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Persistent exposure to inorganic lead (Pb) is known to adversely affect the immune system. In the present study, we assessed the effect of chronic Pb exposure on susceptibility to infection by the facultative intracellular pathogen Salmonella enterica serovar Typhimurium. Mice were exposed to 10 mM Pb-acetate in drinking water for approximately 16 weeks, resulting in a significant level of Pb in the blood (106.2+/-8.9 microg/dl). Pb exposure rendered mice susceptible to Salmonella infection, manifested by increased bacterial burden in target organs and heightened mortality. Flow cytometric analysis of the splenic cellular composition in normal and Pb-exposed mice revealed no gross alteration in the ratios of B and T lymphocytes or myeloid cells. Similarly, the capacity of B and T cells to upregulate the expression of activation antigens in response to mitogenic or inflammatory stimuli was not hindered by Pb exposure. Analysis of the ability of ex vivo-cultured splenocytes to secrete cytokines demonstrated a marked reduction in IFN-gamma and IL-12p40 production associated with Pb exposure. In contrast, secretion of IL-4 by splenocytes of Pb-treated mice was 3- to 3.6-fold higher than in normal mice. The increased capacity to produce IL-4 correlated with a shift in the in vivo anti-Salmonella antibody response from the protective IgG2a isotype to the Th2-induced IgG1 isotype. We conclude that chronic exposure to high levels of Pb results in a state of immunodeficiency which is not due to an overt cytotoxic or immunosuppressive mechanism, but rather is largely caused by a shift in immune responsiveness to Th2-type reactions.  相似文献   
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IntroductionThe recent interest in sleep-related breathing disorders has re-opened the old debate as to whether there is a causal relationship between upper respiratory obstruction and abnormalities in dentofacial development.ObjectiveTo establish the impact of dentofacial development on sleep-related breathing disorders in children.MethodThis is a prospective study in which the dentofacial studies of 30 children, diagnosed with a sleep-related breathing disorder using polysomnography, were compared with a control group of 30 healthy children. The ages of both groups were between 3 and 13 years.ResultsThe statistical analysis showed significant differences between the groups in the proportion of children with a narrow palate (83% of the problem group and 57% in the control; P = 0.024) and cross bite (40% and 13%; P = 0.020). On comparing the angles measured, the only statistically-significant difference was the skull base-mandibular plane angle: The problem children group had a mean of 37.59 ± 5.56 and the control group, a mean of 34.41 ± 4.62 (P = 0.023).ConclusionChildren with sleep-related breathing disorders have abnormalities in facial and dental development caused by upper respiratory obstruction. These anomalies, vertical growth of the face, narrow palate and dental occlusion changes should be taken into account when assessing the indication for a adenotonsillectomy.  相似文献   
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Basaloid follicular hamartoma is not a well-recognized clinical entity and has often been diagnosed as trichoepithelioma or basal cell carcinoma. It is a unique benign follicular tumour which comprises a variety of clinical manifestations. We present the case of a 24-year-old male with unilateral basaloid follicular hamartoma present at birth and later misdiagnosed as basal cell carcinoma. Histological features of basaloid follicular hamartoma are not always diagnostic and clinico-pathological correlation is particularly important to distinguish this benign hamartoma from other basaloid tumours including basal cell carcinoma. Continuous follow-up of our patient did not reveal any clinical or histological malignant transformation.  相似文献   
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Background  

Intraoperative penile erections following the initiation of either regional or general anaesthesia is rare; however, when it occurs in patients undergoing urologic procedures it may delay, or even cancel the planned surgery. The aetiology is unclear. Various treatments proposed for producing detumescence are not always effective. Use of intracavernous alpha-adrenergic agonists is an efficient and rapid but short-lasting treatment. Furthermore, repeated intracavernous injections of vasoactive drugs may be harmful. Dexmedetomidine is a potent, selective α2-adrenoreceptor agonist. In our study, we evaluated the effect of dexmedetomidine on intraoperative penile erection.  相似文献   
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BACKGROUND/AIMS: Unroofing, cystopericystectomy, or cystic evaluation and omentoplasty have been used in videolaparoscopic treatment in hepatic hydatidosis since 1992. Currently it is shown that videolaparoscopic treatment has been carried out successfully in selected cases. METHODOLOGY: Fifteen hepatic hydatid cysts in 12 cases were treated by videolaparoscopic methods. Formerly in the 5 cases, the cysts were aspirated with a needle designed for a 5-mm trocar, leaving a cystic cavity that was tension-free, then scolicidal solution was injected and aspirated. In the last 7 patients an aspirator-grinder apparatus was used. Intraoperative ultrasonography was applied in all patients. RESULTS: All the cysts were treated by drainage and omentoplasty. In one case cystic cavity infection was diagnosed in the 2nd postoperative month (morbidity rate 8.33%). Another patient died due to cerebral hydatid cyst and multiple organ failure after the postoperative first month (mortality rate 8.33%). Operative mortality was not seen. CONCLUSIONS: Videolaparoscopic treatments of hepatic hydatid cysts may be carried out successfully in selected cases.  相似文献   
69.
