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61.
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PURPOSE: To characterize novel pharmaceutical organogels based on the self-assembly of L-alanine derivatives in hydrophobic vehicles. METHODS: The gelation properties of N-lauroyl-L-alanine (LA) and N-lauroyl-L-alanine methyl ester (LAM) were investigated in the presence of various solvents. Gel-sol and sol-gel transitions were evaluated by the inverse flow method, and gelation kinetics were determined by turbidimetry. The in vitro release kinetics of labeled dextran physically dispersed in the oil-based organogel was assessed in phosphate-buffered saline. In situ formation of the implants was evaluated in rats by subcutaneously injecting a solution containing LAM, an oil, and a water-diffusible inhibitor of self-assembly (ethanol). RESULTS: The LAM-containing formulations showed a hysteretic gelling behavior with transition temperatures between 10 and 55 degrees C. Gelation kinetics exhibited a lag time of 10 and 30 min at 25 and 37 degrees C, respectively. In vitro, fluorescein isothiocyanate-dextran was released from the gel in a sustained manner with less than 6% released after 20 days. The addition of ethanol to the LAM/oil mixture inhibited gelation and allowed subcutaneous injection of the solution at room temperature. After injection, ethanol diffusion led to the formation of a solid implant. CONCLUSIONS: Low-molecular weight self-assembling organogelators may allow the preparation of novel in situ-forming hydrophobic implants.  相似文献   
63.
OBJECTIVE: To investigate the role of different cellular types (epithelial and stromal endometrial cells and peritoneal cells) in the ectopic implantation of endometrium and to evaluate the importance of endocrine environment on the adhesion of endometrial cells to the peritoneum. DESIGN: Experimental prospective study. SETTING: University hospital, department of cell biology. ANIMAL(S): One hundred one nude mice. INTERVENTION(S): Monolayer culture of human epithelial and stromal endometrial cells obtained from patients undergoing hysterectomy or laparoscopy for benign disease. Intraperitoneal injection of cells into nude mice. MAIN OUTCOME MEASURE(S): Two weeks after cell injection, adhesion of endometrial cells was evaluated by histological and immunohistochemical examination. RESULT(S): Mixed cultures of stromal and epithelial cells, but not purified epithelial or stromal cells alone, adhered to the mouse peritoneum and led to endometriotic-like nodules. Pretreatment of cells with estrogen alone or with estrogen and progestin resulted in a higher percentage of animals developing endometriotic-like nodules, whereas treatment with progestin alone did not affect endometriotic implantation. CONCLUSION(S): Our data indicate that the success of endometrial cell implantation is dependent on the cooperativeness between stromal and epithelial endometrial cells, as well as on the endocrine environment of endometrial cells, but not that of recipient animals. The results emphasize the role of both endometrial cell types for ectopic implantation.  相似文献   
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Sulcus vocalis is described as a groove at the free edge of the vocal fold. Different types have been described: sulcus type I is superficial and may be considered as moreless physiologic. Sulcus type IIa corresponds to a kind of vergeture along the margin of the vocal fold. Its deepness is variable but sulcus vergeture may involve deeper layers of the lamina propria. Sulcus type IIb or pounch may be considered as an open cyst. Sulcus lead to a complex glottic dysfunction with, in the same time, a glottal leakage responsible for the breathy component of the dysphonia and a stiffness of the free edge responsible for the roughness. Diagnosis may be difficult even with the help of stroboscopy and finally is sometimes done only under general anesthesia. Etiology remains controversial and the authors present arguments for each theory, acquired or congenital. Treatment options include phonosurgery and speech therapy but phonosurgery gives results often disappointing and surgical treatment must be indicated prudently and patient must be intensively informed on what he or she can expect from the treatment that is mainly an increase of the loudness of the voice.  相似文献   
66.
