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51.
Summary— Experiments were designed to determine whether or not indapamide, an antihypertensive agent with vasodilator properties, inhibits endothelium-dependent contractions. Rings of aortae with and without endothelium from spontaneously hypertensive rats (SHR) were suspended in conventional organ chambers for the measurement of isometric force. Acetylcholine and adenosine diphosphate-β-S in the presence of a nitric oxide synthase inhibitor, caused endothelium-dependent contractions, which were inhibited by indapamide. The compound (10−4M) also slightly reduced the contractions of rings without endothelium evoked by U-46,619, which activates thromboxane-endoperoxide receptors. These results demonstrate that indapamide inhibits endothelium-dependent contractions in the SHR aorta, and suggest that the inhibition is due, at least in part, to the action of the drug on the hypertensive vascular smooth muscle.  相似文献   
52.
Latent inhibition (LI) of a conditioned emotional response (CER) has been proposed as a quantitative measure of selective attention. We have assessed the parallels of the pharmacology of LI in rats with the clinical pharmacology of schizophrenia. Drug and vehicle treated rats were divided into groups and preexposed 20 times to cage illumination as a CS, or not preexposed. All groups were conditioned with 2 CS-footshock pairings. The following day CER, as measured by interruption of drinking in response to CS presentation, was recorded. LI was observed as a decreased CER in preexposed relative to non-preexposed animals. LI was enhanced by haloperidol 0.3 mg/kg after 7 or 14 daily treatments, but not after a single acute dose. Haloperidol doses of 0.3 and 0.03 mg/kg enhanced LI, while doses of 0.003 and 3.0 mg/kg had no effect. Haloperidol enhancement of LI was unaffected by the coadministration of the anticholinergic agent trihexyphenidyl. Enhancement of LI is exhibited by the antipsychotic drugs fluphenazine, chlorpromazine, thiothixene, thioridazine, mesoridazine, and metoclopramide but not clozapine. The non-antipsychotic drugs pentobarbital, imipramine, chlordiazepoxide, trihexyphenidyl, and promethazine failed to enhance LI. LI exhibits striking parallels to the clinical pharmacology of schizophrenia.Preliminary data were presented in part at the Society for Neuroscience Annual Meeting, Phoenix, AZ, 1989  相似文献   
53.

Background  

Decision aids (DA) to assist patients in evaluating treatment options and sharing in decision making have proliferated in recent years. Most require high literacy and do not use plain language principles. We describe one of the first attempts to design a decision aid using principles from reading research and document design. The plain language DA prototype addressed treatment decisions for localized prostate cancer. Evaluation assessed impact on knowledge, decisions, and discussions with doctors in men newly diagnosed with prostate cancer.  相似文献   
54.
Potent inhibition of HIV-1 entry by (s4dU)35   总被引:2,自引:0,他引:2  
  相似文献   
55.
There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.   相似文献   
56.
57.
BACKGROUND: The pelvic floor muscles are active in normal erectile function. Therefore, it was hypothesised that weak pelvic floor muscles could be a cause of erectile dysfunction.AIMS: To compare the efficacy of pelvic floor muscle exercises and manometric biofeedback with lifestyle changes for men with erectile dysfunction.Design of study: Randomised controlled trial.SETTING: The Somerset Nuffield Hospital, Taunton, United Kingdom.METHOD: Fifty-five men with erectile dysfunction (median age 59.2 years; range 22-78 years) were enrolled from a local urology clinic. Of these, 28 participants were randomised to an intervention group and engaged in pelvic floor exercises, as well as receiving biofeedback and suggestions for lifestyle changes. Twenty-seven controls were solely advised on lifestyle changes. Baseline, 3- and 6-month assessments were: erectile function domain of International Index of Erectile Function (IIEF), Partner's International Index of Erectile Function (PIIEF), Erectile Dysfunction-Effect on Quality of Life (ED-EQoL), anal manometry, digital anal measurements, and clinical assessment by an assessor blind to treatment allocation. After 3 months, the control group were transferred to the active arm.RESULTS: At 3 months, compared with controls, men in the intervention group showed significant mean increases in the erectile function domain of the IIEF (6.74 points, P = 0.004); anal pressure (44.16 cmH(2)O, P <0.001); and digital anal grades (1.5 grades, P <0.001). All showed further improvement in these outcomes at 6 months. Similar benefits were seen in men of the control arm after transfer to active treatment. A total of 22 (40.0%) participants attained normal function, 19 (34.5%) participants had improved erectile function, and 14 (25.5%) participants failed to improve.CONCLUSION: Pelvic floor muscle exercises and biofeedback are an effective treatment for men with erectile dysfunction.  相似文献   
58.
