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31.
A series of new pyrazoline compounds bearing a pyridyl moiety (4ai) were synthesized by condensing appropriate chalcones with hydrazine hydrate and tested for antimicrobial and antioxidant activities. According to in vitro antimicrobial activity against Bacillus subtilis, Staphylococcus epidermidis, Proteus vulgaris, Pseudomonas aeruginosa, Aspergillus niger and Penicillium chrysogenum and antioxidant activity by DPPH method, the compounds 4a, 4d, 4i and 4e, 4f, 4h showed maximum antimicrobial and antioxidant activities, respectively. Physiochemical properties and Lipinski’s ‘Rule of Five’ analysis predicted higher intrinsic quality of the synthesized compounds and revealed that these compounds have good bioavailability and druglikeness properties.  相似文献   
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Rates of relapse in BD are high with medication nonadherence identified as an important contributor to relapse. Psychopharmacology remains a key component to the treatment of BD; therefore, increased understanding of medication use and ways to promote greater adherence is essential. The aim of the study was to identify how participants with BD experience taking prescribed medication. Participants had BD I or BD II, were users of specialist mental health services, aged 18–64 years, euthymic, mildly hypomanic or depressed, and on any combination of medication. Exclusion criteria were minimal. A semistructured interview was completed exploring patients’ views of BD and factors influencing adherence based on the Subjective Experience of Medication Interview. An inductive thematic analysis was used to identify themes. The study participants (n = 36) had predominantly bipolar I (78%) and were female (69%), and of New Zealand European ethnicity (67%) with 14% Maori. The mean age was 41 years (SD: 12.0). Findings from the thematic analysis generated three themes: Learning about the clinical meaning of having BD, Understanding how to use medication, and Understanding what works for me. The qualitative nature of our study limits the generalizability of our findings to a broader population of individuals with BD. The participants developed confidence in being in charge of their BD through a process of learning about BD and medication and understanding what this meant for them. The findings support greater emphasis on collaborative approaches that recognize the expertise of the individual with BD and the clinician.  相似文献   
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Disruption of spermatogenesis found in azoospermia and oligozoospermia is thought to be of primarily genetic origin. Sl/Sl(d) mutant mice offer a model system in which lack of transmembrane type c-kit ligand (KL2) expression on the somatic Sertoli cell surface results in disruption of spermatogenesis. We investigated the ability of adeno-, adeno-associated-, retro-, and lentiviral vectors to transduce Sertoli cells and found that transduction with either adeno- or lentiviral vectors led to reporter gene expression for more than 2 mo after testicular tubule injection. Because adenoviral vectors showed toxicity, lentiviral vectors were used to express the c-kit ligand in Sl/Sl(d) Sertoli cells. Restoration of spermatogenesis was observed in all recipient testes. Furthermore, the sperm collected from recipient testes were able to generate normal pups after intracytoplasmic sperm injection. None of the offspring carried the transgene, suggesting the inability of lentiviral vectors to infect spermatogenic cells in vivo. We propose that lentiviral vectors can be used for gene therapy of male infertility without the risk of germ-line transmission.  相似文献   
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OBJECTIVES: A subgroup analysis of the Valsartan Heart Failure Trial (Val-HeFT) was performed to evaluate the effects of the angiotensin II receptor blocker, valsartan, in the patients with chronic heart failure (HF) not receiving angiotensin-converting enzyme (ACE) inhibitors. BACKGROUND: The ACE inhibitors reduce mortality and morbidity in patients with HF. Nonetheless, nearly 20% of potentially eligible patients may not be prescribed ACE inhibitors. RESULTS: Val-HeFT was an international, randomized, double-blinded trial that compared valsartan with placebo when added to the prescribed treatment of patients with HF. The two primary end points of the study were all-cause mortality and the composite of all-cause mortality and morbidity (sudden death with resuscitation, hospital admission for HF, or administration of intravenous inotropic or vasodilator drugs for >or=4 h without hospital admission). Of the 5,010 patients enrolled in the trial, 366 (7.3%) were not treated with ACE inhibitors at baseline. The effects of valsartan on the primary and secondary end points of the study were assessed in this subgroup of patients. RESULTS: Both all-cause mortality