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11.
We investigated a university-affiliated cohort of SARS-CoV-2 Omicron BA.2 infections in Arizona, USA. Of 44 cases, 43 were among students; 26 persons were symptomatic, 8 sought medical care, but none were hospitalized. Most (55%) persons had completed a primary vaccine series; 8 received booster vaccines. BA.2 infection was mild in this young cohort.  相似文献   
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Oral anticoagulant therapy, which is used for prophylaxis and management of thrombotic disorders, causes similar reductions in plasma levels of vitamin K-dependent procoagulant and anticoagulant clotting factor zymogens. When we measured levels of circulating activated protein C, a physiologically important anticoagulant and anti-inflammatory agent, in patients on oral anticoagulant therapy, the results unexpectedly showed that such therapy decreases levels of activated protein C substantially less than levels of protein C, prothrombin, and factor X, especially at lower levels of prothrombin and factor X. Thus, we suggest that oral anticoagulant therapy results in a relatively increased expression of the protein C pathway compared with procoagulant pathways not only because there is less prothrombin to inhibit activated protein C anticoagulant activity, but also because there is a disproportionately higher level of circulating activated protein C.  相似文献   
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In 111 lupus patients we compared the potential of the IgG and IgM anticardiolipin antibody (ACA) enzyme linked immunosorbent assay (ELISA) and four different lupus anticoagulant (LAC) assays (partial thromboplastin time (PTT) of a 1:1 mixture of patient and control plasma with phospholipids from animal (PTT-st) or human brain (PTT-HB); PTT with dilutions of human brain phospholipids (PL dilution); and kaolin clotting time of mixtures of patient and control plasma (KCT] to identify patients with thrombosis (26/111), fetal loss (19/46), and/or thrombocytopenia (11/106). The highest specificity for thrombosis (87%) was found with PTT-HB and PL dilution (sensitivity 65%, detection rate 61%); for fetal loss (93%) with PL dilution (sensitivity 47%; detection rate 82%), and for thrombocytopenia (83%) with KCT (sensitivity 82%; detection rate 36%). Compared with LAC assays, the sensitivity of ACA-ELISA was high (greater than or equal to 77%), but specificity (less than or equal to 51%) and detection rate (less than or equal to 52%) were low. So, a panel of three LAC assays (PTT-HB, PL dilution, and KCT) can identify lupus patients apparently at risk for thrombosis, fetal loss, and/or thrombocytopenia, whereas the ACA-ELISA is insufficiently specific.  相似文献   
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OBJECTIVE: To study prospectively the effect of treatment with cyclophosphamide pulses (CYC) or azathioprine with methylprednisolone (AZA), both for 24-month periods, on health-related quality of life (HRQOL) in patients with proliferative lupus nephritis (LN) in a randomized controlled trial. We expected better HRQOL during AZA treatment. METHODS: HRQOL and disease activity were measured at start and after 12 and 24 months. Generic questionnaires [patient's visual analog scale (VAS), Medical Outcomes Study Short Form-36 Health Survey (SF-36), Profile of Mood States] and a disease-specific measure [Systemic Lupus Erythematosus (SLE) Symptom Checklist] were used. Treatment burden was assessed at 24 months. Disease activity was measured with the SLE Disease Activity Index (SLEDAI) and physician's VAS. RESULTS: Complete questionnaire data were available from 47 of the 87 patients included in the trial. These patients were representative of the whole group, except that completers were more often Caucasian. HRQOL scores improved significantly during treatment, particularly during the first year, on both generic and disease-specific outcomes. No statistically significant differences were found in HRQOL between the CYC and AZA groups, except for the SF-36 mental component summary scale, which showed more favorable scores in the AZA group. The mean reported treatment burden at 24 months was significantly higher in the CYC group. HRQOL scores did not correlate with the SLEDAI and physician's VAS. The disease activity measures correlated positively with each other. CONCLUSION: Treatment of patients with proliferative LN with immunosuppressive drugs and corticosteroids improves HRQOL, particularly in the first year. Due to the small groups studied, the absence of differences between AZA and CYC for most HRQOL scales should be interpreted cautiously: our data suggest that there may be no significant differences. Differences were a higher perceived treatment burden and worse mental HRQOL in the CYC group.  相似文献   
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Mastomys is a rodent with a high incidence of spontaneous carcinoids in the acid-producing part of the stomach. The present study was conducted to examine whether hypergastrinemia could promote tumor formation in this species. Mastomys, 4 months of age, were treated for 5 months with omeprazole subcutaneously, 100 mumol/kg body weight daily, and compared with mastomys given the vehicle only. The plasma gastrin concentration and the number of antral gastrin cells were increased in the omeprazole-treated group. The hypergastrinemia was associated with elevated histidine decarboxylase activity and histamine content in the oxyntic mucosa and with a trophic effect on the oxyntic mucosa and the enterochromaffin-like cells. However, no carcinoid tumors were observed, possibly because the strain of mastomys studied does not produce carcinoids spontaneously.  相似文献   
