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101.
102.
皮脂腺是皮肤重要的附属器。皮脂腺体外培养模型的建立为研究相关因子如细胞因子、生长激素及药物等对皮脂腺形态功能、生长发育及病理改变的作用提供了良好的平台。本文对皮脂腺细胞体外培养的实验方法、体外生长特性及影响皮脂腺细胞增殖分化的相关因素作简要综述。  相似文献   
103.
目的:观察右旋柠烯(d-limonene, DL)对大鼠乳腺增生及血雌激素和孕激素水平的影响.方法:苯甲酸雌二醇-黄体酮注射复制乳腺增生模型;HE染色观测乳腺组织学改变;放射免疫法检测血雌激素和孕激素水平.结果:右旋柠烯低、中、高剂量均能减少大鼠乳腺小叶数(9.20±2.32、6.90±1.20、6.10±1.37)、小叶腺泡数(8.20±1.75、6.10±2.23、5.10±1.52)和导管上皮层数(5.30±0.95、4.50±1.27、3.10±0.99),与模型组(分别为10.00±1.54、12.91±3.88和6.17±1.59)比较有显著性差异(P<0.01).右旋柠烯高、中剂量亦能降低血雌激素水平(28.35±2.16、25.17±1.25),提高孕激素水平(33.84±2.23、35.39±2.20),与模型组(分别为32.63±0.93, 31.77±1.48)比较差异显著(P<0.01),且对雌激素水平的影响有明显的量效关系.结论:右旋柠烯可抑制大鼠乳腺增生,降低血清雌激素水平、提高孕激素水平可能为其作用机制.  相似文献   
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Poly(lactic-co-glycolic acid) (PLGA) microparticles are used in various disorders for the controlled or sustained release of drugs, with the management of salivary gland pathologies possible using this technology. There is no record of the response to such microparticles in the glandular parenchyma. The purpose of this study was to assess the morphological changes in the parotid gland when injected with a single dose of PLGA microparticles. We used 12 adult female Sprague Dawley rats (Rattus norvegicus) that were injected into their right parotid gland with sterile vehicle solution (G1, n=4), 0.5 mg PLGA microparticles (G2, n=4), and 0.75 mg PLGA microparticles (G3, n=4); the microparticles were dissolved in a sterile vehicle solution. The intercalar and striated ducts lumen, the thickness of the acini and the histology aspect in terms of the parenchyma organization, cell morphology of acini and duct system, the presence of polymeric residues, and inflammatory response were determined at 14 days post-injection. The administration of the compound in a single dose modified some of the morphometric parameters of parenchyma (intercalar duct lumen and thickness of the glandular acini) but did not induce tissue inflammatory response, despite the visible presence of polymer waste. This suggests that PLGA microparticles are biocompatible with the parotid tissue, making it possible to use intraglandular controlled drug administration.  相似文献   
106.
Gene transfer offers a potential way to correct local and systemic protein deficiency disorders by using genes as drugs, so called gene therapeutics. Salivary glands present an interesting target site for gene therapeutic applications. Herein, we review proofs of concept achieved for salivary glands with in vivo animal models. In that context we discuss problems (general and salivary tissue-specific) that limit immediate clinical use for this application of gene transfer. Ongoing efforts, however, suggest that salivary glands may be suitable as gene therapeutic target sites for drug delivery in the near future.  相似文献   
107.
In patients suffering from oral cavity cancer surgical treatment is complex because it is necessary to remove carcinoma and lymph node metastasis (through a radical unilateral or bilateral neck dissection) and to reconstruct the affected area by means of free flaps. The saliva stagnation in the post-operative period is a risk factor with regard to local complications. Minor complications related to saliva stagnation (such as tissue maceration and wound dehiscence) could become major complications compromising the surgery or the reconstructive outcome. In fact the formation of oro-cutaneous fistula may cause infection, failure of the free flap, or the patient’s death with carotid blow-out syndrome. Botulinum injections in the major salivary glands, four days before surgery, temporarily reduces salivation during the healing stage and thus could reduce the incidence of saliva-related complications. Forty three patients with oral cancer were treated with botulinum toxin A. The saliva quantitative measurement and the sialoscintigraphy were performed before and after infiltrations of botulinum toxin in the major salivary glands. In all cases there was a considerable, but temporary, reduction of salivary secretion. A lower rate of local complications was observed in the post-operative period. The salivary production returned to normal within two months, with minimal side effects and discomfort for the patients. The temporary inhibition of salivary secretion in the post-operative period could enable a reduction in saliva-related local complications, in the incidence of oro-cutaneous fistulas, and improve the outcome of the surgery as well as the quality of residual life in these patients.  相似文献   
108.
Saliva is a complex fluid produced by 3 pairs of major salivary glands and by hundreds of minor salivary glands. It comprises a large variety of constituents and physicochemical properties, which are important for the maintenance of oral health. Saliva not only protects the teeth and the oropharyngeal mucosa, it also facilitates articulation of speech, and is imperative for mastication and swallowing. Furthermore, saliva plays an important role in maintaining a balanced microbiota. Thus, the multiple functions provided by saliva are essential for proper protection and functioning of the body as a whole and for the general health. A large number of diseases and medications can affect salivary secretion through different mechanisms, leading to salivary gland dysfunction and associated oral problems, including xerostomia, dental caries and fungal infections. The first part of this review article provides an updated insight into our understanding of salivary gland structure, the neural regulation of salivary gland secretion, the mechanisms underlying the formation of saliva, the various functions of saliva and factors that influence salivary secretion under normal physiological conditions. The second part focuses on how various diseases and medical treatment including commonly prescribed medications and cancer therapies can affect salivary gland structure and function. We also provide a brief insight into how to diagnose salivary gland dysfunction.  相似文献   
109.
Introduction and importanceAn adrenal metastasis is uncommon in esophageal cancer. Its diagnosis could be challenging if a percutaneous approach was inaccessible. Moreover, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), a useful adrenal sampling technique, is complicated by the luminal obstruction.Case presentationA patient with esophageal cancer accompanying by adrenal mass and established gastrostomy was described. The EUS-FNA of the adrenal lesion was successfully performed via the dilated gastrostomy tract. Adequate tissue for pathological examination was achieved, and the result indicated metastatic squamous cell carcinoma. Chemotherapy was started accordingly.Clinical discussionThis report described an uncommon event of adrenal metastasis of esophageal primary. Even though it is possible to perform EUS via the gastrostomy tract, performing EUS from an unusual direction might add some difficulty to an endoscopist, considering that EUS involves image pattern recognition in identifying structures. Thus, this technique should be operated by experienced EUS endoscopists.ConclusionGastrostomy can provide an enteral route for nutrition support in esophageal cancer patients. In addition, it could be an alternative EUS intervention portal when an esophageal stent is not accessible.  相似文献   
110.
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