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排序方式: 共有662条查询结果,搜索用时 31 毫秒
631.
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634.
Background
Providing care for mental health problems concerns General Practitioners (GPs), Private Psychiatrists (PrPs) and Public Psychiatrists (PuPs). As patient distribution and patterns of practice among these professionals are not well known, a survey was planned prior to a re-organisation of mental health services in an area close to Paris 相似文献635.
目的 :确定人巨细胞病毒 PPU L44蛋白单克隆抗体 CH13在 PPU L44上的抗原决定簇位置 ,探讨随机多肽文库在研究相互作用蛋白质的氨基酸序列方面的应用。方法 :用 CH13在一个随机多肽文库中筛选出能与CH13结合的克隆 ,测定上述克隆随机多肽的 DNA序列 ,用随机多肽的氨基酸同源序列与 PPUL44蛋白质的氨基酸序列比较。结果 :能与 CH13结合的随机多肽的氨基酸序列显示出高度的一致性 ;随机多肽同源序列NEGEAFGPDVSG与 PPUL44蛋白位于第 32 1~ 332的氨基酸序列高度同源 ;而随机多肽序列 FQIL VCVESVL R与 PPU L44位于第 181~ 184的氨基酸序列有 4个相邻的氨基酸一致。结论 :CH13的抗原决定簇位于 PPU L44蛋白第 32 1~ 332氨基酸序列附近 ;CH13与 PPU L44位于第 181~ 184氨基酸序列可能有一定反应。随机多肽文库在研究相互作用蛋白质的氨基酸序列方面具有广泛的应用前景。 相似文献
636.
B. G. Schneider V. Pekkel C. H. Shelton D. R. Pulitzer D. C. Allred S. G. Hilsenbeck C. H. Hensel H. A. Rodríguez-Martínez M. E. Gutiérrez-Díaz C. 《Virchows Archiv : an international journal of pathology》1994,424(2):187-193
Gastric cancer is more than twice as common in Hispanics as in Anglos in Texas, while colorectal cancer is almost twice as common in Anglos as Hispanics. To test the hypothesis that mutations in the p53 tumour suppressor gene are involved in these differences, we examined 131 gastric and 138 colorectal cancers from Hispanic and Anglo patients from South Texas and Mexico using immunohistochemistry (IHC) as a screening assay for p53 mutations. The fraction of p53 positive cases was not significantly different in gastric cancers from Hispanics compared to Anglos (43% versus 61%, respectively, p=0.13) or in colorectal cancer (57% versus 58%, respectively, p=1.0), suggesting that p53 mutations are not involved in causing the different incidences of these cancers in these populations. In addition, the types of p53 mutations arising in gastric tumours from Hispanic patients were consistent with those reported in gastric tumours in other populations. Sequencing of mutations in five gastric cancers revealed two G: C to A: T transitions, two A: T to G: C transitions and one complex deletion. In contrast with findings in studies in other tumour types, neither stage nor survival was associated with p53 positive staining by IHC in either gastric or colorectal tumours in this study. Positive p53 immunostaining was associated with the diffuse histological subtype in gastric carcinoma (p=0.05) and high histological grade in colorectal carcinoma (p=0.04). 相似文献
637.
Araneda OF García C Lagos N Quiroga G Cajigal J Salazar MP Behn C 《European journal of applied physiology》2005,95(5-6):383-390
Lung oxidative stress (OS) was explored in resting and in exercising subjects exposed to moderate and high altitude. Exhaled
breath condensate (EBC) was collected under field conditions in male high-competition mountain bikers performing a maximal
cycloergometric exercise at 670 m and at 2,160 m, as well as, in male soldiers climbing up to 6,125 m in Northern Chile. Malondialdehyde
concentration [MDA] was measured by high-performance liquid chromatography in EBC and in serum samples. Hydrogen peroxide
concentration [H2O2] was analysed in EBC according to the spectrophotometric FOX2 assay. [MDA] in EBC of bikers did not change while exercising at 670 m, but increased from 30.0±8.0 to 50.0±11.0 nmol l−1 (P<0.05) at 2,160 m. Concomitantly, [MDA] in serum and [H2O2] in EBC remained constant. On the other hand, in mountaineering soldiers, [H2O2] in EBC under resting conditions increased from 0.30±0.12 μmol l−1 at 670 m to 1.14±0.29 μmol l−1 immediately on return from the mountain. Three days later, [H2O2] in EBC (0.93 ±0.23 μmol l−1) continued to be elevated (P<0.05). [MDA] in EBC increased from 71±16 nmol l−1 at 670 m to 128±26 nmol l−1 at 3,000 m (P<0.05). Changes of [H2O2] in EBC while ascending from 670 m up to 3,000 m inversely correlated with concomitant variations in HbO2 saturation (r=−0.48, P<0.05). AMS score evaluated at 5,000 m directly correlated with changes of [MDA] in EBC occurring while the subjects moved
from 670 to 3,000 m (r=0.51, P<0.05). Lung OS may constitute a pathogenic factor in AMS. 相似文献
638.
Detection of precursor Th cells in mesenteric lymph nodes after oral immunization with protein antigen and cholera toxin 总被引:2,自引:0,他引:2
We have characterized the earliest antigen-specific Th cells in murine
mesenteric lymph nodes (MLN), following oral immunization with the hen egg
lysozyme (HEL) as antigen and cholera toxin (CT) as adjuvant. We did this
by analyzing in vitro proliferation and cytokine production in response to
HEL by the MLN T cells. MLN cells taken 5 days after a single oral
immunization with HEL and CT provided the earliest source of proliferating
HEL-specific T cells. This proliferation was completely inhibited by
anti-IL-2, but not inhibited by anti-IL-4 antibody. IL-2 protein was
detected in culture supernatants but not IL- 4 using ELISA or bioassays.
IL-4 mRNA was not found in responding cells using RT-PCR. Some of the day 5
MLN cultures produced IFN-gamma in response to HEL, but isolated T cells
from the same MLN did not. Exogenous IL-4 alone did not stimulate day 5 MLN
T cells, but IL-4 did synergize with HEL to induce a large proliferative
response. The data indicate that the HEL-specific CD4 T cell pool in MLN 5
days after oral immunization is composed of undifferentiated precursor Th
cells. These cells have the potential for IL-2 production and IL-4R
expression upon re-stimulation in vitro.
相似文献
639.
Three genes on 11p15.5 are known to undergo genomic imprinting. The gene
for insulin-like growth factor II (IGF2) is normally expressed from the
paternal allele, while H19 and p57KIP2, a cyclin-dependent kinase
inhibitor, are expressed from the maternal allele. Five germline balanced
chromosomal rearrangement breakpoints from patients with Beckwith-Wiedemann
syndrome (BWS) have been mapped to 11p15.5 between p57KIP2 and IGF2, and
all are derived from the maternal chromosome. By positional cloning from
BWS breakpoints, we have isolated a gene 100 kb and 65 kb centromeric to
the proximal end of this BWS breakpoint cluster and p57KIP2, respectively.
This gene is homologous to yeast nucleosome assembly protein (NAP1) and to
a human homologue of NAP1, and we designate it hNAP2 (human nucleosome
assembly protein 2). hNAP2 diverges in its expression pattern from IGF2,
H19, and p57KIP2, and it shows biallelic expression in all tissues tested.
Thus, hNAP2 is functionally insulated from the imprinting domain of 11p15.
相似文献
640.
M Wilson M Dordea A Light MP Serra SR Aspinall 《Annals of the Royal College of Surgeons of England》2015,97(3):198-203