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排序方式: 共有430条查询结果,搜索用时 593 毫秒
101.
Quante M Appenrodt B Randerath S Wolff M Fischer HP Sauerbruch T 《Scandinavian journal of gastroenterology》2009,44(1):116-120
A 55-year-old woman with suspected hilar cholangiocarcinoma presented with jaundice and dilated intrahepatic bile ducts owing to high-grade hepatic duct confluence stenosis. The suspected tumour and the entire extrahepatic bile duct system were resected and Roux-en-Y hepaticojejunostomy was performed. Histological investigations showed perihepatic fibrosis but no signs of malignancy. One year later the patient developed bilateral hydronephrosis caused by ureteral obstruction. Since the patient had a gynaecological history of widespread inflammation, she was referred for transabdominal operative ureterolysis combined with hysterectomy and adnexectomy. Histological investigations as well as fluorodeoxyglucose-positron emission tomography (FDG-PET) and computed tomography (CT) findings were compatible with retroperitoneal fibrosis (Ormond's disease). Treatment with tamoxifen was initiated. To the best of our knowledge, only a few cases of intraperitoneal fibroses mimicking cholangiocarcinoma followed by the typical symptoms of retroperitoneal Ormond's disease have been reported. 相似文献
102.
Mirja Neizel Wiebke Kaestner Malte Kelm Harald P. Kühl 《Current cardiovascular imaging reports》2009,2(2):124-129
Identification of the functional severity of intermediate coronary artery lesions is challenging for the interventional cardiologist.
Functional severity can be measured invasively using the fractional flow reserve (FFR). However, FFR has the disadvantage
of being invasive and associated with radiation exposure. Cardiac MRI (CMR) offers the opportunity to assess myocardial perfusion
noninvasively. A semiquantitative index of myocardial perfusion (perfusion reserve index or PRI) can be obtained from the
first-pass of a bolus of gadolinium through the myocardium. Studies comparing the invasive FFR to CMR perfusion imaging in
patients with coronary artery stenosis of undefined significance have demonstrated that CMR first-pass perfusion imaging may
be useful for the assessment of their functional significance. However, in patients with a high prevalence of microvascular
dysfunction, the value of this method may be limited because the PRI may be influenced by both the epicardial conductance
vessel function as well as microvascular function. 相似文献
103.
Patients with coronary artery disease (CAD) undergoing noncardiac surgery (NCS) pose a special challenge for the anaesthesiologist, as the risk of serious perioperative cardiac complications, which represent a significant cause of morbidity and mortality, is increased in this population. Here we report about a patient with a solitary liver metastasis, who was admitted for hemihepatectomy. The patient with a known single vessel CAD, reporting no current cardiac problems, was cleared for the surgical procedure which carries a high risk of cardiac complications. Cardiology reports were present for evaluation. After an unremarkable placement of the peridural catheter and endotracheal intubation the patient presented with bradycardia and hypotension. Pharmacological resuscitation was initiated. After the patient was stabilized and the differential diagnosis suggested a cardiac problem, surgery was postponed. Following the end of anaesthesia, the patient remained in stable condition without catecholamine support. Coronary angiography on the next day revealed a progression of the CAD. The peridural catheter was removed before the intervention, Aspirin and clopidogrel were given on the same day. The patient was operated successfully without complications six weeks after the coronary intervention. 相似文献
104.
Migraine in children and adolescents: a guide to drug treatment 总被引:2,自引:0,他引:2
Hämäläinen ML 《CNS drugs》2006,20(10):813-820
Migraine is a common disorder in children and adolescents, with a prevalence of 5 and 10%, respectively. Some patients may have recognisable factors that trigger or aggravate migraine attacks, such as flickering or bright lights, strong smells and noise, and where possible these should be avoided. It is also wise to maintain a lifestyle where children receive regular meals and get sufficient sleep. If used, acute pharmacological treatment should be given at the onset of an attack, followed by a rest or sleep. According to recent literature, paracetamol (acetaminophen) and ibuprofen can be recommended for the acute treatment of migraine attacks in children and adolescents, and sumatriptan nasal spray can be recommended for adolescents. The oral formulation of sumatriptan has not shown efficacy in paediatric patients, and the subcutaneous injection, although somewhat effective, is not an ideal formulation for this patient group. There are too few data on the efficacy of the other 'triptans' to recommend their use in children and adolescents. There are less data on the use of prophylactic drugs in paediatric patients. In systematic studies, only flunarizine, which is not available in many countries, and propranolol have been found to be effective. A pilot placebo-controlled study suggests that topiramate might also be effective. Several other agents are commonly used to prevent migraine attacks in children (e.g. amitriptyline, valproic acid [sodium valproate]) despite a lack of robust research into their efficacy. 相似文献
105.
