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91.

Background  

Osteoarthritis (OA) involves changes in both bone and cartilage. These processes might be associated under some circumstances. This study investigated correlations between bone and cartilage degradation in patients with OA as a function of sex, Kellgren-Lawrence (KL) score, Body Mass Index (BMI), oral salmon calcitonin (sCT) treatment and diurnal variation.  相似文献   
92.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
93.
AJ Vyse  BJ Cohen  ME Ramsay 《Public health》2001,115(3):201-207
Three oral fluid collection devices (OraSure, Omni-SAL and Oracol) were compared in terms of the quality of oral fluid collected by each device for antibody testing and their acceptability to participants. Participants (143 children aged 3.5-5 y from North Hertfordshire, UK, who had recently received DTaP and MMR vaccination) were randomised to use one of the three types of collection device. Oral fluid was collected by a parent who completed a short questionaire recording information on ease of use and willingness to use the device again. A matching serum sample was collected by a nurse. Oral fluid samples were screened for total IgG and IgM by ELISA and for rubella specific IgG and parvovirus specific IgG by radioimmunoassay. Serum samples were screened for rubella specific IgG and parvovirus B19 specific IgG by ELISA. 87.4% (125) of participants provided a matching oral fluid and serum sample. Of these, 100% (125) and 10.4% (13) had serum IgG specific for rubella and parvovirus B19, respectively. The Oracol device provided oral fluid samples with the highest geometric mean titres of total IgG and IgM and with rubella specific IgG results which correlated most closely with those of matching sera. A higher proportion of parents found the Oracol and OraSure devices easier to use than the Omni-SAL (P<0.001) and the proportion who would not take another test was higher for the Omni-SAL than for the Oracol or Orasure. Oral fluid samples collected by each of the devices gave qualitative results acceptable for surveillance and epidemiological studies of rubella and parvovirus B19. The highest quality oral fluid sample for antibody testing in terms of total IgG and IgM concentration and rubella specific IgG concentration was collected by the Oracol. The acceptability to participants of both the Oracol and OraSure was high. As the cheapest device available, the Oracol is the preferred oral fluid collection device for studies involving children in the UK.  相似文献   
94.
95.
患者为1例39岁女性,患T/NK细胞淋巴瘤,在外周血异基因干细胞移植后15天,发生环孢素A(CSA)毒性相关的微血管病溶血性贫血(MAHA).因血清肌酐从移植前的0.4mg/dL,上升至移植后第9和15天的1.0和2.9 mg/dL.故停用CSA.  相似文献   
96.
97.
Recombinant thrombopoietin has been reported to stimulate megakaryocytopoiesis and thrombopoiesis and it may be quite useful to treat patients with low platelet counts after chemotherapy. As little is known regarding the possible activation of platelets by thrombopoietin, we examined the effects of thrombopoietin on platelet aggregation induced by shear stress and various agonists in native plasma. Using hirudin as an anticoagulant, thrombopoietin (1 to 100 ng/mL) enhanced platelet aggregation induced by 2 micromol/L adenosine- diphosphate (ADP) in a dose dependent fashion. The enhancement was not affected by treatment of platelets with 1 mmol/L aspirin plus SQ-29548 (a thromboxane antagonist, 1 micromol/L) but was inhibited by a soluble form of the thrombopoietin receptor, suggesting that the enhancement was mediated by the specific receptors and does not require thromboxane production. Epinephrine (1 micromol/L), which does not induce platelet aggregation in hirudin platelet rich plasma (PRP), did so in the presence of thrombopoietin (10 ng/mL). Thrombopoietin (10 ng/mL) also enhanced or primed platelet aggregation induced by collagen (0.5 micron.mL),. thrombin, serotonin, and vasopressin. Thrombopoietin does not induce any rise in cytosolic ionized calcium concentration nor activation of protein kinase C, as estimated by phosphorylation of preckstrin, indicating that the priming effects of thrombopoietin does not require those processes. The ADP- or thrombin-induced rise in cytosolic ionized calcium concentration was not enhanced by thrombopoietin (100 ng/mL). Further, shear (ca. 90 dyn/cm2)-induced platelet aggregation was also potentiated by thrombopoietin. The priming effect on epinephrine-induced platelet aggregation in hirudin PRP was unique to thrombopoietin, with no effects seen using interleukin-6 (IL-6), IL-11, IL-3, erythropoietin, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, or c-kit ligand. These data indicate that monitoring of platelet functions may be necessary in the clinical trials of thrombopoietin.  相似文献   
98.
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
99.
白花丹参化学成分的研究   总被引:30,自引:0,他引:30  
从白花丹参(Salvia miltiorrhiza f.alba)中分离出14个二萜醌类化合物,其中2个为新化合物,由光谱分析推定为1,2,15,16-四氢丹参醌(Ⅰ)和丹参醛(Ⅱ);另一个化合物Ⅲ与R0-090680的结构相同。化合物Ⅰ和Ⅲ对淋巴白血病细胞P388均有较强的抑制作用。  相似文献   
100.
Strand L, Jenkins A, Grude N, Allum A‐G, Mykland H‐C, Nowrouzian FL, Kristiansen B‐E. Emergence of fluoroquinolone‐resistant clonal group A: clonal analysis of Norwegian and Russian E. coli isolates. APMIS 2010; 118: 571–77. We describe a study of urinary tract and intestinal isolates of Escherichia coli from Norway and Russia using automated ribotyping, single nucleotide polymorphism analysis for clonal group A (CgA) supplemented with phylogrouping, virulence gene profiling and resistance profiling. CgA comprised 19% of the Norwegian UTI isolates from 2001. Two highly multiresistant fluoroquinolone‐resistant CgA isolates were found. Ribotypes clustered into four major and six minor groups (ribogroups). Fluoroquinolone‐resistant isolates and phylogroups A and B1 were associated with ribogroup RA. Ribogroup RB predominated among Russian UTI isolates and was predominantly phylogroup A and depleted in P‐fimbriae. Ribogroup RC predominated among Norwegian UTI isolates and was rich in virulence factors (S‐fimbriae, haemagglutinin and haemolysin) and predominantly phylogroup B2 and D. Ribogroup RG was associated with CgA and predominantly phylogroup D. Ribogroups RD, RE and RF had too few members for statistical analysis. The correlation between ribotype and phylogenetic group was not as strong as reported in other studies.  相似文献   
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