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991.

Background

The value of lung ultrasonography in the diagnosis of respiratory dysfunction and severity stratification in patients with acute pancreatitis (AP) was investigated.

Methods

Over a 3-month period, 41 patients (median age: 59.1 years; 21 males) presenting with a diagnosis of potential AP were prospectively recruited. Each participant underwent lung ultrasonography and the number of comet tails was linked with contemporaneous clinical data. Group comparisons, areas under the curve (AUC) and respective measures of diagnostic accuracy were investigated.

Results

A greater number of comet tails were evident in patients with respiratory dysfunction (P = 0.021), those with severe disease (P < 0.001) and when contemporaneous and maximum CRP exceeded 100 mg/L (P = 0.048 and P = 0.003 respectively). Receiver-operator characteristic plot area under the curve (AUC) was greater when examining upper lung quadrants, using respiratory dysfunction and AP severity as variables of interest (AUC = 0.783, 95% C.I.: 0.544–0.962, and AUC = 0.996, 95% C.I.: 0.982–1.000, respectively). Examining all lung quadrants except for the lower lateral resulted in greater AUCs for contemporaneous and maximum CRP (AUC = 0.708, 95% C.I.: 0.510–0.883, and AUC = 0.800, 95% C.I.: 0.640–0.929).

Discussion

Ultrasonography of non-dependent lung parenchyma can reliably detect evolving respiratory dysfunction in AP. This simple bedside technique shows promise as an adjunct to severity stratification.  相似文献   
992.
993.
Nodular primary localized cutaneous amyloidosis is an uncommon disorder for which there is no consistently satisfactory treatment. The amyloid fibrils are thought to have an immunoglobulin light chain derivation and systemic involvement must be excluded in all cases. We report a patient with a large scalp lesion of nodular primary localized cutaneous amyloidosis whose immunohistochemical evaluation revealed lambda light chain deposits and who thus far has no apparent systemic involvement. The lesion was treated by the carbon dioxide (CO2) laser with excellent cosmetic results and minimal morbidity.  相似文献   
994.
Four patients with severe psoriasis have been treated with oral cyclosporine for 6 months. Two had generalized erythroderma and two had extensive plaque-type psoriasis; all had either become unresponsive to or were unable to use other accepted treatments. All four patients responded rapidly and were completely clear of psoriasis within 3 weeks of beginning therapy. Initial doses ranged from 7.5 to 8.5 mg/kg/day. Mild reversible nephrotoxicity occurred in the one patient whose cyclosporine trough level briefly exceeded 200 ng/ml. Cyclosporine may offer an alternative therapeutic modality in the management of erythrodermic or severe resistant plaque-type psoriasis. The effectiveness of cyclosporine in psoriasis underscores the putative role of cell-mediated immune factors in the pathogenesis of psoriasis.  相似文献   
995.

Background and purpose

Target volumes and organs-at-risk (OARs) for radiotherapy (RT) planning are manually defined, which is a tedious and inaccurate process. We sought to assess the feasibility, time reduction, and acceptability of an atlas-based autosegmentation (AS) compared to manual segmentation (MS) of OARs.

Materials and methods

A commercial platform generated 16 OARs. Resident physicians were randomly assigned to modify AS OAR (AS + R) or to draw MS OAR followed by attending physician correction. Dice similarity coefficient (DSC) was used to measure overlap between groups compared with attending approved OARs (DSC = 1 means perfect overlap). 40 cases were segmented.

Results

Mean ± SD segmentation time in the AS + R group was 19.7 ± 8.0 min, compared to 28.5 ± 8.0 min in the MS cohort, amounting to a 30.9% time reduction (Wilcoxon p < 0.01). For each OAR, AS DSC was statistically different from both AS + R and MS ROIs (all Steel–Dwass p < 0.01) except the spinal cord and the mandible, suggesting oversight of AS/MS processes is required; AS + R and MS DSCs were non-different. AS compared to attending approved OAR DSCs varied considerably, with a chiasm mean ± SD DSC of 0.37 ± 0.32 and brainstem of 0.97 ± 0.03.