The higher toxicity of cereulide relative to valinomycin is due to its higher affinity for potassium at physiological plasma concentration 总被引:5,自引:0,他引:5
Teplova VV Mikkola R Tonshin AA Saris NE Salkinoja-Salonen MS 《Toxicology and applied pharmacology》2006,210(1-2):39-46
Valinomycin and cereulide are bacterial toxins with closely similar chemical structure and properties but different toxic effects. Emetic poisoning is induced by cereulide but not by valinomycin. Both are specific potassium ionophores. Such compounds may affect mitochondrial functions. Both compounds cause a potassium-dependent drop in the transmembrane inner membrane potential due to the uptake of K+ as positively charged ionophore complex. Valinomycin is more potent than cereulide at high [K+] (>80 mM), whereas cereulide in contrast to valinomycin is active already at <1 mM. With cereulide, there is a substantial lag, while valinomycin acts without lag. Both ionophores induce mitochondrial swelling in the presence of K+, in the case of cereulide with a lag. These toxins strongly inhibited respiration at the level of complex IV when used at higher concentrations than that used for detection of ionophoretic transport of K+. At high [KCl] (120 mM), valinomycin was more potent than cereulide both as ionophore and inhibitor, but at low [KCl] (2.5 mM), cereulide was much more potent. Thus, valinomycin needed 20-30 mM KCl for substantial effects, cereulide only 1-3 mM K+, which is close to its level in blood serum. This explains the higher toxicity of cereulide at low concentrations with the positively charged potassium complex being accumulated in the cell by transport through the plasma membrane driven by the membrane potential. Furthermore, with similar concentrations, the final concentration of cereulide in the cells may become higher than that of valinomycin. 相似文献
106.
Tiikkainen M Häkkinen AM Korsheninnikova E Nyman T Mäkimattila S Yki-Järvinen H 《Diabetes》2004,53(8):2169-2176
Both rosiglitazone and metformin increase hepatic insulin sensitivity, but their mechanism of action has not been compared in humans. The objective of this study was to compare the effects of rosiglitazone and metformin treatment on liver fat content, hepatic insulin sensitivity, insulin clearance, and gene expression in adipose tissue and serum adiponectin concentrations in type 2 diabetes. A total of 20 drug-naive patients with type 2 diabetes (age 48 +/- 3 years, fasting plasma glucose 152 +/- 9 mg/dl, BMI 30.6 +/- 0.8 kg/m2) were treated in a double-blind randomized fashion with either 8 mg rosiglitazone or 2 g metformin for 16 weeks. Both drugs similarly decreased HbA1c, insulin, and free fatty acid concentrations. Body weight decreased in the metformin (84 +/- 4 vs. 82 +/- 4 kg, P < 0.05) but not the rosiglitazone group. Liver fat (proton spectroscopy) was decreased with rosiglitazone by 51% (15 +/- 3 vs. 7 +/- 1%, 0 vs. 16 weeks, P = 0.003) but not by metformin (13 +/- 3 to 14 +/- 3%, NS). Rosiglitazone (16 +/- 2 vs. 20 +/- 1 ml.kg(-1).min(-1), P = 0.02) but not metformin increased insulin clearance by 20%. Hepatic insulin sensitivity in the basal state increased similarly in both groups. Insulin-stimulated glucose uptake increased significantly with rosiglitazone but not with metformin. Serum adiponectin concentrations increased by 123% with rosiglitazone but remained unchanged during metformin treatment. The decrease of serum adiponectin concentrations correlated with the decrease in liver fat (r = -0.74, P < 0.001). Rosiglitazone but not metformin significantly increased expression of peroxisome proliferator-activated receptor-gamma, adiponectin, and lipoprotein lipase in adipose tissue. In conclusion, rosiglitazone but not metformin decreases liver fat and increases insulin clearance. The decrease in liver fat by rosiglitazone is associated with an increase in serum adiponectin concentrations. Both agents increase hepatic insulin sensitivity, but only rosiglitazone increases peripheral glucose uptake. 相似文献
107.
Puomila A Huoponen K Mäntyjärvi M Hämäläinen P Paananen R Sankila EM Savontaus ML Somer M Nikoskelainen E 《Acta ophthalmologica Scandinavica》2005,83(3):337-346
PURPOSE: To assess the clinical picture and molecular genetics of 14 Finnish families with dominant optic atrophy (DOA). METHODS: The clinical status of family members was based on the assessment of visual acuity, colour vision, visual fields and optic nerve appearance; 31 individuals were affected, two suspect and 21 unaffected. A total of 30 coding exons and exon- intron boundaries of the OPA1 gene were sequenced in order to detect mutations. RESULTS: Half the patients were diagnosed at the age of < or = 20 years. Ten out of 20 affected individuals followed up for > or = 6 years had a progressive disease and 10 had a stable disease. According to WHO criteria, 36% of the affected patients were visually handicapped. Eight OPA1 pathogenic mutations, all but one novel, and 18 neutral polymorphisms were detected. CONCLUSION: The most sensitive indicators of DOA were optic disc pallor and dyschromatopsia. With molecular genetic analysis, asymptomatic mutation carriers and DOA cases with a mild clinical outcome were ascertained. No mutational hotspot or Finnish major mutation in the OPA1 gene could be demonstrated as most families carried a unique mutation. No obvious genotype- phenotype correlation could be detected. Detailed clinical assessment and exclusion of non-DOA families prior to mutation screening are necessary for obtaining a high mutation detection rate. 相似文献
108.
