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111.
Insular carcinoma of the thyroid   总被引:1,自引:0,他引:1  
Thyroid surgeons are becoming increasingly more aware of a histologically distinct subset of thyroid carcinoma whose classification falls between well-differentiated and anaplastic carcinomas with respect to both cell differentiation and clinical behavior. This subtype of tumors has been categorized as poorly differentiated or insular carcinoma, based on its characteristic cell groupings. Although the differentiation of insular carcinoma from other thyroid carcinomas has important prognostic and therapeutic significance, relatively little about insular carcinoma has been published in the otolaryngology literature. In this article, we describe a new case of insular carcinoma and we discuss the findings of our review of the literature. We conclude that insular thyroid carcinoma warrants aggressive management with total thyroidectomy followed by radioactive iodine ablation of any remaining thyroid tissue.  相似文献   
112.
113.
We describe two patients, who presented with erythematous facial plaques, in keeping with neutrophilic eccrine hidradenitis, during chemotherapy for acute myeloid leukaemia. Both patients were neutropaenic and febrile. Histology showed a dermal neutrophilic infiltrate around the eccrine glands with gland destruction. The importance of recognizing this disorder is to prevent the inappropriate use of antibiotics as it is self limiting.  相似文献   
114.
cbl-b inhibits epidermal growth factor receptor signaling   总被引:6,自引:0,他引:6  
The role of cbl-b in signaling by the epidermal growth factor receptor (EGFR) was studied and compared with c-cbl. We demonstrate in vivo, that cbl-b, like c-cbl, is phosphorylated and recruited to the EGFR upon EGF stimulation and both cbl proteins can bind to the Grb2 adaptor protein. To investigate the functional role of cbl proteins in EGFR signaling, we transfected cbl-b or c-cbl into 32D cells overexpressing the EGFR (32D/EGFR). This cell line is absolutely dependent on exogenous IL-3 or EGF for sustained growth. 32D/EGFR cells overexpressing cbl-b showed markedly inhibited growth in EGF compared to c-cbl transfectants and vector controls. This growth inhibition by cbl-b was the result of a dramatic increase in the number of cells undergoing apoptosis. Consistent with this finding, cbl-b overexpression markedly decreased the amplitude and duration of AKT activation upon EGF stimulation compared to either vector controls or c-cbl overexpressing cells. In addition, the duration of EGF mediated MAP kinase and Jun kinase activation in cells overexpressing cbl-b is shortened. These data demonstrate that cbl-b inhibits EGF-induced cell growth and that cbl-b and c-cbl have distinct roles in EGF mediated signaling.  相似文献   
115.
Flexible fiberoptic bronchoscopy with multiplanar fluoroscopic control is shown to be effective in the transbronchial drainage of pulmonary abscesses. A new technique which permits the intracavitary placement of brush forceps and fine arterial catheters is described. This has facilitated the rapid defervescence of fever and established immediate endobronchial drainage. Seventy percent of patients had complete radiographic closure of their abscess cavities at three months. Clinical findings are presented and the role of aspiration in pathogenesis of pulmonary abscess is stressed.  相似文献   
116.
The results of 49 serum gentamicin assays from children of 2 weeks to 11 years of age are presented. The dose of gentamicin given 8-hourly intramuscularly ranged from 0-7 mg/kg-4-9 mg/kg. Doses of 1-7 mg/kg or less did not give adequate serum concentrations. As a result of these observations it is suggested that an intramuscular dose of 2-5 mg/kg given 8-hourly is suitable for most children in the absence of renal failure, but that adjustment of the dose according to serum gentamicin concentration is necessary.  相似文献   
117.
Our objectives were to study the distribution of Chlamydia trachomatis and Mycoplasma genitalium in men with or without non-gonococcal urethritis (NGU) and their respective female partners. A case-control study was carried out to which men with or without NGU and their female partners were recruited. All study participants were tested for the presence of C. trachomatis and M. genitalium. An analysis firstly of the distribution of each of these microorganisms among men with or without urethritis and their respective female partners was carried out. Furthermore, we examined the association of each of these microorganisms and NGU when the other had been excluded. Chlamydia trachomatis was present in 14 (36%) of 39 men with NGU compared to none of 12 men without NGU (P=0.022). The prevalence rates for female partners of men with NGU were 10 (26%) of 39 compared to none of 12 partners of men without NGU (P=0.092). M. genitalium was detected in 12 (33%) of 36 men with NGU compared to 1 (9%) of men without NGU (not significant; P=0.147). The prevalence rates for female partners of men with NGU were 10 (32%) of 31 women compared to none of 7 partners of men without NGU (not significant; P=0.156). There was a greater concordance than discordance of carriage of each of the 2 microorganisms among the study couples and each tended to be carried independently of the other by men. Analysis of the association between the presence of C. trachomatis in men and NGU was significantly improved by the exclusion of men with M. genitalium (P=0.0058). Likewise, the association between the presence of M. genitalium in men and NGU was significantly improved by the exclusion of couples in whom either the man or woman was C. trachomatis-positive (P=0.049). The independent carriage of C. trachomatis and M. genitalium by men with NGU, coupled with the improved association between each pathogen and NGU by exclusion of the other provides support for the separate role of each in the aetiology of NGU.  相似文献   
118.
Lung transplantation is a therapeutic option for patients with end stage lung diseases, but long-term survival remains poor, primarily due to chronic allograft rejection. Bronchiolitis obliterans (BO), a fibrotic process resulting in progressive narrowing of bronchiolar lumens and airflow obstruction, is a manifestation of chronic allograft rejection. The term obliterative bronchiolitis ( OB) is synonymous. Once bronchiolitis obliterans syndrome (BOS) develops, progressive decline in pulmonary function is typical; most patients die of respiratory failure within 5 years of onset. The diagnosis of BOS is usually made by clinical, physiological, and radiographic parameters. The dominant risk factor for BOS is acute allograft rejection, but additional factors play contributory roles [e.g., infections; human leukocyte antigen (HLA) mismatching; and injury to the allograft or airways]. The pathogenesis of BOS is complex and involves myriad cell types (both immune and nonimmune) and release of diverse cytokines and chemokines. Unfortunately, current therapies for BOS are of unproven value. A greater understanding of the pathogenic mechanisms operative in BOS are critical to developing novel strategies to treat and prevent this devastating complication.  相似文献   
119.

