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R I Cruz D M Anderson E G Armstrong W R Moyle 《The Journal of clinical endocrinology and metabolism》1987,64(3):433-440
When hCG adsorbs to surfaces, including membranes from tissues that lack specific hCG receptors, it adsorbs with a particular orientation. Some sites on the alpha- and beta-subunits project away from the surface and can be detected with radiolabeled monoclonal antibodies. Other epitopes, which are located on a region on the hormone that presumably contacts the surface, lose their ability to bind antibody. Using antibodies specific for epitopes on hCG which remain exposed and can be detected when the hormone is adsorbed to rat brain homogenates, we found hCG or closely related substances bound to progestational decidual tissues. Immunologically reactive material adsorbed to the decidual tissue increased and decreased in parallel with the serum levels of hCG throughout pregnancy. Binding of labeled monoclonal antibody to substances similar or identical to hCG in other tissues, including placenta and fetal lung, but not red cells, also was identified. Unlike material adsorbed to decidual tissues, receptor-bound hCG was not recognized by any of our alpha-subunit-specific antibodies. This finding suggests either that the adsorbed hormone has a different orientation than receptor-bound hormone or that the adsorbed hormone has dissociated into subunits. These studies represent the first detection of nonreceptor binding of hCG or related molecules to tissues lacking receptors or presumed not to synthesize the hormone. The role of nonreceptor-bound hCG, if any, is unknown. Other than its effects on stimulation of luteal steroidogenesis during early pregnancy, the role of hCG during most of pregnancy has not been determined. Conceivably, the nonreceptor binding we identified is related to a role for hCG in pregnancy that is not associated with an action on the ovarian LH receptor. 相似文献
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Jason P. Glover DPM Christopher F. Hyer DPM Gregory C. Berlet MD Thomas H. Lee MD 《The Journal of foot and ankle surgery》2008,47(3):237-242
In our retrospective study, we report the objective results of the Mau osteotomy in the treatment of hallux valgus. We reviewed the results of 24 cases of moderate to severe hallux valgus deformities corrected with the Mau osteotomy of the first metatarsal combined with a distal soft-tissue procedure. Follow-up was possible in 24 cases. Preoperatively the mean hallux valgus and first intermetatarsal angles were 31.3 degrees and 16.6 degrees respectively, and were corrected postoperatively to an average of 13.00 degrees+/-7.15 degrees and 9.80 degrees+/-2.43 degrees respectively (P< .001). In the sagittal plane, the first metatarsal was shortened by an average of 2.00 mm. Two (8.3%) cases had dorsal elevation of the osteotomy fragment. Complications included 3 recurrences of the deformity, 1 frank nonunion, 8 dorsal cortical nonunions, 5 cases of undercorrection, and 1 case of broken hardware that was present in the nonunion that went on to revision. There were no superficial or deep infections, and no cases of transfer metatarsalgia were noted. In this series, the use of an oblique first metatarsal osteotomy with a dorsal shelf resulted in reliable and powerful correction of the first intermetatarsal angle in patients with moderate to severe hallux valgus. Particular attention should be paid to severe IM angles and the possibility of undercorrections. Despite ambulation postoperatively, the Mau osteotomy minimized dorsal malunion and the incidence of transfer metatarsalgia. LEVEL OF CLINICAL EVIDENCE: 4. 相似文献
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PURPOSE: The pharmacology of methamphetamine is reviewed, and the effects of methamphetamine use on oral health are described. SUMMARY: Methamphetamine is a highly addictive amphetamine analogue, initially synthesized in 1919. Illicit methamphetamine use leads to devastating effects on health, particularly the dentition. Illegal production of methamphetamine has skyrocketed in recent years, as have the number of users. The chief complaint of methamphetamine users is xerostomia. Without the protective effects of saliva, caries development in these patients is rampant. The typical pattern of decay involves the facial and cervical areas of both the maxillary and mandibular teeth, with eventual progression to frank coronal involvement. The acidic substances used to manufacture this drug have also been implicated as a cause of tooth decay and wear in users, as has bruxism as a result of drug-induced hyperactivity. When possible, these patients should be referred to a dentist to improve their oral health status and minimize the potential for adverse cardiovascular sequelae. Other preventive measures for methamphetamine users include stimulating saliva flow and increasing fluoride supplementation. Pharmacists should also counsel users to avoid carbohydrate-rich soft drinks in favor of water. Oral moisturizers may also be effective. CONCLUSION: Methamphetamine use causes xerostomia secondary to sympathetic central nervous system activation, rampant caries caused by high-sugar intake in the absence of protective saliva, and bruxism as a result of hyperactivity. Practitioners should know how to recognize the signs of and manage the oral health of patients with a history of methamphetamine use. 相似文献
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Ganapathy A Prasad Kenneth K Wang Lori S Lutzke Jason T Lewis Schuyler O Sanderson Navtej S Buttar Louis M Wong Kee Song Lynn S Borkenhagen Lawrence J Burgart 《Clinical gastroenterology and hepatology》2006,4(2):173-178
BACKGROUND & AIMS: The aim of this study was to assess the validity of frozen section analysis of endoscopic mucosal resection (EMR) specimens from Barrett's esophagus as compared with permanent sections for the detection of neoplasia. Frozen sections help to give immediate feedback for surgical procedures. It has not been determined whether EMR can be adequately interpreted by using frozen sections to aid endoscopists in completely resecting neoplastic lesions. METHODS: EMR specimens from Barrett's esophagus with high-grade dysplasia (HGD) and/or carcinoma were tested by frozen section. Pathologists evaluated EMR specimens for the depth of invasion as well as the appearance of clear margins of resection. The kappa statistic was calculated to assess the degree of agreement between the frozen section and permanent section diagnoses. RESULTS: Twenty-three consecutive patients underwent 30 EMRs with frozen section diagnosis. Frozen section revealed a carcinoma in 7 specimens (23%) and dysplasia in 20 (66%). Permanent sections found carcinoma in 8 specimens (26%), dysplasia in 19 specimens (63%), and normal or nondysplastic Barrett's esophagus in the remainder. The kappa statistic for the depth of invasion of EMR specimens was 0.93 (near perfect agreement). The kappa statistic for the margins of the EMR specimens was 0.80 (excellent agreement). CONCLUSIONS: This study indicated that frozen section analysis of esophageal EMR specimens is valid as compared with permanent section. This technique might allow rapid evaluation about the degree and depth of involvement of cancers. This allows physicians to make decisions regarding further therapy if margins are involved or decrease the use of EMR for histologically benign-appearing lesions. 相似文献