosa dissected. NO was measured in nasal and paranasal mucosa. RESULTS: The nasal and paranasal sinus mucosa NO levels of group I were significantly higher than those of the control group (group III) ( P < 0.05). However, there was no statistically significant difference between group II and the control group (group III) regarding NO output ( P > 0.05). CONCLUSION: Exposure to EMF released by mobile phones (900 MHz) increase NO levels in the sinus and nasal mucosa. SIGNIFICANCE: Increased NO levels may act as a defense mechanism and presumably related to tissue damage. In addition, melatonin may have beneficial effect to prevent these changes in the mucosa.  相似文献   
962.
PURPOSE: Leptin is produced primarily by adipose tissue. More recent studies have shown extra sites of leptin production in physiologic and ill human tissues. However, whether leptin originates from human corneas in infectious keratitis and keratoconus is not known. The aim of this study was to demonstrate and quantitate leptin expression in corneas with infectious keratitis and keratoconus and make comparisons to control corneas. METHODS: We examined the immunohistochemical staining of leptin in nine corneas surgically excised from patients with infectious keratitis (3 patients), keratoconus (3 patients), and donor corneas (3 patients). RESULTS: The results were analyzed using a semiquantitative scoring system of mild, moderate, and strong. Cells of the infectious keratitis group had the strongest leptin staining intensity, the control group had moderate, and the keratoconus group had mild staining intensity. The more vascular corneas in the infectious keratitis group were also associated with the greatest leptin staining. CONCLUSIONS: Our findings indicate that leptin expression was present in all three sources of corneas (infectious keratitis, keratoconus, and normal control). Quantitative scoring would imply it may play a role in infectious keratitis, although further experiments are necessary to establish any causal relationship.  相似文献   
963.
BACKGROUND: Occult cystobiliary communication (CBC) presents with biliary leakage, if the cystobiliary opening cannot be detected and repaired at operation. We investigated the clinical signs associated with the risk of occult CBC in the preoperative period by studying patients who developed biliary leakage after hydatid liver surgery. METHODS: We analyzed the records of 191 patients treated for hydatid liver cyst. Postoperative biliary leakage developed in 41 patients (21.5%). Independent predictive factors were established by logistic regression analysis using clinical parameters, whose cutoff values were determined by receiver operating characteristic (ROC) curves. RESULTS: Postoperative biliary leakage presented as external biliary fistula in 31 (75.6%) of 41 patients, as biliary peritonitis in 6 (14.6%) and as cyst cavity biliary abscess in 4 (9.8%). Independent clinical predictors of occult CBC, represented by biliary leakage, were alkaline phosphatase > 250 U/L, total bilirubin > 17.1 micromol/L, direct bilirubin > 6.8 micromol/L, gamma-glutamyl transferase > 34.5 U/L, eosinophils > 0.09 and cyst diameter > 8.5 cm. Multilocular or degenerate cysts increased the risk of biliary leakage (p = 0.012). Postoperative complication rates were 53.7% in the patients with biliary leakage, and 10.0% (p < 0.001) in those without. The mean postoperative hospital stay was longer in patients with biliary leakage (14.3 [and standard deviation {SD} 1.9] d) than in those without (7.3 [SD 2.3] d) (p < 0.001). Nineteen (61.3%) of 31 biliary fistulae closed spontaneously within 10 days. The remaining 12 (38.7%) fistulae closed within 7 days after endoscopic sphincterotomy. CONCLUSION: Factors that predict occult CBC due to hydatid liver cyst were identified. These factors should allow the likelihood of CBC to be determined and, thus, indicate the need for additional procedures during operation to prevent the complications of biliary leakage.  相似文献   
964.
965.
OBJECTIVE: Tympanostomy tube insertion is one of the most frequently performed procedures in otolaryngology. Complications, such as otorrhea, tympanosclerosis, and cholesteatoma, have been reported in the literature after its application. STUDY DESIGN: This study reports the complications encountered with 239 children (439 ears) with a follow-up of 7 to 73 months (median, 29 months) after tympanostomy tube insertion. Hearing results and middle ear pressures were compared and complications were noted in 366 ears that were available for the study. RESULTS: Otorrhea developed in 3 (0.8%) cases. Tympanosclerosis was seen in 74 (20.2%) cases. Tympanic membrane perforation, retraction pocket, granulation tissue, and atelectasis were seen in 4.6%, 5.2%, 1.1%, and 6%, respectively. No patients developed cholesteatoma after tube insertion. Hearing results were improved postoperatively in 93.4% of patients (median, 14.2 dB) and worse in 6.6% of patients (median, 8.3 dB). The average extrusion time was 7.3 months for grommet and 16.3 months for T-tubes. CONCLUSION: Multifactor etiologies show some unsolved or misunderstood underlying pathology, or unmentioned environmental factor such as atopy due to rich flora and humidity might exist to consider in the pathophysiology of the otorrhea.  相似文献   
966.
