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排序方式: 共有3859条查询结果,搜索用时 12 毫秒
31.
Dick DM Foroud T Edenberg HJ Miller M Bowman E Rau NL DePaulo JR McInnis M Gershon E McMahon F Rice JP Bierut LJ Reich T Nurnberger J 《American journal of medical genetics》2002,114(4):407-412
Analyses of a replication sample of families collected as part of the National Institute of Mental Health (NIMH) Genetics Initiative for bipolar disorder provide further evidence for linkage to a region of chromosome 16. Families who had a bipolar I (BPI) proband and at least one BPI or schizoaffective, bipolar type (SABP) first-degree relative were ascertained for the purpose of identifying genes involved in bipolar affective disorder. A series of hierarchical models of affected status was used in linkage analyses. Initial genetic analyses of chromosomes 3, 5, 15, 16, 17, and 22, completed at Indiana University in 540 subjects from 97 families, suggested evidence of linkage to chromosomes 5, 16, and 22 [Edenberg et al., 1997: Am J Med Genet 74:238-246]. Genotyping was subsequently performed on these chromosomes in a replication sample of 353 individuals from 56 families. Nonparametric linkage analyses were performed using both affected relative and sibling pair methods. Analyses in the new sample on chromosome 16, using the broadest model of affected status, corroborate previously reported suggestive linkage to the marker D16S2619. Combining the initial and replication samples further increased the evidence of linkage to this region, with a peak lod score of 2.8. 相似文献
32.
33.
Immunohistochemistry of neurone specific enolase with gamma subunit specific anti-peptide monoclonal antibodies. 总被引:1,自引:0,他引:1
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AIMS--To investigate the application in immunohistochemistry of gamma-subunit specific anti-peptide monoclonal antibodies to human neurone specific enolase (NSE); and to determine their reactivity with formalin fixed, wax embedded sections of normal tissue and neuroendocrine tumours. METHODS--Immunohistochemical staining was performed on sections of formalin fixed, wax embedded tissue with two monoclonal antibodies (NSE-P1 and NSE-P2) raised against different synthetic peptides specific for the gamma subunit of human enolase (neurone specific enolase). RESULTS--Both antibodies gave strong immunostaining in normal tissues and cells known to contain NSE. There was no immunoreactivity in tissues containing either the alpha alpha or beta beta isozymes of enolase. The reactivity of the antibodies with a range of neuroendocrine tumours was also studied and both antibodies gave strong immunostaining of tumour cells in the different tumours. CONCLUSIONS--The use of synthetic peptides from defined regions of a molecule as immunogenes provides antibodies of high specificity. These monoclonal antibodies to NSE are ideally suited for immunohistochemical studies and they should be particularly useful in histopathology as they react with epitopes which are resistant to formalin fixation and wax embedding. 相似文献
34.
Richard D. W. Hain David Chitayat Robert Cooper Elizabeth Bandler Barry Eng David H. K. Chui John S. Waye Melvin H. Freedman 《Human mutation》1994,3(3):239-242
We describe a normal neonate who presented at four days of age with asymptomatic cyanosis. There was no evidence of cardiac or pulmonary abnormality and an extended family history included 13 other affected family members with asymptomatic cyanosis lasting one to three months. Polymerase chain reaction (PCR) amplification and direct nucleotide sequencing of the proband's Gγ chain gene revealed the mutation at codon 92 (CAC→TAC) previously shown in haemoglobin FM-Fort Ripley (α2γ2Gγ 92 (F8) His→Tyr). This is the first family with Hb FM-Fort Ripley reported so far. It demonstrates autosomal dominant inheritance of this condition and incomplete penetrance. © 1994 Wiley-Liss, Inc. 相似文献
35.
The HLA-D/DR region in man encodes major determinants which stimulate T lymphocytes to proliferation. The genetic organization of this region is apparently complex and is at present largely unknown. One obstacle is the scarcity and quality of available typing reagents. In an attempt to obtain high quality anti-DR sera, a series of active immunizations was performed between highly selected, healthy unrelated donors and recipients.
One recipient (AR8) was immunized using cells incompatible for HLA-A2, B40 (w60), Cw3 and DIDRw6 and readily developed anti-A2 and B40 antibodies but no anti-C, DR, or other antibodies. When tested against his HLA genotypically fully identical brother using the cellular MLC, PLT, or CML techniques before immunization, results were mutually negative as expected. Following immunization, however, AR8 was able to mount MLC, PLT, and possibly CML responses against lymphocytes from the brother while the reverse combinations remained negative. When tested in the family the trait(s) thus identified seems to be maternally inherited.
