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81.
Peripheral blood CD4+CD8+ lymphocytes in cynomolgus monkeys are of resting memory T lineage 总被引:2,自引:0,他引:2
In this study, we analyzed peripheral blood CD4+CD8+ double-positive (DP)
lymphocytes in adult cynomolgus monkeys (Macaca fascicularis). Forty of 55
monkeys had > 5% of the peripheral blood DP subpopulation (9.3 +/- 5.9%;
mean +/- SD) in peripheral blood lymphocytes (PBL) in contrast to a low
percentage of peripheral blood DP cells in humans and mice. In a
cross-sectional study, the peripheral blood DP cells were found to increase
in proportion with age. To clarify whether peripheral blood DP lymphocytes
were immature precursors released from thymus without prior
differentiation, the expressions of CD8 chains and CD1b on peripheral blood
DP lymphocytes were compared with those on thymocytes. The peripheral blood
DP lymphocytes were CD8 alpha + beta- and CD1b-, while thymic DP
lymphocytes were CD8 alpha + beta + and CD1b +, suggesting that the
peripheral blood DP cells are extrathymic T lymphocytes. Furthermore, the
peripheral blood DP lymphocytes exhibited a resting memory T cell phenotype
with CD2hiCD3+CD28-CD29hiCD49dhiCD69- CD80lo. Taken together, adult
cynomolgus monkeys possess a unique peripheral blood DP T cell
subpopulation which expresses a resting memory T cell phenotype. In
addition, similar phenotypic properties of DP lymphocytes were distributed
in the spleen and lymph nodes, although the proportion was less in the
spleen and much less in lymph nodes than in PBL.
相似文献
82.
HaiYan Song MScMed LongQian Liu MMed PhD Rita Sum BOptom Mavis Fung BOptom Maurice KH Yap PhD MCOptom FAAO 《Clinical & experimental optometry》2011,94(6):563-567
Background: The aim was to examine the progression and regression of diabetic retinopathy within a four‐year period in a Chinese population with type 2 diabetes mellitus in a community optometry clinic in Hong Kong. Methods: During the period May 2005 to November 2009, 5,160 patients with type 2 diabetes mellitus who had attended at least two diabetic retinopathy screening sessions at a community optometry clinic were included as subjects in this study. All had retinal photographs taken of both eyes, which were of sufficiently good quality for grading. For the purpose of this study, diabetic retinopathy grading was based on the results of the worst eye. The main outcomes were the within four‐year incidence of diabetic retinopathy and the incidence of progression and regression of diabetic retinopathy. Results: Of the 5,160 subjects in this study, 3,647 had no diabetic retinopathy, while 1,513 had diabetic retinopathy at the baseline visit. Of those 3,647 subjects with no diabetic retinopathy, the within four‐year cumulative incidence of any diabetic retinopathy, mild or moderate non‐proliferative diabetic retinopathy and sight‐threatening diabetic retinopathy was 15.16 per cent, 14.45 per cent, 0.69 per cent and 0.03 per cent, respectively. Of those 1,513 subjects with diabetic retinopathy at baseline, the within four‐year progression incidence of diabetic retinopathy was 6.61 per cent and the regression incidence of diabetic retinopathy was 45.54 per cent. Conclusion: The high regression incidence of diabetic retinopathy suggests that it might not be necessary for all patients with diabetes to be screened annually. Other methods to determine the screening frequency for an individual patient should be explored. 相似文献
83.
INTRODUCTION
This study aimed to examine the various factors associated with inpatient falls among patients with and without dementia in a hospital setting.METHODS
This was a retrospective one-year study using data collected from Singapore General Hospital''s electronic reporting system for inpatient falls.RESULTS
In the study period, 298 patients aged ≥ 65 years fell during their hospital stay. The majority of the patients (n = 248) did not have dementia. In our study, fallers with dementia were more likely to use ambulatory aids, be visually impaired and have urinary incontinence. More patients with dementia than those without had a history of previous falls, and were placed on fall precaution with restricted freedom of movement, which at times, included restraints. However, the difference between patients who were put on restraints and those who were allowed to move freely was not statistically significant. The majority of falls in both groups occurred at the bedside. We found that fallers without dementia were more likely to fall during the morning shift, whereas fallers with dementia were more likely to fall during the night shift. Fallers with dementia were more likely to be confused at the time of the fall.CONCLUSION
In our study, we found that fallers with dementia were more likely to have visual impairment, have urinary incontinence, use walking aids, and to be confused and physically restrained at the time of the fall. The fallers without dementia in our study may have undiagnosed dementia. 相似文献84.
