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81.
82.

Background and purpose

Previous national epidemiological data on the characteristics and trends of patients with ankle fractures have been limited. We therefore analyzed data on Swedish inpatients with ankle fractures in this nationwide population study, based on data from 1987 through 2004.

Patients and methods

Data on all inpatients aged 15 years and older with ankle fracture were extracted from the Swedish National Patient Register for the period 1987–2004.

Results

We identified 91,410 hospital admissions with ankle fracture, corresponding to an annual incidence rate of 71 per 105 person-years. During the study period, the number of hospital admissions increased by 0.2% annually, mainly from increase in fracture incidence in the elderly women. Mean age at admission was 45 (SD 19) years for men and 58 (18) for women. The major mechanism of injury was falling at the same level (64%).

Interpretation

This nationwide study of inpatients with ankle fractures showed an increase in fracture incidence, particularly in elderly women.Ankle fractures are among the most common fractures treated in orthopaedic surgery today. They are also a significant source of morbidity in both the young and the elderly (Donaldson et al. 1990, Jones et al. 1994, van Staa et al. 2001). Previous epidemiological studies have shown trends of increasing incidence over time, mainly in elderly women (Bengnér et al. 1986, Daly et al. 1987, Baron et al. 1996, Kannus et al. 1996, Court-Brown et al. 1998, van Staa et al. 2001, Kannus et al. 2002). However, most of these studies have included limited numbers of patients, and mostly originated from single hospitals or limited areas.Basic epidemiological data such as incidence, fracture type, age and sex distribution, mechanisms of injury, and surgical procedures can provide estimates when discussing disease burden and in the planning and provision of healthcare.The purpose of this study was to perform an epidemiological analysis of all adult ankle fractures requiring hospital admission in Sweden from 1997 through 2004, including incidence, causes of fracture, surgical procedures, patient characteristics, and trends over time.  相似文献   
83.

Background

Migraine attacks occur spontaneously in those who suffer from the condition, but migraine-like attacks can also be induced artificially by a number of substances. Previously published evidence makes the meninges a likely source of migraine related pain. This article investigates the effect of several vasodilators on meningeal arteries in order to find a connection between the effect of a substance on a meningeal vessel and its ability to artificially induce migraine.

Methods

A myograph setup was used to test the vasodilator properties of the substances acetylcholine (ACh), sodium nitroprusside (SNP), sildenafil, prostaglandin E2 (PGE2), pituitary adenylate cyclase activating peptide-38 (PACAP-38), calcitonin gene-related peptide (CGRP) and NaCl buffer on meningeal arteries from human and rat. An unpaired t-test was used to statistically compare the mean Emax(%) at the highest concentration of each substance to the Emax(%) of NaCl buffer.

Results

In the human experiments, all substances except PACAP-38 had an Emax (%) higher than the NaCl buffer, but the difference was only significant for SNP and CGRP. For the human samples, clinically tested antimigraine compounds (sumatriptan, telcagepant) were applied to the isolated arteries, and both induced a significant decrease of the effect of exogenously administrated CGRP. In experiments on rat middle meningeal arteries, pre-contracted with PGF, similar tendencies were seen. When the pre-contraction was switched to K+ in a separate series of experiments, CGRP and sildenafil significantly relaxed the arteries.

