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排序方式: 共有717条查询结果,搜索用时 385 毫秒
621.
622.
623.
Masaaki Shakudo MPH Misa Takegami RN MPH PhD Ai Shibata PhD Miki Kuzumaki MT Takahiro Higashi MD PhD Yasuaki Hayashino MD PhD MPH Yoshimi Suzukamo PhD Satoshi Morita PhD Michio Katsuki MD Shunichi Fukuhara MD DMSc FACP 《Journal of evaluation in clinical practice》2011,17(1):7-11
Objective We investigated whether providing participants in an exercise programme with regular feedback on their exercise progress affected their adherence to the programme regimen. Method We conducted a randomized controlled trial. Adult men and women with borderline hypertension and a body mass index ≥ 25.0 were randomized to two intervention groups (groups A and B) and one control group (group C) and were prescribed regular aerobic exercise. During the 12‐week study period, group A was provided with both feedback information on their exercise progress and a health letter, while group B was provided with the health letter only. The main outcome measure was exercise performance, per cent achievement of target exercise level (%) defined as the number of weeks during which the exercise target was reached divided by the number of weeks in the programme. Results were compared using the Kruskal–Wallis test. Results A total of 105 study subjects were randomized into three groups (A, n = 37; B, n = 37 and C, n = 31). Per cent achievement of target exercise level during the 12‐week period was highest in group A (26.5%), followed by groups B (22.9%) and C (17.4%) (P = 0.36). Subjects who received regular feedback during the exercise programme tended to have higher exercise performance. Conclusions In improving adherence to exercise intervention, the provision of regular feedback to participants in an exercise programme may be an effective intervention. 相似文献
624.
625.
BJ Poiesz ; S Dube ; B Jones ; V Bryz-Gornia ; MT Dean ; T Spicer ; J Hengst ; K Sayre ; E Esteban ; JF Ferrer 《Transfusion》1997,37(1):52-59
BACKGROUND : Human T-cell lymphoma/leukemia viruses types I and II (HTLV- I and HTLV-II) are related exogenous human retroviruses. The former is definitely pathogenic while disease association with the latter is unclear. There are two subtypes of HTLV-II, A and B. Currently, enzyme- linked immunosorbent assays (ELISAs) based on HTLV-I antigens are used to screen for the presence of HTLV-I and -II antibodies. Confirmation and subtyping are accomplished by Western blot (WB) or ELISAs based on HTLV-I whole viral antigens and/or HTLV-I and HTLV-IIA peptides. The sensitivity and specificity of these serologic assays were compared to those of HTLV-I and-II-specific polymerase chain reaction (PCR) assays in tests on samples from Indians from South America in whom the HTLV- IIB subtype is endemic. STUDY DESIGN AND METHODS : Sera from 246 Gran Chaco Indians were evaluated for HTLV antibodies with the use of four ELISAs (Retrotek HTLV-I; Cambridge Biotech rgp21 enhanced HTLV-I/II; Vironostika HTLV-I/II; and Select HTLV-I/II), and a WB assay. Peripheral blood leukocyte DNA from each Indian was analyzed for HTLV-I or HTLV-II pol DNA via PCR. Fifteen of the PCR-positive samples were further subtyped via cloning and sequencing and/or oligomer restriction. RESULTS : Ninety-seven samples (39%) were positive for HTLV- II by serologic and/or PCR assays. All 15 positive DNA samples that were further analyzed were of the HTLV-IIB subtype and were clustered as a highly conserved phylogenetic group. Comparative analyses indicate that the sensitivity and specificity of the various assays were: PCR, 97 and 100 percent; Retrotek, 70 and 91 percent; Cambridge Biotech, 74 and 96 percent; Vironostika, 73 and 99 percent; Select 72 and 98 percent; and WB, 70 and 100 percent. CONCLUSION : The sensitivities of the tested HTLV serologic assays were comparable. However, the specificity of the Retrotek ELISA was significantly lower than that of the others. When positive, the subtyping assays were very specific. However, PCR assays would seem preferable or to be a necessary adjunct for the sensitive detection of HTLV-IIB infection. 相似文献
626.
