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41.
OBJECTIVE: To assess the relative contribution of constitutional (individual) factors, pre-accident health, psychological and workplace psychosocial factors, and accident related (mechanical) factors in the development of neck pain (whiplash) following a motor vehicle accident. METHODS: We conducted a case-control study of drivers (ages 17-70 yrs) who reported a motor vehicle accident to their insurance company. A self-report mailed questionnaire retrospectively collected information on the driver's pre- and post-accident health, details of the accident, and other exposure data. Case/control status (post-accident neck pain) was ascertained using a preshaded manikin. RESULTS: In total, 26% of drivers reported post-accident neck pain. Women, younger individuals, and those with a history of neck pain were more likely to report neck pain following their accident (OR 1.50, 95% CI 0.98, 2.28; OR 1.62, 95% CI 0.96, 2.74; OR 1.75, 95% CI 1.09, 2.81, respectively). In addition, a number of accident related and psychosocial factors were independently associated with reporting post-accident neck pain: collision from behind (OR 2.55, 95% CI 1.41, 4.62); vehicle stationary at impact (OR 1.93, 95% CI 1.12, 3.33); collision severity (upper vs lowest tertile: OR 16.1, 95% CI 8.64, 30.1); not being at fault (OR 2.61, 95% CI 1.49, 4.59); and monotonous work (OR 2.19, 95% CI 1.19, 4.04). Based on these 8 factors, the likelihood of having neck pain increased from 7% with < or = 2 risk factors to 62% with > or = 5. CONCLUSION: Development of neck pain after a motor vehicle accident is a complex phenomenon resulting from the combined effects of constitutional, mechanical, and psychosocial factors. Using 8 such variables it is possible to identify those at high risk of developing neck pain. 相似文献
42.
43.
Clonal dysregulation of the antibody response to tetanus-toxoid after bone marrow transplantation 总被引:2,自引:0,他引:2
Gerritsen EJ; Van Tol MJ; Van 't Veer MB; Wels JM; Khouw IM; Touw CR; Jol-Van Der Zijde CM; Hermans J; Rumke HC; Radl J 《Blood》1994,84(12):4374-4382
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers. 相似文献
44.
Recombinant human interleukin-11 stimulates multilineage hematopoietic recovery in mice after a myelosuppressive regimen of sublethal irradiation and carboplatin 总被引:23,自引:3,他引:23
Interleukin-11 (IL-11) is a novel multifunctional hematopoietic cytokine capable of stimulating cells of the myeloid, lymphoid, erythroid, and megakaryocytic lineages in vitro. We have tested the pleiotropic properties of this cytokine on the hematopoietic recovery of mice after a combined regimen of sublethal irradiation and carboplatin administration. This regimen results in severe myelosuppression, characterized by a prolonged period of thrombocytopenia and severe anemia. Administration of recombinant human IL-11 (rhIL-11; 250 micrograms/kg/d) had multilineage effects on bone marrow and spleen hematopoietic activity, increasing the number of megakaryocyte, erythroid, granulocyte, and macrophage progenitors compared with the vehicle-treated controls. This was reflected in the peripheral circulation by a reduction of both the platelet and hematocrit nadirs and a significantly reduced period of thrombocytopenia and anemia in the rhIL-11-treated mice. The results from this study support the broad spectrum of biologic activities that have been attributed to rhIL-11 in vitro and suggest that this cytokine may be an effective agent in the treatment of myelosuppression associated with cancer chemotherapy and bone marrow transplantation. 相似文献
45.
