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51.
In order to analyze the effect of a high local concentration of macrophage colony-stimulating factor (M-CSF; CSF-1) on tumor growth, the plasmacytoma cell line J558L was transfected with the human M-CSF gene and injected into syngeneic BALB/c mice. In contrast to the parental tumors, M-CSF transfectants were heavily infiltrated by macrophages as evidenced by immunohistochemistry with antibodies to Mac-1 and Mac-3 and by isolation of the macrophages from the tumor. Nevertheless, tumor growth was only slightly affected by M-CSF and M-CSF-producing cells grew as tumor in all cases. The growth retardation of M-CSF-producing cells varied depending on the experiment and seemed to be due to an indirect effect because the growth rate of the cells in vitro had not changed upon gene transfer. Attempts to activate the tumor-infiltrating macrophages for tumor suppression by systemic application of interferon-γ and/or lipopolysaccharide were not successful. Altogether, our results suggest that M-CSF is a potent chemoattractant for macrophages in vivo but alone is not sufficient to activate these macrophages for tumoricidal activity.  相似文献   
52.
Carcinoembryonic antigen (CEA) was purified from primary tumour or from hepatic metastases obtained from ten cases of carcinoma of the colon. In nine cases the blood group antigens A, B, Lea or Leb were detected in CEA preparations by the binding of 125I-labelled CEA by blood group antibodies. The extent of binding appeared to preclude simple contamination of CEA preparations by blood group glycoprotein. In all cases the blood group antigens detected were consistent with the patients' known blood groups. Blood group I and i activities were not detected.

It is concluded that the determinants of A, B and Lewis antigens and of CEA share the same glycoprotein carrier molecules.

  相似文献   
53.
The WAGR contiguous gene deletion syndrome is a combination of Wilms tumor, Aniridia, Genito-urinary abnormalities, and growth and mental retardation which is invariably associated with an 11p13 deletion. We report two monozygotic twins and a third, unrelated patient with WAGR syndrome and additional clinical features not usually associated with WAGR. Both twins had developmental delay, growth deficiency, severe ocular involvement (nystagmus, aniridia, cataracts), atrial septal defect and two uncommon findings: agenesis of the corpus callosum and duplication of the halluces. One twin developed Wilms tumors aged 19 months while her sister remained tumor free by the age of 6.5 years. The singleton patient showed typical WAGR syndrome and preaxial hallucal polydactyly. Molecular cytogenetic studies refined the identification of the extent of the deleted segments, which were not identical in the two families. The two deletions included the PAX6 and WT1 genes as previously reported in typical WAGR patients. The unusual anomalies described in this report, may represent the expression of low penetrant traits associated with haploinsufficency of one or more of the genes present in the deletion (PAX6 is expressed in CNS) or may indicate epistatic influences of modifier genes on the expression of gene(s) present in the WAGR region.  相似文献   
54.
Convenient and economical assays capable of screening many compounds are vital to advance the development of drug therapy. This is particularly important for many of the infections that occur mainly in the Third World. The development of such a spectrofluorometric assay for the protozoan parasite Leishmania is presented here. Using multimeric (four monomers) green fluorescent protein (GFP), Leishmania amazonensis promastigotes were generated with brightness measurable in 96-well microtiter plates. The promastigotes maintained the parental characteristics, were infective to murine macrophages and to mice, and the level of GFP fluorescence corresponded to the number of inoculated cells. The feasibility of using this assay for testing drugs kinetically and in a concentration-dependent manner, under microplate culture condition, was demonstrated with amphotericin B and the herbicide oryzalin, respectively. This assay is the first to allow a real-time analysis of antileishmanial agents with live promastigotes. The method of expressing multimeric GFP for in vitro drug screening is likely to be extendable to many species of parasitic protozoa.  相似文献   
55.
Left ventricular assist device (LVAD) implantation is frequently complicated by B-cell activation and allosensitization, posing a significant risk to successful transplant outcome. This study investigated whether B-cell hyperreactivity and alloantibody production in LVAD recipients involves T-cell dependent pathways. T-cell calcium flux and nuclear translocation of NFATc were used to determine states of T-cell activation. Flow cytometry was used to assess human T- and B-cell activation after culture with LVAD-derived biomaterial particles. Sera from LVAD recipients and controls were tested for the presence of anti-HLA antibodies, and for soluble CD40 ligand. LVAD-derived biomaterial induced rapid and sustained calcium flux into normal T cells, resulting in calcineurin-dependent nuclear translocation of NFATc. This resulted in increased T-cell expression of CD40 ligand and subsequent B-cell activation, which was reduced by inhibitors of T-cell activation (CsA or anti-CD25 mAb) or by anti-CD40 ligand mAb. LVAD recipients demonstrated higher frequencies of anti-HLA antibodies and serum levels of soluble CD40 ligand compared with heart failure controls. The results indicate that exposure of human mononuclear cells to LVAD-derived biomaterial leads to T-cell dependent B-cell activation via CD40--CD40 ligand interaction, and suggest that treatment with calcineurin inhibitors or monoclonal antibodies against either CD25 or CD40 ligand could be effective at preventing B-cell hyperreactivity and allosensitization after LVAD implantation.  相似文献   
56.
