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11.
BACKGROUND: Nitric oxide (NO) has contradictory roles in the pathophysiology of allergic inflammation in both allergic rhinitis (AR) and asthma. Small amounts of NO produced by constitutive NO synthase (NOS) is anti-inflammatory, whereas large amounts produced by inducible NOS (iNOS) are proinflammatory. OBJECTIVE: To investigate the difference in constitutive endothelial NOS (eNOS) and iNOS expression in nonallergic and allergic mucosa and the possible relation of this to the coexistence of asthma in seasonal AR. METHODS: Seventeen patients (10 women and 7 men) with seasonal AR and 9 nonallergic patients (5 women and 4 men) with nasal septum deviation were enrolled. Inferior turbinate nasal biopsy specimens were obtained in all. Levels of eNOS and iNOS expressed as immunohistochemical scores (HSCOREs) were determined immunohistochemically from the specimens. RESULTS: The mean +/- SD HSCOREs for eNOS in patients with seasonal AR were not significantly different from those of the nonallergic controls (1.85 +/- 0.78 vs 1.63 +/- 0.54; P = .12). On the other hand, the mean +/- SD HSCOREs for iNOS were significantly higher in patients with seasonal AR (1.75 +/- 0.75 vs 0.71 +/- 0.6; P = .004). Furthermore, although eNOS expression was not different between seasonal AR patients with and without asthma, the mean +/- SD HSCOREs for iNOS were significantly higher in the patients with asthma (1.93 +/- 0.78 vs 1.65 +/- 0.55; P = .01). CONCLUSION: Increased expression of iNOS might have a role in the development of allergic inflammation in upper and lower airways and in comorbidity of AR and asthma.  相似文献   
12.
Penicillin-resistant Streptococcus pneumoniae isolates (n = 76) from clinical samples of patients admitted to Hacettepe University Hospital between January 1997 and December 2001 were included in the study. MICs of penicillin G, erythromycin A, clindamycin, cefaclor, cefotaxime, vancomycin, chloramphenicol, tetracycline, ciprofloxacin and rifampicin were determined by agar dilution. The isolates were serogrouped on the basis of the Neufeld Quellung reaction and were typed by BOX-PCR. Genetic polymorphism of the penicillin resistance genes pbp2b and pbp2x was investigated by restriction fragment length polymorphism (RFLP) analysis. Of the 76 isolates tested, 64 (84.2%) showed intermediate resistance to penicillin, while 12 (15.8%) were resistant to higher levels of penicillin (MIC > or = 2 mg/L). The resistance patterns of the isolates revealed six different resistance profiles. There were 22 different serotypes, with c. 55% of the isolates belonging to serotypes 23B, 19A, 19F, 14, 6 A and 9V. Five distinct patterns for pbp2b and 12 distinct patterns for pbp2x were obtained by RFLP analysis of penicillin-binding protein genes. The combination of these patterns allowed isolates to be classified into 22 fingerprint subgroups. BOX-PCR analysis showed that the isolates fell into 14 distinct BOX genotypes, with 33 subtypes. Serotype 9V isolates with pbp genotype 2-6 and BOX-PCR type 4, 4.1 or 4.2 were related to the pandemic clone Spain(9V)-3. No relatedness to other international clones was detected among the other study strains, but genetic relatedness was observed among some of the serotype 19A and 23B isolates. Overall, the results demonstrated that most of the penicillin-resistant pneumococcal isolates in Turkey, other than those belonging to serotypes 9V, 19A and 23B, were derived from several independent clones, possibly resulting from multiple importation of strains originating from outside the country. Differences in pbp patterns, serotypes and resistance profiles among isolates that showed similar BOX-PCR patterns supported the hypothesis that horizontal transfer of capsular genes, pbp genes and other genetic determinants between S. pneumoniae and viridans group streptococci may have occurred.  相似文献   
13.
