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11.
Summary

A study was carried out in 16 patients with moderately severe hypertension to investigate the effects of nifedipine, given alone or combined with a diuretic, on blood pressure and on renal and platelet function. After 4 weeks on placebo, patients were randomized to receive treatment for 6 weeks with either 20?mg nifedipine twice daily or 25?mg mefruside once daily on a double-blind, double-dummy basis. All patients then received treatment for a further 6 weeks with a combination of the two drugs in the same dosage as before. The results of blood pressure measurements and laboratory investigations during the three phases of the study showed that significantly better blood pressure control was achieved with nifedipine alone than with mefruside alone. Mefruside had an additional hypotensive effect when added to nifedipine. There was no significant change in the renal blood flow or glomerular filtration rate, with a satisfactory control of blood pressure. There was also no detectable change in platelet aggregation with increasing concentrations of ADP and ristocetin. An adaptive mechanism could be responsible for the apparent lack of change compared with single dose studies.  相似文献   
12.
Antibiotic stewardship is universally agreed to be desirable, but optimal models for stewardship remain uncertain. UK stewardship targets the particular antibiotic families—cephalosporins and fluoroquinolones—blamed for the selection of Clostridium-difficile-associated disease. To balance this there have been dramatic increases in the use of penicillin–β-lactamase inhibitor combinations. By channelling selection pressure in this way, we hazard destroying the utility of these antibiotic classes in turn, as happened with gonorrhoea where penicillins, fluoroquinolones and cefixime were sequentially lost as therapies. Strikingly, in context, almost all carbapenemase-producers are highly resistant to penicillin–β-lactamase inhibitor combinations, which may select for them. There is an urgent need to explore an alternative stewardship model, seeking to limit total antibiotic use but to maintain heterogeneity in what is used, avoiding concentrated selection pressure. There is also a great need to improve and accelerate diagnostics for infection and resistance, reducing or removing the need for protracted empirical treatment with broad-spectrum agents.  相似文献   
13.
长效支气管扩张剂是稳定期慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)治疗的基石。固定剂量长效β2受体激动剂(long actingβ2 agonist,LABA)/长效抗胆碱能药物(long acting muscarinic antagonist,LAMA)复方制剂被慢性阻塞性肺疾病全球倡议推荐用于COPD的治疗。为了更深入了解已经上市的多种LABA/LAMA复方制剂如维兰特罗/乌美溴铵、茚达特罗/格隆溴铵、福莫特罗/格隆溴铵及奥达特罗/噻拖溴铵等的疗效和安全性,本文对LABA/LAMA一些重要临床研究作一综述,旨在为COPD患者提供个体化的治疗方案。  相似文献   
14.
Objective: To highlight the issue of freely available fixed-dose combinations (FDCs) of antimicrobials. Methods: A critique of two such antimicrobial FDCs was undertaken wherein the following aspects were assessed - rational and regulatory issues and justification for clinical use. Available in vitro, in vivo (animals and humans) evidence from published literature was analysed. Conclusions: There are several inadequately addressed aspects of the considered FDCs which are available in Indian market. In view of the growing problem of antimicrobial resistance, this issue must get the required attention.  相似文献   
15.
Background The absence of specific histological or serological markers, the gaps in understanding the aetiology and pathophysiology of rosacea, and the broad diversity in its clinical manifestations has made it difficult to reach international consensus on therapy guidelines. Objectives The main objective was to highlight the global diversity in current thinking about rosacea pathophysiology, classification and medical features, under particular consideration of the relevance of the findings to optimization of therapy. Methods The article presents findings, proposals and conclusions reached by the ROSacea International Expert group (ROSIE), comprising European and US rosacea experts. Results New findings on pathogenesis provide a rationale for the development of novel therapies. Thus, recent findings suggest a central role of