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1.
Use of a scanning laser three-dimensional digitizer to evaluate dimensional accuracy of dental impression materials. 总被引:1,自引:0,他引:1
A steel die was machined to represent a dental arch with teeth prepared for complete crowns. Impressions and casts were made from the die, and critical dimensions were measured by two methods--one using micrometers and the other a scanning laser three-dimensional (3-D) digitizer. The digitizer recorded measurements were more precise than the micrometer's and virtually eliminated operator error because the acquisition of data was automatic. The digitizer could also be useful for high-precision analyses of the dimensional accuracy of dental impression materials, but the cost and complexity of the instrument makes it less desirable for low-precision work. 相似文献
2.
Prolonged Replication of a Type 1 Vaccine-Derived Poliovirus in an Immunodeficient Patient 总被引:16,自引:5,他引:16 下载免费PDF全文
Olen M. Kew Roland W. Sutter Baldev K. Nottay Michael J. McDonough D. Rebecca Prevots Linda Quick Mark A. Pallansch 《Journal of clinical microbiology》1998,36(10):2893-2899
VP1 sequences were determined for poliovirus type 1 isolates obtained over a 189-day period from a poliomyelitis patient with common variable immunodeficiency syndrome (a defect in antibody formation). The isolate from the first sample, taken 11 days after onset of paralysis, contained two poliovirus populations, differing from the Sabin 1 vaccine strain by ~10%, differing from diverse type 1 wild polioviruses by 19 to 24%, and differing from each other by 5.5% of nucleotides. Specimens taken after day 11 appeared to contain only one major poliovirus population. Evolution of VP1 sequences at synonymous third-codon positions occurred at an overall rate of ~3.4% per year over the 189-day period. Assuming this rate to be constant throughout the period of infection, the infection was calculated to have started ~9.3 years earlier. This estimate is about the time (6.9 years earlier) the patient received his last oral poliovirus vaccine dose, approximately 2 years before the diagnosis of immunodeficiency. These findings may have important implications for the strategy to eliminate poliovirus immunization after global polio eradication. 相似文献
3.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
4.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
5.
Identification of a new locus for autosomal dominant non-syndromic hearing impairment (DFNA7) in a large Norwegian family 总被引:3,自引:0,他引:3
Fagerheim T; Nilssen O; Raeymaekers P; Brox V; Moum T; Elverland HH; Teig E; Omland HH; Fostad GK; Tranebjaerg L 《Human molecular genetics》1996,5(8):1187-1191
Hereditary hearing impairment affects about 1 in 1000 newborns. In most
cases hearing loss is non-syndromic with no other clinical features, while
in other families deafness is associated with specific clinical
abnormalities. Analysis of large families with non-syndromic and syndromic
deafness have been used to identify genes or gene locations that cause
hearing impairment. The present report describes a large Norwegian family
with autosomal dominant non-syndromic, progressive high tone hearing loss
with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was
obtained with the microsatellite marker D1S196. Analysis of recombinant
individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104
and D1S466. The region contains several attractive candidate genes. This
report supports the idea of extensive genetic heterogeneity in hereditary
hearing impairment and represents the first localization of a deafness gene
in a Norwegian family.
相似文献
6.
Hawley CJ Ratnam S Pattinson HA Quick SJ Echlin D 《Journal of psychopharmacology (Oxford, England)》1996,10(3):241-245
Nineteen major depressed patients, resistant to previous pharmacotherapies, were treated by the addition of moclobemide (up to 600 mg/day) to paroxetine or fluoxetine (20 mg/day) for 6 weeks in an open study to assess the adverse events and tolerability. There were 77 emergent events, insomnia, headache, nausea and dizziness being the most common. Many events were rated as severe. The high rate of adverse events suggests that there may be clinically significant interactions between moclobemide and SSRIs. However, the uncontrolled data on effectiveness is encouraging and the combination deserves further attention as a strategy for treating intractable major depression. 相似文献
7.
Specific staining of the axon membrane at nodes of Ranvier with ferric ion and ferrocyanide 总被引:1,自引:0,他引:1
Ferric ion and ferrocyanide were used as stains for light and electron microscopy of peripheral nerves. In rat sciatic nerves, it was found that ferric ion preferentially binds to the cytoplasmic surface of the axon membrane at nodes of Ranvier but not at internodal regions. In myelinated axons in the electric organ of the gymnotid fish, Sternarchus albifrons, the small excitable nodes are similarly stained, but the larger inexcitable nodes are not stained by ferric ion. Staining of the inner surface of the nodal membrane appears to be related to a structural specialization of this membrane, rather than accessibility to stain. Our data thus show a chemical differentiation of the inner surface of the axon membrane between nodes and internodes in normal peripheral nerve fibers and between the inner surface of the axon membrane at active nodes, inactive nodes, and the internodes in the Sternarchus electrocyte axons. 相似文献
8.
The emergency department evaluation had two primary objectives: 1) to determine the accuracy of the oral medication history given at arrival at the emergency department and 2) to determine how often the emergency department physician may prescribe medications which when taken with current medications, may cause a potential drug interaction. Data were collected from 228 emergency department visits of clinic patients 65 years old and older. The average number of medications reported by the patients' medication history was 3.0 +/- 2.3 (range 0-13). The number of medications the patient "forgot" was 1.3 +/- 1.8 (range 0-9). A complete medication history was given by 50.4% of patients. There was an upward trend that correlated with an increased chance for an incomplete medication history as the total number of current medications increased. The rate of a potentially significant drug interaction between a newly prescribed medication in the emergency department and current medications was 3.4% for patients receiving a new medication. 相似文献
9.
Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications. 相似文献
10.
At the mid-radius, pre-pubertal asthmatic children had smaller periosteal and endosteal circumferences and thicker cortical shells compared to controls, when assessed by peripheral quantitative computed tomography. Asthmatics had diminished periosteal expansion for muscle size, suggesting that asthma, its treatment, or its effects on physical activity had resulted in impaired adaptation of bone to muscle loading. Alterations in cortical bone geometry might explain the increased fracture risk in asthmatic children. 相似文献