Abnormal function of the bone marrow microenvironment in chronic myelogenous leukemia: role of malignant stromal macrophages 总被引:7,自引:4,他引:7
The bone marrow microenvironment supports and regulates the proliferation and differentiation of hematopoietic cells. Dysregulated hematopoiesis in chronic myelogenous leukemia (CML) is caused, at least in part, by abnormalities in CML hematopoietic progenitors leading to altered interactions with the marrow microenvironment. The role of the microenvironment itself in CML has not been well characterized. We examined the capacity of CML stroma to support the growth of long-term culture-initiating cells (LTC-IC) obtained from normal and CML marrow. The growth of normal LTC-IC on CML stroma was significantly reduced compared with normal stroma. This did not appear to be related to abnormal production of soluble factors by CML stroma because normal LTC- IC grew equally well in Transwells above CML stroma as in Transwells above normal stroma. In addition, CML and normal stromal supernatants contained similar quantities of both growth-stimulatory (granulocyte colony-stimulating factor (CSF), interleukin-6, stem cell factor, granulocyte-macrophage CSF, and interleukin-1 beta) and growth- inhibitory cytokines (transforming growth factor-beta, macrophage inflammatory protein-1 alpha, and tumor necrosis factor-alpha). The relative proportion of different cell types in CML and normal stroma was similar. However, polymerase chain reaction and fluorescence in situ hybridization studies showed the presence of bcr-abl-positivo cells in CML stroma, which were CD14+ stromal macrophages. To assess the effect of these malignant macrophages on stromal function, CML and normal stromal cells were separated by fluorescence-activated cell sorting into stromal mesenchymal cell (CD14-) and macrophage (CD14+) populations. CML and normal CD14- cells supported the growth of normal LTC-IC equally well. However, the addition of CML macrophages to normal or CML CD14- mesenchymal cells resulted in impaired progenitor support. This finding indicates that the abnormal function of CML bone marrow stroma is related to the presence of malignant macrophages. In contrast to normal LTC-IC, the growth of CML LTC-IC on allogeneic CML stromal layers was not impaired and was significantly better than that of normal LTC-IC cocultured with the same CML stromal layers. These studies demonstrate that, in addition to abnormalities in CML progenitors themselves, abnormalities in the CML marrow microenvironment related to the presence of malignant stromal macrophages may contribute to the selective expansion of leukemic progenitors and suppression of normal hematopoiesis in CML. 相似文献
46.
ObjectiveThis meta-evaluation aimed to summarize all available evidence regarding different fissure sealants on occlusal caries prevention, arrest, retention rate, adverse effect, and cost-effectiveness; when compared with no intervention, other preventive or minimally-invasive procedures.Materials and MethodsThe systematic reviews and meta-analyses were identified via four electronic databases and manual searching. Two independent reviewers performed study selection, data extraction, quality assessment with AMSTAR-2.ResultsAmong the 366 records yielded, 38 systematic reviews were identified as eligible 24 of them included meta-analyses. Moderate evidence has supported the efficacies of resin-based sealants (RBS) in occlusal caries prevention, arrest and cost-effectiveness compared to no interventions. Low to very low certainty of evidence suggested similar effectiveness of glass-ionomer cements in caries prevention with RBS and more superior performance of resin infiltration in arresting non-cavitated occlusal lesions.ConclusionThis meta-evaluation supports the use of RBS on permanent molars to reduce occlusal caries occurrence, arrest lesion progression and alleviate oral health inequalities between individuals of different socioeconomic status. This meta-evaluation also advocates further research on glass-ionomer cements and resin infiltration with respect to their efficacies in caries prevention and arrest. 相似文献
47.
Simon W. Young Tim Roberts Sarah Johnson James P. Dalton Brendan Coleman Siouxsie Wiles 《Clinical orthopaedics and related research》2015,473(11):3573-3584
Background
In human TKA studies, intraosseous regional administration (IORA) of prophylactic antibiotics achieves local tissue antibiotic concentrations 10 times greater than systemic administration. However, it is unclear if such high concentrations provide more effective prophylaxis.Questions/purposes
We asked: (1) What prophylaxis dosage and route (intravenous [IV] versus IORA of prophylactic antibiotics) produce less in vivo bacterial burden compared with no-antibiotic controls? (2) Compared with controls, what prophylaxis dosage and route yield fewer colony-forming units (CFUs) in euthanized animals in a model of TKA? (3) Is prophylactic IORA of antibiotics more effective than same-dose IV antibiotic administration in reducing CFUs?Methods
Mice (six to nine per group) were block randomized to one of six prophylaxis regimens: control, systemic cefazolin (C100IV), IORA of cefazolin (C100IORA), systemic vancomycin (V110IV), low-dose systemic vancomycin (V25IV), and low-dose IORA of vancomycin (V25IORA). Surgery involved placement of an intraarticular knee prosthesis, followed by an inoculum of bioluminescent Staphylococcus aureus strain Xen36. Biophotonic imaging assessed in vivo bacterial loads, and after 4 days bacterial load was quantified using culture-based techniques. Comparisons were made for each prophylactic regimen to controls and between same-dose IV and IORA of prophylactic antibiotic regimens.Results
Mice treated with systemic high-dose vancomycin, IORA of vancomycin, or IORA of cefazolin had lower in vivo Staphylococcus aureus burdens (median area under curve, Control: 5.0 × 106; V110IV: 1.5 × 106, difference of medians 3.5 × 106, p = 0.003; V25IV: 1.94 × 106, difference 3.07 × 106, p = 0.49; V25IORA: 1.51 × 106, difference 3.5 × 106, p = 0.0011; C100IORA: 1.55 × 106, difference 3.46 × 106, p = 0.0016; C100IV: 2.35 × 106, difference 2.66 × 106, p = 0.23.) Similar findings were seen with culture-based techniques on recovered implants. IORA of prophylactic antibiotics was more effective than same-dose IV administration in reducing bacterial load on recovered implants (median CFUs < 7.0 × 100 vs 2.83 × 102, p = 0.0183).Conclusions
IORA of prophylactic cefazolin and vancomycin was more effective than the same dose of antibiotic given systemically. The effectiveness of vancomycin in particular was enhanced by IORA of prophylactic antibiotics despite using a lower dose.Clinical relevance
Our study supports previous studies of IORA of prophylactic antibiotics in humans and suggests this novel form of administration has the potential to enhance the effectiveness of prophylaxis in TKA. Because of concerns regarding antibiotic stewardship, IORA of prophylactic vancomycin may be more appropriately restricted to patients having TKA who are at greater risk of infection, and clinical trials are in progress. 相似文献48.
