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81.
With the advent of computerized databases, medical data has become easy to accumulate; however, effective use of this data continues to pose significant problems. In other circumstances, smoothing algorithms have been used to uncover non-obvious correlations, trends and relationships in noisy data. We have applied four such algorithms to a large dataset of postoperative blood replacement in cardiopulmonary bypass patients. When applied to this dataset, one of the algorithms proved surprisingly effective. It confirmed several previously observed correlations, and also provided an additional series of counterintuitive and apparently unrelated associations. These associations have been explored in an accompanying paper. 相似文献
82.
Peter Angelos 《World journal of surgery》2009,33(4):609-611
83.
Kentaroh Miyoshi Minoru Naito Tsuyoshi Ueno Shinji Hato Hideo Ino 《General thoracic and cardiovascular surgery》2009,57(11):629-632
A benign esophageal leiomyoma with abnormally increased fluorine-18-fluorodeoxyglucose uptake on positron emission tomography
(PET) was resected thoracoscopically. The tumor, of which the maximum standardized uptake value of the lesion was 4.7, was
well defined and 38 mm in diameter. Neither mitotic activity nor degeneration was found histologically; and immunoreactivity
for CD34, CD117, MIB-1, and glucose transporter-1 was negative immunohistochemically. A diagnosis of gastrointestinal stromal
tumor was ruled out by an oncogenic kinase gene mutation study. This case cautions against PET-dependent evaluation for malignant
potential of esophageal submucosal tumors. 相似文献
84.
85.
Timothy M. Pawlik Kelly Olino Ana Luiza Gleisner Michael Torbenson Richard Schulick Michael A. Choti 《Journal of gastrointestinal surgery》2007,11(7):860-868
Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury
and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with
preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present,
was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who
underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on
demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority
of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and
oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns
of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin
(all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received
irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%)
and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases,
preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic
injury after preoperative chemotherapy was regimen-specific.
Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida. 相似文献
86.
Oren N Gottfried Steven Chin H Christian Davidson William T Couldwell 《Skull base》2007,17(5):317-324
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction. 相似文献
87.
Simon Bell Andrew J McLachlan Parisa Aslani Paula Whitehead Timothy F Chen 《Australia and New Zealand Health Policy》2005,2(1):29
The objective of this systematic review was to evaluate the impact of pharmacist delivered community-based services to optimise the use of medications for mental illness. Twenty-two controlled (randomised and non-randomised) studies of pharmacists' interventions in community and residential aged care settings identified in international scientific literature were included for review. Papers were assessed for study design, service recipient, country of origin, intervention type, number of participating pharmacists, methodological quality and outcome measurement. Three studies showed that pharmacists' medication counselling and treatment monitoring can improve adherence to antidepressant medications among those commencing treatment when calculated using an intention-to-treat analysis. Four trials demonstrated that pharmacist conducted medication reviews may reduce the number of potentially inappropriate medications prescribed to those at high risk of medication misadventure. The results of this review provide some evidence that pharmacists can contribute to optimising the use of medications for mental illness in the community setting. However, more well designed studies are needed to assess the impact of pharmacists as members of community mental health teams and as providers of comprehensive medicines information to people with schizophrenia and bipolar disorder 相似文献
88.
Statutory reimbursement agencies as well as private insurers throughout member states of the Organization for Economic Cooperation and Development (OECD) reimburse the cost of medicines on the basis of criteria that include robust clinical evidence, budget impact analysis, and incremental cost effectiveness. The Centers for Medicare and Medicaid Services (CMS) in the US are no exception to this rule and are, in principle, seeking to maximize benefit for their Medicare enrollees, whilst ensuring reasonable drug outlays for the small number of drugs that they reimburse. This paper provides a retrospective analysis of the way two functionally equivalent drugs are treated for reimbursement purposes by the CMS; the period under consideration was 2001–3. The two drugs, epoetin-α and darbepoetin-α, are used for the treatment of anemia in renal failure and in patients receiving chemotherapy. By reviewing the publicly available pharmacological and clinical data of epoetin-α and darbepoetin-α, the paper confirms the two drugs’ functional equivalence, despite their structural differences. The implications of dose conversion ratios and costs to Medicare are subsequently explored. It is argued that the issue of dose equivalence between epoetin-α and darbepoetin-α has significant implications for patients, practitioners, and payors. A payor’s perspective is adopted in this respect, whereby clinical evidence and pricing data are used simultaneously. Based on the clinical evidence, a dose conversion ratio for epoetin-α:darbepoetin-α is established, which achieves a comparable clinical effect for the two drugs and this is set to be <254IU:1μg. The incremental costs to Medicare are calculated subsequently. The Average Wholesale Price and the Outpatient Prospective Payment System rule that Medicare uses to reimburse providers are used and suggest that treatment of cancer patients with chemotherapy-related anemia with epoetin-α would save Medicare an estimated $US600 million each year. Patients would also benefit significantly in terms of lower co-payments for epoetin-α. The evidence is supportive of the decision made by the CMS to reimburse the two drugs at the rate reflecting the achievement of comparable clinical effects and therefore reducing the pass-through payments for darbepoetin-α to zero for the 2002–3 fiscal year. 相似文献
89.
Usher syndrome: clinical findings and gene localization studies 总被引:3,自引:0,他引:3
William J. Kimberling Sandra L. H. Davenport Ira Priluck Valorie White Karen Biscone-Halterman Patrick E. Brookhouser Claes G. Mller Gunnar Lund Timothy J. Grissom Michael D. Weston 《The Laryngoscope》1989,99(1):66-72
The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized. 相似文献
90.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis. 相似文献