109.
Christoph Engel Christine Fischer Silke Zachariae Karolin Bucksch Kerstin Rhiem Jutta Giesecke Natalie Herold Barbara Wappenschmidt Verena Hübbel Monika Maringa Simone Reichstein-Gnielinski Eric Hahnen Claus R. Bartram Nicola Dikow Sarah Schott Dorothee Speiser Denise Horn Eva M. Fallenberg Marion Kiechle Anne S. Quante Anne-Sophie Vesper Tanja Fehm Christoph Mundhenke Norbert Arnold Elena Leinert Walter Just Ulrike Siebers-Renelt Stefanie Weigel Andrea Gehrig Achim Wöckel Brigitte Schlegelberger Stefanie Pertschy Karin Kast Pauline Wimberger Susanne Briest Markus Loeffler Ulrich Bick Rita K. Schmutzler 《International journal of cancer. Journal international du cancer》2020,146(4):999-1009
Comparably little is known about breast cancer (BC) risks in women from families tested negative for BRCA1/2 mutations despite an indicative family history, as opposed to BRCA1/2 mutation carriers. We determined the age-dependent risks of first and contralateral breast cancer (FBC, CBC) both in noncarriers and carriers of BRCA1/2 mutations, who participated in an intensified breast imaging surveillance program. The study was conducted between January 1, 2005, and September 30, 2017, at 12 university centers of the German Consortium for Hereditary Breast and Ovarian Cancer. Two cohorts were prospectively followed up for incident FBC (n = 4,380; 16,398 person-years [PY], median baseline age: 39 years) and CBC (n = 2,993; 10,090 PY, median baseline age: 42 years). Cumulative FBC risk at age 60 was 61.8% (95% CI 52.8–70.9%) for BRCA1 mutation carriers, 43.2% (95% CI 32.1–56.3%) for BRCA2 mutation carriers and 15.7% (95% CI 11.9–20.4%) for noncarriers. FBC risks were significantly higher than in the general population, with incidence rate ratios of 23.9 (95% CI 18.9–29.8) for BRCA1 mutation carriers, 13.5 (95% CI 9.2–19.1) for BRCA2 mutation carriers and 4.9 (95% CI 3.8–6.3) for BRCA1/2 noncarriers. Cumulative CBC risk 10 years after FBC was 25.1% (95% CI 19.6–31.9%) for BRCA1 mutation carriers, 6.6% (95% CI 3.4–12.5%) for BRCA2 mutation carriers and 3.6% (95% CI 2.2–5.7%) for noncarriers. CBC risk in noncarriers was similar to women with unilateral BC from the general population. Further studies are needed to confirm whether less intensified surveillance is justified in women from BRCA1/2 negative families with elevated risk. 相似文献
110.
Single trial fMRI reveals significant contralateral bias in responses to laser pain within thalamus and somatosensory cortices 总被引:8,自引:0,他引:8
Pain is processed in multiple brain areas, indicating the complexity of pain perception. The ability to locate pain plays a pivotal role in immediate defense and withdrawal behavior. However, how the brain localizes nociceptive information without additional information from somatotopically organized mechano-receptive pathways is not well understood. We used single-trial functional magnetic resonance imaging (fMRI) to assess hemodynamic responses to right and left painful stimulation. Thulium-YAG-(yttrium-aluminium-granate)-laser-evoked pain stimuli, without concomitant tactile component, were applied to either hand in a randomized order. A contralateral bias of the BOLD response was investigated to determine areas involved in the coding of the side of stimulation, which we observed in primary (SI) and secondary (SII) somatosensory cortex, insula, and the thalamus. This suggests that these structures provide spatial information of selective nociceptive stimuli. More importantly, this contralateral bias of activation allowed functionally segregated activations within the SII complex, the insula, and the thalamus. Only distinct subregions of the SII complex, the posterior insula and the lateral thalamus, but not the remaining SII complex, the anterior insula and the medial thalamus, showed a contralaterally biased representation of painful stimuli. This result supports the hypothesis that sensory-discriminative attributes of painful stimuli, such as those related to body side, are topospecifically represented within the forebrain projections of the nociceptive system and highlights the concept of functional segregation and specialization within these structures. 相似文献