MD Savvidou R Akolekar E Zaragoza LC Poon KH Nicolaides 《BJOG : an international journal of obstetrics and gynaecology》2009,116(5):643-647
Objective To compare urinary placental growth factor (PlGF) concentration at 11+0 to 13+6 weeks of gestation in women who subsequently develop pre-eclampsia with normotensive controls.
Design Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting Routine antenatal visit in a teaching hospital.
Population Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures Development of pre-eclampsia.
Results In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy. 相似文献
Design Nested case–control study within a prospective study for first trimester prediction of pre-eclampsia.
Setting Routine antenatal visit in a teaching hospital.
Population Fifty-two women who developed pre-eclampsia and 52 controls matched for gestational age and sample storage time.
Methods Urinary PlGF concentration and PlGF to creatinine ratio were measured in women who developed pre-eclampsia and their matched controls. Comparisons between groups were performed using Student's t test.
Main outcome measures Development of pre-eclampsia.
Results In the pre-eclampsia group, the median urinary PlGF concentration (20.6 pg/ml, interquartile range [IQR] 9.1–32.0 pg/ml) and median urinary PlGF to creatinine ratio (1.6 pg/mg, IQR 1.2–2.5 pg/mg) were not significantly different from the control group (11.8 pg/ml, IQR 5.5–29.8 pg/ml, P = 0.1 and 1.7 pg/mg, IQR 1.2–2.3 pg/mg, P = 0.3, respectively). There were no significant differences between women with early-onset pre-eclampsia requiring delivery before 34 weeks ( n = 13) and those with late-onset pre-eclampsia ( n = 39) and between women with pre-eclampsia and fetal growth restriction (FGR) ( n = 25) and those with pre-eclampsia and no FGR ( n = 27) in either median PlGF concentration or median urinary PlGF to creatinine ratio.
Conclusions The development of pre-eclampsia is not preceded by altered urinary PlGF concentration in the first trimester of pregnancy. 相似文献
85.
Katharina H. Ruebel BS Long Jin MD Shuya Zhang BS Bernd W. Scheithauer MD Dr. Ricardo V. Lloyd MD PhD 《Endocrine pathology》2001,12(3):281-289
Recent studies have shown that methylation of the CpG island within the p16/CDKN2A/MTS1 (p16) gene is associated with loss
of expression of p16 protein in pituitary tumors. We analyzed a series of 21 pituitary adenomas and three normal pituitaries
along with a human pituitary cell line (HP75) for methylation of exon 1 by methylation-specific PCR, immunohistochemistry,
and Western blotting. PCR analysis showed that 5/7 (71%) of null cell adenomas, but only 2/7 (29%) gonadotroph tumors were
hypermethylated. In addition, 1 of 2 ACTH tumors but no GH (n=4) or PRL (n=1) adenoma examined were hypermethylated. Immunostaining and Western blot analysis of protein expression supported the methylation-specific
PCR analyses.
These results show that p16 gene silencing by hypermethylation is more common in null cell adenomas compared to other nonfunctioning
adenomas such as gonadotroph tumors and that the role of p16 in the pathogenesis of pituitary adenomas is restricted to specific
tumor subtypes.
Supported in part by NIH CA90249 and by a grant from the Jarislowsky Foundation. 相似文献
86.
PK Tran A Haworth F Foroudi A Paneghel AG Herschtal KH Tai SG Williams S Soteriou M Laferlita GM Duchesne 《Journal of Medical Imaging and Radiation Oncology》2009,53(6):574-580
The aim of this study is to prospectively evaluate and model surrogate explanatory variables (SEVs) of target coverage and rectal dose pertaining to soft tissue anatomy visualised on cone beam computed tomography (CBCT) for incorporation into post‐prostatectomy treatment coverage verification protocols. Twenty post‐prostatectomy patients treated with conformal prostate bed radiotherapy (64–74 Gy) underwent CBCT daily at fractions 1 to 5, and then weekly. Treatment coverage was defined on each CBCT using ‘PTV95’, percentage of the CBCT PTV covered by original treatment fields, and ‘RECTD50’, dose delivered to 50% of CBCT rectal volume by original treatment fields. Three candidate SEVs for treatment coverage were defined for each scan: anterior rectal wall movement, change in bladder length and bladder base movement. Both anterior rectal wall movement and increase in bladder length predicted for the decreased PTV95 (P < 0.001 for each). Anterior movement of the anterior rectal wall predicted for increased RECTD50 (P < 0.001). Predictive models for the PTV95 and RECTD50 that accept the significant SEVs as inputs were developed. We developed simple CBCT‐acquired soft tissue anatomic surrogate measures that signal changes in target coverage and rectal dose during post‐prostatectomy radiotherapy. Conventional bony anatomy patient position verification protocols were inadequate in accounting for soft tissue target and organ variation seen with CBCT. 相似文献
87.
