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71.
72.
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   
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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   
75.

Objective:

Experimental pain models in human healthy volunteers are advantageous for early evaluation of analgesics. All efforts to develop nonsteroidal anti-inflammatory drugs (NSAIDs) which are devoid of gastrointestinal and cardiovascular system effects are still far from achieving a breakthrough. Hence we evaluated the analgesic activity of an ayurvedic drug, Boswellia serrata by using validated human pain models which has shown its analgesic activity both in-vitro and preclinical studies to evaluate the analgesic activity of single oral dose (125 mg, 2 capsules) of Boswellia serrata compared to placebo using mechanical pain model in healthy human subjects.

Materials and Methods:

After taking written informed consent, twelve healthy subjects were randomized (1:1) to receive single oral dose of Boswellia serrata (Shallaki®) 125 mg, 2 capsules or identical placebo in a crossover design. Mechanical pain was assessed using Ugo basile analgesymeter (by Randall Selitto test) at baseline and at 1 hr, 2 hrs and 3 hrs after test drug administration. Pain Threshold force and time and Pain Tolerance force and time were evaluated. Statistical analysis was done by paired t-test.

Results:

Twelve healthy volunteers have completed the study. Mean percentage change from baseline in Pain Threshold force and time with Boswellia serrata when compared to placebo had significantly increased [Force: 9.7 ± 11.0 vs 2.9 ± 3.4 (P = 0.05) and time: 9.7 ± 10.7 vs 2.8 ± 3.4 (P = 0.04)] at third hr. Mean Percentage change from baseline in Pain Tolerance force and time with Boswellia serrata when compared to placebo had significantly (P ≤ 0.01) increased at 1 hr, 2 hrs and 3 hrs.

Conclusion:

In the present study, Boswellia serrata significantly increased the Pain Threshold and Pain Tolerance force and time compared to placebo. Both study medications were well tolerated. Further multiple dose studies may be needed to establish the analgesic efficacy of the drug.KEY WORDS: Boswellia serrata, human pain models, randall selitto test, ugo basile analgesymeter  相似文献   
76.
ABSTRACT. Background: This study sought to determine the relationship between the frequency of current marijuana and alcohol use and cigarette quit attempts in male and female adolescent smokers. Methods: Data from a cross-sectional survey of health behaviors in high-school-aged adolescents were analyzed. Current cigarette smokers (n = 804) who reported use of at least 1 cigarette in the past month were divided into those with and without a history of at least 1 quit attempt (a self-reported episode of trying to “stop smoking”). Logistic regression models were fit to describe the association between the frequency of marijuana/alcohol use and a history of cigarette quit attempts. Results: Among the total sample, higher-frequency marijuana use (more than 6 times in the past 30 days) and frequent binge drinking (more than 5 days of binge drinking in the past 30 days) decreased the odds of having a past cigarette quit attempt (higher-frequency marijuana: adjusted odds ratio [AOR] = 0.56, 95% confidence interval [CI] = 0.36–0.86; frequent binge drinking: AOR = 0.49, 95% CI = 0.29–0.83). A significant gender interaction was observed for the relationship between higher-frequency marijuana use and a history of cigarette quit attempts (P = .03), with decreased odds in boys (AOR = 0.41, 95% CI = 0.22–0.77) but not in girls (AOR = 0.71, 95% CI = 0.37–1.33). Conclusions: Adolescent smokers who report higher-frequency marijuana use or frequent binge drinking have a decreased likelihood of a history of a cigarette quit attempt. The gender-related association between higher-frequency marijuana use and a history of quit attempts suggests that boys with greater substance use may need particularly intensive support to initiate quit attempts.  相似文献   
77.
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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79.
W J Deery  C S Rani 《Endocrinology》1991,128(6):2967-2975
The mechanism and site(s) of the defect responsible for desensitization to hormone stimulation of adenylyl cyclase (AC) vary with cell type. Plasma membrane preparations were assayed after treatment of primary cultured dog thyroid cells to determine the role of the TSH receptor, stimulatory and inhibitory guanine nucleotide binding proteins (Gs and Gi), and catalytic unit in AC desensitization. Exposure of cells to TSH or the phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), caused time dependent decreases in TSH-stimulated AC and [125I]TSH binding with approximately 50% decreases seen after 18 h; Bt2cAMP was unable to reproduce the TSH effect. Whereas TSH treatment caused concomitant decreases (approximately 25%) in both cyclase activity and [125I]TSH binding after 2 h, TPA treatment decreased AC activity after 6 h and binding only after 18 h. The protein kinase C inhibitor, H-7, prevented TPA-induced but not TSH-induced effects on AC and hormone binding. Membrane AC activation by cholera toxin or forskolin was not altered by 18 h pretreatment of cells with TSH or TPA, indicating that these agents had no apparent effect on intrinsic functionality of either Gs or the catalytic unit. TSH or TPA pretreatment of cells reduced subsequent toxin-mediated AD[32P]-ribosylation of Gs and Gi in isolated membranes. However, the TSH- and TPA-induced decreases in AD[32P]-ribosylation and desensitization do not appear to be due to endogenous ribosylation of G proteins, since treatment of cells with pertussis toxin, for example, to endogenously ribosylate Gi, both increased TSH-stimulated AC activity and failed to affect the ability of TSH or TPA to desensitize. Thus, in this system, although specific hormone-induced AC desensitization and receptor down-regulation conform to several aspects of classic homologous processes, similar effects are also induced by a nonreceptor (phorbol ester) pathway; desensitization, however, can precede down-regulation, possibly due to receptor-Gs uncoupling.  相似文献   
80.
We are in a new era of partner-based implementation research, and we need clear strategies for how to navigate this new era. Drawing on principles from community-based participatory research, the Clinical Public Health group of the Department of Veterans Affairs and the HIV/Hepatitis Quality Enhancement Research Initiative (HHQUERI) forged a longstanding partnership that has improved the care of Veterans with Human Immunodeficiency Virus (HIV) and Hepatitis C Virus. An exemplar HIV testing project epitomizes this partnership and is discussed in terms of the lessons learned as a result of our high level of collaboration around design, analysis, implementation, and dissemination across projects over the past several years. Lessons learned through this partnered testing program involve respecting different time horizons among the partners, identifying relevant research questions for both parties, designing flexible studies, engaging all partners throughout the research, and placing an emphasis on relationship building at all times. These lessons and strategies can benefit others conducting partner-based research both within the Veterans Health Administration (VA) and in other integrated healthcare systems.  相似文献   
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