These results suggest the existence of minor histocompatibility determinants encoded from regions not closely linked to HLA. The brother of AR8 and the immunizing donor thus seem to share one or more determinants not possessed by AR8. 相似文献
One recipient (AR8) was immunized using cells incompatible for HLA-A2, B40 (w60), Cw3 and DIDRw6 and readily developed anti-A2 and B40 antibodies but no anti-C, DR, or other antibodies. When tested against his HLA genotypically fully identical brother using the cellular MLC, PLT, or CML techniques before immunization, results were mutually negative as expected. Following immunization, however, AR8 was able to mount MLC, PLT, and possibly CML responses against lymphocytes from the brother while the reverse combinations remained negative. When tested in the family the trait(s) thus identified seems to be maternally inherited.
These results suggest the existence of minor histocompatibility determinants encoded from regions not closely linked to HLA. The brother of AR8 and the immunizing donor thus seem to share one or more determinants not possessed by AR8. 相似文献
36.
Melvin D. Trousdale Ronald E. Paque Timothy Nealon Charles J. Gauntt 《Infection and immunity》1979,23(2):486-495
Ten temperature-sensitive (ts) mutants isolated from a myocarditis-inducing wild-type (WT) coxsackievirus B3 parent did not induce myocarditis in adolescent CD-1 mice. An avirulent prototype ts mutant from one of the three complementation groups adsorbed to murine cardiac tissue, as did WT virus. Heart tissues from mice inoculated with WT virus contained 100- to 1,000-fold more virus than heart tissues from mice inoculated with any of the three prototype ts mutants. WT virus exhibited a greater capsid stability and a higher efficiency of replication at 37 degrees C than any of the three prototype ts mutants. All three prototype ts mutants induced less interferon in vivo than WT virus. Cell-mediated immune responses, assessed by the cell migration inhibition assay, were different in mice inoculated with WT virus when compared to ts 5 mutant virus. Peritoneal exudate cells from mice inoculated with WT but not ts 5 virus reacted specifically against antigens in WT virus HeLa cell lysates and antigens extracted with KCl from cardiac tissues of mice inoculated with WT virus. Cardiac tissues of mice inoculated with WT but not ts 5 virus contained KCl-extractable antigens which were able to specifically inhibit the migration of peritoneal exudate cells taken from mice immunized with WT virus. Therefore, ts 5 neither elicited a measurable cell-mediated immune response nor induced antigens in cardiac tissues which were immunoreactive with sensitized-(WT virus)-peritoneal exudate cells. Of 9 revertant viruses isolated from the 10 ts mutants, 5 showed covariance in ability to replicate at 39.5 degrees C and capacity for induction of myocarditis. Some revertants exhibited a reduced capsid thermostability compared to WT virus but yet retained the capacity for induction of myocarditis. The data suggest that induction of myocarditis by coxsackievirus B3 variants depends on a combination of several variables, including capsid stability, capacity for replication at 37 degrees C, and expression of the three identified genes. All three prototype ts mutants served as vaccine viruses in preventing myocarditis in adolescent mice subsequently challenged with WT virus. However, all three prototype ts mutants and their revertant variants retained partial to complete lethality in CD-1 neonates. 相似文献
37.
William W. Dawson Donald Armstrong Melvin Greer Tom M. Maida Don A. Samuelson 《Documenta ophthalmologica. Advances in ophthalmology》1985,60(2):163-171
Two adults with mild dementia and a history of memory loss and disequilibrium were seen in the eye clinic following complaints of acuity loss in the 20/30–20/70 (Snellen) range. Results from the fundus examination of one patient were entirely normal; the other showed minimal vascular attenuation and optic atrophy. Electrophysiology was remarkable: (1) Photopic ERG b-waves were reduced, delayed, and showed pronounced oscillations. (2) EOG light-rise potentials were absent or very small. (3) Binocular pattern-VER signals showed addition of the monocular signal. Scotopic ERG signals were normal. Brain biopsy and microscopy showed intercellular, autofluorescent ceroid deposits which provided a clear diagnosis of Kufs disease. Histology of model animal retinal cells show ceroid deposits in cell classes implicated by the human retinal signals. The cluster of electrophysiological results point toward early changes in the pigment epithelium and inner plexiform layer cells as a means of non-invasive diagnosis. 相似文献
38.
