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71.
Evaluated the stress effects of major surgery on 26 white male patients. The State-Trait Anxiety Inventory (STAI) and Kincannon's Mini-Mult version of the MMPI were given 18-24 hr. before surgery and 3-9 days postsurgery after the S was informed he was recovering without complications. Mean STAI A-State scores were much higher prior to surgery than after; STAI A-Trait scores were essentially the same. Patients with high- and low-A-Trait scores showed similar presurgery-postsurgery changes in A-State. Scores on the Mini-Mult were essentially unchanged by the stresses associated with surgery. Results indicate that the threat of imminent surgery produced elevations in anxiety as an emotional state, but did not affect anxiety proneness (A-Trait). (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Dithiocarboxylation of some halogenated pyridine sulphones with carbon disulphide and sodium hydride leads to the formation of thiomethyl derivatives via Smiles rearrangement of the initially produced dianion, fragmentation and subsequent methylation. In one instance the pyridino[2,3-b]-1,4-dithiine 7 was obtained. The thioether 2d was also converted into a thiomethyl derivative when subjected to the same reaction sequence.  相似文献   
73.
This work evaluates chronic safety in middle‐aged ovariectomized rats supplemented with different dosages of green tea polyphenols (GTP) in drinking water. The experiment used 6‐mo‐old sham (n = 39) and ovariectomized (OVX, n = 143) female rats. All sham (n = 39) and 39 of the OVX animals received no GTP treatment and their samples were collected for outcome measures at baseline, 3 mo, and 6 mo (n = 13 per group for each). The remaining OVX animals were randomized into 4 groups receiving 0.15%, 0.5%, 1%, and 1.5% (n = 26 for each) of GTP (wt/vol), respectively, in drinking water for 3 and 6 mo. No mortality or abnormal treatment‐related findings in clinical observations or ophthalmologic examinations were noted. No treatment‐related macroscopic or microscopic findings were noted for animals administered 1.5% GTP supplementation. Throughout the study, there was no difference in the body weight among all OVX groups. In all OVX groups, feed intake and water consumption significantly decreased with GTP dose throughout the study period. At 6 mo, GTP intake did not affect hematology, clinical chemistry, and urinalysis, except for phosphorus and blood urea nitrogen (increased), total cholesterol, lactate dehydrogenase, and urine pH (decreased). This study reveals that the no‐observed‐adverse‐effect level (NOAEL) of GTP is 1.5% (wt/vol) in drinking water, the highest dose used in this study.  相似文献   
74.
The synthesis of 5H-thiopyrano[4,3-b]pyridines, 8H-thiopyrano[3,4-b]pyridines, 1H-thiopyrano[3,4-c]pyridines and 1H-thiopyrano[4,3-c]pyridines from methyl pyridine esters 5–8 and nitriles 17–20 by simple photobromination, followed by reaction of the intermediate bromomethyl derivative with methyl thioglycolate and subsequent base induced cyclisation of the latter are reported.  相似文献   
75.
76.
The chemically crosslinked network structures make epoxies, the most common thermosets, unable or hard to be recycled, causing environmental problems and economic losses. Epoxy-based vitrimers, polymer networks deriving from epoxy resins, can be thermally malleable according to bond exchange reactions (BERs), opening the door to recycle epoxy thermosets. Here a series of experiments were carried out to study the effects of processing conditions (such as particle size distributions, temperature, time, and pressure) on recycling of an epoxy-anhydride vitrimer. Polymer powders from the epoxy-anhydride vitrimer with different size distributions were prepared and characterized, and the influence of particle size on the mechanical performance of recycled epoxy-anhydride vitrimers was investigated by dynamic mechanical analysis and uniaxial tensile test. Experimental results demonstrated that finer polymer powders can increase the contacting surfaces of recycled materials and thus result in high quality of recycled materials. In addition, the influences of other treating parameters, such as temperature, time, and pressure, were also discussed in this study. Adjusting these treating parameters can help the design of an optimized reprocessing procedure to meet practical engineering applications.  相似文献   
77.
The interactions of the 936-species phages sk1, jj50, and 64 with the cell surface of Lactococcus lactis LM0230 were analyzed. Cell envelopes (walls + plasma membrane), cell wall, or plasma membrane from L. lactis ssp. lactis LM0230 each inactivated the phages in vitro. However, other 936-species phages kh and P008, which do not infect strain LM0230, were not inactivated by any of the subcellular fractions. Treating cell walls or plasma membrane with the cell wall hydrolase mutanolysin eliminated inactivation of phage sk1. This suggested that intact cell wall fragments were required for inactivation. A role for plasma membrane in phage sk1 inactivation was further investigated. Boiling, washing in 2 M KCl, 8 M urea, or 0.1 M Na(2)CO(3)/pH 11, or treating the plasma membrane with proteases did not reduce adsorption or inactivation of phage. Adding lipoteichoic acid or antibodies to lipoteichoic acid did not reduce inactivation of phage in a mixture with membrane, suggesting that lipoteichoic acid was not involved. Inactivation by envelopes or cell wall correlated with ejection of DNA from the phage sk1 capsid. Although calcium is required for plaque formation, it was not required for adsorption, inactivation, or ejection of phage DNA by envelopes or cell wall. The results suggest that at least for phages sk1, jj50, and 64, adsorption and phage DNA injection into the host does not require a host membrane protein or lipoteichoic acid, and that cell wall components are sufficient for these initial steps of phage infection.  相似文献   
78.
