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91.
Instances of anterior knee pain and patellar fracture are significant complications following total knee replacement (TKR). Bone strain measured in the patella can provide an indication of patellar fracture risk and may also be related to anterior knee pain. The objective of this study was to develop subject‐specific finite element models of the patellofemoral (PF) joint including density‐mapped material properties to gain insight into the patellar bone strain distribution in the natural and implanted knee. In eight subjects, the volume of bone experiencing strains >0.5% in the implanted condition was ~200% larger, on average, than the natural condition. An inverse relationship with a correlation of ?0.74 was established between postoperative bone volume and strain in the implanted specimens, suggesting that patellar geometry may be a useful indicator of postoperative strain. Comparing strains between regions (superior, inferior, medial, and lateral), it was found that although highly strained bone was evenly distributed between medial and lateral regions in the natural case, the implanted specimens demonstrated significantly larger volumes of highly strained bone medially as a result of substantially lower modulus bone in the medial compartment. Understanding distributions of PF strain may aid in preoperative identification of those patients at risk for patellar fracture or anterior knee pain, guidance regarding altered component placement for at‐risk patients, and design of components considering the implications of PF load transfer and patellar strain distribution. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:232–239, 2011  相似文献   
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We present here an analysis of 888 unrelated beta-thal chromosomes consisting of 444 transfusion dependent children from various regions of Punjab and Islamabad Pakistan. By using Multiplex ARMS- PCR, restriction endonuclease analysis, allele specific oligonucleotide (ASO) hybridization and sequencing, 17 beta-thal mutations and 3 Hb variants were detected in 99.5 % (884/888) of the chromosomes analyzed. First trimester prenatal diagnosis by chorionic villus sampling (CVS) was also carried out in seven pregnancies at risk of beta-thalassemia. Our results indicate that three most common mutations accounted for 86.8% of the beta-thal alleles in this region. These findings have important implications for prevention of beta-thalassemia through genetic counseling and prenatal diagnosis in this part of Pakistan.  相似文献   
94.
A rare case of halothane-induced fulminant hepatic failure is reported in a 22 years old male, who developed fever, jaundice, coma and deranged coagulation profile, 2 days after undergoing laparotomy under halothane anaesthesia. Despite all supportive care, he died of fulminant hepatic failure, 6 days after surgery. Postmortem liver biopsy revealed massive predominantly centrilobular hepatic necrosis.  相似文献   
95.
Summary Background: LY293111 is an oral agent known to be a leukotriene B4 (LTB4) receptor antagonist and a 5-lipoxygenase inhibitor resulting in selective inhibition of the lipoxygenase pathway. Lipoxygenases metabolize arachidonic acid and have been involved in cancer cell proliferation and survival. In addition, LY293111 has been found to be a peroxisome proliferator activated receptor-gamma (PPAR-γ) agonist. Antineoplastic activity of LY293111 has been identified in preclinical models both alone and in combination with chemotherapy agents including irinotecan. The NCIC Clinical Trials Group studied LY293111 in combination with irinotecan to determine the recommended dose of the combination and to describe its tolerability and pharmacokinetic interaction. In addition the anti-tumour activity of LY293111 in combination with irinotecan was documented. Patients and methods: Twenty-eight patients with advanced solid tumours were treated on seven dose levels with the combination of irinotecan and LY293111. Irinotecan was administered intravenously every 21-days as a single dose. LY293111 was administered twice daily continuously by mouth. Results: Dose limiting toxicity (DLT) of grade 3 diarrhea was seen in two patients with doses of irinotecan 300 mg/m2 IV every 21-days in combination with LY293111 300 mg BID. Subsequently the dose of irinotecan was decreased to 250 mg/m2 IV every 21-days with escalating doses of LY293111. A DLT of grade 3 abdominal pain was seen at dose 600 mg BID of LY293111 with irinotecan 250 mg/m2. The pharmacokinetics (PK) indicated that the administration of LY293111 did not have an effect on the PK of irinotecan or its metabolite SN-38. No responses were seen; seven patients had stable disease of a median duration of 4.4 months (range 2.8–13 months). Conclusion: The recommended phase II dose of LY293111 is 600 mg orally BID in combination with irinotecan 250 mg/m2 IV every 21-days. Gastrointestinal adverse effects were common but could be well managed.  相似文献   
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97.