Immunosuppressive treatment for myocarditis and borderline myocarditis in children with ventricular ectopic rhythm. 下载免费PDF全文
OBJECTIVES--To ascertain the responsiveness to immunosuppressive treatment of myocarditis and borderline myocarditis in children with ventricular ectopic rhythm (that is, all ventricular arrhythmia except benign premature ventricular contractions). To determine the impact of the diagnostic information provided by an endomyocardial biopsy specimen in these patients. BACKGROUND--The therapeutic value of performing an endomyocardial biopsy in children with ventricular ectopic rhythm is not established. In turn, the treatment of myocarditis with immunosuppressive drugs is also controversial. METHODS--The case notes and endomyocardial biopsy findings of all children with ventricular ectopic rhythm and a biopsy diagnosis of myocarditis were reviewed. RESULTS--Ten (14%) of 69 patients with ventricular ectopic rhythm and an anatomically normal heart had histological evidence of myocarditis or borderline myocarditis. Eight patients received corticosteroids and efficacy was judged by regular 24 hour Holter monitoring. Total resolution of arrhythmia was seen in four, improvement in two, and no change in two patients. At follow up (8-39 months, mean 22 months), arrhythmia recurrence was seen in the two patients who showed an improvement but not resolution during treatment. Both received azathioprine with further reduction in ectopy rates. Patients who responded to treatment were symptomatic (six of six patients) at presentation compared with those who did not respond to treatment (none of two patients) who were not symptomatic. Five patients had a repeat biopsy specimen taken which confirmed histological improvement. CONCLUSIONS--Steroid treatment seems to benefit a subset of children with ventricular ectopic rhythm and a biopsy diagnosis of myocarditis or borderline myocarditis. Because it can identify a treatable cause for the ventricular arrhythmia, endomyocardial biopsy is a valuable investigation in these patients. 相似文献
49.
Dr. Mary Fanning MD PhD FRCP Marc Monte MD Lloyd R. Sutherland MDCM FRCPC FACP MSc Mary Broadhead RN ONC Gerard F. Murphy MD CM MSc Alan G. Harris MD 《Digestive diseases and sciences》1991,36(4):476-480
Seventeen AIDS patients were enrolled in a prospective open-label dose-finding study of octreotide (Sandostatin) therapy for refractory diarrhea. Five were nonevaluable due to progression of AIDS symptomatology, and one was excluded because of lack of confirmation of HIV infection. Five of 11 evaluable patients responded to therapy (45%); two each at 50 g and 100 g, and one at 250 g thrice daily doses. A sixth patient demonstrated a moderate reduction in stool volume at 250 g thrice daily, which, although deemed clinically relevant, did not meet the criteria for response. On discontinuation of therapy, diarrhea recurred in all patients within 1–12 days, and responded to reinitiation of octreotide in those five patients who resumed treatment. Only one of the three patients with concurrent cryptosporidial infection responded to treatment. The drug was well tolerated, with mild symptomatology in three patients. Long-term treatment at a stable dose was effective in three of five treated patients for periods for seven months in one (moderate responder) and one year in two. One patient required dose increases to control symptoms, but after one year of treatment developed severe nausea following injections, which required dose cessation. One patient had partial control of his diarrhea for only three months despite two dose increases. These data suggest that octreotide may be of useful therapeutic value in HIV-associated diarrhea and that further studies are indicated.This study was supported by Sandoz Canada Inc. 相似文献
50.
Nicola Diviani Bas van den Putte Stefano Giani Julia CM van Weert 《Journal of medical Internet research》2015,17(5)