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91.
We previously conducted a study of 88 cases of prostate cancer in an attempt to identify potential prognostic biomarkers that can distinguish aggressive cases that must be treated immediately. Prostate cancer is a serious disease affecting men worldwide and compromises the quality of life of its patients. Biomarkers studied included chromosome 7 trisomy, chromosome 8 trisomy, and HER-2/neu oncogene amplification. These biomarkers were initially studied because trisomy 8 and oncogene amplification of the HER-2/neu gene have been reported in many other cancers, including those studied in this laboratory. In view of the fact that HER-2/neu amplification was not found to play a prominent role in the group of prostate cancer specimens that we studied, an exploration of other biomarkers was felt to be warranted. Thus, we began a pilot study of c-myc oncogene copy number in prostate cancer using the same protocol for fluorescent in situ hybridization and a direct-labeled SpectrumOrange LSI c-myc probe (Vysis, Inc., Downers Grove, IL) on formalin-fixed, paraffin-embedded tissue. From a total of 36 cases of prostate cancers successfully analyzed, we found 11 (31%) tumors exhibiting 3 or more positive signals for c-myc in 15% or more of the cells. Of these, only 7 tumors (19% of the total cases studied) had >/=3 signals in 20% or more of the cells. No case had >/=3 signals in 25% or more of the cells. Compared to other molecular probes tested, the c-myc signals were more faint and the quality of the preparation was less optimal than other tumor specimens that we previously studied. Based on the information available thus far, we conclude that an increased copy number in c-myc oncogene copy number was not a prominent finding in our cohort of prostate cancer patients.  相似文献   
92.
J E Coe  J D Feldman 《Immunology》1966,10(2):127-136
In outbred guinea-pigs with a low level of hypersensitivity to hen egg albumin (HEA) at a time when circulating antibody was not detectable, unaggregated HEA in extracutaneous tissues was rapidly lost from the injection site and did not elicit lesions of delayed hypersensitivity. Aggregated HEA, however, was retained at the depot site and produced lesions in the bladders of similarly prepared guinea-pigs. In Hartley guinea-pigs with a high level of hypersensitivity, as measured by skin reactions, unaggregated HEA, though rapidly dissipated from depot sites, elicited lesions in the bladder. Aggregated HEA, though retained at injection sites, did not produced reactions of delayed hypersensitivity in kidney, testis and muscle. The inflammation of delayed hypersensitivity did not influence the disappearance rate of labelled HEA from the lesion, while the inflammation of an Arthus response was associated with retention of labelled antigen at the injection site.  相似文献   
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This study compared patients with moderate-to-severe community-acquired pneumonia (CAP) requiring hospitalisation, who received initial therapy with either intravenous ceftriaxone plus intravenous azithromycin, followed by step-down to oral azithromycin (n = 135), with patients who received intravenous ceftriaxone combined with either intravenous clarithromycin or erythromycin, followed by step-down to either oral clarithromycin or erythromycin (n = 143). Clinical and bacteriological outcomes were evaluated at the end of therapy (EOT; day 12-16) or at the end of study (EOS; day 28-35). At baseline, mean APACHE II scores were 13.3 and 12.6, respectively, with >50% of patients classified as Fine Pneumonia Severity Index (PSI) category IV or V. Clinical success rates (cure or improvement) in the modified intent-to-treat (MITT) population at EOT were 84.3% in the ceftriaxone/azithromycin group and 82.7% in the ceftriaxone/clarithromycin or erythromycin group. At EOS, MITT success rates (cure only) were 81.7% and 75.0%, respectively. Equivalent success rates in the clinically evaluable population were 83% and 87%, respectively, at EOT, and 79% and 78%, respectively, at EOS. MITT bacteriological eradication rates were 73.2% and 67.4%, respectively, at EOT, and 68.3% vs. 60.9%, respectively, at EOS. Mean length of hospital stay (LOS) was 10.7 and 12.6 days, and the mean duration of therapy was 9.5 and 10.5 days, respectively. The incidence of infusion-related adverse events was 16.3% and 25.2% (p 0.04), respectively. An intravenous-to-oral regimen of ceftriaxone/azithromycin was at least equivalent in efficacy and safety to the comparator regimen and appeared to be a suitable treatment option for hospitalised patients with CAP.  相似文献   
98.
