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31.
Chondrosarcomas are malignant tumours of cartilaginous origin. They range from a well-differentiated growth resembling a benign cartilage tumour to a high-grade malignancy with aggressive local behaviour and the potential to metastasize. Only 5% to 10% of chondrosarcomas are known to occur in the head and neck region. A case of chondrosarcoma of the anterior region of the mandible is presented, along with a review of the relevant literature.  相似文献   
32.
A three-year-old boy was investigated for inexplicable incessant crying. On examination, his left wrist was mildly swollen (three to four months) and sensitive. Exploration and carpal tunnel decompression of the left wrist with incisional biopsy was performed for the presence of a fusiform swelling intimately associated with the median nerve. Histopathology revealed the presence of enlarged nerve bundles admixed with mature fat cells and diffuse fibroblastic proliferation. Three months later, he underwent urgent contralateral carpal tunnel decompression for a similar presentation. The final diagnosis was bilateral fibrolipomatous hamartoma (FLH) of the median nerves causing acute bilateral compression neuropathy.FLH of the median nerve is an extremely unusual cause of acute bilateral carpal tunnel syndrome in a young child presenting with ‘incessant crying’. A comprehensive review of FLH including epidemiology, etiology, clinical presentation, differential diagnosis, imaging, pathology, treatment and prognosis is discussed.  相似文献   
33.
Chlorotoxin is a small 36 amino-acid peptide identified from the venom of the scorpion Leiurus quinquestriatus. Initially, chlorotoxin was used as a pharmacological tool to characterize chloride channels. While studying glioma-specific chloride currents, it was soon discovered that chlorotoxin possesses targeting properties towards cancer cells including glioma, melanoma, small cell lung carcinoma, neuroblastoma and medulloblastoma. The investigation of the mechanism of action of chlorotoxin has been challenging because its cell surface receptor target remains under questioning since two other receptors have been claimed besides chloride channels. Efforts on chlorotoxin-based applications focused on producing analogues helpful for glioma diagnosis, imaging and treatment. These efforts are welcome since gliomas are very aggressive brain cancers, close to impossible to cure with the current therapeutic arsenal. Among all the chlorotoxin-based strategies, the most promising one to enhance patient mean survival time appears to be the use of chlorotoxin as a targeting agent for the delivery of anti-tumor agents. Finally, the discovery of chlorotoxin has led to the screening of other scorpion venoms to identify chlorotoxin-like peptides. So far several new candidates have been identified. Only detailed research and clinical investigations will tell us if they share the same anti-tumor potential as chlorotoxin.  相似文献   
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ITGB6 is known to be one of the major receptor components involved in host tropism of foot-and-mouth disease (FMD) virus in cattle. A competitive PCR technique called ARMS PCR was adapted to identify a single-nucleotide polymorphism (SNP), G29A, db SNP Id: rs109075046, in the 5′ untranslated region (5′UTR) of the bovine ITGB6 gene. Genotype profiling identified three kinds of genetic variation within the targeted SNP among Frieswal crossbred cattle. The occurrence of FMD in the three genotypes was further evaluated, revealing a clear role in the incidence of FMD in the studied population.  相似文献   
37.

Background

The emerging field, Lifestyle Medicine (LM), is the evidence-based practice of assisting individuals and families to adopt and sustain behaviors that can improve health. While competencies for LM education have been defined, and undergraduate curricula have been published, there are no published reports that address graduate level fellowship in LM. This paper describes the process of planning a LM fellowship curriculum at a major, academic teaching institution.

Methods

In September 2012 Harvard Medical School Department of Physical Medicine and Rehabilitation approved a “Research Fellowship in Lifestyle Medicine”. A Likert scale questionnaire was created and disseminated to forty LM stakeholders worldwide, which measured perceived relative importance of six domains and eight educational experiences to include in a one-year LM fellowship. Statistical procedures included analysis of variance and the Wilcoxon signed-rank test.

Results

Thirty-five stakeholders (87.5%) completed the survey. All domains except smoking cessation were graded at 4 or 5 by at least 85% of the respondents. After excluding smoking cessation, nutrition, physical activity, behavioral change techniques, stress resiliency, and personal health behaviors were rated as equally important components of a LM fellowship curriculum (average M?=?4.69, SD?=?0.15, p?=?0.12). All educational experiences, with the exception of completing certification programs, research experience and fund raising, were graded at 4 or 5 by at least 82% of the responders. The remaining educational experiences, i.e. clinical practice, teaching physicians and medical students, teaching other health care providers, developing lifestyle interventions and developing health promotion programs were ranked as equally important in a LM fellowship program (average M?=?4.23, SD?=?0.11, p?=?0.07).

Conclusions

Lifestyle fellowship curricula components were defined based on LM stakeholders’ input. These domains and educational experiences represent the range of competencies previously noted as important in the practice of LM. As the foundation of an inaugural physician fellowship, they inform the educational objectives and future evaluation of this fellowship.
  相似文献   
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Ursolic acid isolated from the leaves and stems of Duboisia myoporoides (Solanaceae) was bioassayed by leaf disc method for feeding deterrence using Spilosoma obliqua and Spodoptera litura as test insects. This compound was proved to be a potent antifeedant under laboratory conditions. Azadirachtin was used as standard. Ursolic acid produced 90.12% and 91.96% inhibition at 5000 ppm concentration, respectively, against S. obliqua and S. litura .  相似文献   
40.
Synthesis of dihydroisoquinolinone-4-methylboronic esters from N-allylcarboxamides and B2(Pin)2via domino Heck/borylation approach is reported. A quinoxaline-based NHC-palladacycle [Pd(C∧C:)PPh3Cl], which has been structurally characterized, is used as a catalyst. The scope of the substrate with a wide range of substituents is explored. In addition to the synthesis of title compounds, a few examples of methylboronic esters of indoline and benzofuran motifs have also been prepared using the same protocol.

Synthesis of dihydroisoquinolinone-4-methylboronic esters from N-allylcarboxamides and B2(Pin)2via domino Heck/borylation has been achieved by using a quinoxaline-based NHC-palladacycle [Pd(C∧C:)PPh3Cl].  相似文献   
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