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51.
Background: A clinicopathological analysis and long‐term follow up of 32 patients with Hurthle cell neoplasm (HCN) was undertaken to contrast the clinical and histological features between benign versus malignant HCN of thyroid and to examine the effect of treatment on the outcome. Methods: This is a retrospective study of 32 patients with HCN who were identified out of an archival clinical/pathological/imaging database of 3752 thyroid cancer patients seen between 1976 and June 2006. All patients underwent thyroid surgery. Data for the non‐surgical treatment along with follow up were also analysed. Results: Seventeen patients were classified as malignant HCN (MHCN) and 15 as benign HCN (BHCN). Among the MHCN, there were 11 women and 6 men, whereas among BHCN there were 14 women and 1 man. Three patients designated MHCN presented with metastases, one with pulmonary metastases and two others with skeletal metastases who developed lung metastases 9–19 months later. The mean tumour size was 4.43 ± 0.66 cm for MHCN, and 2.57 ± 0.32 cm for BHCN (P = 0.03). Multicentric tumour foci were evident in five cases (29%) of MHCN but none among the BHCN (P = 0.03). At neck exploration cervical lymph node dissection was carried out in nine MHCN patients with findings of tumour metastases in 33%. Postoperatively, three MHCN patients had no thyroid remnant on ultrasound and computed tomography of neck and undetectable serum thyroglobulin; these were considered to be in remission. Fourteen other MHCN patients with postoperative thyroid remnant and/or distant metastases received 131I treatment. Eight of these patients had negative whole‐body scans after 131I treatment and undetectable thyroglobulin. Accordingly, 11 MHCN patients (64.7%) showed evidence of remission and 6 patients did not respond to 131I treatment. After a mean follow up of 35 months, all BHCN patients are alive with no evidence of disease. Of the MHCN, 11 (64.7%) were in remission and 35% had evidence of persistence/recurrence. One patient who had recurrence is dead. A lack of effectiveness of 131I therapy in two patients with distant metastases is an important finding. Conclusion: Features of MHCN consisted of a large tumour size, unequivocal capsular and vascular invasion, multicentric tumour foci, metastatic lymph node deposits in one‐third of patients and presence of distant metastasis in a few. Findings of dominant Hurthle cell cytology in a fine‐needle aspiration biopsy from a thyroid nodule should prompt surgical resection of the lesion to assess malignancy.  相似文献   
52.
Parathyroid autotransplantation is a technique for ensuring the continued function of parathyroid tissue at the time of total thyroidectomy (TT). The aim of this study was to ascertain whether the number of parathyroids transplanted affects the incidence of temporary and permanent hypoparathyroidism. A retrospective cohort study included all patients undergoing a TT in a single unit between July 1998 and June 2003. The number of parathyroids transplanted, the final pathology, and the incidence of temporary and permanent hypoparathyroidism were documented. Fisher’s exact test was used for statistical analysis. A total of 1196 patients underwent a TT during the 5 years studied. Of these, 306 (25.6%) had no parathyroids transplanted, 650 (54.3%), 206 (17.2%), 34 (2.8%) had 1,2, or 3 glands autotransplanted, respectively. The incidence of temporary hypoparathyroidism was 9.8% for no gland transplants, 11.9%, 15.1%, and 31.4% for 1,2,and 3 gland transplants, respectively (p < 0.05). The incidence of permanent hypoparathyroidism was 0.98%, 0.77%, 0.97%, and 0%, respectively (p = NS). The incidence of temporary hypoparathyroidism was higher when surgery was performed for Graves’ disease. Temporary hypocalcemia is closely related to the number of autotransplanted parathyroids during TT. The long-term outcome is not affected by the number of parathyroids autotransplanted. A “ready selective” approach to parathyroid autotransplantation is an effective strategy for minimizing the rate of permanent hypoparathyroidism.  相似文献   
53.
Ovarian Hyperstimulation Syndrome (OHSS) is a known iatrogenic complication of ovulation induction. Our experience of such complication while managing basic assisted conception cycles has been analysed in the present study. 12 such cases were identified in 976 cycles studied giving an overall incidence of 1.22%. All the cases were of mild to moderate variety and were managed conservatively. The duration of the complication ranged between 10 days to 6 weeks. Polycystic ovarian disease, LH: FSH ratio of more than 1, presence of four or more secondary follicles were found to be important predictive criteria. Identification of predictive factors of OHSS can be helpful in taking due care while using ovulation inducing drugs. Conception does worsen OHSS, but termination is usually not necessary.Key Words: OHSS, Ovulation Induction  相似文献   
54.

Background

There is a great deal of disparity in the incidence of breast cancer in rural and urban India on one hand and between India and Western population on the other.