To investigate possible cellular mechanisms for how activation of protein kinase C inhibits the relaxation caused by isoproterenol, we studied the effect of the protein kinase C activator 4 beta-phorbol-12 beta-myristate-13 alpha-acetate (PMA) on the increase in cyclic AMP (cAMP) production and adenylate cyclase activity caused by isoproterenol in bovine pulmonary artery endothelial cells. Treatment of intact cells with PMA prevented in a time- and dose-dependent manner the increase in cAMP production caused by isoproterenol, whereas 4 alpha-phorbol-12 beta-myristate-13 alpha-acetate (4 alpha-PMA), which does not activate protein kinase C, did not affect isoproterenol-induced cAMP production. PMA also reduced the increase in adenylate cyclase activity caused by isoproterenol, forskolin, and Gpp(NH)p. To test the hypothesis that the inhibitory effect of PMA is mediated via a pertussis toxin-sensitive G protein, we determined whether pretreatment of the cells with pertussis toxin would prevent the inhibitory effects of PMA. In pulmonary endothelial cells, pertussis toxin ADP-ribosylated an Mr 40,000 peptide that comigrated with the pertussis toxin substrate of human erythrocytes. Pertussis toxin treatment eliminated the inhibitory effect of PMA on isoproterenol-stimulated cAMP production and adenylate cyclase activity. Thus, the protein kinase C activator PMA inhibits the increase in cAMP production and adenylate cyclase caused by isoproterenol. This inhibitory effect in endothelial cells appears to be mediated via a pertussis toxin-sensitive protein.  相似文献   
99.
Increased antiphospholipid antibody prevalence has been demonstrated by a number of recent studies in in-vitro fertilization (IVF) patients but the potential effects of antiphospholipid antibodies on the different components of the reproductive process and the consideration of whether to test IVF patients for antiphospholipid antibodies are controversial. The present study was undertaken to investigate the possible association between the presence of circulating antiphospholipid antibodies (namely the lupus anticoagulant and anticardiolipin antibodies), among a series of 21 consecutive IVF patients having a clinical spontaneous abortion after their first embryo transfer. As a control group (n=42), the nearest IVF cycle resulting in an ongoing pregnancy before and after each miscarried IVF cycle (i.e. the closest cycles in temporal relationship to the index cycle) was used. One patient (4.8%) in the study group and two women (4.8%) among controls were seropositive for antiphospholipid antibodies. These low and similar seropositivity rates found in the two groups studied lead us to conclude that antiphospholipid antibodies testing in IVF patients should be considered only in those women having repeated failures of implantation/clinical abortion after embryo transfer but not in an infertile general population reaching an IVF programme.   相似文献   
100.
This investigation explored the relationship of socioeconomic status (SES) to physical and mental health in two nationally representative samples of whites and African-Americans. We examined the interrelations among SES variables and assessed their contribution to health for the two racial groups. Throughout, we assessed the contribution of a less traditional indicator of SES-wealth-in the SES-health relationship. As we expected, African-Americans had lower levels of education, household income, and wealth than whites. Unexpectedly, however, the strength of the interrelationships among the three SES indicators did not differ for African-Americans and whites. In addition, we found that SES operated to affect health in a very similar fashion for African-Americans and whites. We found that wealth, in addition to more traditional indicators of SES (education and household income), made a unique and significant contribution to explaining both physical and mental health. Examining relations of different SES indicators to health across groups is critical to eliminating persistent social inequalities in health.  相似文献   
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