S Y Melvin 《Primary care》1990,17(1):47-57
Syphilis has persisted for centuries, yet over the last few years with public emphasis on "safe sex" practices there is still a resurgence of this disease. Control of this potentially devastating illness cannot be achieved by physicians alone. It requires a combined effort from the public, educators, government, and the medical community. Physicians may contribute by patient education, frequent testing of all individuals at high risk, and treatment and close follow-up of patients and contacts. 相似文献
39.
Yang Weilian Barth Rolf F. Rotaru Joan H. Moeschberger Melvin L. Joel Darrel D. Nawrocky Marta M. Goodman Joseph H. 《Journal of neuro-oncology》1997,33(1-2):59-70
Boronophenylalanine (BPA) has been used for boron neutron capture therapy (BNCT) of brain tumors in both experimental animals and humans. The purpose of the present study was to determine if the efficacy of BNCT could be enhanced by means of intracarotid (i.c.) injection of BPA with or without blood-brain barrier disruption (BBB-D) and neutron irradiation using a rat brain tumor model. For biodistribution studies, F98 glioma cells were implanted stereotactically into the brains of Fischer rats, and12 days later BBB-D was carried out by i.c. infusion of 25% mannitol (1.373 mOsmol/ml), followed immediately by i.c. administration of 300, 500 or 800 mg of BPA/kg body weight (b.w.). At the 500 mg dose a fourfold increase in tumor boron concentration (94.5 g/g) was seen at 2.5 hours after BBB-D, compared to 20.8 g/g in i.v. injected animals. The best composite tumor to normal tissue ratios were observed at 2.5 hours after BBB-D, at which time the tumor: blood (T: Bl) ratio was10.9, and the tumor: brain (T: Br) ratio was 7.5, compared to 3.2 and 5.0 respectively for i.v. injected rats. In contrast, animals that had received i.c. BPA without BBB-D had T: Bl and T: Br ratios of 8.5 and 5.9, respectively, and the tumor boron concentration was 42.7g/g. For therapy experiments, initiated 14 days after intracerebral implantation of F98 glioma cells, 500 mg/kg b.w. of BPA were administered i.v. or i.c. with or without BBB-D, and the animals were irradiated 2.5 hourslater at the Brookhaven Medical Research Reactor with a collimated beam of thermal neutrons delivered to the head. The mean survival time for untreated control rats was 24 ± 3 days, 30 ± 2 days for irradiated controls, 37 ± 3 days for those receiving i.v. BPA, 52 ± 15 days for rats receiving i.c. BPA without BBB-D, and 95 ± 95 days for BBB-D followed by i.c. BPA and BNCT. The latter group had a 246% increase in life span (ILS) compared to untreated controls and a 124% ILS compared to that of i.v. injected animals. These survival data are the best ever obtained with the F98 glioma model and suggest that i.c. administration of BPA with or without BBB-D may be useful as a means to increase the efficacy of BNCT. 相似文献
40.
Background: Recent data suggest that children have a higher incidence of recurrence than adults after nonoperative treatment of primary
spontaneous pneumothorax (PSP). Video-assisted thoracoscopic surgery (VATS) allows efficacious therapy with significantly
less morbidity. We attempt to define the most cost-effective clinically efficacious strategy using VATS to manage pediatric
PSP.
Methods: We retrospectively reviewed all admissions to a tertiary care children's hospital for PSP between January 1, 1991 and June
30, 1996.
Results: Fifteen children had 29 primary or recurrent PSPs. Mean patient age was 14.8 ± 1.1 years, boy–girl ratio 4:1, median body
mass index 18 (normal, 20–25), and 67% of pneumothoraces left sided. All patients were managed initially nonoperatively: 14
with tube thoracostomy drainage and 1 with oxygen alone. Of the children initially managed nonoperatively, 57% had a recurrent
pneumothorax, and 50% of these patients eventually developed contralateral pneumothoraces. Nonoperative treatment for recurrence
resulted in a 75% second recurrence rate. In contrast, eight children who underwent operative management had a 9% incidence
of recurrence. The total for charges accrued in treating 29 pneumothoraces in these 15 patients was approximately $315,000.
In the same population, the estimated charges for initial nonoperative therapy followed by bilateral thoracoscopy after a
single recurrence would be $230,000.
Conclusions: A cost-effective treatment strategy for pediatric primary spontaneous pneumothorax is tube thoracostomy at first presentation,
followed by VATS with thoracoscopic bleb resection and pleurodesis for patients who experience recurrent pneumothorax.
Received: 15 May 1998/Accepted: 15 January 1999 相似文献