Conclusions

Still no definite answer can be given as to why pain is experienced during an attack of migraine. No clear correlation was found between the efficacy of a substance as a meningeal artery vasodilator in human and the ability to artificially induce migraine or the mechanism of action. Vasodilatation could be an essential trigger, but only in conjunction with other unknown factors. The vasculature of the meninges likely contributes to the propagation of the migrainal cascade of symptoms, but more research is needed before any conclusions can be drawn about the nature of this contribution.  相似文献   
84.
Busulphan and cyclophosphamide (Bu/CP) are widely used in preparative regimens for bone marrow transplantation. Many studies have shown a wide variation in busulphan pharmacokinetics. Moreover, higher rates of liver toxicity were reported in Bu/CP protocols than in a total body irradiation (TBI)-containing regimen. In the present paper we investigated the effect of the time interval between the last dose of busulphan and the first dose of cyclophosphamide on the pharmacokinetics of CP and its cytotoxic metabolite 4-hydroperoxycyclophosphamide (4-OHCP). Thirty-six patients undergoing bone marrow transplantation (BMT) were included in the study. We also investigated the occurrence of veno-occlusive disease, mucositis and graft-versus-host disease. Ten patients conditioned with CP followed by TBI served as a control group (TBI). Twenty-six patients were conditioned with Bu/CP. The patients received Bu (1 mg/kg x 4 for 4 days), followed by CP (60 mg/kg for 2 days) administered as a 1-h infusion. Patients received their CP therapy either 7-15 h (group A, n = 12) or 24-50 h (group B, n = 14) after the last dose of Bu. None of the patients were given phenytoin or any other drug known to enhance CP metabolism. The administration of CP less than 24 h after the last dose of Bu resulted in: (1) a significantly (P = 0.003) lower clearance for cyclophosphamide was observed in group A (0.036 l/h/kg) compared to 0.055 and 0.055 l/h/kg, in the B and TBI groups, respectively; (2) significantly (P = 0.002) longer elimination half-life in group A (10.93 h) than in groups B and TBI (6.87 and 7.52 h, respectively); (3) significantly (P < 0.001) lower exposure to the cytotoxic metabolite (4-OHCP), expressed as the ratio AUC4-OHCP/AUCCP, in group A (0.0053) than that obtained in group B (0.013) and group TBI (0.012); (4) the patients in group A had a significantly (P < 0.05) higher incidence of VOD (seven of 12) than the other groups, B and TBI (2/14 and 1/10, respectively); and (5) mucositis was significantly higher in group A patients (8/12), being seen in only one patient in group B and none in the TBI group. The present study has shown that the interval between busulphan and cyclophosphamide administration can negatively affect the pharmacokinetics of cyclophosphamide and its cytotoxic metabolite. We conclude that the timing of CP administration must be considered in order to improve drug efficacy and reduce conditioning-related toxicity.  相似文献   
85.
The purpose of this study was to examine the variability of 24-hour urinary and serum creatinine levels and creatinine clearance in normal subjects and to develop nomograms for assessing the adequacy of 24-hour urine collections. The data were from a longitudinal research program examining biochemical, hormonal, and hemodynamic parameters in normal subjects. Bloods and 24-hour urine specimens were collected at yearly intervals from 144 people over 9 years, and from an additional 110 over 4 years. The subjects were originally distributed equally by sex, race (black, white), blood pressure (three groups within the normal range), and age (three groups). Men had 33% higher urine creatinines per weight than females (P less than 0.001). Because they only had 8% higher creatinine clearance per weight they also exhibited 21% higher serum creatinine. Blacks had 5% higher urine creatinine per weight than whites, perhaps reflecting greater muscle mass, but their serum creatinines were not different from those of whites, reflecting a 5% higher creatinine clearance by weight than whites (P less than 0.01). Interestingly, older black men (age greater than 60 years) had 12% lower urine creatinine/weight than younger black men (P less than 0.001). They also had 13% lower creatinine clearance by weight, resulting in no net difference in serum creatinine. The intraindividual variability in urine creatinine excretion averaged 15% and did not differ between blacks and whites and men and women. The within individual variability in serum creatinine and creatinine clearance averaged 14 and 20%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
86.
Data on 49 allogeneic bone marrow transplant (BMT) recipients who developed interstitial pneumonia due to cytomegalovirus (CMV) were collected retrospectively. All patients were treated with ganciclovir and high doses of intravenous immune globulin, although types of immune globulins and schedules of treatment varied. Seventeen (35%) of 49 patients responded to treatment. Thirty days after the diagnosis of interstitial pneumonia, the survival rate among patients was 31%. CMV was detected in 81% of patients on whom autopsies were performed. The survival rate among patients who received total body irradiation (TBI) was significantly lower (11 [27%] of 41) than that among patients who did not receive TBI (six [75%] of eight; odds ratio = 12.3; P = .009). No other factor, including age, grade of graft-versus-host disease, types and dose of immune globulin used, or dose of ganciclovir, was correlated to survival. These results show that although survival of allogeneic BMT recipients with CMV interstitial pneumonia has improved, more than one-half of the patients still died of pneumonia. Thus, both prophylaxis for and treatment of CMV infection must be improved.  相似文献   
87.
