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971.
The "Quit. For Life" campaign was a media-based programme that was aimed at reducing the prevalence of smoking in Sydney. The programme committee set four intermediate goals which it felt had to be met for such a change in prevalence to occur. From households selected at random in Sydney and Melbourne, 5713 people were interviewed to assess whether the campaign attained these goals. The television commercials that were designed for the campaign, their frequency and the timing of their screening produced a higher recall of the commercial's message and the use of campaign back-up services than were specified originally in the goals. During the campaign there was a progressive increase in the number of smokers in Sydney who reported that they were likely to quit; this was significantly different from Melbourne data by the end of the campaign and thus fulfilled another campaign goal. However, shortly after the campaign ended, the proportion of smokers who intended to quit smoking was the same in the two cities. A cohort study of 949 people from the baseline study showed that, during the 12-month period of follow-up, 66% of Sydney smokers tried to stop or to reduce their smoking. In the control city, Melbourne, 60% of smokers reported making such attempts. Of the original smokers, 23% in Sydney and 9% in Melbourne quit during the follow-up period--a statistically significant difference. As well, 10% of the original ex-smokers in Sydney and 11% in Melbourne relapsed, while 4% of nonsmokers in both cities began smoking by the end of the second survey.  相似文献   
972.
Personal view:     
The author, a consultant physician at City Hospital, Edinburgh, proposes a series of public health measures to control the transmission of the AIDS-associated HTLV-III virus among intravenous drug abusers. He supports screening of blood without consent, tracing and screening the sexual contacts of HTLV-III positive individuals, counseling of the patients and their contacts, arranging access to unshared needles and syringes for persistent drug abusers, and notification of the general practitioners of hospital patients found to be HTLV-III positive. Welsby contends that his proposals do not violate the Department of Health and Social Security's code on confidentiality of health data and that several of his suggested actions are already in use against other, less menacing, sexually-transmitted diseases.  相似文献   
973.
974.
Fifty-two patients with metastatic or recurrent non-small-cell lung cancer (NSCLC) were treated, during a phase II trial, with methylglyoxal-bis-(guanylhydrazone) (MGBG). Of the 44 patients who had adequate trials, 4 had partial responses (PR), for an overall 9% PR rate. Response durations ranged from 3 to 5+ months. Prior treatment with chemotherapy may have adversely affected response rate; 15% of previously untreated patients responded, compared to only 4% of previously treated patients. A syndrome of weakness and fatigue was the most serious side effect. Anorexia and weight loss, stomatitis, nausea and vomiting, diarrhea, and peripheral neuropathy were the other toxic effects. We conclude that MGBG has activity in NSCLC, especially in previously untreated patients, and further studies are indicated in that population.  相似文献   
975.
Consent forms for cataract surgery performed at Burnley General Hospital (BGH) and Blackburn Royal Infirmary (BRI) from October 4 to December 7, 2004, were prospectively reviewed to ensure that the East Lancashire Hospital's National Health Service (NHS) Trust Policy on consent to treatment and Department of Health (DoH) guidelines were being followed when seeking consent for cataract surgery. A set of 22 criteria derived as standards were formulated from the reference guide published by the DoH and from the East Lancashire trust policy document for consent to treatment. Each consent form was measured against these standards. Cases were randomly selected between BRI and BGH prospectively. All consent forms completed by physicians involved in formulating the standards were excluded. The review showed the NHS Trust Policy and DoH guidelines were largely followed when seeking consent for cataract surgery. However, certain areas were found to be deficient. If a health professional fails to obtain proper consent and the patient suffers harm as a result of treatment, it may be a factor in a claim of negligence against that health professional. Subsequent recommendations may include simple solutions that can be implemented to improve clinical practice when obtaining informed consent.  相似文献   
976.
The erectile dysfunction medicine sildenafil citrate (Viagra) inhibits phosphodiesterase type 6 (PDE6), an essential enzyme involved in the activation and modulation of the phototransduction cascade. Although Viagra might thus be expected to impair visual performance, reports of deficits following its ingestion have so far been largely inconclusive or anecdotal. Here, we adopt tests sensitive to the slowing of the visual response likely to result from the inhibition of PDE6. We measured temporal acuity (critical fusion frequency) and modulation sensitivity in four subjects before and after the ingestion of a 100-mg dose of Viagra under conditions chosen to isolate the responses of either their short-wavelength-sensitive (S-) cone photoreceptors or their long- and middle-wavelength-sensitive (L- and M-) cones. When vision was mediated by S-cones, all subjects exhibited some statistically significant losses in sensitivity, which varied from mild to moderate. The two individuals who showed the largest S-cone sensitivity losses also showed comparable losses when their vision was mediated by the L- and M-cones. Some of the losses appear to increase with frequency, which is broadly consistent with Viagra interfering with the ability of PDE6 to shorten the time over which the visual system integrates signals as the light level increases. However, others appear to represent a roughly frequency-independent attenuation of the visual signal, which might also be consistent with Viagra lengthening the integration time (because it has the effect of increasing the effectiveness of steady background lights), but such changes are also open to other interpretations. Even for the more affected observers, however, Viagra is unlikely to impair common visual tasks, except under conditions of reduced visibility when objects are already near visual threshold.  相似文献   
977.
