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101.
Ostwald SK Leonard B Choi T Keenan J Hepburn K Aroskar MA 《Home health care services quarterly》1993,14(1):55-80
The purposes of this study were to compare the characteristics and support systems of caregivers of frail elderly and medically fragile children and to determine what factors discriminated between caregivers who could (and could not) continue to provide home health care. Caregivers of children were significantly more likely (chi 2 = 52.30)2), p = < .0000) to report that they were managing OK than caregivers of frail elderly. They also reported receiving more support and assistance from formal and informal sources, although in general, less than 30% of the caregivers received any help. Five variables (Mental impairment of the elder, poor physical and mental health of the caregiver, high monthly caregiving-related expenses, and use of paid in-home assistance) explained 35% of the variance between caregivers of frail elderly who were managing OK and those who were unable to continue to manage. Six variables (physical and mental impairment of the child, physical health of the caregiver, feeling like there were no alternative providers, time demand and lack of assistance from others) explained 26.57% of the variance between caregivers of children who were managing OK and those who were unable to continue to manage. The findings suggest that a strong objective stressor, combined with a lack of personal and social resources are associated with caregivers' perceptions that they cannot continue to manage home health care. 相似文献
102.
The Liposome as a Model Membrane in Correlations of Partitioning with α-Adrenoceptor Agonist Activities 总被引:1,自引:0,他引:1
The apparent partition coefficients of a group of imidazoline -adrenoceptor agonists in liposome/buffer systems (Km) and in the n-octanol/buffer system (P) have been compared in quantitative structure–activity relationships (QSAR) employing biological activities and receptor binding affinities. A parabolic relationship between log K
m
and log P was found, and log K
m
was greater than log P for all liposome compositions. In liposomes, log K
m
decreased in the order, negatively charged > neutral > positively charged. Overall, hyper- and hypotensive activities of these drugs correlated better with log K
m
than with log P; however, poor correlations were obtained between partition coefficients and in vitro binding affinities. Linear correlations of log K
m
with hypotensive activities were obtained with negatively charged liposomes, whereas correlations with hypertensive activities were obtained using positively charged liposomes. Multiple regressions of biological activities with binding affinities showed positive correlations with hypotensive but not hypertensive activities with or without the inclusion of log K
m
or log P. Thus, the liposome represents a more selective model membrane system than a bulk oil phase for predicting the biological activities of imidazoline -adrenoceptor agonists. 相似文献
103.
From the roasted seeds ofCassia tora L., a new naphthopyrone glycoside was isolated and characterized as 10-[(β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl)oxyl-5-hydroxy-8-methoxy-2-methyl-4H-naphtho
[1,2-b]pyran-4-one(isorubrofusarin gentiobioside). Along with isorubrofusarin gentiobioside, alaternin and adenosine were isolated
and identified. 相似文献
104.
The antioxidant activity ofArtemisia iwayomogi was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical The methanol extract
ofA. iwayomogi showed strong antioxidant activity, and thus fractionated with several solvents. The antioxidant activity potential of the
individual fraction was in the order of ethyl acetate>n-butanol>water>chloroform>n-hexane fraction. The ethyl acetate andn-butanol soluble fractions exhibiting strong antioxidant activity were further purified by repeated silica gel and Sephadex
LH-20 column chromatography. Antioxidant chlorogenic acid was isolated as one of the active principles from then-butanol fraction, together with the inactive components, 1-octacosanol, scopoletin, scopolin, apigenin 7,4′-di-O-methylether luteolin 6,3′-di-O-methylether (jaceosidin), apigenin 7-methylether (genkwanin), 2,4-dihydroxy-6-methoxyacetophenone 4-O-β-D-glucopyranoside and quebrachitol. The antioxidant activity of chlorogenic acid was comparable to that of L-ascorbic acid,
which is a well known antioxidant. 相似文献
105.
Lee BJ Ryu SG Choi HG Kim CK Parrott KA Ayres JW Sack RL 《Archives of pharmacal research》1997,20(6):555-559
The three different batches of an oral sustained release melatonin (MT) delivery system were prepared by aqueous-based fluid-bed coating of the sugar spheres for the evaluation ofin vitro release characteristics and plasma concentration profiles in human subjects. The MT contents in 20% coated sugar spheres of three batches (B1, B2 and B3) were 3.3+/-0.08, 2.4+/-0.1 and 2.5+/-0.13 mg per gram of coated sugar spheres, respectively. The release profiles of three different batches had a very similar fashion. However, the release half-lives (T(50%)) of MT from B1, B2 and B3 was 3.70+/-0.2, 5.2+/-0.2 and 4.9+/-0.07h, respectively. Plasma concentration profiles of sustained release 0.2mg melatonin-loaded sugar spheres containing 10% immediate release melatonin in gelatin capsules (B1 and B2) were then evaluated in human subjects. Thein vivo plasma concentration profiles of the two batches (B1 and B2) were very similar each other and located between the physiological endogenous ranges. The time to reach the peak concentration (T(max)) was more advanced in case of B1 when compared to B2. However, there was no statistically significant difference in the maximum concentration (C(max)) and the area under the curve (AUC) between B1 and B2. The AUC of melatonin-loaded sugar spheres containing 10% and 20% immediate release MT in human subjects had a good linearity between dose and AUC, regardless of the fraction of immediate release MT, indicating the first order elimination process of MT within these doses. The current oral sustained release MT delivery system may be utilized to treat circadian rhythm disorders if it is proven to be more clinically useful when compared to immediate release MT. 相似文献
106.