Methods

We analysed steroid receptor status in cases of breast cancer in a small sample of patients in armed forces. Infiltrating duct carcinomas of breast recorded histologically in mastectomy specimens in last two years were accessioned in the present study with reference to patient and tumour characteristics.

Result

In contrast to the higher rates reported in western literature, only 33 % of the tumours expressed estrogen receptors (ER) and progesterone receptors (PR), of which 24% were ER positive and 30% PR positive. Negative steroid receptor status did not correlate with presence or absence of metastatic nodes, however it was predominant amongst the high grade infiltrating duct carcinomas in this study. Necrosis and lymphovascular invasion demonstrated an inverse relationship with the ER/ PR reactivity. 70% of the node positive cases expressed Her –2/ Neu, reflecting a higher immunoreactivity in this subset of patients. Aneusomy for chromosomes 1, 11 and 17 was common in node positive cases.

Conclusion

Evaluation of chromosomal aberrations by Fluorescent In Situ Hybridization (FISH) technique correlates well with traditional histological parameters.Key Words: Breast carcinoma, Hormone receptors, Her –2/ Neu  相似文献   
55.
56.

Background

Electronic cigarette awareness and use has been increasing rapidly. E-cigarette brands have utilized social networking sites to promote their products, as the growth of the e-cigarette industry has paralleled that of Web 2.0. These online platforms are cost-effective and have unique technological features and user demographics that can be attractive for selective marketing. The popularity of multiple sites also poses a risk of exposure to social networks where e-cigarette brands might not have a presence.

Objective

To examine the marketing strategies of leading e-cigarette brands on multiple social networking sites, and to identify how affordances of the digital media are used to their advantage. Secondary analyses include determining if any brands are benefitting from site demographics, and exploring cross-site diffusion of marketing content through multi-site users.

Methods

We collected data from two e-cigarette brands from four social networking sites over approximately 2.5 years. Content analysis is used to search for themes, population targeting, marketing strategies, and cross-site spread of messages.

Results

Twitter appeared to be the most frequently used social networking site for interacting directly with product users. Facebook supported informational broadcasts, such as announcements regarding political legislation. E-cigarette brands also differed in their approaches to their users, from informal conversations to direct product marketing.

Conclusions

E-cigarette makers use different strategies to market their product and engage their users. There was no evidence of direct targeting of vulnerable populations, but the affordances of the different sites are exploited to best broadcast context-specific messages. We developed a viable method to study cross-site diffusion, although additional refinement is needed to account for how different types of digital media are used.  相似文献   
57.
Metabolic Brain Disease - Human diseases have always been a significant turf of concern since the origin of mankind. It is cardinal to know the cause, treatment, and cure for every disease...  相似文献   
58.
59.

Aim

To estimate global morbidity from acute bacterial meningitis in children.

Methods

We conducted a systematic review of the PubMed and Scopus databases to identify both community-based and hospital registry-based studies that could be useful in estimation of the global morbidity from bacterial meningitis in children. We were primarily interested in the availability and quality of the information on incidence rates and case-fatality rates. We assessed the impact of the year of study, study design, study setting, the duration of study, and sample size on reported incidence values, and also any association between incidence and case-fatality rate. We also categorized the studies by 6 World Health Organization regions and analyzed the plausibility of estimates derived from the current evidence using median and inter-quartile range of the available reports in each region.

Results

We found 71 studies that met the inclusion criteria. The only two significant associations between the reported incidence and studied covariates were the negative correlation between the incidence and sample size (P < 0.001) and positive correlation between incidence and case-fatality rate (P < 0.001). The median incidence per 100 000 child-years was highest in the African region – 143.6 (interquartile range [IQR] 115.6-174.6), followed by Western Pacific region with 42.9 (12.4-83.4), the Eastern Mediterranean region with 34.3 (9.9-42.0), South East Asia with 26.8 (21.0-60.3), Europe with 20.8 (16.2-29.7), and American region with 16.6 (10.3-33.7). The median case-fatality rate was also highest in the African region (31.3%). Globally, the median incidence for all 71 studies was 34.0 (16.0-88.0) per 100 000 child-years, with a median case-fatality rate of 14.4% (5.3%-26.2%).

