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61.
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BackgroundBone quality and other preoperative predictive factors may affect implant migration and the survival of knee arthroplasty.MethodsIn a prospective cohort of 100 consecutive patients (65 women) at a mean age of 67.7 years (range 39-87 years), we investigated preoperative predictors of postoperative tibial component migration in cemented and cementless total knee arthroplasties or cemented unicompartmental knee arthroplasty. Predictors consisted of Knee Injury and Osteoarthritis Outcome Score (KOOS) and Oxford Knee Score, questionnaires, bone turnover markers of CTX and P1NP, systemic bone mineral density (BMD), and knee osteoarthritis (OA) grade. Tibial component migration was measured with radiostereometry postoperative, at 1 and 2 years of follow-up.ResultsBetween 1 and 2 years, 19 tibial components migrated continuously (maximum total point motion [MTPM] > 0.2 mm). In general, there was no difference in age, body mass index, BMD, KOOSs, or OA grade between patients with continuous tibial migration compared to patients without continuous migration (P > .11). However, cementless tibial components with continuous migration had a lower KOOS pain score (more pain), lower vitamin D, and a higher bone turnover (CTX) value than patients without continuous migration. There was no association between the BMD and MTPM at 1-year follow-up regardless of prothesis type (P > .17). Patients with osteoporosis and normal BMD had similar mean tibial component MTPM at 2 years (3 prostheses combined; P = .34).ConclusionMigration of tibial components inserted with or without bone cement was not affected by the preoperative bone quality in terms of systemic BMD, bone turnover markers, and OA grade in the knee.  相似文献   
63.
Atrial fibrillation is a growing health problem and the most common cardiac arrhythmia, affecting 5% of persons above the age of 65 years. The number of hospital discharges for atrial fibrillation has more than doubled in the past decade. It occurs very often in patients with congestive heart failure and the prevalence increases with the severity of the disease. These two conditions seem to be linked together, and congestive heart failure may either be the cause or the consequence of atrial fibrillation. The prognosis of atrial fibrillation is controversial, but studies indicate that atrial fibrillation is a risk factor in congestive heart failure patients. In the last 10-15 years, significant advances in the treatment of heart failure have improved survival, whereas effective management of atrial fibrillation in heart failure patients still awaits similar progress. Empirically, two strategies have evolved for treatment of atrial fibrillation: 1) rhythm control, which means conversion to sinus rhythm and maintenance of sinus rhythm; and 2) rate control, which means reduction of heart rate to an acceptable frequency. It is unknown whether one of these strategies is better than the other. In this review the authors discuss the prevalence, impact, and treatment of atrial fibrillation in heart failure patients.  相似文献   
64.
Fifteen to 50% of fetal deaths remain unexplained after post‐mortem examination depending on inclusion criteria and classification systems. Our aim was to examine a selection of unexplained fetal deaths in order to investigate whether any common chromosome aberrations or viral infections were present. Reports from 351 fetal autopsies performed at the Department of Pathology and Medical Genetics at St. Olavs University Hospital from 2001 through 2010 were reviewed. Of these, 105 fetal deaths were classified as unexplained. Tissue samples from 30 cases were further examined with fluorescence in situ hybridization (FISH) to detect abnormalities in chromosomes 13, 18, and 21. The samples were also examined with immunohistochemistry (IHC) and polymerase chain reaction (PCR) to detect infections with cytomegalovirus, parvovirus B19, herpes simplex virus 1 and 2, enterovirus, and parechovirus. In two cases, a possible trisomy 13 mosaicism was found. No viruses were detected. In our selection of 30 unexplained cases, possible trisomy 13 mosaicism was found in two cases, and no viruses were detected. High degree of maceration and missing placental examination often complicate the investigation of fetal death, and extensive ancillary examinations do not necessarily contribute to a more specific diagnosis.  相似文献   
65.

Background  

The main objective of this study was to describe the patients who were hospitalised at Oslo University Hospital Aker during the first wave of pandemic Influenza A (H1N1) in Norway.  相似文献   
66.