Massive sequence comparisons as a help in annotating genomic sequences.   总被引:1,自引:0,他引:1  
An all-by-all comparison of all the publicly available protein sequences from plants has been performed, followed by a clusterization process. Within each of the 1064 resulting clusters-containing sequences that are orthologous as well as paralogous-the sequences have been submitted to a pyramidal classification and their domains delineated by an automated procedure à la. This process provides a means for easily checking for any apparent inconsistency in a cluster, for example, whether one sequence is shorter or longer than the others, one domain is missing, etc. In such cases, the alignment of the DNA sequence of the gene with that of a close homologous protein often reveals (in 10% of the clusters) probable sequencing errors (leading to frameshifts) or probable wrong intron/exon predictions. The composition of the clusters, their pyramidal classifications, and domain decomposition, as well as our comments when appropriate, are available from http://chlora.infobiogen.fr:1234/PHYTOPROT.  相似文献   
67.
Different policies relating to the employment of disabled people coexist in France. They rely on various mechanisms, such as quotas, non-discrimination, professional rehabilitation that corresponds to concurrent, or even antagonist, definitions of disability and participation in the labor market. Based on two original qualitative sociological surveys conducted by semi-structured interviews, this article explores how disability officers grasp, or do not grasp, the different legal tools available to implement employment policies for people with disabilities in public sector work organizations. Despite the strong persistence of an individual, medical, and defective approach to disability in employment, we show that disability officers strive to build a more ambitious, proactive, and systemic policy. They are sensitive to the environmental dimension of disability and to the prevention of disability at work, but do not make reference to the antidiscrimination law and its injunction to pursue equality and inclusion.  相似文献   
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BackgroundSubretinal fluid is a risk factor for growth and malignant transformation of choroidal naevi, however it is unclear if this applies to subclinical fluid that is only detectable by optical coherence tomography (OCT). The objective of this study was to determine the prevalence and associations of subclinical but OCT-detectable subretinal fluid over choroidal naevi.MethodsCross-sectional study of 309 consecutive cases of choroidal naevi imaged by OCT between July 2017 to January 2019. Multicentre international study involving ten retinal specialist centres. All patients presenting to retinal specialists had routine clinical examination and OCT imaging. The prevalence of subclinical OCT-detectable subretinal fluid over choroidal naevi and its associations with other features known to predict growth and malignant transformation were noted and analysed.ResultsOf 309 identified consecutive cases, the mean patient age was 65 years, 89.3% of patients were Caucasian and 3.9% were Asian. The prevalence of subclinical but OCT-detectable subretinal fluid associated with choroidal naevi was 11.7% (36/309). Naevi with fluid were associated with larger basal diameters, greater thickness, presence of a halo, orange pigmentation, hyperautofluorescence, and hypodensity on B-scan ultrasonography.Conclusion and relevanceOf choroidal naevi where subretinal fluid is not visible on clinical examination, 11.7% demonstrate subretinal fluid on OCT scans. These naevi more commonly exhibit features known to be associated with growth and transformation to melanoma. The presence of subclinical OCT-detectable fluid over choroidal naevi may assist in their risk stratification.Subject terms: Risk factors, Uveal diseases, Eye manifestations  相似文献   
70.
BACKGROUND: Compressive hematoma after thyroidectomy is a rare complication (1%) but can potentially be severe. The aim of this study was to search for risk factors, in particular the use of anticoagulants or antiplatelet medication, and to see if the delay of hematoma formation would require 1-day surgery performed in a careful manner. MATERIALS AND METHODS: Retrospective review of 6,830 patients undergoing thyroidectomy in a single institution (1991 to 2006) identified 70 patients with hematomas requiring reoperation. Case controls (210 patients) were matched for age, gender, year of operation, type of thyroid disease, and type of operation. The notion of anticoagulant or antiplatelet medication was particularly studied. The delay of hematoma formation and the cause of bleeding were studied in univariate analysis by a chi-squared test and a Fischer's test. RESULTS: In univariate analysis, the formation of hematoma is not related to age, gender, type of thyroid disease, or type of bleeding. The pre or intraoperatory administration of anticoagulant or antiplatelet medication did not influence hematoma formation. Thirty-seven hematomas (53%) presented within 6 h postoperatively, 26 (37%) between 7 and 24 h and seven (10%) beyond 24 h. CONCLUSION: Patients undergoing anticoagulant or antiplatelet treatment are not a high-risk population for hematoma formation. Forty-seven percent of the patients presented postoperative hematomas beyond 6 h postoperatively, leading to the conclusion that 1-day surgery is not safe.  相似文献   
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