While the appropriate method for the investigation of female infertility continues to be debated, the timing of the investigation has received less attention. The current approach is time-consuming, and paradoxically may lead to overtreatment as well as undertreatment. Recent findings on fecundity and the conception window in humans have important implications for the timing of the investigation of female infertility. The findings support the view that fertility-oriented intercourse may have a major impact in reducing the time to pregnancy. Procedures for the investigation of female infertility are becoming less invasive and more accurate, while the therapies for infertility are more effective. It is proposed that under appropriate circumstances female infertility should be investigated after 6 months of fertility-oriented intercourse.  相似文献   
57.
Influence of kallidin-10 on renal function   总被引:1,自引:0,他引:1  
  相似文献   
58.
This study tried to differentiate the consequences of chronic hypoxia on the electrophysiological and physiological properties and the histological characteristics of slow and fast muscles in rats. Animals inhaled a 10% O2 concentration for a 1-month period. Then, slow [soleus (SOL)] and fast [extensor digitorum longus (EDL)] muscles were analyzed in vitro by physiological and electrophysiological measurements and histological analyses. The results were compared to those obtained in corresponding muscles of an age-matched normoxic group. After exposure to hypoxia: (1) in SOL, there was a tendency to elevated Fmax, a significant increase in twitch force and tetanic frequency and a shortening of M-wave duration, and a reduced percentage of type I fibres, whereas the proportion of type IIa fibres doubled; (2) in EDL, Fmax and tetanic frequency were lowered, the muscle became less resistant to fatigue, and the proportion of type IId/x fibres was halved. Then, after 1 month of hypoxia, in the SOL muscle, both the contractile and histological properties resemble those of a fast muscle. By contrast, the EDL became slower, despite its histology was modestly affected. Reduced muscle use in hypoxia could explain the tendency for deteriorating adaptations in EDL, and the faster properties of SOL could result from hypoxia-induced inhibition of the growth-related fast-to-slow shift in muscle fibre types.  相似文献   
59.
The close genetic relationship of human and animal strains of norovirus has raised the possibility of transmission of noroviruses from animals to humans and may explain the emergence of certain norovirus strains. To assess if exposure to bovine noroviruses (NoV) might result in infection in humans, an enzyme immunoassay (EIA) was designed and validated in order to detect antibodies against bovine norovirus. This and two other EIAs were used to test sera from 210 veterinarians and 630 matched population controls for IgG and IgA antibodies to recombinant capsid protein of bovine NoV (rBoV), Norwalk virus (rNV), and Lordsdale virus (rLDV). Of 840 participants, IgG reactivity to rBoV was found in 185 (22%), to rNV in 638 (76%) and to rLDV in 760 (90%). IgG reactivity to rBoV was more common in veterinarians (58/210: 28%) than in controls (127/630: 20% [P = 0.03]). IgA reactivity to rBoV was similar in both veterinarians and controls. Cross-reactivity of IgA and IgG antibodies to rBoV and rNV was seen, but 26% of all specimens positive rBoV antibodies showed high IgG reactivity to rBoV but low reactivity to rNV, suggesting a specific response to bovine antigen. No evidence of overall cross-reactivity of antibodies to rBoV and rLDV was seen. Among veterinarians, youth spent on farm (Odds Ratio [OR] = 1.8) and membership of the bovine practitioners' society (OR = 2.7) were significantly associated with IgG seroreactivity to rBoV. These data indicate that bovine strains of NoV may infect humans though less frequently than human strains.  相似文献   
60.
The field of cancer communication has undergone a major revolution as a result of the Internet. As recently as the early 1990s, face-to-face, print, and the telephone were the dominant methods of communication between health professionals and individuals in support of the prevention and treatment of cancer. Computer-supported interactive media existed, but this usually required sophisticated computer and video platforms that limited availability. The introduction of point-and-click interfaces for the Internet dramatically improved the ability of non-expert computer users to obtain and publish information electronically on the Web. Demand for Web access has driven computer sales for the home setting and improved the availability, capability, and affordability of desktop computers. New advances in information and computing technologies will lead to similarly dramatic changes in the affordability and accessibility of computers. Computers will move from the desktop into the environment and onto the body. Computers are becoming smaller, faster, more sophisticated, more responsive, less expensive, and--essentially--ubiquitous. Computers are evolving into much more than desktop communication devices. New computers include sensing, monitoring, geospatial tracking, just-in-time knowledge presentation, and a host of other information processes. The challenge for cancer communication researchers is to acknowledge the expanded capability of the Web and to move beyond the approaches to health promotion, behavior change, and communication that emerged during an era when language- and image-based interpersonal and mass communication strategies predominated. Ecological theory has been advanced since the early 1900s to explain the highly complex relationships among individuals, society, organizations, the built and natural environments, and personal and population health and well-being. This paper provides background on ecological theory, advances an Ecological Model of Internet-Based Cancer Communication intended to broaden the vision of potential uses of the Internet for cancer communication, and provides some examples of how such a model might inform future research and development in cancer communication.  相似文献   
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