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81.
Hidrotic ectodermal dysplasia is a rare genodermatosis with clinical hallmarks of alopecia, nail dystrophy, and palmoplantar hyperkeratosis. This report calls attention to the first reported cases, to our knowledge, of hidrotic ectodermal dysplasia in a black mother and daughter.  相似文献   
82.
The safety of G-CSF and GM-CSF in adult and pediatric patients with ALL has been well established. In addition, prophylactic administration of G-CSF was shown to significantly accelerate neutrophil recovery in most clinical trials. This was associated with a substantially reduced incidence and duration of febrile neutropenia and of severe infections in selected high risk patients receiving multiple treatment cycles, whereas the clinical benefit appears to be negligible in patients at low risk of infectious complications. There is currently insufficient evidence to support the use of GM-CSF as an adjunct to treatment for ALL outside of clinical trials. Apart from patient characteristics and type of CSF, it has become evident that scheduling of growth factor administration in relation to the type of chemotherapy, and use of different study end points influence the clinical efficacy of HGF administration. Although no studies have so far shown that use of growth factors is associated with reduced mortality, higher complete remission rates or superior survival, improvements in other clinical endpoints, e.g. infection rate, duration of i.v. antibiotics, and length of hospital stays were frequently perceived as clinically important and felt to contribute substantially to the patient's quality of life. It will become increasingly important to select those patients likely to benefit from growth factor support and to identify additional predictive criteria. Scheduling of CSFs, e.g. early versus delayed and prophylactic versus interventional administration, the type of growth factor used and the duration of administration need to be optimized in the context of specific treatment protocols. Although myeloid growth factors presently can not be expected to have a major impact on overall treatment outcome in patients with ALL, they facilitate important incremental improvement; in supportive care when appropriately applied. As the remaining open questions are resolved, clinical benefits may be achieved consistently and with a favorable cost benefit ratio.  相似文献   
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The addition of organic acids (picric, oxalic, citric, or tartaric) to peptide and protein samples was found to significantly increase the yield of their quasi-molecular ions (QMI) in time-of-flight 252Cf plasma desorption mass spectrometry. The yield of the ions depended on the pKa of the acid added.  相似文献   
85.
PURPOSE: The mechanisms that underlie the clinical efficacy of melanoma vaccines are not well understood. We hypothesized that the type and strength of the immune response generated by CancerVax (John Wayne Cancer Institute, Santa Monica, CA), a polyvalent melanoma cell vaccine (PMCV), might be correlated with its effect on overall survival (OS). PATIENTS AND METHODS: Seventy-seven patients began PMCV therapy after complete surgical resection of distant metastatic melanoma. During the first two treatments, PMCV was administered with bacille Calmette-Guerin (BCG). Blood was drawn at 0, 2, 4, 8, and 12 weeks to measure serum titers of immunoglobulin G (IgG) and IgM antibodies against a tumor-associated 90-kd glycoprotein antigen (TA90) expressed on most melanoma cells, including those of PMCV. Cellular immune response to PMCV was assessed by delayed-type hypersensitivity (DTH). General immune competence was assessed by skin tests to purified protein derivative (PPD), mumps, and candida. RESULTS: Median follow-up time was 31.5 months. Within the first 12 weeks of PMCV immunotherapy, there was a significant increase in the anti-TA90 IgM (P=.0001) and IgG titers (P=.0001), and in the DTH response to PMCV (P=.0001). Univariate analysis showed that high anti-TA90 IgM titer and strong PMCV-DTH were associated with improved survival (P=.051 and .0173, respectively), whereas elevated anti-TA90 IgG was correlated with decreased survival (P=.0119). Multivariate analysis considering clinical variables and PMCV immune responses identified anti-TA90 IgM, anti-TA90 IgG, and PMCV-DTH as significant independent variables influencing survival following PMCV immunotherapy (P=.0342, .0105, and .0082, respectively). These responses to PMCV were not correlated with immune responses to BCG and therefore were not a manifestation of general immune competence for responses to unrelated antigens. The median survival time and 5-year survival rate were more than 76 months and 75%, respectively, if both anti-TA90 IgM and PMCV-DTH responses were strong (> or = 800 and > or = 7 mm, respectively; n=29); 32 months and 36%, respectively, if only one response was strong (n=35); and 19 months and 8%, respectively, if neither was strong (n=13) (P < .0001). CONCLUSION: PMCV induces both humoral and cell-mediated immune responses to melanoma-associated tumor antigens, the type and strength of which appear to be directly related to its therapeutic efficacy.  相似文献   
86.
Two convenient, practical routes to the synthesis of non-nucleotide bridged cyclic oligonucleotides have been developed. The first procedure included circularization of oligonucleotides by template-directed ligation on solid phase, while the second procedure involved preparation of a circular oligomer by non-template chemical ligation of a linear precursor in solution. Using these approaches, a series of single- and double-stranded cyclic oligonucleotides with non-nucleotide bridges has been synthesized.  相似文献   
87.
This study evaluated the early changes of maxillary alveolar arches of operated unilateral cleft lip and palate patients. Dental casts were available at four age increments. Triangular flap cheiloplasty was carried out at an early age. Two-stage palatoplasty by vomer flap and soft palate closure took place later. Prior to lip repair, the alveolar arches were classified according to the relationship between greater and lesser segments. Almost a quarter had overlap of the alveolar segments with no contact between the alveolar ridges at the cleft site; some had no overlap with contact of the alveolar segments in the cleft region; almost a quarter had both overlap of the alveolar segments and contact; and almost half had no overlap of the segments and the alveolar ridges were not in contact at the cleft site. After lip repair, the arch relationships were examined and the percentage of patients in each of the four groups indicated a moulding effect of lip repair on the alveolar segments. This moulding effect caused the alveolar segments in most patients to be in contact at the cleft site. Most of these also had segment overlap. All patients were re-examined shortly after palatal repair. The trend for segment overlap and contact continued after palate surgery. However, when all patients were seen at age 4, percentages of patients in each group indicated that previous overlap of segments improved to a more desirable nonoverlapped relationship in approximately half of the patients. The other half continued to demonstrate arch collapse, in excess of what would be considered ideal ridge relationship.  相似文献   
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To elucidate the extent and mechanisms of the first-pass metabolism of peptide drugs in the liver after oral administration, a liver perfusion study was performed in rats using metkephamid, a stable analogue of methionine enkephalin, and thyrotropin-releasing hormone (TRH), as model peptides. The fraction of intact metkephamid recovered after single-pass constant perfusion through rat liver reached steady-state very quickly, and it was concluded that metkephamid was hydrolysed enzymatically at the surface of hepatocytes or endothelial cells of microvessels, or both, rather than being taken up by hepatocytes. The fraction of metkephamid recovered intact was approximately 40% under protein-free conditions but increased to 70-75% on addition of bovine serum albumin (BSA) to the perfusate. The fraction of metkephamid bound to BSA was approximately 50% under these conditions, implying that only the free fraction of metkephamid in the plasma was metabolized in the liver. Calculations based on the tube model showed that approximately 30-35% of metkephamid absorbed from the intestine undergoes first-pass metabolism before entering the systemic circulation in-vivo. In contrast, the fraction of TRH metabolized in the liver was less than 10%, indicating a remarkably low contribution of first-pass metabolism to the bioavailability of TRH. These results show that hepatic first-pass metabolism of metkephamid contributes to its low systemic bioavailability. After intestinal absorption free metkephamid is rapidly hydrolysed on the surface of hepatocytes or endothelial cells, rather than being taken up by hepatocytes. This information has important implications in the oral delivery of many kinds of peptide.  相似文献   
90.
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