Robert Temple Shaw T. Chen Yung-Chi Cheng Steven KH AUNG lan KY Tsang Peter A. Frandsen 《中国结合医学杂志》2008,14(1)
The 3rd World Integrative Medicine Congress (3rd WIMCO) was held on September 22-24, 2007 in Guangzhou, China. The Congress has showed the academic achievements of integrative medicine in the recent five years covering a wide range of fields, such as basic and experimental research; clinical research; theory, education and management research; new drug research and development; and application of evidence-based medicine. 相似文献
88.
PJ Garry ; DJ VanderJagt ; SJ Wayne ; KH Koehler ; RL Rhyne ; TL Simon 《Transfusion》1991,31(8):686-692
Iron stores were observed in 57 healthy elderly volunteers, between 63 and 77 years of age, who donated 5 units of blood over approximately 1 year. An equal number of nondonors who contributed approximately 7 mL of blood at each visit for iron status measurements only were seen at the same frequency as the donor population. At entrance to the study, iron stores in women and men averaged 724 and 875 mg, respectively. After five donations, mean iron stores dropped to 67 mg in women (n = 27) and 362 mg in men (n = 30); four women (15%) became iron deficient, while two (7%) developed iron deficiency anemia. Three men (10%) developed iron deficiency, but none were found to be anemic. Mean intakes of iron were 23.3 and 22.5 mg per day, respectively, for women and men. Iron intakes were adequate to meet iron requirements of nondonors, but they were not sufficient to halt the steady decrease in iron stores among the donor population, in whom iron absorption increased from approximately 5 percent at entrance to 14 percent at the time of the fifth donation. In summary, healthy elderly persons may contribute to the national blood resource; however, donations should probably be limited to less than five per year or donors should regularly take an iron supplement to preserve reasonable amounts of iron reserves. 相似文献
89.
We compared the efficiency of removing cosmetic eyeliner deposits from soft contact lenses with a variety of surfactant cleaners. Four types of daily cleaners were used to clean two groups of soft contact lenses (Group 1 and Group 2 : FDA classification) contaminated with an eyeliner. The lenses were cleaned in a Clensatron 700CL Automatic Contact Lens Cleaning unit. The amount of lens contamination before and after cleaning was quantified by digitising a photograph of the lens surface. We found that: 1. the eyeliner was less likely to adhere to Group 2 lenses, 2. the efficiency of removing eyeliner was independent of the cleaning solutions we used; when contaminated, Group 2 lenses were generally easier to clean, 3. the Clensatron unit was not as efficient as digital rubbing in removing the eyeliner. 相似文献
90.
Normal human spermatozoa carry either the X or the Y chromosome. The
differences between X and Y spermatozoa (X and Y haploid cells) may exist
in two areas: the different chromosomes (i.e. different kinds and numbers
of genes) and the different sperm structures and functions (i.e. different
genetic expression). The aim of this study was to determine whether there
are any size between X and Y spermatozoa and whether sperm size and shape
varies between men. Identification of the Y (and X inferred) status of
individual spermatozoa was carried out by polymerase chain reaction (PCR),
amplifying the putative testis- determining gene (SRY) together with a
control gene (ZP3). PCR amplification of 871 out of 895 (97.3%) single
motile spermatozoa showed that 444 (51.0%) were Y and 427 (49.0%) were
X-bearing spermatozoa. Of 233 normally-shaped but immobilized spermatozoa,
217 (93.1%) were photographed and measured. Statistically, the length,
perimeter and area of the sperm heads, and the length of the sperm necks
and tails of X-bearing spermatozoa were significantly larger and longer
than those of Y-bearing spermatozoa. Some peculiarities (or variations) in
the X and Y sperm shape and size in individual donors were found. The
pre-screening by micro-measurement of these specific haploid
characteristics of individual spermatozoa in different donors, which may be
closely related to their different genetic conditions (or diseases), may be
important in human medicine and animal husbandry, especially in sperm
prefertilization diagnosis.
相似文献