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301.
Direct functionalization of C–H bonds has attracted great attention in recent years from the perspectives of atom and step economy. In this context, a variety of processes have been developed for the construction of synthetically and biologically important organic azides through the oxidative C–H bonds azidation. In this review, we have summarized recent progress in the direct azidation of C(sp2)–H bonds. The review is divided into three major sections: (i) direct azidation of aromatic C–H bonds; (ii) direct azidation of olefinic C–H bonds; and (iii) direct azidation of aldehydic C–H bonds. Mechanistic aspects of the reactions are considered and discussed in detail.

Direct functionalization of C–H bonds has attracted great attention in recent years from the perspectives of atom and step economy.  相似文献   
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Methylprednisolone pulse therapy has significant anti‐inflammatory effects in multiple sclerosis. Acute respiratory distress syndrome as a probable adverse effect of methylprednisolone pulse therapy in MS patients should be considered.  相似文献   
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Objective

To evaluate the value of conventional abdominal ultrasound and color Doppler in the diagnosis of inflammatory bowel disease (IBD) and its complications.

Materials and methods

40 patients suffering from colonic symptoms were evaluated by high resolution ultrasonography and color Doppler scanning.

Results

The accuracy of conventional abdominal ultrasound in detecting inflammatory bowel cases was 80% and the accuracy of color Doppler in detecting the hypervascularity was 75%.

Conclusion

Conventional ultrasound is a widely available non-invasive method for imaging the alimentary gastrointestinal tract. This can provide an important contribution for diagnosis and monitoring of disease activity. Color Doppler sonography has proved to be a valuable method for the assessment of disease activity in inflammatory bowel disease.  相似文献   
305.
Osteosarcoma is the most common primary bone malignancy, with a high propensity for local invasion, early metastasis and relapse. While the molecular mechanisms behind osteosarcoma development and metastasis have not yet been fully elucidated, research has highlighted an important role for Wnt signaling. Several Wnt ligands, receptors and coreceptors are highly expressed in osteosarcoma cell lines, while Wnt inhibitors are downregulated. As a result, research has begun to identify mechanisms with which to inhibit Wnt signaling. The use of Wnt pathway inhibitors and the targeting of c-Met, a Wnt regulated proto-oncogene, may be two possible mechanisms for treatment of osteosarcoma. In addition, as the Wnt signaling pathway is a regulator of stem cells, reagents that function as Wnt inhibitors are currently under investigation as inhibitors of cancer stem cell proliferation. Research involving the Wnt signaling pathway and cancer stem cells holds promise for novel treatment options in the future.  相似文献   
306.
Fatiguing exercise has been associated with a decrease in certain functions of neutrophils, whereas moderate exercise has generally been associated with an increase. Consumption of oat beta-glucan (ObetaG), a soluble fiber and mild immune system enhancer, may offset the immunosuppression associated with intense training and perhaps further enhance the benefits of moderate exercise. PURPOSE: To test the effects of ObetaG consumption on neutrophil function and number after both moderate and fatiguing exercise. METHODS: Male mice were assigned to one of six treatment groups. Fatiguing exercise mice (Ftg-ObetaG and Ftg-H2O) ran to volitional fatigue on a treadmill for three consecutive days, and moderate exercise mice (Mod-ObetaG and Mod-H2O) ran for six consecutive days for 1 h. Control mice (Con-ObetaG and Con-H2O) were exposed to the treadmill environment but did not run. ObetaG was consumed in the drinking water (approximately 0.6 mL x d(-1)) for 10 consecutive days. After rest or exercise on the last day of training, mice were given a 1-mL i.p. injection of thioglycollate. Mice were sacrificed 3 h later; neutrophils were harvested from the peritoneal cavity and counted, and their respiratory burst activity was measured using flow cytometry. RESULTS: Both moderate exercise and ObetaG increased neutrophil burst activity, whereas fatiguing exercise had no effect. Neutrophil number was increased by fatiguing exercise and ObetaG, but not moderate exercise. There were no additive effects of exercise and ObetaG on either of these variables. CONCLUSION: These data suggest that although not additive in their effects, both ObetaG and exercise can alter overall neutrophil respiratory burst activity (number and/or function), but only ObetaG increased both number and function, which may have important ramifications for defense against infection.  相似文献   
307.

Introduction

Following the Mongolian invasion of the Middle East in the thirteenth century, a regional power called the Ilkhanid emerged and was ruled by the heirs of Temujin from Mongolia. Embracing present-day Iran, Iraq, Afghanistan, Azerbaijan, areas of Russia, Turkey, and Pakistan, and nearby Middle Eastern territories, the Ilkhanid state patronized medicine and various other professions. Centered in Tabriz (Tauris), a city in the northwest of present-day Iran, was a non-profit-making educational and medical complex founded by Grand Minister Rashid al-Din Fazlollah Hamadani.

Methods

This paper reviews the literature regarding the rise and fall of the thirteenth century university and the Rabi Rashidi, emphasizing the structure of its medical school.

Conclusions

The background training of Rashid al-Din and his keen interest in science turned this complex, Rabi Rashidi (literally meaning the Rashidi Quarters), into a cosmopolitan university that freely trained medical scholars nationally and internationally. The possibility that Rashid al-Din was inspired by university developments in Europe is discussed.  相似文献   
308.
The objective of the present study was to assess smile aesthetics after orthodontic treatment in subjects with and without the extraction of four first premolars. Post-treatment coloured frontal photographs (4 × 6 inches) of 60 Pakistani subjects, 21 males and 39 females, aged between 15 and 30 years were assessed by one examiner. For 50 per cent (n = 30) of the patients, treatment included the extraction of four first premolars, whereas the other half were treated without extractions. Smile aesthetics were evaluated by a panel of 10 laypersons, five males and five females, aged between 20 and 30 years. Smile aesthetic parameters were measured using seven variables, and the ratios were calculated. An independent sample t-test was used to assess smile aesthetics. All seven variables namely smile width, smile height, visible dentition width, maxillary intercanine width, visible maxillary first molars, visible mandibular teeth, visible maxillary gingival margin, and the ratios between the above mentioned variables showed no detrimental effects following extraction of four first premolars on smile aesthetics.  相似文献   
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