Manca F; Li Pira G; Fenoglio D; Valle MT; Kunkl A; Ferraris A; Lancia F; Saverino D; Mortara L; Balderas R 《Blood》1995,85(6):1547-1554
Because T-helper cells are critical for immune responses in retroviral infections, CD4+ T-cell lines specific for the human T-leukemia virus type 1 (HTLV-1) envelope have been generated from peripheral T lymphocytes of nonimmune donors to study their naive repertoire. Recombinant fragments (RE1, amino acids [aa] 26-200; RE3, aa 165-307; RE5, aa 308-401; and RE6, aa 165-401) of HTLV-1 envelope, whole envelope glycoprotein, and synthetic peptides were used to induce T- cell lines. CD4+ T-cell lines specific for one or more fragments were obtained from seven of eight individuals tested. T-cell lines generated against envelope glycoprotein from five of five donors did not cross- react with the RE fragments and vice versa. The lines specific for RE and env were mapped with overlapping peptides. The lines with single peptide (narrow) specificity contained a variety of clones that used different T-cell receptor V beta genes. These data (1) suggest that most of the normal individuals carry T-helper precursors specific for epitopes on HTLV-1 envelope; (2) indicate that heterogeneity of HTLV-1 envelope-specific T cells can be detected in the naive repertoire; and (3) define optimal antigenic preparations to be used to assess cellular immunity in HTLV-1-infected individuals. 相似文献
627.
628.
Fujita N; Suzuki K; Vanier MT; Popko B; Maeda N; Klein A; Henseler M; Sandhoff K; Nakayasu H; Suzuki K 《Human molecular genetics》1996,5(6):711-725
The four established or putative sphingolipid activator proteins derive
from a large precursor protein encoded by a single gene. In addition to
generating the four sphingolipid activator proteins, the precursor protein
is suspected of having functions of its own, as, for example, a lipid
binding/transport protein or a neurotrophic factor. The gene also appears
to encode the Sertoli cell major sulfated glycoprotein. Sequence
similarities have been noted with many other proteins of diverse functions.
One patient and a fetus in a single family with a complete defect of this
gene due to a mutation in the initiation codon exhibited complex
pathological and biochemical abnormalities. Mutant mice homozygous for an
inactivated gene of the sphingolipid activator protein precursor exhibit
two distinct clinical phenotypes-neonatally fatal and later-onset. The
latter develop rapidly progressive neurological signs around 20 days and
die by 35-38 days. At 30 days, severe hypomyelination and periodic
acid-Schiff-positive materials throughout the nervous system and in
abnormal cells in the liver and spleen are the main pathology. Most
prominently lactosylceramide, and additionally ceramide, glucosylceramide,
galactosylceramide, sulfatide, and globotriaosylceramide are abnormally
increased in the brain, liver, kidney, and their catabolism abnormally slow
in cultured fibroblasts. Brain gangliosides are generally increased,
particularly the monosialogangliosides. The clinical, pathological and
biochemical phenotype closely resembles that of the human disease. This
model not only allows further clarification of the physiological functions
of the four individual sphingolipid activator proteins but also should be
useful to explore putative functions of the precursor protein.
相似文献
629.
Vertebral osteomyelitis: assessment using MR 总被引:14,自引:0,他引:14
Modic MT; Feiglin DH; Piraino DW; Boumphrey F; Weinstein MA; Duchesneau PM; Rehm S 《Radiology》1985,157(1):157-166
Thirty-seven patients who were clinically suspected of having vertebral osteomyelitis were prospectively evaluated with magnetic resonance (MR), radiography, and radionuclide studies. These findings were correlated with the final clinical, microbiologic, or histologic diagnoses. Based on the results of these latter studies, 23 patients were believed to have osteomyelitis. MR examinations consisted of at least a sagittal image (TE = 30 msec, TR = 0.5 sec) and an image obtained at TE = 120 msec, TR = 2-3 sec. All patients underwent radiographic and MR examinations, 36 underwent technetium 99m-HDP bone scanning, and 20 patients underwent gallium 67 scanning. Nineteen patients underwent both bone and gallium scanning. The imaging studies were reviewed independently by investigators blinded to the final diagnoses. MR had a sensitivity of 96%, specificity of 92%, and accuracy of 94%. Combined gallium and bone scan studies (19 cases) had a sensitivity of 90%, specificity of 100%, and accuracy of 94%. Bone scans alone had a sensitivity of 90%, specificity of 78%, and accuracy of 86%. Plain radiographs had a sensitivity of 82%, specificity of 57%, and accuracy of 73%. The MR appearance of vertebral osteomyelitis in this study was characteristic, and MR was as accurate and sensitive as radionuclide scanning in the detection of osteomyelitis. 相似文献
630.