Chemosensory function, burning sensations in the tongue (BST), halitosis, saliva secretion, and oral health‐related quality of life (OHRQoL) were investigated in patients with primary Sjögren's syndrome (pSS). In 31 patients with pSS and 33 controls, olfactory and gustatory functions were evaluated. Self‐reported complaints of dysgeusia, BST, and halitosis were recorded. Saliva secretion rates were measured and OHRQoL was assessed using the short‐form Oral Health Impact Profile (OHIP‐14). Patients had significantly lower olfactory (8.8 ± 3.5 vs. 10.7 ± 1.2) and gustatory (18.9 ± 7.1 vs. 25.4 ± 4.3) scores than controls, and significantly more patients complained of dysgeusia (58.1% vs. 0%), BST (54.8% vs. 6.1%), and halitosis (41.9% vs. 0%). A significantly greater proportion of patients with pSS had ageusia (19% vs. 0%), hypogeusia (32% vs. 12%), anosmia (13% vs. 0%), or hyposmia (29% vs. 9%). Significantly lower saliva secretion rates (ml min?1) were observed in patients with pSS for stimulated (0.62 ± 0.40 vs. 1.57 ± 0.71) and unstimulated (0.08 ± 0.07 vs. 0.29 ± 0.17) saliva. The mean OHIP‐14 score was significantly higher in patients with pSS (16.2 ± 10.8 vs. 2.7 ± 3.1) and was positively correlated with dysgeusia, BST, and halitosis. In conclusion, patients with pSS reported higher occurrence of dysgeusia, BST, and halitosis, and demonstrated relatively impaired chemosensory and salivary functions. The patients’ poorer OHRQoL was associated with dysgeusia, BST, and halitosis.  相似文献   
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A number of clinically important drugs such as the epipodophyllotoxins etoposide (VP-16) and teniposide (VM-26), the anthracyclines daunorubicin and doxorubicin (Adriamycin), and the aminoacridine amsacrine exert their cytotoxic action by stabilizing the cleavable complex formed between DNA and the nuclear enzyme topoisomerase II. We have previously demonstrated in several in vitro assays that the anthracycline aclarubicin (aclacinomycin A) inhibits cleavable-complex formation and thus antagonizes the action of drugs such as VP-16 and daunorubicin. The present study was performed to validate these in vitro data in an in vivo model. At nontoxic doses of 6 and 9 mg/kg, aclarubicin yielded a marked increase in the survival of non-tumor-bearing mice given high doses of VP-16 (80–90 mg/kg) in six separate experiments. In therapy experiments on mice inoculated with Ehrlich ascites tumor cells, aclarubicin given at 6 mg/kg roughly halved the increase in median life span induced by VP-16 at doses ranging from 22 to 33 mg/kg. An attempt to determine a more favorable combination of VP-16 and aclarubicin by increasing VP-16 doses failed, as the two drugs were always less effective than VP-16 alone. The way in which VP-16-induced DNA strand breaks lead to cell death remains unknown. However, VP-16 has been reported to cause apoptosis (programmed cell death) in several cell lines. To ascertain whether the protection given by aclarubicin could have a disruptive effect on the apoptotic process, we used the small intestine as an in vivo model. Whereas VP-16-induced apoptosis in crypt stem cells was detectable at a dose as low as 1.25 mg/kg, aclarubicin given at up to 20 mg/kg did not cause apoptosis. Indeed, aclarubicin caused a statistically significant reduction in the number of cells rendered apoptotic by VP-16. The present study thus confirms the previous in vitro experiments and indicates the value of including an in vivo model in a preclinical evaluation of drug combinations.This work was supported by the Danish Cancer Society  相似文献   
70.
A series of novel 5-(4-piperidyl)-3-isoxazolol (4-PIOL) analogues where the 4-position of the 3-isoxazolol ring was substituted with groups of different size, flexibility, and lipophilicity have been characterised. Their activity as agonists and/or antagonists on human alpha(1)beta(2)gamma(2S) GABA(A) receptors expressed in Xenopus oocytes was studied using two-electrode voltage clamp electrophysiology. Methyl- and ethyl-substituted 4-PIOL analogues were characterised as partial agonists since weak agonist responses could be potentiated with lorazepam and inhibited by the competitive antagonist 2-(3-carboxypropyl)-3-amino-6-methoxyphenyl-pyradizinum bromide (SR95531). All larger substituents in the 4-position of the 3-isoxazolol ring of 4-PIOL converted the compounds into pure competitive antagonists. Additionally, for GABA, 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), piperidine-4-sulphonic acid (P4S), and 5-(4-piperidyl)-3-isothiazolol (thio-4-PIOL), a negative linear correlation was found between the agonist efficacy of the compound and the ability of lorazepam to potentiate EC(95) responses. Furthermore, a positive linear correlation between the lipophilicity of the substituents in the 4-position of the 3-isoxazolol ring of 4-PIOL and the antagonist affinity was found. These data suggest that the GABA(A) receptor contains a hydrophobic binding pocket at the GABA recognition site and that the binding of the 4-PIOL analogues is largely determined by the transfer from the aqueous phase to the hydrophobic pocket.  相似文献   
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