Abstract: Identifying indices of poor prognosis at first presentation after acetaminophen poisoning is the key to both improving clinical care and determining targets for intervention. This study intended to document the prevalence, clinical characteristics and predictors of vomiting and to investigate the relationship between episodes of vomiting at first hospital presentation and outcome in acetaminophen poisoning. This retrospective cohort study included patients who attended the emergency department and were admitted within 24 hr of acetaminophen ingestion. The study was conducted over a period of 5 years from 1 January 2004 to 31 December 2008. Parametric and non‐parametric tests were used to test differences between groups depending on the normality of the data. SPSS 15 was used for data analysis. Data from 291 patients were included. Vomiting was present in 65.3% of patients with acetaminophen poisoning at the time of first presentation. Multiple logistic regression showed that significant risk factors for vomiting were present among patients who reported an ingested dose of acetaminophen ≥10 g (p < 0.001) and a latency time of more than 8 hr (p = 0.030). Overall, an increasing trend in prothrombin time (p = 0.03), serum bilirubin (p < 0.001), serum creatinine (p = 0.005), serum potassium (p < 0.001), length of hospital stay (p < 0.001) and the prevalence of patients who had a serum acetaminophen level above a ‘possible toxicity’ treatment line (p = 0.001) were associated with an increased number of episodes of vomiting. In conclusion, vomiting was common among patients with acetaminophen poisoning. This study suggests that an increase in episodes of vomiting at first presentation appears to be an important risk marker of subsequent nephrotoxicity and hepatotoxicity.  相似文献   
98.
The number of cases of neurological disease is expected to rise in the next 10 years, making this the second leading cause of morbidity and mortality after heart disease in Malaysia. The lack of human resources in the neurological field currently serving the Malaysian population may cause a deficiency in specialized care, especially in rural areas where neurological and neurosurgical care may be lacking. Thus, a resolve was made to increase the numbers of specialists by the Universiti Sains Malaysia (USM) with the help of the Ministry of Health of Malaysia. A study was made to evaluate the number of referral centers needed in strategic parts of Malaysia. Our calculation was based on service demands and operative procedures following the guidelines of the Association of British Neurologists (ABN) where 15 minutes of service time was equivalent to 1 unit. Based on 2 million population covered in the state of Kelantan by this University Hospital, 4.27 neurologists are needed to meet service demands with a consultant to population ratio (CPR) of 1:468,384, compared to 7.46 neurosurgeons, with a CPR of 1:268,097. According to the current service demands, one neurologist has to work more than 407 hours per year and one neurosurgeon 1,219 hours per year in our hospital. Hospitals with a larger catchment area would need to have more neurologists and neurosurgeons for optimal care in their area. Thus, more neurologists and neurosurgeons are needed to be produced, since the existing numbers are too small for quality care in Malaysia.  相似文献   
99.
100.
Isoalantolactone, a sesquiterpene lactone, possesses anti-fungal as well as cytotoxic properties. In this study, the effects of Isoalantolactone on cell viability, cell cycle, and apoptosis were investigated in human gastric adenocarcinoma SGC-7901 cells. The results demonstrated that Isoalantolactone induced morphological changes and decreased cell viability. Subsequently, we found that Isoalantolactone induced G2/M and S phase arrest, which was associated with a decrease in the expression level of cyclin B1. Apoptosis triggered by Isoalantolactone was visualized using propidium iodide (PI) and Annexin V-FITC/PI staining. Isoalantolactone-induced apoptosis of SGC-7901 cells was associated with the dissipation of mitochondrial membrane potential (ΔΨ m) that was due to the down-regulation of Bcl-2 and up-regulation of Bax that led to the cleavage of caspase-3. Additionally, it was found that Isoalantolactone was involved in the inhibition of phosphorylation of PI3K/Akt. Isoalantolactone-induced cytotoxicity and apoptosis of SGC-7901 cells involve mitochondria-caspase and PI3K/Akt dependent pathways, which gives the rationale for in vivo studies on the utilization of Isoalantolactone as a potential cancer therapeutic compound.  相似文献   
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