The roles of Bcl-2 protein and the protein ratio of Bcl-2/Bax in regulating cell growth in various lymphoma cell lines were examined. A dose-dependent decrease in Bcl-2 protein expression was observed in the different lymphomas incubated with lipid-incorporated bcl-2 antisense oligonucleotides (L-bcl-2). Growth inhibition was observed in a transformed follicular lymphoma (FL) cell line, which has the t(14;18) translocation and Bcl-2 protein overexpression. One of the mechanisms by which L-bcl-2 growth inhibition is mediated in these transformed FL cells might be through apoptotic induction, because the treated cells had an increased apoptotic index and showed the typical DNA fragmentation. These studies indicate that Bcl-2 protein is critical in the growth regulation of transformed FL cells. L-bcl-2 did not induce growth inhibition in lymphoma cells not expressing Bcl-2 or Bax protein. Thus, the protein ratio of Bcl-2/Bax may also be important in regulating the growth of these lymphomas.  相似文献   
79.
A double-blind, placebo-controlled study was carried out to test the clinical efficacy and safety of local nasal immunotherapy (LNIT) in powder form. Twenty-two patients suffering from allergic rhinitis strictly associated with early spring symptoms, with positive skin prick tests and RAST for birch-alder, all responders to a specific nasal provocation test (NPT), received randomly active or placebo treatment for 4 months. Immunotherapy consisted of administration of a set of capsules containing progressively increasing amounts of birch (Betula pendula) and speckled alder (Alnus incana) allergens in powder form with controlled granulometry. The active (birch-alder) and placebo (lactose) group completed the treatment according to a similar schedule. During the pollen season (March-April), the patients who took the active treatment reported less sneezing and rhinorrhea than the placebo group, on the basis of a symptoms score, and the differences were statistically significant; the need for drugs (terfenadine) was also significantly reduced. These findings agreed well with the results of specific NPT after the treatment; only patients in the active group had a higher threshold dose of nasal specific reactivity to birch-alder allergens than in tests before the LNIT.  相似文献   
80.
Dyslipidaemia may be treated with a number of safe and effective pharmacological agents that target specific lipid disorders through a variety of mechanisms. The bile-acid sequestrants--cholestyramine and colestipol--primarily decrease LDL cholesterol by binding bile acids, thereby decreasing intrahepatic cholesterol, and by increasing the activity of LDL receptors. Nicotinic acid lowers LDL cholesterol and triglyceride by decreasing VLDL synthesis and by decreasing free fatty acid mobilization from peripheral adipocytes. The HMG-CoA reductase inhibitors--fluvastatin, lovastatin, pravastatin and simvastatin--lower LDL cholesterol by partially inhibiting HMG-CoA reductase (the rate-limiting enzyme of cholesterol biosynthesis) and by increasing the activity of LDL receptors. The fibric-acid derivatives--bezafibrate, ciprofibrate, clofibrate, fenofibrate and gemfibrozil--primarily decrease triglyceride by increasing lipoprotein lipase activity and by decreasing the release of free fatty acids from peripheral adipose tissue. Probucol decreases LDL cholesterol by increasing non-receptor-mediated LDL clearance; as an anti-oxidant, probucol also decreases LDL oxidation; oxidized LDL which is thought to lead to atherogenesis. Although these agents have been proven safe in clinical trials, like any drug, they carry the risk for adverse effects. The bile-acid sequestrants may cause constipation, reflux oesophagitis, and dyspepsia, and may bind coadministered medications such as digitalis glycosides, beta blockers, warfarin, and exogenous thyroid hormone. Nicotinic acid use is commonly associated with flushing and pruritus and may also cause non-specific gastrointestinal complaints, hepatotoxicity (hepatic necrosis, hepatitis, or elevated liver enzymes), gout, myolysis, decreased glucose tolerance and increased fasting glucose levels, and ophthalmological complications including decreased visual acuity, toxic amblyopia, and cystic maculopathy. The HMG-CoA reductase inhibitors may produce liver enzyme elevations, creatine kinase elevations and rhabdomyolysis. The combination of a reductase inhibitor and a fibrate increases the risk for rhabdomyolysis. Possible adverse effects of the fibric-acid derivatives include abdominal discomfort, nausea, flatulence, increased lithogenicity of bile, liver enzyme elevations and creatine kinase elevations. Probucol may increase the QTc interval and may cause non-specific gastrointestinal complaints.  相似文献   
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