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Colorectal cancer is one of the most common malignancies in developed countries. Although guaiac-based fecal occult blood
tests have proven their efficacy for screening, they have major drawbacks. Immunochemical fecal occult blood tests are theoretically
superior as they can detect very small amounts of hemoglobin, and they are specific to human hemoglobin. Recently many different
immunochemical tests have been marketed, with variations in hemoglobin detection limit, mechanism of action, sample collection
method, and test development. Molecular tests represent an alternative to fecal blood tests, which have been designed to detect
certain fecal DNA mutations, or aberrant gene methylation (either hyper-or hypomethylation). In this review, we discuss a
selection of the most significant studies published in the last 3 years regarding noninvasive tools for colorectal cancer
screening. 相似文献
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Background. Polymers of lactic acid have been widely used for many years in different types of medical devices, such as resorbable sutures, intrabone implants, and soft tissue implants. Injectable poly-l-lactic acid (PLLA; Sculptra), a synthetic, biodegradable polymer, has gained widespread popularity in Europe for the treatment of facial changes associated with aging.
Objective. To provide background information on injectable PLLA and to describe clinical experience with its use in Europe for facial volume enhancement.
Methods. Technique varies with site of injection. Generally, the product is implanted subcutaneously or intradermally in a series of treatments. No allergy testing is required.
Results. Based on experience in more than 2,500 patients, injectable PLLA has been used successfully for the correction of nasolabial folds, mid- and lower facial volume loss, jawline laxity, and other signs of facial aging. Correction lasts for 18 to 24 months in most patients.
Conclusions. Injectable PLLA treatment provides an excellent and prolonged correction of a variety of facial wrinkles, depressions, and laxity with a minimally invasive procedure that does not require allergy testing or a recovery period. 相似文献
Objective. To provide background information on injectable PLLA and to describe clinical experience with its use in Europe for facial volume enhancement.
Methods. Technique varies with site of injection. Generally, the product is implanted subcutaneously or intradermally in a series of treatments. No allergy testing is required.
Results. Based on experience in more than 2,500 patients, injectable PLLA has been used successfully for the correction of nasolabial folds, mid- and lower facial volume loss, jawline laxity, and other signs of facial aging. Correction lasts for 18 to 24 months in most patients.
Conclusions. Injectable PLLA treatment provides an excellent and prolonged correction of a variety of facial wrinkles, depressions, and laxity with a minimally invasive procedure that does not require allergy testing or a recovery period. 相似文献
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Jiange Qian MD Wenzhong Li PhD Guocheng Zhang MD Liangbin Yan MS Wei Sun PhD † 《Dermatologic surgery》2005,31(1):23-26
BACKGROUND: Preservation of hair follicle units for the purpose of delayed transplant will help us graft thousands of hair grafts at one session, even in a clinic with fewer assistants and less equipment. OBJECTIVE: This study was undertaken to evaluate and compare the viability of hair follicle units preserved at 0 and 4 degrees C for various periods. MATERIALS AND METHODS: Cell cultures and transplant of hair follicle units into athymic mice were performed. RESULTS: Outer root sheath cells could be cultivated in 96% (0 degrees C group) and 92% (4 degrees C group) of the hair follicles after 24 hours of preservation, whereas 85% (0 degrees C group) and 79% (4 degrees C group) of the follicles implanted into the mice regrew well after the same period of preservation. Then, in both the 0 degrees C and the 4 degrees C group, these rates decreased significantly with length of preservation in cell cultures and mice transplant; however, 0 degrees C seems better than 4 degrees C for preservation of grafts (p<.05). CONCLUSION: Grafts are better preserved at 0 degrees C instead of 4 degrees C. When delayed transplant is an option, it should be completed within 24 hours and no later than 48 hours. 相似文献