BACKGROUND: Patients who receive bone marrow transplants have increased risk for new malignant conditions because of several risk factors, including conditioning with radiation and chemotherapy, immune stimulation, and malignant primary disease. The occurrence of and risk factors for malignant neoplasm in long-term survivors must be assessed. OBJECTIVE: To determine the risk and define potential risk factors for new malignant conditions in long-term survivors after marrow transplantation. DESIGN: Retrospective multicenter study. SETTING: Study of the Late Effects Working Party with 45 transplantation centers cooperating in the European Cooperative Group for Blood and Marrow Transplantation. PATIENTS: 1036 consecutive patients who underwent transplantation for leukemia, lymphoma, inborn diseases of the hematopoietic and immune systems, or severe aplastic anemia. Transplantation was done before December 1985, and patients had survived more than 5 years. MEASUREMENTS: Reports on malignant neoplasms were evaluated, and the incidence was compared to that in the general population. Patient age and sex, primary disease and status at transplantation, histocompatibility of the donor, conditioning regimen, type of prophylaxis of graft-versus-host disease, development of acute and chronic graft-versus-host disease, and treatment of chronic graft-versus-host disease were evaluated as variables. RESULTS: Median follow-up since transplantation was 10.7 years (range, 5 to 22.1 years). Malignant neoplasms were seen in 53 patients; the actuarial incidence (+/- SE) was 3.5% +/- 0.6% at 10 years and 12.8% +/- 2.6% at 15 years. The rate of new malignant disease was 3.8-fold higher than that in an age-matched control population (P < 0.001). The most frequent malignant diseases were neoplasms of the skin (14 patients), oral cavity (7 patients), uterus (including cervix) (5 patients), thyroid gland (5 patients), breast (4 patients), and glial tissue (3 patients). Median age of patients and their donors was 21 years. Malignant neoplasms were more frequent in older patients and in patients with chronic graft-versus-host disease. Older patient age and treatment of chronic graft-versus-host disease with cyclosporine were significant risk factors for new malignant neoplasms after bone marrow transplantation. CONCLUSIONS: The spectrum of neoplasms and immunosuppressive treatment with cyclosporine for chronic graft-versus-host disease as dominant risk factors indicate that immunosuppression is the major cause of malignant neoplasms in patients receiving marrow transplants.  相似文献   
88.
The Accreditation Sub-Committee of the EBMT regularly publishes special reports on current practice of haemopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders. Major changes have occurred since the last report in 1998. Haemopoietic stem cell transplantation today includes allogeneic and autologous stem cells derived from bone marrow, peripheral blood and cord blood. With reduced intensity conditioning regimens in allogeneic transplantation, the age limit has increased, permitting the inclusion of older patients. New indications have emerged, such as autoimmune disorders and AL amyloidosis for autologous, and solid tumours for allogeneic transplants. Other indications, such as autologous transplantation for breast cancer have been challenged. An updated report with revised tables and operating definitions is presented here.  相似文献   
89.
Leukocyte depletion (LD) by blood product filtration has been shown to be similarly effective to the use of screened, CMV seronegative blood products to prevent CMV disease in CMV seronegative allogeneic stem cell transplant (SCT) patients with CMV seronegative donors. The aim of this retrospective study was to determine the risk for development of CMV infection requiring preemptive therapy and for CMV disease if unscreened products treated by prestorage LD is used. Forty-nine consecutive patients transplanted after June 1995 were included. As a control group, 33 patients transplanted from January 1992 to June 1995 in whom a combination of CMV seronegative and LD blood products were given. All patients were monitored weekly by a leukocyte-based PCR for CMV DNA detection. Preemptive therapy was initiated after two consecutively positive tests. No patient developed CMV disease in either group. CMV DNA was detected in 6/49 (p = NS) in the study group and in 3/33 patients in the historical control group. Two patients in the study group were given preemptive therapy compared to one patient in the control group. This study suggests that the risk for CMV disease and the need for preemptive therapy against CMV is low in CMV seronegative allogeneic SCT patients receiving grafts from CMV seronegative stem cell donors receiving LD blood products. Thus, this strategy can be safely used together with PCR monitoring and preemptive therapy.  相似文献   
90.
Pretransplant herpes virus serology and chronic graft-versus-host disease   总被引:1,自引:0,他引:1  
The influence of pretransplant herpes virus antibodies in patients and donors in the subsequent development of chronic graft-versus-host disease (GVHD) was analysed in 150 consecutive HLA identical bone marrow recipients. The Cox regression bivariate analysis showed that (i) pretransplant seropositivity for cytomegalovirus (CMV) in the patients and the donors, (ii) donor seropositivity for herpes simplex virus and Epstein-Barr virus, (iii) high donor and patient age, (iv) a previous grade II-IV acute GVHD, (v) patients receiving unirradiated donor buffy coat cells post-transplant, (vi) overall CMV infection, (vii) high donor herpes virus load (positive serology for 3-4 herpes viruses versus 0-2), and (viii) high recipient herpes virus load prior to BMT were all associated with a high incidence of chronic GVHD. In Cox regression multivariate analysis, high pretransplant donor herpes virus load (p less than 0.001) and a previous grade II-IV acute GVHD (p = 0.02) were the strongest predictors of chronic GVHD. Thus, herpes virus immune cells in the donated marrow may play a role in the pathophysiology of chronic GVHD.  相似文献   
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