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排序方式: 共有535条查询结果,搜索用时 31 毫秒
1.
Circannual variation in lymphocyte subsets, revisited 总被引:2,自引:0,他引:2
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply. 相似文献
2.
The family history in family practice: a questionnaire study 总被引:9,自引:7,他引:2
OBJECTIVES: Our aims were to investigate family medical history taking in
general practice, and to evaluate the value attached to the family medical
history as an aid to decision making in general practice. METHOD: A postal
questionnaire survey was conducted among all 291 GPs working within the
Calderdale and Kirklees Health Authority area. Each questionnaire was
followed by a reminder. The main outcome measures were answers to questions
on routine and opportunistic family history taking and a question about
transmitting knowledge about genetic risk to other members of the family.
Questions were also posed about the value attached to the family medical
history as an aid to decision making. RESULTS: A total of 193 GPs returned
the questionnaire (response rate 66.3%). On registration, 94.3% of GPs
indicated that enquiries were made about a family history of coronary heart
disease. Breast and colorectal cancer were specifically asked about by
48.4% and 30.7% of GPs, respectively. One-fifth of respondents indicated
that they asked a general question about family medical history. A little
over one-quarter of respondents indicated that they made opportunistic
enquiries about the family history or suggested that the patient should
inform other members of the family about possible risks. In the scenarios
highlighted in this study, the majority of respondents felt that the family
medical history had value as an aid to decision making. This was
particularly the case for checking a patient's cholesterol (92.1%) and for
initiating referrals in younger patients with possible cancer-related
symptoms (three-quarters of respondents). CONCLUSION: GPs value the family
medical history as an aid to decision making. Unfortunately, apart from
enquiries about coronary heart disease, routine or opportunistic family
history taking is not occurring in practice. Mechanisms need to be sought
to extract information from the family medical history so that it can be
more effectively used by GPs.
相似文献
3.
Radosława Nowak Elżbieta Oknińska‐Hoffmann Agata Skórka Dorota Gieruszczak‐Białek Maria Sawadro‐Rochowska 《American journal of medical genetics. Part A》2001,103(2):144-148
Wiedemann‐Rautenstrauch (neonatal progeroid) syndrome is an autosomal recessive condition with characteristic appearance of premature aging present at birth (aged face, natal teeth, and wrinkled skin). Other features of the syndrome are generalized lipoatrophy with specific fat accumulation in the lateral suprabuttock region, hypotrichosis, macrocephaly (pseudohydrocephalus), and mental retardation. We report on a new case that demonstrates all typical features of the syndrome. The girl is now 16 years and 10 months old and has had follow‐up from birth. We measured terminal restriction fragment (TRF) length to evaluate whether the patient's premature aging process is accompanied by shortening of telomere length in her cultured fibroblasts. Mean TRF of 13.5 kb found in our patient's fibroblasts is not shortened as compared to that of normal fibroblasts. Our results differ from those observed in Hutchinson‐Gilford progeria. © 2001 Wiley‐Liss, Inc. 相似文献
4.
A total of 10,542 breast biopsy specimens obtained between 1950 and 1968 were studied. Examples of atypical "ductal" (ADH) and atypical lobular hyperplasia (ALH), defined as having only some features of carcinoma in situ (CIS), were diagnosed in 3.6% of these specimens. In the same series, CIS was diagnosed in 1.7% of biopsy specimens excluding those with invasive cancer. The subsequent risk of invasive breast carcinoma after ALH or ADH was 4-5 times that of the general population. Follow-up was 90% successful and extended 17 years after biopsy. History of breast cancer in a mother, sister, or daughter doubled the risk of subsequent invasive carcinoma development (to 8 times for ALH and 10 times for ADH). The authors conclude that among the epithelial hyperplastic lesions of the human breast, a minority may be recognized by their resemblance to CIS which have a clinically significant elevation of subsequent breast cancer risk. This risk is one-half that of CIS. 相似文献
5.
