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61.
Neurohydatidosis     
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature.  相似文献   
62.

Background  

From 1968 to 2002, Singapore experienced an almost four-fold increase in prostate cancer incidence. This paper examines the incidence, mortality and survival patterns for prostate cancer among all residents in Singapore from 1968 to 2002.  相似文献   
63.
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction.  相似文献   
64.
Fong  LY; Lau  KM; Huebner  K; Magee  PN 《Carcinogenesis》1997,18(8):1477-1484
Dietary zinc deficiency in rats induces hyperplasia in the esophagus and increases N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor incidence. Previous work showed a direct relationship between epithelial cell proliferation and esophageal tumor incidence in rats given multiple doses of NMBA. We investigated the effects of single low doses of NMBA in zinc-deficient rats since a single dose of 5.0 mg/kg was reported to be non-carcinogenic in rats. Zinc-sufficient and deficient rats received a single i.g. dose of NMBA at 0.5 or 2.0 mg/kg. At week 14, tumor incidence was 50% with 0.8 +/- 1.0 tumors/rat, and 80% with 2.2 +/- 1.9 tumors/rat, in deficient groups, D(0.5) and D(2.0), that received the lower and higher dose, respectively. In addition, two small papillomas were found in one out of eight untreated zinc-deficient rats. None of the NMBA-treated or untreated zinc- sufficient rats had any tumors. Esophageal cell proliferation, as determined by proliferating cell nuclear antigen (PCNA) immunohistochemistry, showed that, irrespective of NMBA treatment, deficient esophagi had significant increases in the number of labeled cells, the total number of cells, and the labeling index, as compared with zinc-sufficient ones. Mutations in Ha-ras and p53 genes in esophageal tumors were detected by single strand conformation polymorphism (SSCP) analysis. DNA sequencing of variant conformers revealed a point mutation (GGA-->GAA, codon 12) in Ha-ras in 4/5 (80%) and 5/8 (63%) tumors, from D(0.5) and D(2.0) rats, respectively. Three out of eight tumors from D(2.0) rats exhibited SSCP mobility shifts within p53 exons 5 and 7: two tumors (2/8, 25%) had missense mutations and the third, a silent mutation. Of the two tumors with p53 mutations, one had a double mutation (transition at codon 164, TCA-->TTA; transversion at codon 241, AGT-->TGT), and the other tumor, a transition at codon 172 (AGA-->GGA), with amino acid changes in all cases. In parallel with PCNA expression, elevated p53 expression was associated with hyperplastic and dysplastic regions, as well as with tumors, in deficient esophagi. In short, these data indicate that dietary zinc deficiency, with its associated sustained increased cell proliferation in the esophagus, can drive an otherwise non-tumorigenic dose of NMBA into a highly tumorigenic one.   相似文献   
65.
Southeast Asian immigrants have lower levels of Pap testing than any other racial/ethnic group in the US, and are particularly unfamiliar with western culture and biomedical concepts of prevention. We completed an ethnographic study (N = 42) focusing on cervical cancer screening among Cambodian American women. We also conducted a community-based survey (N = 413) to examine the generalizability of our qualitative results. This report summarizes the results, and describes how we used our findings to influence the content of a multifaceted intervention program targeting Cambodian immigrants. The following constructs were found to be barriers to cervical cancer control: a traditional orientation to the prevention, causation, and treatment of disease; lack of familiarity with western early detection concepts; low levels of knowledge about cervical cancer; concerns about the Pap testing procedure; and health care access issues. In general, the quantitative results confirmed our ethnographic findings. The intervention program, which is delivered by bicultural outreach workers, includes home visits, presentations at small group meetings, barrier-specific counseling, use of a Khmer-language video, and tailored logistic assistance (e.g., transportation and medical interpretation). Both the video and presentation provide cultural context while simultaneously addressing multiple barriers to screening (e.g., women's fear of surgery and preference for female providers). Outreach workers are trained to counsel women about 10 potential barriers including avoidance of biomedicine, perceptions that gynecologic exams are embarrassing, and lack of English proficiency. Our results reinforce the importance of considering health problems within the context of a population's traditional belief systems and daily routines.  相似文献   
66.
Following injection of horseradish peroxidase (HRP) solution in the gastrocnemius muscle or the extensor digitorum longus muscle in neonatal and developing albino rats, some neurones in the cervical enlargement, mid-thoracic region and sacral region were labelled in addition to the region of the spinal cord from where the sciatic nerves emerged. The labelling was most probably the result of diffusion of HRP solution from the site of injection to nearby structures.  相似文献   
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Intensity-modulated radiation therapy (IMRT) is a novel form of radiotherapy, which has the potential to reduce the amount of radiation unintentionally delivered to normal tissues while maintaining a high radiation dose to the tumor in comparison with standard radiation techniques. In adults, this technology has been implemented in a number of tumor sites, but in children it has been little used. This article will review the current studies in which IMRT has been used in children. It will also discuss possible future applications for IMRT, and anticipated problems with its use.  相似文献   
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