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991.
A new model for the subcellular basis of parotid secretion is presented in this article. GM(1)-ganglioside, typically found in neural tissues, is shown to be abundant in the parotid gland. This ganglioside may play a central role in membrane turnover mechanisms underlying exocytosis/endocytosis in its role as a promoter of membrane fusion or a fusogen. The lysosome and lysosomal hydrolases also play a central role in this model in catabolism of GM(1)-ganglioside. Consequently, high levels of the lysosomal hydrolase acidic beta-galactosidase are demonstrated in the salivary gland. GM(1)-gangliosidosis of the parotid glands, as described in mice, appears to be the first single-gene heritable disease found so far in the salivary glands.  相似文献   
992.
The treatment of salivary gland malignant neoplasms is challenging because of their infrequency, their unpredictable and varied biologic behavior, and their prolonged risk of recurrence. This article covers the pathophysiology of malignant neoplasms of the salivary glands. Emphasis is placed on the more common neoplasms. Histologic classification and management of neoplasms are also reviewed in this article.  相似文献   
993.
This study reports on the outcomes of an investigation designed to evaluate competing accounts of the nature of the grammatical limitations of children with specific language impairment (SLI) with a new comprehension measure involving well-formedness judgments. It is a follow-up to the longitudinal study of Rice, Wexler, and Hershberger (1998), which reported on the production of grammatical morphemes by young children with SLI and 2 control groups of children, one at equivalent levels of mean length of utterance at the outset of the study, the other of equivalent age. In this investigation, we report on grammaticality judgment measures collected from the same 3 groups of children over a period of 2 years for 5 times of measurement. It is the first longitudinal study of grammaticality judgments of children with SLI. The findings show that children's grammatical judgments parallel their productions: Children with SLI can make fine-tuned grammatical judgments to reject morphosyntactic errors they are unlikely to commit, whereas they accept morphosyntactic errors that they are likely to produce. The findings support the extended optional infinitive (EOI) account of morphosyntactic limitation based in underlying grammatical representations and do not support accounts of input processing deficits or production constraints.  相似文献   
994.
目的:分离培养和鉴定大鼠骨髓间充质干细胞.方法:分离SD青年大鼠股骨,L-DMEM冲洗骨髓腔,制备细胞悬液接种培养,消化传代纯化细胞.传代的骨髓间充质干细胞进行增殖曲线、克隆形成能力测定,用免疫组化检测增殖细胞vimentin、laminin的表达.结果:传代的细胞在培养第1~2天为潜伏期,第3~6天是细胞快速增殖期,第6天达高峰,第 9天后速度减慢,进入平台期,并且随传代次数的增加,细胞增殖速度逐渐下降.随传代次数增多,克隆形成能力逐渐下降.第5代以后细胞基本纯化为骨髓间充质干细胞,细胞呈长梭形.免疫组化检测增殖细胞vimentin表达阳性、laminin表达阴性.结论:本实验方法能有效扩增大鼠骨髓间充质干细胞,而且简单易行.  相似文献   
995.
996.
The cancer/testis antigen NY‐ESO‐1 contains an immunodominant HLA‐A2‐binding peptide (SLLMWITQC), designated S9C, an attractive target for vaccination against several human cancers. As cysteine contains a reactive ? SH, the oxidation status of exogenous synthetic peptide is uncertain. We have designed tolerance‐breaking DNA fusion vaccines incorporating a domain of tetanus toxin fused to tumor‐derived peptide sequences (p.DOM‐peptide), placed at the C‐terminus for optimal immunogenicity. In a “humanized” HLA‐A2 preclinical model, p.DOM‐S9C primed S9C‐specific CD8+ T cells more effectively than adjuvanted synthetic peptide. A DNA vaccine encoding the full NY‐ESO‐1 sequence alone induced only weak S9C‐specific responses, amplified by addition of DOM sequence. The analog peptide (SLLMWITQL ) also primed peptide‐specific CD8+ T cells, again increased by DNA delivery. Importantly, T cells induced by S9C‐encoding DNA vaccines killed tumor cells expressing endogenous NY‐ESO‐1. Only a fraction of T cells induced by the S9L‐encoding DNA vaccines was able to recognize S9C and kill tumor cells. These data indicate that DNA vaccines mimic posttranslational modifications of ? SH‐containing peptides expressed by tumor cells. Instability of synthetic peptides and the potential dangers of analog peptides contrast with the ability of DNA vaccines to induce high levels of tumor‐lytic peptide‐specific CD8+ T cells. These findings encourage clinical exploration of this vaccine strategy to target NY‐ESO‐1.  相似文献   
997.
998.
This study examined the degree to which pain catastrophizing and pain-related fear explain pain, psychological disability, physical disability, and walking speed in patients with osteoarthritis (OA) of the knee. Participants in this study were 106 individuals diagnosed as having OA of at least one knee, who reported knee pain persisting for six months or longer. Results suggest that pain catastrophizing explained a significant proportion (all Ps  0.05) of variance in measures of pain (partial r2 [pr2] = 0.10), psychological disability (pr2 = 0.20), physical disability (pr2 = 0.11), and gait velocity at normal (pr2 = 0.04), fast (pr2 = 0.04), and intermediate speeds (pr2 = 0.04). Pain-related fear explained a significant proportion of the variance in measures of psychological disability (pr2 = 0.07) and walking at a fast speed (pr2 = 0.05). Pain cognitions, particularly pain catastrophizing, appear to be important variables in understanding pain, disability, and walking at normal, fast, and intermediate speeds in knee OA patients. Clinicians interested in understanding variations in pain and disability in this population may benefit by expanding the focus of their inquiries beyond traditional medical and demographic variables to include an assessment of pain catastrophizing and pain-related fear.  相似文献   
999.
The impact of sexual harassment on girls' and women's developing concept of their body and self has rarely been examined with the goal of expanding our understanding of weight and shape preoccupation. In this paper we examine how this pervasive form of violence contributes to young women's uneasiness about their developing bodies and results in a disruption of healthy female development that often gets played out in disordered patterns of eating and intense body monitoring.  相似文献   
1000.
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