Secondary hyperparathyroidism is one of the most common complications of chronic kidney failure. If prolonged, parathyroid hormone release gains autonomy and tertiary hyperparathyroidism with parathyroid adenoma or hyperplasia can be develop. Tertiary hyperparathyroidism is associated with increased risk of mortality and morbidity; thus, treatment is recommended. Medical treatment includes phosphate binders, vitamin D analogues, and calcimimetic agents. Most cases of tertiary hyperparathyroidism can be controlled with medical treatment. When medical treatment options prove insufficient, parathyroidectomy is recommended. However, recurrence after parathyroidectomy is possible, which requires an alternative treatment. We present our percutaneous embolization experience, which has not been tried in the treatment of tertiary hyperparathyroidism in renal transplantation patients diagnosed with tertiary hyperparathyroidism.  相似文献   
14.
ObjectivesTo assess potential nosocomial coronavirus disease-2019 (COVID-19) transmission in patients who underwent robot-assisted laparoscopic procedures during the pandemic.Material and methodsProspective study in patients undergoing robot-assisted laparoscopy in urology or gynaecology within 2 academic hospitals. Patients underwent local preoperative COVID-19 screening using a symptoms questionnaire. Patients with suspicious screening underwent coronavirus real time-polymerase chain reaction (RT-PCR) and were excluded from robotic surgery if positive. Patients with symptoms postsurgery were systematically tested for coronavirus by RT-PCR. One-month postsurgery, all patients had a telephone consultation to evaluate COVID-19 symptoms.ResultsSixty-eight patients underwent robotic surgery during the study period (median age: 63-years [IQR: 53–70], 1.8 male: female ratio). Oncology was the main indication for robotic surgery (n = 62, 91.2%) and 26 patients (38.2%) received a chest CT-scan prior to surgery. Eleven patients (16.2%) were symptomatic after surgery of whom only 1 tested positive for coronavirus by RT-PCR (1.5%) and was transferred to COVID-19 unit with no life-threatening condition. No attending surgeon was diagnosed with COVID-19 during the study.ConclusionsRobot-assisted laparoscopic surgery seemed safe in the era of COVID-19 as long as all recommended precautions are followed. The rate of nosocomial COVID-19 transmission was extremely low despite the fact that we only used RT-PCR testing in symptomatic patients during the preoperative work-up. Larger cohort is needed to validate these results.  相似文献   
15.
16.
Twenty-seven children with mumps or chickenpox were taken as a model to evaluate the haematological consequences of viral infections including serum iron status. Blood samples were obtained from all patients at presentation and on the 21 st day of the disease. While haemoglobin, haematocrit, and meam corpuscular volume levels were similar in two measurements (P>0.05), the mean leucocyte, absolute lymphocyte and thrombocyte counts, mean serum iron, serum iron binding capacity and transferrin saturation levels were lower at presentation than on the 21 st day of the disease. The serum iron levels were below 30 g/dl in 16 (59.2%) patients at presentation while only 4 (14.8%) had low values on 21 st day. Twenty-four (88.9%) patients had an increment in the serum iron binding capacity levels and 2 (7.6%) reached values above the normal range on the 21 st day. Int 21 (77.8%) patients, the transferrin saturation levels were below the expected ranges at presentation but 26 (96.3%) showed an increment on the 21 st day. However, the mean ferritin level was higher at presentation. Therefore, during the evaluation of patients for anaemia, the presence of a recent acute viral infection should be documented so as to avoid unnecessary iron medication.  相似文献   
17.
OBJECTIVE: In an attempt to differentiate obstructive from non-obstructive dilation of the renal collecting system in children, a prospective clinical study was carried out. MATERIAL AND METHODS: During duplex Doppler sonography examination in 23 children resistive index (RI) and pulsatility index (PI) and RI ratio values before and after intraverous furasemide administration were compared with the findings obtained with diuretic renogram examination (t(1/2)). RESULTS: Evaluation of the results demonstrated that diuresis RI and PI determination may aid differentiation of severely obstructed renal units from those with slight (equivocal) or no obstruction. CONCLUSION: Kidneys with severe UPJ obstruction tended to have more elevated RI and PI values than the non-obstructed or equivocally obstructed ones. Again, determination of RIR values for each kidney showed the same elevation in severely obstructed kidneys, while non-obstructive or indeterminately obstructed ones demonstrated statistically insignificant changes.  相似文献   
18.
