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151.
Thienothiadiazole‐bisthiophene (TTDT2) and diketopyrrolo–pyrrole–bisthiophene (DPPT2) are successfully electro‐copolymerized with terthiophene (T3) as an initiator and linker at low oxidative potentials. AC impedance analysis, absorption spectroscopy, and elemental composition via SEM‐EDX support the formation of donor–acceptor (D–A) type alternating block copolymers, poly(T3‐TTDT2), and poly(T3‐DPPT2). Unique optical properties that span into the near infrared‐II(>1000 nm) region and inherent electrical conductivity at the p‐type regime, n‐type regime, and in between the two regimes (i.e., typical insulator region) are observed. This study showcases the advantages of electro‐polymerization toward tailoring of next generation opto‐electronic materials.  相似文献   
152.
Poly(vinyl pyridine) has widely been used as a pH‐responsive polymer to trigger changes in self‐assembly of block copolymer micelles. However, the polymer is known to display toxic features, which limits its ultimate applicability for biological applications. Here, poly(4‐vinyl imidazole) (P4VIm), a much more biocompatible polymer, is used as a pH‐responsive block to modulate the self‐assembly of ABC triblock terpolymers. In this article, the synthesis of the poly(1‐acryloyl fructopyranose)‐block‐ poly(n‐butyl acrylate)‐block‐ poly(4‐vinyl imidazole) (PFruA52‐b‐PBuA300‐b‐P4VIm250) triblock terpolymers is first discussed by sequential reversible addition fragmentation chain transfer (RAFT) polymerization. Subsequently, the structure formation of the triblock terpolymer is elucidated by step‐wise solvent exchange. The polymer readily dissolves in methanol, but self‐assembles into micelles with PBuA cores and mixed shell in methanol–water mixtures. Solvent exchange against buffer solutions of pH 6–6.5 leads to collapse of P4VIm due to deprotonation and induces self‐assembly into caterpillar‐like non‐spherical nanoparticles, most likely via the formation of intermediate Janus particles. The rearrangement into larger hierarchical structure, as seen by small angle X‐ray scattering (SAXS), is found to process within several hours. The article is concluded by demonstrating lower cytotoxicity values for the present polymer in comparison to a structurally analogous triblock terpolymer based on poly(vinyl pyridine).  相似文献   
153.
154.
A new benzodiazepine pharmacology.   总被引:12,自引:0,他引:12  
Classical benzodiazepine drugs are in wide clinical use as anxiolytics, hypnotics, anticonvulsants, and muscle relaxants. They act by enhancing the gamma-aminobutyric acid(A) (GABA(A)) receptor function in the central nervous system. The pharmacological relevance of the multitude of structurally diverse GABA(A) receptor subtypes has only recently been identified. Based on an in vivo point mutation strategy, alpha(1)-GABA(A) receptors were found to mediate sedation, anterograde amnesia, and part of the seizure protection, whereas alpha(2)-GABA(A) receptors, but not alpha(3)-receptors, mediate anxiolysis. Rational drug targeting to specific receptor subtypes has now become possible. Only restricted neuronal networks will be modulated by the new subtype-selective drugs. Promising new anxiolytics have already been developed. A new pharmacology of the benzodiazepine site is on the horizon.  相似文献   
155.
An elderly man with decreased kidney function was admitted to hospital with gastrointestinal bleeding. After remaining stable for 2 days in hospital, he became haemodynamically unstable and an adverse effect of dabigatran was suspected, but efforts to treat the patient failed and the following morning he passed away. In conjunction with the autopsy, blood samples from his hospital stay were analysed for dabigatran, revealing the highest concentration (6400 ng/mL) apparently reported to date. Supra‐therapeutic dosing was, however, never suspected. Dabigatran is largely excreted through the kidneys. A possible cause of the high dabigatran concentrations could be a rapid decrease in kidney function that seemingly occurred over a period of 2 months, sometime between his initiation of treatment (eGFR 51–55 mL/min/1.73 m2) and subsequent hospital admission (eGFR 31 mL/min/1.73 m2). The increasing dabigatran concentrations in the patient was, however, not apparent to the prescribing doctor, as therapeutic drug monitoring of dabigatran is not recommended in current guidelines and no such analyses were performed. There may be a need to evaluate blood concentrations of dabigatran, in the light of the reported differences in interindividual concentrations, along with the increased risks of thromboembolic events with lower concentrations and major bleeding events with higher concentrations. Functional assays to assess concentrations of dabigatran in blood have been developed and are available in some hospitals to be used in suspected overdoses or before emergency surgeries. Methods to determine concentrations of dabigatran specifically have also been developed and can additionally be used for therapeutic drug monitoring in an outpatient setting, especially in high‐risk individuals.  相似文献   
156.

Purpose

Living in a cold home increases the risk of dying in winter, especially in older people. However, it is unclear which individual factors predict whether older people are living in cold homes.

Methods

Thousand four hundred two men aged 74–95 years from a U.K. population–based study reported difficulties in keeping warm during winter, answering four simple “yes/no” questions. Associations between individual's characteristics and each of the four self-reported measures of cold homes were estimated using logistic regression models. Next, we investigated whether measures of cold homes predict mortality over the subsequent 2.1 years.

Results

Manual social class, difficulties making ends meet, and not being married were each associated (P < .05) with each of the four measures of cold homes (adjusted odds ratios ranged from 1.61 to 4.68). Social isolation, poor respiratory health, and grip strength were also associated with reports of cold homes. Hundred twenty-six men died; those who reported the presence of at least three measures cold homes had increased mortality (adjusted hazard ratios 2.85 [95% confidence interval, 1.11–7.30, P = .029]).

Conclusions

Older people who find it hard to keep warm in winter, and have an elevated mortality, could be identified using a self-report questionnaire.  相似文献   
157.
We find ourselves in an era of unprecedented growth in the development and use of so-called “orphan” drugs to treat rare diseases, which are poised to represent more than one-fifth of pharmaceutical expenditures by 2022. This widespread use has been facilitated by legislative and regulatory incentives in both the United States and abroad, yet US payers and health systems have not yet made a concerted effort to understand whether and how rare diseases require special considerations on their part and how to adapt traditional methods of health technology assessment and economic evaluation to accommodate these situations. In this article, we explore the general ethical dilemmas that rare diseases present, steps taken by health technology assessment bodies worldwide to define the level of rarity that would necessitate special measures and the modifications to their assessment and valuation processes needed, and the contextual components for rare-disease evaluation that lie outside of the assessment framework as a guide to US decision makers on constructing a formal and relevant process stateside.  相似文献   
158.
159.
Maternal and Child Health Journal - Objective The association between and commonality of risk factors for poor self-rated oral health (SROH) and general health (SRGH) among new mothers has not been...  相似文献   
160.
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