Bromocriptine therapy for macroprolactinoma induced cerebrospinal fluid (CSF) rhinorrhea in three patients. The tumor had extended well beyond the sella turcica and caused bony erosion in all the cases. All three patients responded to bromocriptine therapy rapidly. CSF fistula occurred concomitantly with the reduction of tumor size and caused meningitis in two of the patients. Withdrawal of bromocriptine resulted in cessation of the leakage. One of the patients underwent transsphenoidal repair. Two patients refused surgery. This potentially lethal complication encountered in these three cases demonstrates the need for close supervision of macro-prolactinoma patients with skull base erosion placed under bromocriptine therapy.  相似文献   
967.
Fourteen patients with cerebellar abscesses, of a total of 116 brain abscesses treated at our clinic between 1987 and 1992, were analysed retrospectively. Of 14 cases, 11 were male, 3 were female. The youngest of the cases was 7, while the oldest was 58, and average age was 32.4. Five patients were comatose on admission. Mastoiditis in 6 patients, otitis in 3 patients and pulmonary infection in 1 patient appeared to be the primary foci of infection. In 4 cases no primary infective focus was determined. The periods between the commencement of symptoms and the time of admission to the hospital were as follows: 0–2 weeks in 2 cases, 3–4 weeks in 5 cases and 4–8 weeks in 7 cases. The primary complaints on admission were headache, unconsciousness and unsteadiness. The most frequent findings were cerebellar ataxia, nystagmus and unconsciousness. The lesions in patients were established by computerized tomography. Drainage through a single burr hole was performed in all patients. Samples were taken for culture from all of the cases and microorganisms were isolated from 8 but nothing was grown in the 6 patients. The mortality was 21.4% in this series.  相似文献   
968.
Profile change in edentulous patients is a commonly observed phenomenon. It seems that the profile becomes more concave, either by loss of lip support or increased mandibular prognathism. It has been reported that the dentures migrate forward with time1; therefore, loss of lip support cannot be a significant contributor to the increased convexity of the profile. Changes that take place over a period of time in the mandibular posture have also been reported.2–6 However, those studies did not attempt to relate these changes to individual patients' characteristics. It might be possible that a particular skeletal pattern could affect the mandibular posture. Therefore, this report will deal with the influence of the skeletal pattern on mandibular prognathism as determined from cephalomet-ric films.  相似文献   
969.
OBJECTIVE: To compare pregnancy outcome in twin pregnancies with and without hydramnios. STUDY DESIGN: A database of women receiving outpatient preterm labor surveillance services was studied for the period 1988 to 2002. Included were women with twin gestations under 30 weeks' gestation at start of outpatient services. We compared pregnancy outcomes for twin gestations with hydramnios (n=201) to twin gestations that had normal amniotic fluid volume (n=13,111). RESULTS: Obstetrical and perinatal outcomes in twin pregnancies were adversely affected by the presence of hydramnios. Delivery was shifted to earlier gestations in women with hydramnios (32.8 vs 35.1 weeks, p<0.001), especially under 32 weeks (38.3 vs 12.7%). Perinatal loss was notable in women with hydramnios: stillbirths (12.7 vs 1.1%, p<0.001) and neonatal mortality (7.5 vs 1.1%, p<0.001). CONCLUSIONS: Hydramnios in twin gestations negatively impacts gestational age at delivery. The incidence of perinatal mortality is significantly increased in the presence of hydramnios.  相似文献   
970.
Aims: To assess the effect of loratadine in exercise induced asthma. Methods: Randomised, double blind, placebo controlled study of 10 mg oral loratadine, once daily for three days in 11 children. At the end of the treatment period FEV1 was measured, and patients were exercised on a treadmill. FEV1 measurements were repeated at intervals after exercise. Results: Loratadine significantly reduced the decrease in FEV1 after exercise at two, five, 10, 15, and 30 minutes, compared with placebo (p < 0.05). However, the mean decrease in FEV1 at five minutes was more than 15% of baseline in the loratadine group. Conclusions: Loratadine reduces, but does not prevent, exercise induced asthma in children.  相似文献   
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