the antimicrobial peptide cathelicidin and its activator kallikrein‐5 by eliciting an exacerbated response of the innate immune system. Cathelicidin/kallikrein‐5 also provide a rationale for the effect of tetracyclines and azelaic acid against rosacea. Clinically, the ROSIE group emphasized the need for a comprehensive therapy strategy – the triad of rosacea care – that integrates patient education including psychological and social aspects, skin care with dermo‐cosmetics as well as drug‐ and physical therapies. Classification of rosacea into stages or subgroups, with or without progression, remained controversial. However, the ROSIE group proposed that therapy decision making should be in accordance with a treatment algorithm based on the signs and symptoms of rosacea rather than on a prior classification. Conclusion The ROSIE group reviewed rosacea pathophysiology and medical features and the impact on patients and treatment options. The group suggested a rational, evidence‐based approach to treatment for the various symptoms of the condition. In daily practice this approach might be more easily handled than prior subtype classification, in particular since patients often may show clinical features of more than one subtype at the same time.  相似文献   
16.
Fixed dose combination (FDC) dual bronchodilators that co-administer a long acting β2-adrenoceptor agonist (LABA) and a long acting muscarinic antagonist (LAMA) are a new class of inhaled treatment for chronic obstructive pulmonary disease (COPD). This review focuses on the clinical evidence for the benefit of LABA/LAMA FDCs compared with monocomponent treatments, and also compared with active comparators that are widely used for the treatment of COPD, namely tiotropium and salmeterol-fluticasone. Novel FDC dual bronchodilators include QVA149 and umeclidinium/vilanterol (UMEC/VI). Long term clinical trials show that QVA149 and UMEC/VI are superior to monocomponent therapy in terms of trough forced expiratory volume in 1 s (FEV1), although the FEV1 improvement was limited to approximately 80–90% of the added monocomponent values. This suggests that the effect of combining a LABA and a LAMA is not fully additive. LABA/LAMA FDC were associated with the largest mean changes in symptoms and health status that were above the minimal clinically important difference, in contrast to the monocomponents. Furthermore, these LABA/LAMA FDCs demonstrated superiority over the active comparators tiotropium and salmeterol-fluticasone in terms of trough FEV1 and patient-reported outcomes. LABA/LAMA FDCs offer a simplified means of maximizing bronchodilation for COPD patients, with the improvements in lung function being mirrored by benefits in terms of symptoms and exacerbations. The use of LABA/LAMA FDCs in clinical practice is set to grow and further studies are needed to define their optimal place in treatment guidelines.  相似文献   
17.
In this study calendering is used as a downstream technique to shape monolithic co-extruded fixed-dose combination products in a continuous way. Co-extrudates with a metoprolol tartrate-loaded sustained-release core and a hydrochlorothiazide-loaded immediate-release coat were produced and immediately shaped into a monolithic drug delivery system via calendering, using chilled rolls with tablet-shaped cavities. In vitro metoprolol tartrate release from the ethylcellulose core of the calendered tablets was prolonged in comparison with the sustained release of a multiparticulate dosage form, prepared manually by cutting co-extrudates into mini-matrices. Analysis of the dosage forms using X-ray micro-computed tomography only detected small differences between the pore structure of the core of the calendered tablet and the mini-matrices. Diffusion path length was shown to be the main mechanism behind the release kinetics. Terahertz pulsed imaging visualized that adhesion between the core and coat of the calendered tablet was not complete and a gradient in coat thickness (varying from 200 to 600 μm) was observed. Modulated differential scanning calorimetry and X-ray diffraction indicated that the solid-state properties of both drugs were not affected by the calendering procedure.  相似文献   
18.

