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41.
J Isherwood G Garcea R Williams M Metcalfe AR Dennison 《Annals of the Royal College of Surgeons of England》2014,96(3):224-228
Introduction
Magnetic resonance cholangiopancreatography (MRCP) is not a routine investigation to exclude choledocholithiasis unless there is clinical or biochemical suspicion of common bile duct (CBD) stones. This study attempted to determine which radiological or serological parameters best predicted CBD stones.Methods
All patients undergoing MRCP from 2005 to 2011 were selected. Patients with pancreatitis were excluded. Liver function tests (LFTs) at admission and prior to MRCP were recorded, as was abdominal ultrasonography and MRCP results. Parameters measured routinely on LFTs included alkaline phosphatase (ALP), alanine transaminase (ALT) and bilirubin. Receiver operating characteristic curve area analysis (area under the curve [AUC]) and chi-squared analysis were undertaken.Results
Overall, 195 patients were identified, 71 of whom had CBD stones on MRCP. Raised ALP levels on admission demonstrated a correlation with CBD stones (AUC: 0.619, odds ratio [OR]: 3.16, p=0.06). At ultrasonography, a dilated CBD (OR: 3.76, p<0.001) and intrahepatic duct dilation (OR: 5.56, p<0.001) were highly significant predictors. However, only 37% of patients had a dilated CBD on ultrasonography. Ongoing elevation of LFT parameters, particularly ALP (AUC: 0.707, OR: 4.64, p<0.001) and ALT (AUC: 0.646, OR: 5.40, p<0.001), displayed a significant correlation with CBD stones.Conclusions
Ongoing (even if minor) elevations of liver function test parameters should prompt the need to exclude CBD stones even in the presence of a normal CBD diameter on ultrasonography. 相似文献42.
We have developed a general quenched-flow approach to study platelet function as early as 0.3 seconds after stimulation. Phosphorylation of 20- and 40-kd proteins has been analyzed during the first five seconds of platelet response to thrombin from 0.1 to 5.0 U/mL and compared with the progress of aggregation and serotonin secretion. The onset time for aggregation and phosphorylation of both proteins was less than one second, although with lowest (less than 0.5 U/mL) thrombin levels, a lag of up to 0.6 seconds occurred before 40K phosphorylation increased. The thrombin sensitivity of aggregation and 20K phosphorylation was approximately twice that of 40K phosphorylation, with Ka values of 0.51 and 0.53 v 1.10 U/mL, respectively. External calcium was necessary for maximal 20K phosphorylation, since EDTA inhibited this by 30%. The 40K phosphorylation was not affected by EDTA. Platelet activation by thrombin thus induced biochemical changes well before one second. The quenched-flow approach may help to reveal relationships between phospholipase activation, calcium fluxes, and protein phosphorylation during these early periods of platelet function. 相似文献
43.
Diagnostic role of an immunoassay-detected polymorphism of factor IX for potential carriers of hemophilia B 总被引:3,自引:1,他引:3
In hemophilia B, assays based on a monoclonal antifactor IX specific for the Thr-148 variant of an exonic polymorphism have diagnosed carriers in selected families by either establishing linkage or by indicating the presence or absence of a given normal factor IX. The sensitivity of the immunoassays for detecting heterozygous women was explored by comparing results from immunoassays with solid-phase polyclonal v the monoclonal antifactor IXs. Factor IX with the normal Ala-148 variant gave a flat dilution curve, qualitatively distinct from factor IX with the Thr-148 variant in the monoclonal assay. The two were indistinguishable in the polyclonal assay. Mixtures of equal amounts of the two types gave an intermediate result, about half as reactive in the monoclonal as compared with the polyclonal assay system. Whereas mixtures with 10% Ala-148 and 90% Thr-148 factor IXs could not readily be distinguished from Thr-148 factor IX plasma, as little as 1% of the Thr-148 protein was detected in Ala-148 factor IX plasma. The frequency of the Ala-148 variant varied in individuals with different ethnic backgrounds; it was found in 29% of white, 12% of black, and none of Asian blood donors' factor IX genes in Seattle. Only 4% of samples from South African black men were nonreactive (ie, Ala- 148). The Thr/Ala-148 dimorphism is in strong linkage disequilibrium with Taql restriction fragment length polymorphisms (RFLPs). Three recombinations were noted in normal white genes and one in a normal black factor IX gene (less than 2% of those examined). In 34 white families with at least one woman being a possible carrier, genetically, the immunoassay results were informative in 18. RFLP analyses were informative in eight of the 15 families tested. In five families each, assignment of carrier status was made to a woman by only DNA or only immunoassay results, whereas the other approach was noninformative. The immunoassays provide a rapid, inexpensive screening test and complement DNA analysis in white women who are potential carriers of hemophilia B. 相似文献
44.