As part of a fully integrated and comprehensive strategy to discover novel antibacterial agents, NMR- and mass spectrometry-based affinity selection screens were performed to identify compounds that bind to protein targets uniquely found in bacteria and encoded by genes essential for microbial viability. A biphenyl acid lead series emerged from an NMR-based screen with the Haemophilus influenzae protein HI0065, a member of a family of probable ATP-binding proteins found exclusively in eubacteria. The structure-activity relationships developed around the NMR-derived biphenyl acid lead were consistent with on-target antibacterial activity as the Staphylococcus aureus antibacterial activity of the series correlated extremely well with binding affinity to HI0065, while the correlation of binding affinity with B-cell cytotoxicity was relatively poor. Although further studies are needed to conclusively establish the mode of action of the biphenyl series, these compounds represent novel leads that can serve as the basis for the development of novel antibacterial agents that appear to work via an unprecedented mechanism of action. Overall, these results support the genomics-driven hypothesis that targeting bacterial essential gene products that are not present in eukaryotic cells can identify novel antibacterial agents.  相似文献   
978.
PAGE4 is an X chromosome-linked cancer testis antigen and is a potential new tumor-associated antigen that is overexpressed in prostate and uterine cancers. The purpose of this study was to identify a human CTL epitope and a corresponding agonist epitope of PAGE4 to determine if PAGE4 is a potential target for vaccine-mediated immunotherapy against PAGE4-expressing tumors. A class I PAGE4 epitope was identified with a high level of binding to HLA-A2. PAGE4 peptide-pulsed dendritic cells were then used to generate human PAGE4-specific T-cell lines. Further studies demonstrated the generation of an enhancer agonist epitope. Compared with the native peptide, the agonist (i) bound to HLA-A2 molecules at lower peptide concentrations, (ii) demonstrated a higher stability of the peptide HLA-A2 complex, (iii) induced higher levels of production of IFN-gamma, Granzyme B, TNF-alpha, IL-2 and lymphotactin by PAGE4-specific T-cell lines and (iv) T-cell lines generated against the agonist peptide were more efficient to lyse HLA-A2 human tumor cells expressing native PAGE4. The studies reported here are the first to describe a PAGE4 CTL epitope and its agonist epitope, and thus identify PAGE4 as a potentially useful target for vaccine-mediated therapy of prostate cancer.  相似文献   
979.
INTRODUCTION/HYPOTHESIS: Over-expression of the c-Met receptor tyrosine kinase has been described in a variety of cancers and implicated in tumor progression. Unlike some solid tumors, current evidence indicates that c-Met activation in colon cancer is unrelated to gene mutation, is ligand dependent, and occurs via a paracrine fashion. We hypothesize that over-expression of the c-Met receptor and its ligand, hepatocyte growth factor (HGF) in the tumor microenvironment is associated with tumor progression and metastases. METHODS: Primary tumor c-Met and HGF mRNA expression was analyzed in 60 colon adenocarcinomas. Receptor and ligand expression was analyzed for correlation and association with clinicopathologic features and outcome. RESULTS: Compared to adjacent normal mucosa, 69% and 48% of tumors showed a greater than 2- and greater than 10-fold elevation in c-Met mRNA, respectively. Elevated HGF mRNA was noted in 47% of tumors with 19% having a greater than 10-fold increase. Tumor c-Met expression was correlated with HGF expression, and a cohort of 33 patients could be defined with both low c-Met and HGF expression. Compared with the 27 tumors with either high c-Met or HGF, the cohort with low c-Met and HGF expression had fewer nodal and distant metastases as well as improved overall survival (HR=2.3, p<0.05). CONCLUSION: Evaluation of the c-Met receptor in context of ligand, HGF, allows identification of a metastatic phenotype that correlates with advanced stage and poor survival. c-Met and HGF co-expression in the tumor microenvironment could be useful in the molecular staging of colon cancer and viable therapeutic targets.  相似文献   
980.
Taxanes, including paclitaxel and docetaxel, are widely used cytotoxic agents for the treatment of solid tumors. Paclitaxel, a small, hydrophobic agent, binds extensively to plasma proteins, and its pharmacokinetic profile is characterized by a short plasma elimination half-life with a broad tissue distribution. These unfavorable pharmacokinetic characteristics are associated with limited tumor exposure and high systemic exposure, reducing the therapeutic index of paclitaxel. Paclitaxel poliglumex (PPX, CT-2103), a polymer-drug conjugate of paclitaxel and poly-L-glutamic acid, was designed to enhance the therapeutic index of paclitaxel by improving its pharmacokinetic profile, and to provide a water-soluble alternative to the standard paclitaxel formulation. Potential advantages of polymer-drug conjugates include delivery of a higher concentration of active drug to tumor tissue and limited exposure of normal tissues. In addition, the slow release of drug from the polymer carrier lowers peak plasma concentrations of the active drug.  相似文献   
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