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1.
Hypertriglyceridemia-induced acute pancreatitis (HGAP) is the third most common etiology of acute pancreatitis. HGAP can be attributed to genetic disturbances in triglyceride metabolism or multiple secondary causes. Here, we presented three cases for HGAP and explored different therapeutic approaches for treating HGAP. A case series of three patients who presented with HGAP and underwent different therapeutic approaches was conducted. The first patient was a 37-year-old male who presented with nonsevere HGAP; he was treated with conservative therapy with insulin and heparin infusion, which resulted in clinical and laboratory improvement. The second patient was a 64-year-old male with human immunodeficiency virus on multiple highly active antiretroviral therapy. He presented with severe HGAP and multiorgan failure. After initiation of therapeutic plasma exchange, his HGAP resolved. The third patient was a 28-year-old male who presented with recurrent episodes of HGAP; his conservative therapy failed and was eventually escalated to therapeutic plasma exchange (TPE). HGAP can be attributed to genetic disturbances of lipid or secondary etiologies. A nonsevere form of HGAP can be managed with conventional therapy including insulin and heparin; however, severe HGAP may require TPE.  相似文献   
2.
Static and cyclic loading of fiber-reinforced dental resin.   总被引:13,自引:0,他引:13  
OBJECTIVE: The aim of this study was to evaluate the flexure strength of unidirectional fiber-reinforced resins under static and cyclic loading with and without thermal cycling. METHODS: The fiber-reinforced resin materials chosen for this project were commercially available endodontic posts and commercially procured bar samples. For all materials, controls for flexure strength were tested in air and in water using three-point loading. Specimens were thermal cycled between 7 and 63 degrees C for 6000 cycles. A staircase approach was used to determine the flexure fatigue limit and scanning microscopy was used to examine the microstructure. RESULTS: The carbon/graphite fiber-reinforced resin posts and the glass FiberKor posts were significantly stronger than the ceramic (zirconia) and the other glass-reinforced resin materials. Thermal cycling caused a significant lowering (11-24%) of the flexure strength for each resin based post system. The ceramic post system decreased only by 2%. Further, for standard size glass fiber-reinforced resin bars, no significant differences between testing in air and water was observed, but a significant difference between static and cyclic loading was noted. SIGNIFICANCE: The decreases in the strength property due to thermal cycling and the cyclic loading of these materials indicates that their utilization in the oral environment enhances their degradation, and potentially shortens their clinical life.  相似文献   
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This article describes a variant of palmaris longus muscle resulting in median nerve compression in the mid forearm. Although the palmaris longus has several well-documented anomalies, these seldom lead to nerve compression. The dual tendon, central muscle belly variant observed in this case is the first of its kind to be reported causing compressive neuropathy at this level. This is of both anatomical and clinical interest as it reminds surgeons of the anatomical variations of this unique muscle and presents a new mechanism of nerve compression in the forearm.  相似文献   
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Background:

Meningitis remains a serious clinical problem in developing as well as developed countries. Delay in diagnosis and treatment results in significant morbidity and mortality. The role and levels of intrathecal endogenous cortisol is not known.

Objective:

To study the cerebrospinal fluid (CSF) cortisol levels and to evaluate its role as a diagnostic and therapeutic marker in acute bacterial meningitis.

Materials and Methods:

Thirty patients with acute bacterial meningitis with no prior treatment were evaluated. Cortisol levels were compared with 20 patients with aseptic (viral) meningitis and 25 control subjects.

Results:

Mean CSF cortisol level was 13.85, 3.47, and 1.05 in bacterial meningitis, aseptic meningitis, and controls, respectively. Mean CSF cortisol level in bacterial meningitis was significantly higher as compared to controls (P < 0.001). There was significant difference in CSFcortisol levels in bacterial and aseptic meningitis (P < 0.001).

Conclusions:

Cortisol levels in CSF are highly elevated in patients with acute bacterial meningitis. This suggests that intrathecalcortisol may serve as a valuable, rapid, relatively inexpensive diagnostic marker in discriminatingbetween bacterial and aseptic meningitis. This helps in earlier institution of appropriate treatment and thereby decreasing morbidity and mortality.  相似文献   
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Cypermethrin, a class II pyrethroid pesticide, is used to control insects in the household and agricultural fields. Despite beneficial roles, its uncontrolled and repetitive applications lead to unintended effects in non-target organisms. Cypermethrin crosses the blood-brain barrier and induces neurotoxicity and motor deficits. Cypermethrin prolongs the opening of sodium channel, a major site of its action, leading to hyper-excitation of the central nervous system. In addition to sodium channel, cypermethrin modulates chloride, voltage-gated calcium and potassium channels, alters the activity of glutamate and acetylcholine receptors and adenosine triphosphatases and induces DNA damage and oxidative stress in the neuronal cells. Cypermethrin also modulates the level of neurotransmitters, including gamma-aminobutyric acid and dopamine. It is one of the most commonly used pesticides in neurotoxicology research not only because of its variable responses depending upon the doses, time and routes of exposure and strain, age, gender and species of animals used across multiple studies but also owing to its ability to induce the nigrostriatal dopaminergic neurodegeneration. This article describes the effect of acute, chronic, developmental and adulthood exposures to cypermethrin in experimental animals. The article sheds light on cypermethrin-induced changes in the central nervous system, including its contribution in the onset of specific features, which are associated with the nigrostriatal dopaminergic neurodegeneration. Resemblances and dissimilarities of cypermethrin-induced nigrostriatal dopaminergic neurodegeneration with sporadic and chemicals-induced disease models along with its advantages and pitfalls are also discussed.  相似文献   
9.
ABSTRACT: BACKGROUND: A significant number of cancers are caused by defects in p21 causing functional defects in p21 or p53 tumour-suppressor proteins. This has led to many therapeutic approaches including restoration by gene therapy with wild-type p53 or p21 using viral or liposomal vectors, which have toxicity or side-effect limitations. We set out to develop a safer, novel fusion protein which has the ability to reconstitute cancer cell lines with active p21 by protein transduction. METHODS: The fusion protein was produced from the cell-translocating peptide Antennapedia (Antp) and wild-type, full-length p21 (Antp-p21). This was expressed and refolded from E. coli and tested on a variety of cell lines and tumours with differing p21 or p53 status. RESULTS: Antp-p21 penetrated and killed cancer cells that do not express wild type p53 or p21. This included cells that were matched to cogenic parental cell lines. Antp-p21 killed cancer cells selectively that were malignant as a result of mutations or nuclear exclusion of the p53 and p21 genes and over-expression of MDM2. Non-specific toxicity was excluded by showing that Antp-p21 penetrated but did not kill p53- or p21- wild-type cells. Antp-p21 was not immunogenic in rabbits. Recombinant Antp peptide alone was not cytotoxic, showing that killing was due to the transduction of the p21 component of Antp-p21. Antp-p21 was shown to penetrate cancer cells engrafted in vivo and resulted in tumour eradication when administered with conventionally-used chemotherapeutic agents, which alone were unable to produce such an effect. CONCLUSIONS: Antp-p21 may represent a new and promising targeted therapy for patients with p53-associated cancers supporting the concept that rational design of therapies directed against specific cancer mutations will play a part in the future of medical oncology.  相似文献   
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