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991.
992.
Trehan VK Mukhopadhyay S UmaMahesh CR Yusuf J Suryavanshi S Arora R 《Indian heart journal》2002,54(6):702-704
Pseudoaneurysm following diagnostic or interventional procedures is a well-known complication. We describe a new method of closing a femoral pseudoaneurysm in a case where ultrasound-guided compression had failed. Instead of packing the sac permanently with coils, thrombus formation was successfully induced by temporary placement of a coil transcutaneously in the psendoaneurysm sac, which resulted in closure of the pseudoaneurysm. 相似文献
993.
Compliance with treatment can be an important determinant of the outcome of clinical trials. To date there is no completely satisfactory method of measuring compliance and some of the most widely used methods are inadequate. The various methods of measuring compliance and how they have been applied to clinical trials are described, and improvements in the standard of the measurement and reporting of compliance in clinical trials are suggested. 相似文献
994.
Specific molecular recognition of mixed nucleic acid sequences: an aromatic dication that binds in the DNA minor groove as a dimer 下载免费PDF全文
Wang L Bailly C Kumar A Ding D Bajic M Boykin DW Wilson WD 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(1):12-16
Phenylamidine cationic groups linked by a furan ring (furamidine) and related compounds bind as monomers to AT sequences of DNA. An unsymmetric derivative (DB293) with one of the phenyl rings of furamidine replaced with a benzimidazole has been found by quantitative footprinting analyses to bind to GC-containing sites on DNA more strongly than to pure AT sequences. NMR structural analysis and surface plasmon resonance binding results clearly demonstrate that DB293 binds in the minor groove at specific GC-containing sequences of DNA in a highly cooperative manner as a stacked dimer. Neither the symmetric bisphenyl nor bisbenzimidazole analogs of DB293 bind significantly to the GC containing sequences. DB293 provides a paradigm for design of compounds for specific recognition of mixed DNA sequences and extends the boundaries for small molecule-DNA recognition. 相似文献
995.
Kumar D Farrell GC Kench J George J 《Journal of gastroenterology and hepatology》2005,20(9):1395-1400
BACKGROUND AND AIM: Obesity associated hepatic steatosis has been suggested to have a premalignant potential. We determined whether hepatic steatosis predisposes to liver cancer in persons with chronic hepatitis C virus (HCV) infection. METHODS: We compared the histological severity of steatosis in the index liver biopsies of 25 patients with chronic hepatitis C who subsequently developed hepatocellular carcinoma (HCC) with matched controls who did not. Cases were aged (mean) 54.7 years, 84% males, 76% genotype 1, and 64% fibrosis stage 4; and controls were matched for these characteristics. Those with a sustained virologic response to antiviral therapy were excluded. RESULTS: Duration of HCV infection, concomitant alcohol intake, body mass index and indices of past hepatitis B virus (HBV) infection were comparable between the groups. Controls were followed for a longer period after the index liver biopsy than were cases (113 months vs 55 months, P < 0.001). As determined by percentage area of biopsy core occupied by steatosis on computer assisted morphometric evaluation, and graded by semiquantitative histological assessment, steatosis was comparable among cases and controls. The odds of developing HCC among those with steatosis grades 1 and 2 did not differ significantly from those without steatosis. There was no association between increasing morphometric percentage area occupied by steatosis and the subsequent development of HCC. Neither steatosis grade or percent area of steatosis on biopsy were selected in multivariate regression analysis as independent predictors for the development of HCC. CONCLUSIONS: Hepatic steatosis does not augment the risk of hepatocarcinogenesis in patients with chronic HCV infection. 相似文献
996.
Kumar SK Dingli D Lacy MQ Dispenzieri A Hayman SR Buadi FK Rajkumar SV Litzow MR Gertz MA 《British journal of haematology》2008,141(2):205-211
A third of patients with multiple myeloma (MM) have a preceding diagnosis of plasma cell proliferative disorder (PCPD), mostly monoclonal gammopathy of undetermined significance (MGUS), smoldering MM (SMM) or plasmacytoma. While autologous stem cell transplantation (SCT) improves survival in MM, it is not clear if patients with preceding PCPD have a different outcome. We identified 151 patients with preceding PCPD from among 804 patients undergoing SCT, and their outcomes were compared. The response rates, including complete responses, were similar between the groups. Patients with a preceding diagnosis of MGUS had longer time to progression (TTP; 27·5 months vs. 17·2 months, P = 0·01), and longer overall survival (OS) from transplant (80·2 months vs. 48·3 months, P = 0·03) compared to those with de novo myeloma. However no differences were seen among those with a preceding diagnosis of SMM or plasmacytoma in terms of TTP or OS from transplant when compared to those with de novo myeloma. Multivariate analysis indicated that the presence of MGUS prior to myeloma was prognostic for post-transplant relapse independent of other known risk factors. Patients with pre-existing MGUS prior to myeloma diagnosis have a better outcome following HDT, reflecting more indolent disease and a favourable biology than those presenting with de novo myeloma. 相似文献
997.
Melatonin, released from the pineal gland, is an important signal within the circadian pacemaking system of passeriform birds. Until now, seasonal variations in melatonin production have only been examined in a few avian species and the role of melatonin in the regulation of annual rhythms in birds is unclear. We investigated plasma melatonin in a group of house sparrows kept in an outside aviary in spring (March/April), summer (May/June), autumn (September/October), and winter (December/January). The durations of elevated melatonin values mirrored the seasonal changes in night length to a certain degree, the melatonin signal being longest in winter and shortest in summer. Additionally, plasma melatonin peak amplitudes differed significantly among seasons, with highest values in spring and summer and lowest values in winter. Cultured explanted pineal glands obtained from animals in winter and summer showed patterns of in vitro melatonin release comparable to in vivo circulating melatonin with different durations of elevated melatonin and peak amplitude values. These data indicate that the circadian pacemaking system of the house sparrow changes properties seasonally, either as a result of endogenous mechanisms or in response to environmental conditions. These properties are maintained in the pineal gland even after isolation from the animal. 相似文献
998.
999.
Normal pregnancy has been considered as a controlled state of inflammation at an early stage of blastocyst implantation that subsequently develops systemically. Till recent past most popular hypotheses regarding status of immune system in pregnancy were dominated by the Th1 and Th2 hypothesis, in which the fetus avoids maternal rejection through a bias towards T-helper (Th2) cytokine production. Recent findings have shown that predominant immune interactions in the human deciduas are between the placental trophoblast and maternal uterine natural killer (uNK) cells rather than the T cells. Thus NK cells are emerging as important players in the uterine immune response to invasive forms of placenta, as in cases of hemochorial placenta. In humans there is a lack of evidence for T-cell responses to trophoblast cells; therefore it was thought that uterine NK cells are the key factors by which the maternal immune system recognizes trophoblast cells. In this review we are trying to summarize the role of uNK cells in the maintenance of normal pregnancy in humans. 相似文献
1000.