Conclusions

Autosegmentation provides a time savings in head and neck regions of interest generation. However, attending physician approval remains vital.  相似文献   
996.
997.
Sphingosine-1-phosphate (S1P(1)) receptor agonists such as Fingolimod (FTY-720) are a novel class of immunomodulators that have clinical utility in the treatment of remitting relapsing multiples sclerosis. This class of compound act by inducing peripheral lymphopenia. Using an integrated pharmacokinetic/pharmacodynamic (PK-PD) approach based on an in vivo rat model, novel S1P(1) agonists were identified with a predicted more rapid rate of reversibility of lymphocyte reduction in human compared to Fingolimod. The in vivo potency of 15 compounds based on PK-PD modelling of the rat lymphocyte reduction model was correlated with in vitro measures of potency at the S1P(1) receptor using β arrestin recruitment and G-protein signalling. A structurally novel S1P(1) agonist was identified and predictions of human pharmacokinetics and clinical dose are presented.  相似文献   
998.
BackgroundA standardized definition of post-hepatectomy haemorrhage (PHH) has not yet been established.MethodsAn international study group of hepatobiliary surgeons from high-volume centres was convened and a definition of PHH was developed together with a grading of severity considering the impact on patients' clinical management.ResultsThe definition of PHH varies strongly within the hepatic surgery literature. PHH is defined as a drop in haemoglobin level >3 g/dl post-operatively compared with the post-operative baseline level and/or any post-operative transfusion of packed red blood cells (PRBC) for a falling haemoglobin and/or the need for radiological intervention (such as embolization) and/or re-laparotomy to stop bleeding. Evidence of intra-abdominal bleeding should be obtained by imaging or blood loss via the abdominal drains if present. Transfusion of up to two units of PRBC is considered as being Grade A PHH. Grade B PHH requires transfusion of more than two units of PRBC, whereas the need for invasive re-intervention such as embolization and/ or re-laparotomy defines Grade C PHH.ConclusionThe proposed definition and grading of severity of PHH enables valid comparisons of results from different studies. It is easily applicable in clinical routine and should be applied in future trials to standardize reporting of complications.A proposed international definition and grading of severity of post hepatectomy haemorrhage which may enable better comparison of outcomes from future published studies  相似文献   
999.

Background and aim

Appropriate and timely initial fluid resuscitation in acute pancreatitis (AP) is critical. The aim of this retrospective study was to evaluate fluid therapy on an hour-by-hour basis in relation to standard indices of adequate resuscitation during AP.

Methods

Emergency room shock charts, fluid balance sheets and intensive care (ICU) charts for all patients with AP admitted to ICU in a large acute hospital were examined. Vital signs, clinical course and fluid administered during the first 72 h after admission were tabulated against urine output, central venous pressure (CVP) and inotrope/vasopressor therapy.

Results

Sixty-three consecutive patients with AP were initially evaluated. Inter-hospital transfers with established organ dysfunction (n = 11) or where records had insufficient detail (n = 22) were excluded. In the remaining 30 patients, in-hospital death occurred in 7. The cumulative volume of crystalloid given was significantly less at 48 h in patients who died in hospital (3331 ± 800 ml vs. survivors, 7287 ± 544 ml; P < 0.001). Non-survivors had a higher CVP, and received more inotropes/vasopressors.

Conclusion

In severe AP-associated organ failure, fluid resuscitation profiles differ between survivors and non-survivors. CVP alone as a crude indicator of adequate resuscitation may be unreliable, potentially leading to the use of inotropes/vasopressors in the inadequately filled patient.  相似文献   
1000.
Spinocerebellar ataxia type 7 (SCA7) is a dominantly inherited disorder characterized by cerebellum and brainstem neurodegeneration. SCA7 is caused by a CAG/polyglutamine (polyQ) repeat expansion in the ataxin-7 gene. We previously reported that directed expression of polyQ-ataxin-7 in Bergmann glia (BG) in transgenic mice leads to ataxia and non-cell-autonomous Purkinje cell (PC) degeneration. To further define the cellular basis of SCA7, we derived a conditional inactivation mouse model by inserting a loxP-flanked ataxin-7 cDNA with 92 repeats into the translational start site of the murine prion protein (PrP) gene in a bacterial artificial chromosome (BAC). The PrP-floxed-SCA7-92Q BAC mice developed neurological disease, and exhibited cerebellar degeneration and BG process loss. To inactivate polyQ-ataxin-7 expression in specific cerebellar cell types, we crossed PrP-floxed-SCA7-92Q BAC mice with Gfa2-Cre transgenic mice (to direct Cre to BG) or Pcp2-Cre transgenic mice (which yields Cre in PCs and inferior olive). Excision of ataxin-7 from BG partially rescued the behavioral phenotype, but did not prevent BG process loss or molecular layer thinning, while excision of ataxin-7 from PCs and inferior olive provided significantly greater rescue and prevented both pathological changes, revealing a non-cell-autonomous basis for BG pathology. When we prevented expression of mutant ataxin-7 in BG, PCs, and inferior olive by deriving Gfa2-Cre;Pcp2-Cre;PrP-floxed-SCA7-92Q BAC triple transgenic mice, we noted a dramatic improvement in SCA7 disease phenotypes. These findings indicate that SCA7 disease pathogenesis involves a convergence of alterations in a variety of different cell types to fully recapitulate the cerebellar degeneration.  相似文献   
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