OBJECTIVE: Bladder tumors are among the most common types of malignant neoplasms of the urinary tract. The purpose of this study was to evaluate the potential value of 3-dimensional (3D) sonography and sonographic cystoscopy in detection of bladder tumors. METHODS: Thirty-one patients with suspected or known bladder tumors were included this study. All patients underwent 3D sonography and conventional cystoscopy within 15 days. The number, size, location, and morphologic features of the lesions were evaluated on gray scale, 3D virtual, and multiplanar reconstruction images obtained from the patients. The results of 3D sonographic cystoscopy were compared with the findings from conventional cystoscopy, which was considered the reference standard. RESULTS: Twenty-eight (90.3%) of 31 3D virtual sonographic cystoscopic studies had good or excellent image quality. Conventional cystoscopy revealed 47 lesions in 22 of 28 patients; 3D sonographic virtual cystoscopy showed 41 (87.2%) of 47 lesions. Three-dimensional virtual sonography alone had sensitivity of 96.2%, specificity of 70.6%, a positive predictive value of 93.9%, and a negative predictive value of 80% for tumor detection. The combination of gray scale sonography, multiplanar reconstruction, and 3D virtual sonography had sensitivity of 96.4%, specificity of 88.8%, a positive predictive value of 97.6%, and a negative predictive value of 84.2% for tumor detection. CONCLUSIONS: Three-dimensional sonography is a promising alternative noninvasive technique for use in detection of bladder tumors, their localization, and perivesical spreading. The location, size, and morphologic features of the tumors shown on 3D sonography agreed well with the findings of conventional cystoscopy.  相似文献   
70.
Ventricular ectopic beats (VEBs) are often encountered in daily clinical practice. Clinical significance of VEBs seen in patients without structural cardiovascular diseases is controversial. We aimed to investigate the effects of VEBs on left atrium (LA) function using speckle tracking echocardiography with LA strain parameters. Patients with frequent VEBs (more than 30 times in 1 h, according to the Lown classification) were identified. Identified patients were evaluated by speckle tracking methods. There were 40 patients with frequent VEBs and 40 controls in our study. The general characteristics were similar of the study population. The LA global longitudinal strain parameters were significantly different. Global Peak atrial longitudinal strain (PALS) (38.39 ± 7.93 vs. 44.15 ± 6.71, p = 0.001) and peak atrial contraction strain (PACS) (16.37 ± 4.58 vs. 20.49 ± 3.65, p = 0.000) were revealed significantly lower in the VEBs group. Time to peak longitudinal strain (TPLS) was found significantly longer in the VEBs group [485.5 (352–641) vs. 435 (339–516.5) p = 0.000]. Number of VEBS was correlated with TPLS (r = 0.499, p = 0.000). PALS and PACS were negatively correlated with number of VEBs (r = ?0.348, p = 0.002 and r = ?0.444, p = 0.000, respectively). We described that in this study, The LA functions are affected by VEBs adversely. This deterioration is increasing as the number of VEBs.  相似文献   
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