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排序方式: 共有1039条查询结果,搜索用时 15 毫秒
1.
Thomas J Birk Rodger D MacArthur Lynn M Lipton Sheldon D Levine 《The Journal of the Association of Nurses in AIDS Care》2002,13(6):20-24
The purpose of this study was to determine whether blood lipid and lipoprotein concentrations varied in 5 men with advanced HIV-1 infection after 12 months of aerobic exercise training. Prior to exercise, the mean baseline cholesterol and high-density lipoprotein cholesterol (HDL-C) serum concentration were each lower, and mean baseline triglyceride concentration was higher compared to a healthy population norm. Consistent exercise training for 12 months failed to significantly (p > .05) alter cholesterol or HDL-C. Triglyceride concentration was significantly (p < .05) elevated above baseline (63 mg/dL) regardless of exercise compliance. The results suggest that long-term exercise training cannot correct lipid profile abnormality, particularly hypertriglyceridemia, common to individuals with advanced HIV-1 infection. 相似文献
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Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
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6.
Ole Rintek Madsen Ulrik Birk Lauridsen Andreas Hartkopp Ole Helmer Sørensen 《European journal of applied physiology》1997,75(3):239-245
Dual energy x-ray absorptiometry (DEXA) offers the possibility of assessing regional soft tissue composition, i.e. lean mass (LM) and fat mass : LM may be considered a measure of muscle mass. We examined age-related differences in LM, percentage fat (%fat) and muscle strength in 100 healthy non-athletic women aged 18–87 years. Relationships between muscle strength and leg LM in 20 elite female weight lifters and in 18 inactive women with previous hip fractures were also studied. The LM and %fat of the whole body, trunk, arms and legs were derived from a whole body DEXA scan. Isokinetic knee extensor strength (KES) and flexor strength (KFS) at 30°?·?s–1 were assessed using an isokinetic dynamometer. The women aged 71–87 years had 35% lower KES and KFS than the women aged 18–40 years (P 0.0001). Differences in LM were less pronounced. The LM of the legs, for instance, was 15% lower in the old than in the young women (P 0.0001). In a multiple regression analysis with age, body mass, height and leg LM or KES as independent variables and KES or leg LM as the dependent variable, age was the most important predictor of KES (r partial?=??0.74, P 0.0001). The same applied to KFS. Body mass, not age, was the most important predictor of leg LM (r partial?=?0.65, P 0.0001) and of LM at all other measurement sites. The LM measured at different regions decreased equally with increasing age. The KES:leg LM ratio was negatively correlated with age (r?=??0.70, P 0.0001). The weight lifters had significantly higher KES:leg LM ratios than age-matched controls (+12%, P 0.0001) and vice versa for the women with previous hip fractures (–36%, P 0.0001). In conclusion, from our study it would seem that in healthy nonathletic women, age is a more important determinant of muscle strength than is LM as measured by DEXA. Muscle strengthening exercises and inactivity seem to have a considerably stronger influence on muscle strength than on LM. 相似文献
7.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
8.
9.
Identification and Characterization of a 29-Kilodalton Protein from Mycobacterium tuberculosis Culture Filtrate Recognized by Mouse Memory Effector Cells
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Ida Rosenkrands Peter Birk Rasmussen Markus Carnio Susanne Jacobsen Michael Theisen Peter Andersen 《Infection and immunity》1998,66(6):2728-2735
Culture filtrate proteins from Mycobacterium tuberculosis induce protective immunity in various animal models of tuberculosis. Two molecular mass regions (6 to 10 kDa and 24 to 36 kDa) of short-term culture filtrate are preferentially recognized by Th1 cells in animal models as well as by patients with minimal disease. In the present study, the 24- to 36-kDa region has been studied, and the T-cell reactivity has been mapped in detail. Monoclonal antibodies were generated, and one monoclonal antibody, HYB 71-2, with reactivity against a 29-kDa antigen located in the highly reactive region below the antigen 85 complex was selected. The 29-kDa antigen (CFP29) was purified from M. tuberculosis short-term culture filtrate by thiophilic adsorption chromatography, anion-exchange chromatography, and gel filtration. In its native form, CFP29 forms a polymer with a high molecular mass. CFP29 was mapped in two-dimensional electrophoresis gels as three distinct spots just below the antigen 85 complex component MPT59. CFP29 is present in both culture filtrate and the membrane fraction from M. tuberculosis, suggesting that this antigen is released from the envelope to culture filtrate during growth. Determination of the N-terminal amino acid sequence allowed cloning and sequencing of the cfp29 gene. The nucleotide sequence showed 62% identity to the bacteriocin Linocin from Brevibacterium linens. Purified recombinant histidine-tagged CFP29 and native CFP29 had similar T-cell stimulatory properties, and they both elicited the release of high levels of gamma interferon from mouse memory effector cells isolated during the recall of protective immunity to tuberculosis. Interspecies analysis by immunoblotting and PCR demonstrated that CFP29 is widely distributed in mycobacterial species. 相似文献
10.
J E Scherberich H W Birk W Schoeppe 《Zeitschrift für klinische Chemie und klinische Biochemie》1990,28(1):31-35
As a contribution to the noninvasive diagnosis of kidney damage, polyclonal antisera specifically directed against brush border surface glycoproteins of the proximal tubule of the human kidney were used in radioimmunoblotting studies for the assessment of kidney-tissue proteinuria. Urine specimens from healthy controls, from patients (n = 41) with various forms of renal involvement and from those suffering from symptomatic HIV-infection (AIDS) but having normal kidney function, were investigated for the excretion of kidney-derived membrane proteins. After SDS-polyacrylamide gel electrophoresis of urine samples and electroblotting of protein bands on nitrocellulose sheets, followed by incubation with the antibody and subsequently with 125I-labelled protein A, 3 major tubular glycoproteins (Mr 240 000, 160 000, 120 000) were revealed by autoradiography. The results indicate and increased shedding of epithelial membrane glycoproteins in the urine of patients with kidney lesions, and they also demonstrate the suitability of radioimmunoblotting for the determination of such tissue-antigens ("brush border-histuria"). 相似文献