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961.
962.
S S Yoon H D Youn C Suh Y J Bang S J Choi B K Kim N K Kim E C Kim 《Journal of Korean medical science》1987,2(4):255-258
One case of arthritis complicating leukemia is described in which leukemic cells were identified in synovial fluid by light microscopy. Although arthritis is a well-known manifestation of leukemia with an incidence of 13.5%, the pathogenesis often is unclear, and the direct demonstration of leukemic cells in synovial fluid has been very uncommon. A 16 year-old male patient was admitted due to left elbow joint pain and swelling. Synovial fluid examination revealed blast cells and this finding has directed to a final diagnosis of acute lymphoblastic leukemia. 相似文献
963.
Gene delivery to glioma cells in rat brain by grafting of a retrovirus packaging cell line 总被引:9,自引:0,他引:9
M P Short B C Choi J K Lee A Malick X O Breakefield R L Martuza 《Journal of neuroscience research》1990,27(3):427-439
Retrovirus vectors only integrate into the genome of dividing cells and can thus be used to selectively infect tumor cells in the adult rat brain. Gene delivery was assessed by using the retrovirus BAG vector, which bears the Escherichia coli lacZ gene under the MoMLV LTR promoter-enhancer element, and by histochemical staining for bacterial beta-galactosidase activity. Direct injection of this vector (90-900 cfu) into the adult rat brain, with or without prior inoculation of C6 glioma cells (2 x 10(5) cells) resulted in labeling of only a few cells as assessed 1 week later. When the psi 2-BAG packaging line was grafted into the brain, labeled psi 2-BAG cells could be found after 1 day, but not after 5 days, following grafting, suggesting that the grafted cells had been rejected and that no endogenous cells had integrated released vector, or that expression of lacZ had been turned off. In contrast, when the psi 2-BAG packaging line was grafted into a brain region, which had been inoculated previously with rat C6 glioma cells (2 x 10(5) cells), beta-galactosidase labeling of these tumor cells, identified by immunocytochemistry for glial fibrillary acidic protein and S100, could be demonstrated 10 days later. Thus, grafting of retrovirus packaging lines into adult brain provides a mean to infect tumor cells in situ. The grafted packaging cells may continue to release retrovirus particles for an extended period, thus infecting more cells at the stage of division appropriate for viral integration, as compared to inoculation of the virus alone. Grafting of retrovirus packaging cell lines could be used to selectively deliver "killer" or "suppressor" genes to tumor cells in the brain to curtail their growth. 相似文献
964.
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
965.
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
966.
Parith Wongkittichote Tae-Ik Choi Oc-Hee Kim Kacie Riley Dwight Koeberl Vinodh Narayanan Keri Ramsey Chris Balak Charles E. Schwartz Anna Maria Cueto-Gonzalez Francina Munell Casadesus Cheol-Hee Kim Marwan S. Shinawi 《Clinical genetics》2023,103(2):167-178
ZC4H2 (MIM# 300897) is a nuclear factor involved in various cellular processes including proliferation and differentiation of neural stem cells, ventral spinal patterning and osteogenic and myogenic processes. Pathogenic variants in ZC4H2 have been associated with Wieacker-Wolff syndrome (MIM# 314580), an X-linked neurodevelopmental disorder characterized by arthrogryposis, development delay, hypotonia, feeding difficulties, poor growth, skeletal abnormalities, and dysmorphic features. Zebrafish zc4h2 null mutants recapitulated the human phenotype, showed complete loss of vsx2 expression in brain, and exhibited abnormal swimming and balance problems. Here we report 7 new patients (four males and three females) with ZC4H2-related disorder from six unrelated families. Four of the 6 ZC4H2 variants are novel: three missense variants, designated as c.142T>A (p.Tyr48Asn), c.558G>A (p.Met186Ile) and c.602C>T (p.Pro201Leu), and a nonsense variant, c.618C>A (p.Cys206*). Two variants were previously reported : a nonsense variant c.199C>T (p.Arg67*) and a splice site variant (c.225+5G>A). Five patients were on the severe spectrum of clinical findings, two of whom had early death. The male patient harboring the p.Met186Ile variant and the female patient that carries the p.Pro201Leu variant have a relatively mild phenotype. Of note, 4/7 patients had a tethered cord that required a surgical repair. We also demonstrate and discuss previously under-recognized phenotypic features including sleep apnea, arrhythmia, hypoglycemia, and unexpected early death. To study the effect of the missense variants, we performed microinjection of human ZC4H2 wild-type or variant mRNAs into zc4h2 null mutant zebrafish embryos. The p.Met186Ile mRNA variant was able to partially rescue vsx2 expression while p.Tyr48Asn and p.Pro201Leu mRNA variants were not. However, swimming and balance problems could not be rescued by any of these variants. These results suggest that the p.Met186Ile is a hypomorphic allele. Our work expands the genotypes and phenotypes associated with ZC4H2-related disorder and demonstrates that the zebrafish system is a reliable method to determine the pathogenicity of ZC4H2 variants. 相似文献
967.
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
968.
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
969.
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
970.
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