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排序方式: 共有2581条查询结果,搜索用时 46 毫秒
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Alzheimer''s disease. Beta-amyloid precursor protein expression in the nucleus basalis of Meynert. 下载免费PDF全文
G. M. Murphy Jr B. D. Greenberg W. G. Ellis L. S. Forno S. M. Salamat P. A. Gonzalez-DeWhitt D. E. Lowery J. R. Tinklenberg L. F. Eng 《The American journal of pathology》1992,141(2):357-361
The nucleus basalis of Meynert (nbM) was examined using immunocytochemistry for beta-amyloid precursor protein (beta APP) expression in Alzheimer's disease (AD). In mild AD cases, light labeling of the cell body and proximal processes was observed, and small intracellular structures were labeled rarely. In the more severe cases, intense cytoplasmic beta APP labeling was seen, often along with small beta APP-positive structures. Double-labeling experiments demonstrated that in the more severe cases these small structures were also decorated by a neurofibrillary tangle (NFT) antiserum. Other neurons in the severe cases showed incorporation of beta APP into large inclusions, which were also labeled with the NFT antiserum. However, some large inclusions in the severe cases were labeled by the NFT antiserum but contained no beta APP. Extraneuronal NFTs did not show beta APP labeling and did not react with an antibody to the beta-amyloid peptide. These results suggest that increased expression of beta APP coincides with intracellular NFT formation in the nbM, but that the formation of extraneuronal NFTs results in a loss of beta APP immunoreactivity. 相似文献
25.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
26.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
27.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
28.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
29.
S Narindrasorasak D E Lowery R A Altman P A Gonzalez-DeWhitt B D Greenberg R Kisilevsky 《Laboratory investigation; a journal of technical methods and pathology》1992,67(5):643-652
BACKGROUND: In vivo amyloid formation apparently involves several extracellular matrix components that are usually found associated with basement membranes. These include laminin, heparan sulfate proteoglycan, collagen type IV, and entactin. These components have also been found in neuritic plaques. We have therefore been examining interactions between extracellular matrix components and the Alzheimer's amyloid precursors (AAPs). EXPERIMENTAL DESIGN: Binding interactions of laminin with AAP-695, -751, and -770 were examined using a solid phase enzyme-linked immunosorbent assay technique. RESULTS: Objective, quantitative analyses of the laminin AAP-695, -751, and -770 binding data reveal two binding sites for laminin, with Kd values of 1 x 10(-10) M and 1 x 10(-8) M. Zinc and dithiothreitol profoundly stimulate laminin binding to AAPs. Furthermore, zinc fingers were found in the laminin amino acid sequences. Previous binding studies of AAPs with the basement membrane heparan sulfate proteoglycan revealed similar affinities. A particular order of addition of laminin and heparan sulfate proteoglycan to AAPs can be demonstrated. CONCLUSIONS: These avid interactions with extracellular matrix proteins likely reflect normal functions of the AAPs and may be involved in nucleation events in Alzheimer-type amyloid formation. 相似文献
30.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献