Novel 9-[2-fluoro-4-hydroxy-3-hydroxymethyl-2-butenyl]adenine and its related compounds were designed and synthesized as open-chain
analogues of neplanocin A. Alkylation of adenine or pyrimidine bases with the mesylate4 was chosen as a simple approach to the synthesis of 2-fluoro-2-butenylated nucleosides. Mesylate4 was prepared from dihydroxyacetone dimervia four steps in 58% overall yield. The synthesized compounds were evaluated their antiviral activity against HSV, HIV and Polio
viruses. 相似文献
107.
Hong Dae Choi Yong Sil Kowak Dek Hyun Geum Byeng Wha Son 《Archives of pharmacal research》1994,17(3):190-193
Friedel-Crafts reaction of isopropoxybenzene with methyl α-chloro-α-(methylthio)acetate1 afforded methyl α-methylthio-p-isopropoxyphenylacetate2d, which was readily converted into methyl p-isopropoxyphenylacetate3 by reductive desulfurization with zinc dust in acetic acid. Methylation of3 with sodium hydride and methyl iodide gave methyl α-(p-isopropoxyphenyl)propionate5. Methyl p-hydroxyphenylalkanoates (4, 6), useful intermediates for some medicines, were easily prepared by treatment of3 and5 with titanium tetrachloride, respectively. 相似文献
108.
Jack C. Kim Mi-Hyang Kim Seon-Hee Kim Soon-Kyu Choi 《Archives of pharmacal research》1995,18(6):449-453
The search for platinum (II)-based compounds with improved therapeutic properties was prompted to design and synthesize a new family of water-soluble, third generation cis-diamminedichloroplatinum (II) complexes linked to uracil and uridine. Six heretofore undescribed uracil and uridine-platinum (II) complexes are; [N-(2-aminoethyl)uracil-5-carboxamide]dichloroplatinum (II) (3a), [N-(2-aminoethyl)uracil-6-carboxamide]dichloroplatinum (II) (3b), [5-(2-aminoethyl)carbamoyl-2′,3′,5′,-tri-O-acetyluridine] dichloroplatinum (II) (6b), [5-(2-aminoethyl) carbamoylu-carbamoyl-2′,3′,5′,-tri-O-acetyluridine] dichloroplatinum (II) (6b), [5-(2-aminoethyl)carbamoyluridine]dichloroplatinum (II) (7a), [6-(2-aminoethyl)carbamoyluridine]dichloroplatinum (II) (7b). These analogues were prepared from the key starting materials, 5-carboxyuracil (1a) and 6-carboxyuracil (1b) which were reacted with ethylenediamine to afford the respective N-(2-aminoethyl)uracil-5-carboxamide (2a) and N-(2-aminoethyl)uracil-6-carboxamide (2b). The cisplatin complexes3a and3b were obtained through the reaction of the respective2a and2b with potassium tetrachloroplatinate (II). The heterocyclic nucleic acid bases1a and1b were efficiently introduced on the β-D-ribose ring via a Vorbruggen-type nucleoside coupling procedure with hexamethyldisilazane, trimethylchlorosilane and stannicchloride under anhydrous acetonitrile to yield the stereospecific β-anomeric 5-carboxy-2′,3′,5′-tri-0-acetyluridine (4a) and 6-carboxy-2′,3′,5′-tri-0-acetyluridine (4b), respectively. The nucleosides4a and4b were coupled with ethylenediamine to provide the respective 5-(2-aminoethyl)carbamoyl-2′,3′,5′-tri-0-acetyluridine (5a) and 6-(2-aminoethyl)carbamoyl-2′,3′,5′-tri-0-acetyluridine (5b). The diamino-uridines5a and5b were reacted with potassium tetrachloroplatinate (II) to give the novel nucleoside complexes,6a and6b, respectively which were deacetylated into the free nucleosides,7a and7b by the treatment with CH3ONa. The antitumor activities were evaluated against three cell lines (K-562, FM-3A and P-388). 相似文献
109.
We used our new flow cytometric method to measure benzo[a]pyrene-diolepoxide-deoxyribonucleic acid adduct levels in peripheral lymphocytes from healthy male smokers and nonsmokers. Smokers who had pack-years of 20 or more had significantly higher mean benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels than nonsmokers. In smokers, the adduct levels were correlated significantly with age, years of smoking, and pack-years, whereas daily tobacco consumption was not correlated with adduct levels. We also found a positive relationship between age and benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels in nonsmokers. Passive exposure to tobacco smoke was not associated with adduct levels. The results of our study indicate that benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct levels may be closely related to aging and that tobacco smoking-as well as other environmental factors-may play a role in the benzo[a]pyrene-diol-epoxide-deoxyribonucleic acid adduct formation. 相似文献
110.