Background:

Decreases in the bioavailability of rifampicin (RFP) can lead to the development of drug resistance and treatment failure. Therefore, we investigated the relative bioavailability of RFP from one four-drug fixed-dose combination (FDC; formulation A) and three two-drug FDCs (formulations B, C, and D) used in China, compared with RFP in free combinations of these drugs (reference), in healthy volunteers.

Methods:

Eighteen and twenty healthy Chinese male volunteers participated in two open-label, randomized two-period crossover (formulations A and C) or one three-period crossover (formulations B and D) study, respectively. The washout period between treatments was 7 days. Bioequivalence was assessed based on 90% confidence intervals, according to two one-sided t-tests. All analyses were done with DAS 3.1.5 (Mathematical Pharmacology Professional Committee of China, Shanghai, China).

Results:

Mean pharmacokinetic parameter values of RFP obtained for formulations A, B, C, and D products were 11.42 ± 3.41 μg/ml, 7.86 ± 5.78 μg/ml, 13.05 ± 6.80 μg/ml, and 16.18 ± 3.87 μg/ml, respectively, for peak plasma concentration (Cmax), 91.43 ± 30.82 μg·h−1 ·ml−1, 55.49 ± 37.58 μg·h−1 ·ml−1, 96.50 ± 47.24 μg·h−1 ·ml−1, 101.47 ± 33.07 μg·h−1 ·ml−1, respectively, for area under the concentration-time curve (AUC0−24 h).

Conclusions:

Although the concentrations of RFP for formulations A, C, and D were within the reported acceptable therapeutic range, only formulation A was bioequivalent to the reference product. The three two-drug FDCs (formulations B, C and D) displayed inferior RFP bioavailability compared with the reference (Chinese Clinical Trials registration number: ChiCTR-TTRCC-12002451).  相似文献   
19.
BackgroundEffective and safe drug therapy for the management of acute postoperative pain has relied on orally administered analgesics such as ibuprofen, naproxen and acetaminophen, or N-acetyl-p-aminophenol (APAP), as well as combination formulations containing opioids such as hydrocodone with APAP. The combination of ibuprofen and APAP has been advocated in the last few years as an alternative therapy for postoperative pain management. The authors conducted a critical analysis to evaluate the scientific evidence for using the ibuprofen-APAP combination and propose clinical treatment recommendations for its use in managing acute postoperative pain in dentistry.Types of Studies ReviewedThe authors used quantitative evidence-based reviews published by the Cochrane Collaboration to determine the relative analgesic efficacy and safety of combining ibuprofen and APAP. They found additional articles by searching the Ovid MEDLINE, PubMed and http://ClinicalTrials.gov databases.ConclusionsThe results of the quantitative systematic reviews indicated that the ibuprofen-APAP combination may be a more effective analgesic, with fewer untoward effects, than are many of the currently available opioid-containing formulations. In addition, the authors found several randomized controlled trials that also indicated that the ibuprofen-APAP combination provided greater pain relief than did ibuprofen or APAP alone after third-molar extractions. The adverse effects associated with the combination were similar to those of the individual component drugs.Practical ImplicationsCombining ibuprofen with APAP provides dentists with an additional therapeutic strategy for managing acute postoperative dental pain. This combination has been reported to provide greater analgesia without significantly increasing the adverse effects that often are associated with opioid-containing analgesic combinations. When making stepwise recommendations for the management of acute postoperative dental pain, dentists should consider including ibuprofen-APAP combination therapy.  相似文献   
20.
目的探讨不同药物的联合降压治疗方案对高血压患者血压和脉搏波传导速度(PWV)的影响。方法选择2008年1~9月在北京医院心内科门诊就诊的高血压患者66例,其中男性36例,女性30例,年龄50~75岁,平均(60.7±7.5)岁。将研究对象随机分为两组:一组患者采用氨氯地平+复方阿米洛利(A组)治疗,另一组患者采用氨氯地平+替米沙坦(B组)治疗。观察不同的联合降压方案对血压、心率、肱踝动脉PWV(baPWV)、血脂、血糖、肌酐和尿酸的影响。结果两种治疗方案均有良好的降压作用,A组平均收缩压和舒张压由(154.4±12.7)mm Hg和(89.1±7.4)mm Hg分别降至(127.7±11.2)mm Hg和(74.8±8.8)mm Hg(均为P<0.01);B组平均收缩压和舒张压由(155.0±12.9)mm Hg和(90.9±10.1)mm Hg分别降至(128.6±9.9)mm Hg和(77.7±9.0)mm Hg(均为P<0.01)。治疗前和治疗后及两组之间比较,治疗方案对baPWV、心率、血脂、血糖和肌酐无明显影响。B组治疗后尿酸水平由治疗前的(335.8±58.5)μmol/L上升到(361.4±51.3)μmol/L(P=0.017)。结论两种联合治疗方案均有良好的降压作用,对baPWV均无显著影响。  相似文献   
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