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81.
The development of new drugs is accelerated by rapid access to functionalized and D-labeled molecules with improved activity and pharmacokinetic profiles. Diverse synthetic procedures often involve the usage of gaseous reagents, which can be a difficult task due to the requirement of a dedicated laboratory setup. Here, we developed a special reactor for the on-demand production of gases actively utilized in organic synthesis (C2H2, H2, C2D2, D2, and CO2) that completely eliminates the need for high-pressure equipment and allows for integrating gas generation into advanced laboratory practice. The reactor was developed by computer-aided design and manufactured using a conventional 3D printer with polypropylene and nylon filled with carbon fibers as materials. The implementation of the reactor was demonstrated in representative reactions with acetylene, such as atom-economic nucleophilic addition (conversions of 19–99%) and nickel-catalyzed S-functionalization (yields 74–99%). One of the most important advantages of the reactor is the ability to generate deuterated acetylene (C2D2) and deuterium gas (D2), which was used for highly significant, atom-economic and cost-efficient deuterium labeling of S,O-vinyl derivatives (yield 68–94%). Successful examples of their use in organic synthesis are provided to synthesize building blocks of heteroatom-functionalized and D-labeled biologically active organic molecules.  相似文献   
82.
Software Package for Modelling Transient Processes in Controlled Objects   总被引:1,自引:0,他引:1  
We consider the main stage of design for control systems, i.e., simulation of the transient process, which requires a large volume of precise computation associated with evaluating the operation of the prospective system and optimal tuning of controller parameters.  相似文献   
83.
Russian Engineering Research - The influence of technological and design factors on rotary turning by multifaceted cutters is investigated. Semiempirical formulas are proposed to determine the best...  相似文献   
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Were studied psychovegetative and somatic correlations in 115 patients with ischemic heart disease, having aortocoronary shunting operation and being at the sanatorium stage of the medical rehabilitation. To 70 patients was been carried out treatment with application of autogenous training (AT), to 45--without use of AT. The research has confirmed the presence in the patients psychological disadaptation, expressed essentially in asthenoneurotic and hypochondriac reactions. Is established, that estimation of expressiveness of emotional tension, investigated with the aid of Spilberger's psychometric scale, can be confirmed by parameters of peroxide oxidation of lipids and mathematical analysis of heart rythm. The use of variant of training modified by the authors has revealed improvement of clinical parameters, reflecting health state of the patients, which correlate with the data of the psychological test and the results of bicycle ergometry [correction of veloergometry].  相似文献   
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Radionuclide gastroscopy conducted in patients with vast purulent wounds and sepsis disclosed reduced motor-evacuatory function of the stomach and the rate of its fractional emptying, that supports the necessity of continuous administration of nutrient mixtures by a drip method. A significant improvement of the motor evacuatory function and the rate of fractionated emptying of the stomach, 9-12 days after the commencement of the enteral (tube) nutrition, has shown the necessity of its use at the early stages of the course of severe purulent infection. The investigation of the absorptive capacity of the intestine with the use of the D-xylose test has revealed that it is insignificantly decreased in 82.6% of patients with severe purulent infection, and tube nutrition in such patients could be successfully conducted. Only in 17.4% of the patients the adsorptive capacity of the intestine was significantly decreased, and in these cases predominantly parenteral nutrition was recommended.  相似文献   
89.
An analysis of the character of operations in 106 patients with traumas of the spleen has been made. Organ-preserving operations with a laser scalpel were fulfilled on 28 patients. Absolute indications for performing the organ-preserving operation were revealed in 28% of the patients. Relative indications were found in 53%. Methods of laser coagulation are proposed which helped to preserve the spleen in 46% of the patients during the last 4 years.  相似文献   
90.
SR 27417, a potent PAF receptor antagonist, inhibited in a dose-dependent manner the hypotensive effect of PAF in rats. It protected rats with an ED50 value of 6 +/- 2 micrograms/kg (n = 6), when given i.v., 1 min before PAF administration. After i.v. administration, SR 27417 exhibited extended duration of action, a significant protective effect was observed up to 48 h after the administration. After i.v. injection, SR 27417 (0.3, 1 and 3 mg/kg) afforded dose-dependent protection of actively sensitized rats against ovalbumin-induced hypotension but also totally reversed established antigen-induced hypotension. These results therefore confirm that PAF plays a major role in anaphylactic shock and suggest that SR 27417 may be an effective prophylactic as well as a potent curative drug in this pathology.  相似文献   
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