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51.
With the ever-increasing evidence that the extracellular matrix (ECM) can stimulate tumor growth, it follows that inhibiting the synthesis of tumor-derived stroma may be a potential therapeutic target of cancer progression. The proline analog cis-hydroxyproline (CHP), an inhibitor of collagen deposition, was examined for its effects on the growth of clonal tumor cells that differentially produce type IV collagen and laminin. Two separate clones derived from rat mammary carcinoma cells that produce high and low amounts of type IV collagen and laminin were injected into the flanks of nude mice. Tumors in animals receiving CHP treatment grew faster than tumors in control animals receiving saline, although statistically not significant. Furthermore, upon administration of CHP to these clones in culture, increased proliferation rates of both cell types were observed. These results show that CHP is not useful in preventing stromal development and growth of rat mammary tumor xenografts. 相似文献
52.
Linney ID Buck IM Harper EA Kalindjian SB Pether MJ Shankley NP Watt GF Wright PT 《Journal of medicinal chemistry》2000,43(12):2362-2370
Novel, potent, and selective non-imidazole histamine H(3) receptor antagonists have been prepared based on the low-affinity ligand dimaprit (pK(I) 7.32 +/- 0.12, pK(B) 5.93 +/- 0.17). Detailed structure-activity studies have revealed that N-(4-chlorobenzyl)-N-(6-pyrrolidin-1-ylhexyl)guanidine (pK(I) 8.38 +/- 0.21, pK(B) 8.39 +/- 0.13), 30, and N-(4-chlorobenzyl)-N-(7-pyrrolidin-1-ylheptyl)guanidine (pK(I) 8.78 +/- 0.12, pK(B) 8.38 +/- 0.10), 31, exhibit high affinity for the histamine H(3) receptor. Antagonists 30 and 31 demonstrate significant selectivity over the other histamine, H(1) and H(2), receptor subtypes and a 100-fold selectivity in the sigma(1) binding assay. Compounds 30and 31 are the most potent, selective non-imidazole histamine H(3) receptor antagonists reported in the literature to date. 相似文献
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54.
The fatty acids in the human retina and the macular region were measured quantitatively (mole percent) by gas chromatography. The major fatty acids of the human retina and macula were palmitic, stearic, oleic, arachidonic, and docosahexaenoic. Surprisingly, there was much less docosahexaenoic acid in the macular region (15.9% of total) than in the peripheral retina (22.3% of total). There was a group of "other fatty acids," not any of the five major fatty acids, that were relatively more abundant in the macula (21.0% of total) than in the peripheral retina (10.7% of total). These results indicate that the human macula has a unique biochemical composition, which differs substantially from the peripheral retina. Establishment of the biochemical composition of the macula may be important for helping recognize possible changes associated with diseases such as age-related macular degeneration. 相似文献
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56.
After a brief review of literature, the authors report a case of the "Lasthénie de Ferjol" syndrome. From clinical observations, they establish theoretical landmarks and underline the necessity for searching the meaning. 相似文献
57.
By intra-adnexal injection of glucose in the rabbit embryo, we were able to stimulate all the anomalies associated with "Amniotic Disease". Since we were even able to obtain amniotic bands, this study provides an excellent experimental model of this disease. Resulting lesions occur early in development, corresponding to the first trimester of human gestation. All of the anomalies can ultimately be explained by the destruction of the most superficial cells: epiblastic cells of the embryo and the amnion, subjacent mesenchyme, and endothelial cells. The subsequent lack of interaction between these cells and the importance of the anatomical localizations of resulting hematomas can lead to the pathogenetic approach to this disease. In light of the present study, the disease appears to be caused by an external factor within the amniotic fluid. The exact nature of the destructive agent(s) remains a mystery in man. 相似文献
58.
Recovery from schizophrenia may involve persons developing a renewed sense of their illness, identity, agency, and worth within their life stories. To explore the requirements and challenges of psychotherapy that could facilitate this, we present a case study of a person with schizophrenia enrolled in treatment for over 19 months. Observed challenges to this process include the therapist's inclinations to "fix" the client, the client's own deficits and symptoms, and discomfort within the therapeutic relationship. Techniques to address these difficulties are presented, along with an objective means of assessing the treatment outcomes in terms of changes in narrative processes. 相似文献
59.
60.
Nissen SL Harris RW Jennings LJ Eggett DL Buck H 《International journal of audiology》2005,44(7):391-399
The aim of this investigation was to develop, digitally record, evaluate, and equate Mandarin trisyllabic words, which could then be used to measure the SRT. A selection of 90 frequently utilized trisyllabic words were digitally recorded by male and female talkers of Standard Mandarin and presented to 20 normally hearing subjects at 13 intensity levels (-10 to 14dB HL) in 2dB increments. Using logistic regression, psychometric functions were then calculated for all words. Twenty-four trisyllabic words with steep psychometric function slopes were selected, and their intensities were digitally adjusted to match the mean subject PTA (3.0 dB HL). The mean slopes for the 24 selected male and female trisyllabic Mandarin Chinese words were 11.3%/dB and 12.1%/dB, respectively. Thus we developed a list of words which were homogeneous with respect to audibility and slope. Digital recordings of the psychometrically equivalent trisyllabic words are available on compact disc. 相似文献