RuthMabel Boytz Mikołaj Słabicki Sita Ramaswamy J. J. Patten Charles Zou Chengcheng Meng Brett L. Hurst Jinhua Wang Radosław P. Nowak Priscilla L. Yang Martin Sattler Richard M. Stone James D. Griffin Nathanael S. Gray Suryaram Gummuluru Robert A. Davey Ellen Weisberg 《Journal of medical virology》2023,95(1):e28157
Coronavirus disease 2019 (COVID-19) remains a major public health concern, and vaccine unavailability, hesitancy, or failure underscore the need for discovery of efficacious antiviral drug therapies. Numerous approved drugs target protein kinases associated with viral life cycle and symptoms of infection. Repurposing of kinase inhibitors is appealing as they have been vetted for safety and are more accessible for COVID-19 treatment. However, an understanding of drug mechanism is needed to improve our understanding of the factors involved in pathogenesis. We tested the in vitro activity of three kinase inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including inhibitors of AXL kinase, a host cell factor that contributes to successful SARS-CoV-2 infection. Using multiple cell-based assays and approaches, gilteritinib, nintedanib, and imatinib were thoroughly evaluated for activity against SARS-CoV-2 variants. Each drug exhibited antiviral activity, but with stark differences in potency, suggesting differences in host dependency for kinase targets. Importantly, for gilteritinib, the amount of compound needed to achieve 90% infection inhibition, at least in part involving blockade of spike protein-mediated viral entry and at concentrations not inducing phospholipidosis (PLD), approached a clinically achievable concentration. Knockout of AXL, a target of gilteritinib and nintedanib, impaired SARS-CoV-2 variant infectivity, supporting a role for AXL in SARS-CoV-2 infection and supporting further investigation of drug-mediated AXL inhibition as a COVID-19 treatment. This study supports further evaluation of AXL-targeting kinase inhibitors as potential antiviral agents and treatments for COVID-19. Additional mechanistic studies are needed to determine underlying differences in virus response. 相似文献
6.
Majdan M Jeleniewicz R Krzyzanowska E Majdan M 《Polskie Archiwum Medycyny Wewn?trznej》2004,112(1):805-809
Surface phenomena resulting from interactions between molecules occur commonly in nature. Peritoneal effluent is a mixture of organic and inorganic substances both macro- and micromolecular. Surfactants present in dialysate affect its surface properties. Among them are: proteins, phospholipids, fatty acids. Our aim in this study was to investigate relationships between peritoneal membrane solute transport characteristics and surface tension of peritoneal effluent. The study was conducted in 40 CAPD patients who were stable, without peritonitis (24 M, 16F), age 51.5 +/- 15.8 (range 30-79) mean CAPD duration 26.4 +/- 20.6 months (range 4-72). Standard peritoneal equilibration test (sPET) was done in all patients. Dialysate surface tension (ST) values after 4 hours dewell were determined using Wilhelmy Plate method. Mean ST values of individual dialysate sample based on 10 measurements were calculated. According to the PET values patients were divided into two groups: group 1 (high/high average transporters, n = 26) and group 2 (low average/low transporters, n = 14). Patients in group 1 had significantly lower ST of dialysate than patients in group 2 (51.2 +/- 4.8 vs 57.9 +/- 1.4 mN/m), p<0.01. The lowest values of ST (48.5 +/- 5 mN/m) were found in patients classified as high transporters (n = 8). Correlation's: significant negative correlation was found between ST and D4/P4 for creatinine (r = -0.45, p<0.005) and significant positive correlation between ST and D4/DO for glucose (r = 0.48, p = 0.003). We conclude that there are significant relationships between peritoneal transport status and surface tension of peritoneal effluent. High transporters have significantly higher concentrations of surfactants in dialysis effluent. 相似文献
7.
AIM
Drugs used for postoperative nausea and vomiting prophylaxis are believed to provoke torsadogenic changes in cardiac repolarization. The aim of this study was to assess the effect of small doses of droperidol on the parameters of cardiac repolarization, including the QTc interval and transmural dispersion of repolarization.METHODS
A total of 75 patients were randomly allocated to receive 0.625 or 1.25 mg droperidol or 8 mg ondansetron. The QTc interval was calculated using Bazett''s formula and the Framingham correction. The transmural dispersion of repolarization was determined as Tpeak–Tend time.RESULTS
Transient QT prolongation, corrected with both formulae, followed 1.25 mg of droperidol 10 min after administration. No change in the QTc value was observed in the other groups. When corrected with Bazett''s formula, QTc was prolonged above 480 ms in two patients receiving 1.25 mg droperidol (at the 10th and 20th minute of the study) and in one receiving ondansetron. No patients developed a QTcB prolongation over 500 ms. No increase above 480 ms was observed relative to the Framingham correction method. There were no significant differences in the Tpeak–Tend time either between or within the groups.CONCLUSION
In men without cardiovascular disorders small doses (1.25 mg) of droperidol prophylaxis induced transient QTc prolongation without changes in transmural dispersion of repolarization. The apparently low risk of the drug applies only in low risk male patients with a low pro-QTc score. 相似文献8.
9.
10.
K Piestrzeniewicz R Zwoliński M Maciejewski J Drożdz R Jaszewski 《Kardiologia polska》2012,70(8):839-840
We present a case of the left atrial myxoma 6 years after atrial fibrillation ablation. The initial diagnosis of the mass revealed on echocardiography was a thrombus. Failure of anticoagulant treatment and transesophageal echocardiography led to diagnosis of myxoma, confirmed intraoperatively and histologically. 相似文献