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排序方式: 共有9892条查询结果,搜索用时 15 毫秒
991.
Microdissection of chromosome band 11p15.5: characterization of probes mapping distal to the HBBC locus. 总被引:1,自引:0,他引:1
I Newsham U Claussen H J Lüdecke M Mason G Senger B Horsthemke W Cavenee 《Genes, chromosomes & cancer》1991,3(2):108-116
Both cytogenetic and molecular genetic analyses of the 11p15.5 subband suggest it may contain loci important in the genesis of a wide variety of tumors such as rhabdomyosarcomas and Wilms' tumors as well as the congenital tumors associated with the Beckwith-Wiedemann syndrome. As a first step in further defining the involvement of this chromosomal region in these various maladies, a library was constructed from the specific microdissection of chromosomal fragments representing 11p15.5-pter. Of 98 microclones analyzed, 31 identified single copy human DNA sequences, 21 of which mapped to 11p15.5 while 10 mapped proximal to the HBBC locus. Five of the 11p15.5-positioned microprobes detected restriction fragment length polymorphisms at their homologous genomic loci for various enzymes. These microprobes are now being utilized in several ways in order to address the underlying basis of the Beckwith-Wiedemann syndrome and its associated tumors. 相似文献
992.
The rostral ventromedial medulla (RVM) contains two classes of physiologically defined neurons, on-cells and off-cells, that are implicated in nociceptive modulation. In a continuing effort to detail the neural circuitry that underlies the activity of these two distinct neuronal types, the somatodendritic morphology of on- and off-cells was studied in the cat, rat, and ferret. In lightly anesthetized animals, on-cells increased and off-cells decreased their discharge rate during a withdrawal reflex evoked by noxious stimuli. Following their physiological characterization by using intracellular recording, on- and off-cells were injected with either horseradish peroxidase or biocytin and their somatodendritic arborizations were examined. Labeled on- and off-cells included fusiform and stellate cells of all sizes as well as large multipolar neurons. Although the somatic shape of both on- and off-cells in RVM was heterogeneous, off-cells tended to be fusiform neurons whose long axis was oriented mediolaterally. The dendritic domains of both on- and off-cells extended bilaterally past the lateral edge of the trapezoid body or pyramid and ventrally to, and sometimes including, the trapezoid body or pyramid. In contrast to their extensive mediolateral spread, the dendritic domains of both cell types were limited to the ventral half of the reticular formation and were compressed along the rostrocaudal axis. The dendritic arbor of individual on- and off-cells extended well beyond the cytoarchitectonic boundaries of any single nuclear region, within the domain delineated as the RVM. The spatial domains of the dendritic arbors of on- and off-cells are further evidence that the on- and off-cells throughout the RVM constitute an integrated unit in the modulation of nociceptive transmission. 相似文献
993.
994.
P R Mason D A Katzenstein T H Chimbira L Mtimavalye 《The Central African journal of medicine》1989,35(3):344-351
The microbial flora of the genital tract of 95 women who developed clinical signs of infection within 48 hr of vaginal delivery, Cesarean section delivery or abortion were compared with 111 women who delivered at the same hospital during the same time period but who showed no signs of sepsis. While there were no significant differences in the prevalence of most organisms in the lower genital tract of women with and without sepsis, there was evidence of a higher prevalence of gonococcal, chlamydial and anaerobic infection in the former. Gonococci were isolated from over 20 percent of untreated women with sepsis, more than three times the prevalence in controls. A third of the isolates were penicillinase-producing and another third showed in vitro resistance to penicillin. Chlamydial antigen was detected in 16-20 percent of women with sepsis following vaginal delivery or abortion, compared with 6 percent of controls. Neither gonococcal nor chlamydial infections were significantly associated with sepsis following Cesarean section delivery. Clue cells, indicative of G. vaginalis infection were noted in 20 percent of patients with sepsis compared with 7 percent of controls while amongst the other anaerobes only pigment producing Bacteroides were associated with sepsis. These findings suggest that antepartum investigations for clue cells, chlamydial antigen, gonococci and pigment producing anaerobes may identify patients most at risk from obstetric sepsis in Harare, and identify those for whom prophylactic administration of antibiotics may be of benefit. 相似文献
995.
