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61.
Reliable and valid longitudinal residential histories are needed to assess interventions to reduce homelessness and increase community tenure. This study examined the test‐retest reliability, sensitivity to change, and concurrent validity of the Residential Time‐Line Follow‐Back (TLFB) Inventory, a method used to record residential histories in the Collaborative Program to Prevent Homelessness (n = 1,381). The Residential TLFB Inventory yielded temporally stable aggregate measures of duration in residential categories, and it revealed significant differences in change over time when contrasting study groups. A comparison of agency and participant data at one site.  相似文献   
62.
Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied MHC class II molecules and invariant chain inducibility on four class II negative mouse pro- B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative. As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only. These data suggest that the induction of class II and invariant-chain genes are subject to regulation throughout B-cell differentiation.  相似文献   
63.
Rearrangements or deletions of chromosome 17 are the most frequentlyobserved genetic changes identified in breast tumors. Molecularanalyses suggest that in addition to the p53 gene on 17p13.1there may be at least three other tumor suppressor genes onchromosome 17 involved in breast cancer. Regions of loss ofheterozygosity (LOH) identified on 17p13.3 and 17q12-qter occurfrequently in breast tumors, and the BRCA-1 gene has been mappedto 17q21 by genetic linkage analysis. Here we provide biologicalevidence for the presence of a growth suppressor gene(s) onchromosome 17 that results In the In vitro growth suppressionof the p53 wild-type MCF 7 breast cancer cell line. We haveIntroduced a normal chromosome 17 into MCF 7 cells by microcellmediatedchromosome transfer (MMCT), and demonstrate that cells growtharrest before 10 to 12 population doublings. In contrast, theintroduction of a normal chromosome 13 had no effect upon growthof these cells either In vitro or In vivo. These data providedirect functional evidence for the presence of a growth suppressorgene(s) on chromosome 17, which is not p53, and which may representone of several gene(s) that play a critical role in the developmentof breast cancer.  相似文献   
64.
A previously unreported isodicentric chromosome 18 was discovered in an abnormal infant boy whose mosaic karyotype was 46, XY/46,XY,–18, + idic(18)(q12.2). His constellation of congenital anomalies was typical of the 18q-syndrome. The clinical and cytogentic characteristics of this patient are reported, and the literature concerning isochromosomes of 18 is reviewed.  相似文献   
65.
Preface     
Valerie J. Lund 《Allergy》1994,49(S19):4-4
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66.
Summary Isatin -thiosemicarbazone (ITSC) is well known for its chemoprophylactic activity against certain poxvirus infections. The influence of 20 M ITSC on the development of neurovaccinia virus particles in infected embryo rabbit kidney cells has been studied by electron microscopy. It is shown that ITSC exerts an intracellular effect, permitting the formation of immature and abnormal forms, but preventing the normal development of these to give mature infective virus particles. The effects are compared with the normal development of mature virus particles as observed by us and as described by other authors from their electron microscopy studies.  相似文献   
67.
68.
Transgenic Mice as an in vivo Model for Self-Reactivity   总被引:1,自引:0,他引:1  
  相似文献   
69.
70.
Compliance with oral theophylline therapy in asthmatic children   总被引:1,自引:0,他引:1  
Serum theophylline levels were obtained from 111 children on continuous theophylline therapy when seen in the emergency department for acute episodes of wheezing. Sixty-six percent of patients were at least partially compliant and only 34% were noncompliant in medication taking on the basis of a serum theophylline level of less than 5 micrograms/mL. The main factors associated with compliance were type of primary care source, whether the patient had difficulty keeping appointments, and the relationship of the caretaker to the patient.  相似文献   
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