The amino acid sequence of the N-methyl-D-aspartate (NMDA) receptor subunit NR2B from the brown ghost knife fish Apteronotus leptorhynchus has been determined and compared with the sequence of the murine NR2B. This comparison revealed high levels of sequence conservation throughout the ligand binding and membrane spanning segments. The functional properties of the NR1 and NR2B receptor complex were examined by coexpression in HEK cells. The recombinant AptNR1/NR2B receptors produced robust currents after stimulation with glutamate or NMDA in the presence of glycine. Measurements of the concentration dependencies for these agonists indicated that the agonist binding sites on the apteronotid receptor are highly conserved, with nearly identical agonist affinities to those of the murine NR1/NR2B receptor. The kinetic responses of the fish receptor were also highly conserved, with deactivation rates for the AptNR2B receptor matching those of the murine NR2B containing receptor. Evidently, most of the unique functional properties that reside in the NR2B receptor subunit have been well conserved in teleost NMDA receptors. On the other hand, the apteronitid receptor displayed a lowered sensitivity to voltage-dependent Mg(2+) block and a reduced affinity for the NR2B-specific noncompetitive antagonist ifenprodil. We conclude that the functional properties that result from the incorporation of the NR2B receptor in the NMDA receptor complex have been maintained since the evolutionary divergence of teleost and mammalian organisms.  相似文献   
59.
Among more than 200 human papillomavirus (HPV) types presumed to exist, 18 "high-risk" HPV types are frequently found in anogenital cancer. The best studied types are HPV-16 and 18, which are only distantly related to one another and form two separate phylogenetic branches, each including six closely related types. HPV-30, 53, 56, and 66 form a third phylogenetic branch unrelated to HPV-16 and 18. Worldwide comparison of HPV-16 and 18 isolates revealed a distribution of variant genomes that correlated with the geographic origin and the ethnicity of the infected cohort and led to the concept of unique African, European, Asian, and Native American HPV-16 and 18 variants. Here, we address the question whether similar phylogenies are found for HPV-53, 56, and 66 by determining the sequence of the long control regions (LCR) of these HPVs in samples from Europe, Asia, and Africa, and from immigrant societies in North and South America. Phylogenetic trees calculated from point mutations and a few insertions/deletions affecting 2-4.2% of the nucleotide sequences were distinct for each of the three HPVs and divergent from HPV-16 and 18. In contrast to the "star-phylogenies" formed by HPV-16 and 18 variants, 44 HPV-53 isolates represented nine variants, which formed two deep dichotomic branches reminiscent of the beginning split into two new taxa, as recently observed for subtypes of HPV-44 and 68. A total of 66 HPV-56 isolates represented 17 variants, which formed three branches preferentially containing European, Asian, and African variants. Variants of a fourth branch, deeply separated from the other three, were characterized by a 25 bp insertion and created a dichotomy rather than star-like phylogeny. As it contained isolates from cohorts in all continents, it may have evolved before the spread of humans into all continents. 18 of 31 HPV-66 isolates represented the prototype clone, which was found in all parts of the world, while the remaining 13 clones formed 11 branches without any geographic association. Our findings confirm the notion of a quantitatively limited genomic diversity of each HPV type with some correlation to the geographic origin of the sample. In addition, we observed in some variants of these three HPV types mutations that affect the amino acid sequence of the E6 oncoproteins and the L1 capsid protein, supporting the possibility of immunogenic and oncogenic diversity between variants of any HPV type.  相似文献   
60.
We compared the cytomegalovirus (CMV) antigenemia assay with shell vial cultures of polymorphonuclear leukocyte (PMNL)-enriched blood fractions for rapid diagnosis of CMV viremia. PMNL fractions of 280 blood specimens from 171 patients (170 solid-organ transplant recipients and 1 patient undergoing pretransplant evaluation) were inoculated in shell vial and conventional CMV cultures. A commercially available kit (CMV-vue kit; INCSTAR Corp.) was used for the CMV antigenemia assay, in which PMNL preparations were stained with monoclonal antibodies directed against the CMV protein pp65. Mixed-leukocyte blood fractions from the same blood specimens were inoculated in parallel shell vial and conventional cultures. CMV viremia (defined by the isolation of CMV in conventional cultures) was detected in 32 (13%) of 245 PMNL fractions included in the final analysis. Twenty-eight (87.5%) were also positive in the CMV antigenemia assay, whereas 22 (69%) were positive in shell vial cultures. Ten (4%) additional PMNL fractions positive only in the CMV antigenemia assay were from eight patients with active CMV infections (six patients), who had previous or subsequent episodes of CMV viremia (seven patients), or in whom CMV was isolated in cultures of simultaneously obtained mixed-leukocyte fractions (three patients). Overall, the CMV antigenemia assay was significantly more sensitive than shell vial cultures for detection of CMV in the PMNL fraction of blood leukocytes (P < 0.01, McNemar's test), and we recommend it as the method of choice for rapid diagnosis of CMV viremia.  相似文献   
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