Background and objectives

Masked hypertension and elevated nighttime BP are associated with increased risk of hypertensive target organ damage and adverse cardiovascular and renal outcomes in patients with normal kidney function. The significance of masked hypertension for these risks in patients with CKD is less well defined. The objective of this study was to evaluate the association between masked hypertension and kidney function and markers of cardiovascular target organ damage, and to determine whether this relationship was consistent among those with and without elevated nighttime BP.

Design, setting, participants, & measurements

This was a cross-sectional study. We performed 24-hour ambulatory BP in 1492 men and women with CKD enrolled in the Chronic Renal Insufficiency Cohort Study. We categorized participants into controlled BP, white-coat, masked, and sustained hypertension on the basis of clinic and 24-hour ambulatory BP. We obtained echocardiograms and measured pulse wave velocity in 1278 and 1394 participants, respectively.

Results

The percentages of participants with controlled BP, white-coat, masked, and sustained hypertension were 49.3%, 4.1%, 27.8%, and 18.8%, respectively. Compared with controlled BP, masked hypertension independently associated with low eGFR (−3.2 ml/min per 1.73 m2; 95% confidence interval, −5.5 to −0.9), higher proteinuria (+0.9 unit higher in log2 urine protein; 95% confidence interval, 0.7 to 1.1), and higher left ventricular mass index (+2.52 g/m2.7; 95% confidence interval, 0.9 to 4.1), and pulse wave velocity (+0.92 m/s; 95% confidence interval, 0.5 to 1.3). Participants with masked hypertension had lower eGFR only in the presence of elevated nighttime BP (−3.6 ml/min per 1.73 m2; 95% confidence interval, −6.1 to −1.1; versus −1.4 ml/min per 1.73 m2; 95% confidence interval, −6.9 to 4.0, among those with nighttime BP <120/70 mmHg; P value for interaction with nighttime systolic BP 0.002).

Conclusions

Masked hypertension is common in patients with CKD and associated with lower eGFR, proteinuria, and cardiovascular target organ damage. In patients with CKD, ambulatory BP characterizes the relationship between BP and target organ damage better than BP measured in the clinic alone.  相似文献   
120.
To evaluate the risks of and optimal method for valve dilation in aortic stenosis, balloons of different sizes were used to dilate the normal aortic root in 16 lambs and then stenotic valves in 15 children. In the lambs, inflated balloon to aortic anulus diameter ratios ranged from 0.9 to 1.5. These hearts were examined immediately after the procedure. Ratios of 0.9 to 1.1 did not produce significant damage to the left ventricular outflow tract, whereas those of 1.2 to 1.5 produced tears or hematomas, or both, of the aortic valve leaflets (n = 3), mitral valve leaflets (n = 4) and interventricular septum (n = 4). The 15 patients, aged 10 days to 15 years, underwent 16 balloon aortic valvotomy procedures. The balloon-aortic anulus ratio ranged from 0.67 to 1.1 (mean 0.90). The average pressure gradient decreased 69% and, overall, the peak systolic gradient decreased from 86 +/- 21 to 28 +/- 14 mm Hg (p less than 0.01) and the aortic valve area increased from 0.44 +/- 0.11 to 0.73 +/- 0.22 cm2/m2 (p less than 0.01). Immediately after the procedure an increase in aortic regurgitation was noted in 8 (57%) of 14 patients, but was never greater than 3+ and has been well tolerated. Other early complications encountered consisted of transient left bundle branch block in two patients, temporary femoral artery occlusion in three and femoral artery rupture requiring operative management in one infant. Balloon valvotomy can reduce the transvalvular gradient in most patients with valvular aortic stenosis when a balloon less than 1.1 times the aortic root diameter is used.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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