Conclusions

Our study showed that there was now sufficient evidence to generate improved and internally consistent estimates of the global burden of acute bacterial meningitis in children. Although some of our region-specific estimates are very uncertain due to scarcity of data from the corresponding regions, the estimates of morbidity and case-fatality from childhood bacterial meningitis derived from this study are consistent with mortality estimates derived from multi-cause mortality studies. Both lines of evidence imply that bacterial meningitis is a cause of 2% of all child deaths.Meningitis is an infectious disease affecting the brain membrane and spinal cord (1). Globally, bacterial meningitis is the most severe type of meningitis, mainly caused by a triad of species Neisseria meningitidis, Streptocccus pneumonia, and Haemophilus influenzae (2). While viral meningitis is usually a self-limiting disease with good prognosis, bacterial meningitis is potentially fatal, requiring urgent medical assistance and management with antibiotics treatment (3). Various estimates of the burden of bacterial meningitis have been proposed to date, but they have mainly focused on mortality (4), long-term sequels (5), or etiology-specific morbidity and mortality (6-8).Interestingly, there have been no comprehensive attempts to estimate the overall global burden of bacterial meningitis in children. This is not surprising, because such attempt would face almost insurmountable methodological challenges. First, there is a problem with case definition of “bacterial meningitis” (9). In low resource settings, where the problem is most common, many children may present with “purulent meningitis,” whose cause is highly likely bacterial, but laboratory capacity may not be sufficient to isolate the causal agent and confirm the diagnosis. This leads to a discrepancy between morbidity burden estimates based on “all purulent meningitis” and “laboratory confirmed meningitis” – the latter always being lower than the former, but to a different extent in different contexts (10). The second large methodological obstacle is the problem of “meningitis belt.” The meningitis belt is the band of countries extending from Senegal to Ethiopia, characterized by semi-arid climate, dry seasons, and dusty winds, with seasonal outbreaks of meningococcal meningitis being recorded since the beginning of the 20th century (11). The problem with these epidemics is that they can last for several years and dramatically change the importance of meningococcus in comparison to the other two bacterial agents (S. pneumoniae and H. influenzae) both regionally and globally (11). This makes it difficult to express the “burden of disease” for any given year, because it will be very different in intra-epidemic and inter-epidemic years. Moreover, the extent of vaccine coverage against N. meningitidis, S. pneumoniae and H. influenzae is changing the burden rapidly and rather dramatically in many places, rendering the scarce evidence from before the period of vaccination rather useless and indicates a need of revision (12). Finally, the emergence of HIV/AIDS pandemic led to a substantial number of infected children, whose resistance to other infections is impaired and they present a specific category of population in which the rates of incidence and case-fatality rates may be very different from those in other children (13).It is apparent that meningitis continues to contribute significantly to global mortality and morbidity, but the impact of the efforts to control it is difficult to estimate given that we do not have comprehensive estimates of global morbidity patterns. Understanding the global morbidity from bacterial meningitis would be useful because it would also help to validate the existing mortality estimates through application of appropriate case-fatality rates. The purpose of the present study is to provide a comprehensive assessment of the evidence that is available for estimating the global morbidity from acute bacterial meningitis in children globally. We will also propose initial, robust estimates of the burden, with suggestions on the possible ways to address the methodological challenges in future studies.  相似文献   
60.
IntroductionFocal nodular hyperplasia, a benign liver tumour, is the second most common focal benign liver lesion, after a cavernous haemangioma. Contrast-enhanced ultrasound is used increasingly for the diagnostic work up and follow-up of focal liver lesions in adults, but is particularly valuable in the paediatric population, with the ability to reduce radiation and the nephrotoxic contrast agents used in computed tomography or magnetic resonance imaging. Confident recognition of focal nodular hyperplasia is important; it is benign, usually asymptomatic, of no clinical significance, of no clinical consequence or malignant potential. We present a case of focal nodular hyperplasia of the liver with its characteristic findings on conventional ultrasound, contrast-enhanced ultrasound with quantitative analysis and correlated with magnetic resonance imaging.Case presentation: A 15-year-old female with right upper quadrant abdominal pain was referred for liver ultrasound. A focal liver lesion was detected on B-mode ultrasound examination, and colour Doppler demonstrated no specific features. Contrast-enhanced ultrasound examination demonstrated early arterial enhancement, with a characteristic spoke-wheel pattern, centrifugal uniform filling of the lesion on the late arterial phase and sustained enhancement on the portal venous phase. Quantitative contrast-enhanced ultrasound has been performed, showing a typical curve of enhancement, as well as characteristic parametric images, supporting the interpretation of contrast-enhanced ultrasound and assisting the diagnosis. Magnetic resonance imaging demonstrated a central T2 hyperintense scar and similar enhancement characteristics as contrast-enhanced ultrasound on T1 gadolinium-enhanced sequences.ConclusionContrast-enhanced ultrasound is a useful technique for the differentiation of benign from malignant liver lesions and has the potential to establish the diagnosis of focal nodular hyperplasia, based on the enhancement pattern, which is similar to that observed on magnetic resonance imaging but can be better appreciated with superior temporal, contrast and spatial resolution of contrast-enhanced ultrasound.  相似文献   
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