and combined mortality and morbidity for patients not treated with ACE inhibitors were significantly reduced in the valsartan treatment group compared with the placebo group (17.3% vs. 27.1%, p = 0.017 and 24.9% vs. 42.5%, p < 0.001, respectively). Consistent with the data on clinical events, patients randomized to valsartan showed improvements in physiologic variables, such as ejection fraction, left ventricular internal diameter in diastole, and plasma neurohormone levels. Permanent discontinuation of study treatment because of adverse experiences was comparable between the two groups. CONCLUSIONS: Val-HeFT has provided the first placebo-controlled outcome data demonstrating a favorable effect of an angiotensin receptor blocker on mortality and morbidity in patients with HF not treated with ACE inhibitors. Based on these results, valsartan appears to be an effective therapy in ACE inhibitor-intolerant patients.  相似文献   
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Objective Optimal diagnostic criteria for the 4‐mg intravenous dexamethasone suppression test (IVDST) in patients with Cushing’s syndrome (CS), compared with normal subjects, have not been established. We evaluated the performance of the 4‐mg IVDST for differentiating CS from normal subjects and to define the responses in CS of various aetiologies. Design, subjects, measurements Thirty‐two control subjects [normal and overweight/obese participants with or without type 2 diabetes) were prospectively studied, and data from 66 patients with Cushing’s disease (CD), three with ectopic ACTH syndrome (EAS), 14 with adrenal Cushing’s (AC)] and 15 with low probability of CS (LPC) from three tertiary hospitals were retrospectively evaluated. Dexamethasone was infused at 1 mg/h for 4 h. Plasma cortisol and ACTH were measured at ?60 min (baseline), ?5 min, +3 h, +4 h, +5 h and at +23 and +23·5 h on Day 2. Results Control subjects (including those with type 2 diabetes) exhibited a marked suppression of cortisol which was maintained until Day 2. Two of 15 patients with LPC had Day 2 cortisol results that overlapped with CS. Patients with CD demonstrated partial suppression, with rebound hypercortisolism on Day 2. Patients with AC and EAS did not suppress cortisol levels. Day 2 cortisol level of >130 nmol/l (or >20% of the baseline) diagnosed CS with 100% sensitivity and 96% specificity. Conclusion While the IVDST allowed complete discrimination between control subjects and CS, 13% of LPC overlapped with CS. Given the small number of EAS, no conclusion can be drawn regarding the utility of this test in the differential diagnosis of CS.  相似文献   
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An “intellectual connection” approach to design a facile and new synthesis of suitably substituted 2-aminoimidazole-based precursors of expected antiasthmatic agents through a benzidine type of rearrangement of 2-phenylazoimidazole and subsequent coupling of the product thus obtained with alkylisothiocyanates involving a degenerative operation, thereby improving the time frame of the overall synthetic sequence, is reported. The alkylisothiocyanates required in this synthetic sequence are prepared using a best combination of reported methods. The compounds reported here can be used to produce derivatives of other biological agents.  相似文献   
40.
Surrogate end points in heart failure   总被引:5,自引:0,他引:5  
Because of the increasing number of pharmacologic strategies available for treatment of heart failure (HF), the time has come to reassess the adequacy of end points used to evaluate therapeutic efficacy. Interest in the use of surrogate end points in clinical studies is increasing. A surrogate end point is defined as a measurement that can substitute for a true end point for the purpose of comparing specific interventions or treatments in a clinical trial. A true end point is one that is of clinical importance to the patient (e.g., mortality or quality of life), whereas a surrogate end point is one biologically closer to the disease process (e.g., ejection fraction or left ventricular volume in HF). The prime motivation for the use of a surrogate end point concerns the possible reduction in sample size or trial duration. Such reductions have important cost implications and in some cases may influence trial feasibility. Another, perhaps more important, aspect of measuring surrogate end points is that they increase our understanding of the mechanism of action of drugs and thus may help physicians to take a more enlightened approach in managing their patients. In this article we have analyzed the possible potentials of the surrogate end points in clinical studies of patients with chronic HF. Other uses of possible surrogates are discussed, and the limitations in finding true surrogates are mentioned. At this time we conclude there is no well established surrogate in HF.  相似文献   
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