Microbial keratitis following penetrating keratoplasty.   总被引:2,自引:0,他引:2  
PURPOSE: To investigate the prevalence of microbial keratitis, predisposing risk factors and treatment modalities in patients who developed keratitis following penetrating keratoplasty (PK). PATIENTS AND METHODS: The records of 285 patients who had undergone PK between January 1991 and December 1995 in a tertiary care center were reviewed. Patients who developed postoperative microbial keratitis were evaluated for predisposing risk factors, microbiological etiology, response to broad spectrum antibiotic therapy and subsequent PK. Patients were mainly treated with fortified topical antibiotics with or without repeat PK. RESULTS: Of the 285 patient records reviewed, microbial keratitis developed in 21 eyes of 21 patients (7.4%). Seventy-one percent of infections occurred within 6 months after grafting. Keratitis initially began from the donor-recipient border in 16 cases (76.2%) and were central or paracentral in 5 patients. Predisposing risk factors included loose or exposed suture (9), suture removal (1), persistent epithelial defect (3), graft failure (3), contact lens wear (1), Stevens-Johnson syndrome (1). Fifteen (71.4%) patients were culture-positive consisting of Streptococcus pneumoniae (7), Staphylococcus aureus (5), Pseudomonas aureginosa (2), and Hemophilus influenzae (1). Forty-three percent of patients were successfully treated with medical therapy only. Seven patients underwent second PK for visual rehabilitation and 4 for tectonic purposes. After medical and surgical therapy, graft clarity was achieved in 17 (81%) of patients. CONCLUSIONS: The microbial keratitis following PK is a major postoperative problem affecting the long term prognosis. Careful selection of patients, and preoperative and postoperative control of risk factors, may decrease the frequency of this complication. Several factors, including loose or exposed sutures, epithelial defects, ocular surface disorders, and graft failure, may predispose patients to develop microbial keratitis following PK.  相似文献   
19.
BACKGROUND: On February 19, 2003, four patients (patients 1-4) in the neurology ward underwent cranial magnetic resonance angiography (MRA) and developed fever within 1 hour afterward. Klebsiella oxytoca was isolated from blood cultures of patients 1 through 3. OBJECTIVE: To identify the source of this cluster of nosocomial K. oxytoca bloodstream infections. DESIGN: Outbreak investigation. SETTING: A 1,000-bed university hospital. METHODS: The infection control team reviewed patient charts and interviewed nursing staff about the preparation and administration of parenteral fluids. The procedure of cranial MRA was observed. Arbitrarily primed polymerase chain reaction (AP-PCR) was performed to show the clonal relationship among these three strains. RESULTS: AP-PCR revealed that three K. oxytoca isolates had the same molecular profile. Cranial MRA was found to be the only common source among these patients. During MRA, before injection of the contrast medium, normal saline solution was infused to check the functioning of the intravenous catheter. Use of the solution for multiple patients was routine, but the access diaphragm of the bottle was not cleansed. The bottle of normal saline solution used on February 19 had already been discarded and the culture sample taken from the solution on the day of observation was sterile. CONCLUSIONS: We speculate that normal saline solution became contaminated during manipulation and that successive uses might have been responsible for this cluster. Poor aseptic techniques employed during successive uses appear to be the most likely route of contamination. Use of parenteral solutions for multiple patients was discontinued.  相似文献   
20.
Neonatal deaths in infants born at term are relatively rare in the USA, occurring in 0.9/1000 live births. Congenital malformations, perinatal asphyxia, infections and inborn errors of metabolism are the leading causes. Chromosomal malformation syndromes, congenital heart disease, pulmonary hypoplasia and severe neural tube defects comprise the majority of lethal malformations. Several skeletal dysplasias are lethal in the newborn infant. Group B Streptococcus still plays a major role in neonatal mortality while deaths due to other infectious agents have decreased. Hypoxic ischaemic encephalopathy is a significant cause of neonatal death. Inborn errors of metabolism have variable presentations but some, such as the fatty acid oxidation disorders, may present in neonates and cause sudden death.  相似文献   
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