STUDY OBJECTIVE: Patients with cystic fibrosis (CF) frequently require recurrent courses of IV antibiotics to treat acute exacerbations of their pulmonary disease. Over time, CF patients often lose peripheral access, and indwelling central venous catheters are placed. We attempted to determine the type and incidence of catheter complications so that CF patients could be fully informed of the risks prior to placement of these catheters. DESIGN: The charts of all CF patients who attended the Adult Cystic Fibrosis Clinic of the University of Washington Medical Center from January 1989 through December 1998 were reviewed. Demographic information was obtained along with the type and duration of catheter, type and number of complications, and the use of anticoagulant medication. MEASUREMENTS AND RESULTS: Of the 218 CF patients who attended the clinic, 65 patients (30%) had indwelling catheters in place at some time during the study period. A total of 87 catheters were placed into these 65 patients. The total number of catheter-days for first indwelling catheters was 68,220. The total number of catheter-days for all catheters was 75,660 (210 catheter-years). Thirty-five catheter-related complications were identified, occurring in 26 patients. Complications included thrombosis (n = 14), infections (n = 9), mechanical problems (n = 6), pneumothorax (n = 3), superior vena cava syndrome/stenosis (n = 2), and air embolism (n = 1), for an overall complication rate of 0. 463/1,000 catheter-days. CONCLUSION: We conclude that indwelling catheters are relatively safe in patients with CF. Good infection control policies appear to prevent most infectious complications. The most common complication is that of thrombosis, which may be recurrent in some patients. Consideration should be given to prophylactic warfarin therapy despite the potential risk of significant hemoptysis in this patient population. 相似文献
45.
Intraoperative Parathormone Measurement in Patients with Multiple Endocrine Neoplasia Type I Syndrome and Hyperparathyroidism 总被引:1,自引:0,他引:1
Tonelli F Spini S Tommasi M Gabbrielli G Amorosi A Brocchi A Brandi ML 《World journal of surgery》2000,24(5):556-563
Total or subtotal parathyroidectomy is considered the treatment of choice for multiple endocrine neoplasia type I (MEN-I)-associated
primary hyperparathyroidism (HPT). However, persistent or recurrent HPT is frequently observed. The development of a rapid
two-site immunoradiometric assay (IRMA) method for measuring intact parathormone (PTH) has provided a valuable tool for recognizing
possible surgical failures. Our experience includes 16 MEN-I patients (10 females, 6 males) of mean age 35.5 years operated
on between 1990 and 1996. Total parathyroidectomy (TPTX) with autotransplantation of parathyroid tissue was the standard treatment.
Blood samples for PTH measurement were drawn at the induction of anesthesia (basal value), 10 and 20 minutes after the removal
of each gland, and 60 minutes after TPTX. Rapid PTH measurement, which required only 15 minutes of incubation at 37°C, showed
a highly significant correlation (p < 0.0001) with the standard method. Circulating PTH levels exhibited a stepwise decrease during TPTX, reaching a mean value
of 22.3% of the baseline 20 minutes after removal of the last gland. Two patients showed a prompt decrease of PTH after removal
of the single enlarged gland, featuring the kinetics observed in the adenomas. One of these two patients was successfully
treated with more conservative surgery. None of the patients showed persistence or recurrence of HPT. In our experience, intraoperative
measurement of PTH seems to be a valuable adjunct in both the diagnosis of multiglandular involvement and the prediction of
surgical treatment in patients with primary parathyroid hyperplasia. 相似文献
46.
Hyperbaric oxygen therapy improves angiogenesis and bone formation in critical sized diaphyseal defects 下载免费PDF全文
JP Grassmann J Schneppendahl AR Hakimi M Herten M Betsch TT Lögters S Thelen M Sager M Wild J Windolf P Jungbluth M Hakimi 《Journal of orthopaedic research》2015,33(4):513-520
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015. 相似文献
47.
48.
J Saki AR Meamar H Oormazdi L Akhlaghi S Maraghi M Mohebali S Khademvatan E Razmjou 《Iranian Journal of Parasitology》2010,5(1):25-34
Background
Leishmaniasis is a protozoan disease cause by Leishmania genus. Anthroponotic and zoonotic cutaneous leishmaniasis are endemic in Iran. The aim of this study was to identify the causative agent of cutaneous leishmaniasis by mini-exon gene in five regions of Khuzestan Province, southwest of Iran.Methods
From 2007 to 2008 in this cross-sectional study, cutaneous samples were collected from patients referred to Health Centers and Hospitals of the Khuzestan Province for cutaneous leishmaniasis diagnosis and cultured in Novy-MacNeal-Nicolle (NNN) and RPMI 1640. The propagated promastigotes were harvested and Leishmania species of cutaneous leishmaniasis were identified by RFLP and DNA sequencing of the PCR generated fragments.Results
L. major and L. tropica were the causative agents of cutaneous leishmaniasis by predominantly of L. major species. The alignment of the mini-exon sequencing isolates with reported sequencing of L. major and L. tropica revealed 92%-99% identity.Conclusion
Our study showed that mini-exon PCR-RFLP was useful method to identify the causative species of cutaneous leishmaniasis. 相似文献49.
50.