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Clinical consequences of antiphospholipid antibodies   总被引:1,自引:0,他引:1  
Antiphospholipid antibodies (aPL), notably the lupus anticoagulant and anticardiolipin antibodies, are the serological hallmarks of the antiphospholipid syndrome. Thrombosis and pregnancy complications are the most prominent clinical manifestations of this syndrome. This paper provides the clinician with guidelines for ordering and interpreting tests for aPL and discusses consequences for treatment if persistently positive tests are found.  相似文献   
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Background and objectives: No studies have evaluated the relationship among spirituality, social support, and survival in patients with ESRD. This study assessed whether spirituality was an independent predictor of survival in dialysis patients with ESRD after controlling for age, diabetes, albumin, and social support.Design, setting, participants, & measurements: A total of 166 patients who had ESRD and were treated with hemodialysis completed questionnaires on psychosocial variables, quality of life, and religious and spiritual beliefs. The religious variables were categorized into three scores on a 0 to 20 scale (low to high levels): Spirituality, religious involvement, and religion as coping. Social support was assessed using the Multidimensional Scale for Perceived Social Support. Analyses were also performed including and excluding patients with HIV infection. Religious variables were categorized on the basis of means, medians, and tertiles.Results: In analyses that used religious variables, only the responses on the spirituality scale split at the mean were associated with survival. The association of other religious variables with survival did not reach significance. Social support correlated with spirituality, religion as coping, and religious involvement measures. Only social support and age were associated with survival when controlling for diabetes, albumin concentration, HIV infection, and spirituality.Conclusions: These data suggest that the effects of spirituality may be mediated by social support. Larger, multicenter, prospective studies that use well-validated tools to measure religiosity and spirituality are needed to determine whether there is an independent association of spirituality variables with survival in patients with ESRD.Relationships between spirituality and mortality have been investigated in medical populations but remain controversial (113). Variable associations have been found depending on definitions of spirituality and patient populations studied (111). Miller and Thoreson (12) explored nine different hypotheses regarding the relationship among religious beliefs, spirituality, and mortality. The only hypothesis that they found to be supported by persuasive evidence stated that “church/service attendance protects [only] healthy people against death.” Studies supporting a similar link in patients with chronic illnesses have also shown mixed results. Koenig et al. (14) evaluated approximately 4000 elderly patients to determine whether attendance at religious services during a 6-yr period was associated with survival. In adjusted analyses, there was a significantly lower mortality in patients who frequently attended church services.Many researchers have suggested a publication bias, whereby only the studies that indicate a significant relationship are published (13). Most studies cited the need for more research on the relationship between spirituality and mortality before any firm conclusions can be reached. In addition, the health dimensions of lack of belief have not been well explored.There also exists considerable debate on how to operationalize religiosity and spirituality. Whereas the first term often is associated with participation in social institutions and adherence to specific beliefs and practices, the latter is a broader term that typically pertains to life''s vital qualities and an overall broad belief in the immaterial features of life (12). Spirituality relates to transcendent values and relationships and the way people find meaning, purpose, and hope in life and in the midst of suffering (15). A person may be spiritual and not religiously observant or observe rituals without a spiritual focus.Few studies have specifically evaluated the potential association between spirituality and survival in patients with ESRD (16,17). We (18) previously showed that religious and spiritual beliefs are associated with decreased perception of burden of illness, decreased depressive affect, increased perception of social support, and higher satisfaction with life and perception of quality of life in an urban, predominantly black ESRD population. We also found that a “spiritual beliefs scale” correlated with several quality-of-life measures in patients with ESRD (19). Even though many of these psychosocial measures have been shown to be related to survival independently, no study to our knowledge has demonstrated a link between spirituality and survival in this population.We determined whether three variables related to spirituality, religious beliefs, and practices and faith (spirituality, religious involvement, and religion as a coping measure) were independently associated with survival in hemodialysis patients with ESRD. We then assessed the relationship between social support and survival, regardless of whether the spiritual variables were included in analyses. We hypothesized that spiritual variables would be associated with survival in patients with ESRD.  相似文献   
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