Hyaluronan (HA) retention inside the synovial cavity of joints serves diverse protective roles. We tested the hypothesis that HA retention is mediated by the network of extracellular matrix proteins in the synovial lining. Cannulated rabbit knee joints were infused with HA solution with or without pretreatment by chymopapain, a collagen-sparing protease. Trans-synovial fluid escape rate was measured and, after a period of trans-synovial filtration, samples of intra-articular fluid and subsynovial fluid were analysed for HA to assess its trans-synovial ultrafiltration. In control joints, HA ultrafiltration was confirmed by postfiltration increases in intra-articular HA concentration (259 ± 17% of infused concentration) and reduced subsynovial concentration (30 ± 8%; n = 11). The proportion of HA molecules reflected by the synovium was 57–75%. Chymopapain treatment increased the hydraulic permeability of the synovial lining ∼13-fold, almost abolished the trans-synovial difference in HA concentration and reduced the HA reflected fraction to 3–7% ( n = 6; P < 0.001, ANOVA). Structural studies confirmed that chymopapain treatment depleted the matrix of proteoglycans but preserved its collagen. The findings thus demonstrate that HA ultrafiltration and synovial hydraulic permeability are determined by the network of non-collagen, extracellular matrix proteins. This may be important clinically, since protease activity is raised in rheumatoid arthritis, as are HA and fluid escape. 相似文献
996.
L J McGuigan R P Mason R Sanchez H A Quigley 《Investigative ophthalmology & visual science》1987,28(10):1625-1629
We studied the effect of two compounds, beta-aminopropionitrile (BAPN) and D-penicillamine on the success of experimental glaucoma filtering surgery in cynomolgus monkeys. All animals had laser-induced glaucoma and underwent punch sclerectomy operations. Eyes treated with BAPN or D-penicillamine maintained successful filtration for at least 3 days longer than nondrug-treated controls. This effect, while statistically significant (P less than 0.05), was temporary. The lack of more substantial improvement in prolonging filtering patency may have resulted from an inadequate effective drug concentration. Alternatively, these drugs may have limited potency because their action on new collagen synthesis affects only a minor component of the healing process that causes filter failure. 相似文献
997.
Background and Aim: Little is known about insurance agents' (insurers) satisfaction with the services provided by occupational therapists when they assess injured workers' activities of daily living (ADL). Demonstration of accountability and provision of high-quality services are important to the occupational therapy profession. The aim of this study was to evaluate insurers' overall satisfaction with occupational therapy ADL assessments for injured workers, including communication, timeliness of reports, equipment provision, knowledge of insurers' requirements and the workers' compensation process, and provision of a professional opinion. Relationships between insurers' overall satisfaction with ADL assessments, degree of experience in their job, formal qualifications and roles within their organisation were also investigated.
Method: A telephone survey was developed and administered to a sample of 40 claims officers and injury management advisors from 10 Victorian Work Cover Authority authorised agents.
Results: Insurers were generally satisfied with occupational therapy ADL assessments. They were less satisfied with occupational therapists' knowledge of workers' compensation system requirements and how occupational therapists made decisions when recommending household services.
Conclusion: To improve services to the insurance industry, occupational therapists need to better understand relevant legislative frameworks. 相似文献
Method: A telephone survey was developed and administered to a sample of 40 claims officers and injury management advisors from 10 Victorian Work Cover Authority authorised agents.
Results: Insurers were generally satisfied with occupational therapy ADL assessments. They were less satisfied with occupational therapists' knowledge of workers' compensation system requirements and how occupational therapists made decisions when recommending household services.
Conclusion: To improve services to the insurance industry, occupational therapists need to better understand relevant legislative frameworks. 相似文献
998.
999.
1000.
The affinities of a range of antipsychotic drugs at human hippocampal 5-HT1A receptors, defined by specific [3H]8-OH-DPAT binding, were determined. Clozapine demonstrated the highest affinity; all other antipsychotics studied demonstrated pK(i) values below 6.0 5-HT1A receptors are found on cortical glutamatergic neurons, a dysfunction of which may occur in schizophrenia. Binding at this site indicates a possible mechanism contributing to the unique efficacy of clozapine in the treatment of some schizophrenic patients. 相似文献