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91.
BACKGROUND: Primary sclerosing cholangitis (PSC) confers a high risk of cholangiocarcinoma (CC) development. Since patients at risk of CC may be selected for early liver transplantation, it is a challenge to identify any predisposing factors. We compared the presentation and natural history of a large number of PSC patients with and without later CC development to identify features associated with risk of CC. METHODS: Clinical and laboratory data from presentation and follow-up were collected from 394 PSC patients from five European countries. The cohort included 48 (12.2%) patients with CC. RESULTS: CC was diagnosed within the first year after diagnosis of PSC in 24 (50%) cases and in 13 (27%) patients at intended liver transplantation. Jaundice, pruritus, abdominal pain and fatigue were significantly more frequent at diagnosis of PSC in the group that developed CC, but not after exclusion of cases diagnosed within the first year. Inflammatory bowel disease was diagnosed at least 1 year before PSC more often among patients with CC development than among those without (90% and 65%, respectively: P = 0.001). The duration of inflammatory bowel disease before diagnosis of PSC was significantly longer in patients who developed CC than in the remaining group (17.4 years and 9.0 years, respectively: P=0.009 in multivariate analysis). CONCLUSIONS: A high proportion of CC cases is diagnosed within the first year after diagnosis of PSC. A long history of inflammatory bowel disease is a risk factor for CC development.  相似文献   
92.
A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in conjunction with the oral administration, it resulted in a high level of the drug in the anterior chamber of the eye (which was 160% of the plasma drug level).  相似文献   
93.
Data are presented suggesting that intact Neurospora crassa mitochondria contain an enzyme complex incorporating five enzymes necessary for the biosynthesis of isoleucine and valine. The functional integrity and stability of the complex has been shown to be dependent on the metabolic state of the mitochondria. The complex has been solubilized by digitonin and has an approximate molecular weight of 400,000.  相似文献   
94.
Objectives: This study examined the relationship between baseline compensation use, activity limitations and cognitive impairment in persons who sustained moderate-to-severe acquired brain injury. Design: Randomized controlled clinical trial. Methods: A total of 22 individuals with medically documented brain injury and their family members completed a baseline assessment including measures of cognitive functioning (Repeatable Battery of Neuropsychological Assessment; RBANS), activity limitations (Neurobehavioural Functioning Inventory; NFI) and compensatory strategies use (Compensation Techniques Questionnaire; CTQ). There were no gender differences on measures of cognitive impairment, activity limitations or compensation use. Results: As predicted, cognitive impairment was not significantly associated with frequency of baseline compensation strategy use. Weaker word-list learning on RBANS was associated with greater family-reported memory problems on the NFI. Lower frequency of compensatory strategy use was correlated with greater patient-reported activity limitations on NFI, while it was not related to family ratings of activity limitations. After adjusting for history of depression and anxiety, baseline compensation use uniquely accounted for 16% of variance in predicting greater patient ratings of mood difficulties. Conclusions: Results indicate that, after acquired brain injury, baseline compensation use is more strongly associated with measures of activity limitations than is cognitive impairment.  相似文献   
95.
Glycogen-storage disease type II, also named Pompe disease, is caused by the deficiency of the enzyme acid alpha-glucosidase, which originates lysosomal glycogen accumulation leading to progressive neuromuscular damage. Early-onset Pompe disease shows a debilitating and frequently fulminating course. To date, more than 300 mutations have been described; the majority of them are unique to each affected individual. Most early-onset phenotypes are associated with frameshift mutations leading to a truncated alpha-glucosidase protein with loss of function. Founder effects are responsible from many cases from few highprevalence world regions. Herein we described two apparently unrelated cases affected with classical early-onset Pompe disease, both pertaining to a small region from Central Mexico (the State of San Luis Potosí), the same novel homozygous frameshift mutation at gene GAA (c.1987delC) was demonstrated in both cases. This GAA gene deletion implies a change of glutamine to serine at codon 663, and a new reading frame that ends after 33 base pairs, which leads to the translation of a truncated protein. This report contributes to widen the knowledge on the effect of pathogenic mutations in Pompe disease. Here we postulate the existence of a founder effect.Key words: Early-onset Pompe disease, Acid maltase deficiency, Founder effectGlycogen storage disease type II (Online Mendelian Inheritance in Man, OMIM, accession number 232300), also called Pompe disease, was described by Johannes C. Pompe in 1932. The disorder is caused by a deficiency of the enzyme acid alpha-glucosidase (acid maltase, EC 3.2.1.20, Swiss) which originates lysosomal glycogen accumulation leading to lysosomal swelling, cellular damage and dysfunction (1-3). Affected individuals develop progressive neuromuscular damage, showing a debilitating and frequently fulminating course on the classical, early-onset type of the disease. Other main findings are hypertrophic cardiomyopathy, hypotonia, hepatomegaly, macroglossia, feeding problems and breath difficulty. Currently it is recognized that the late form of Pompe disease has a very variable phenotype that can be confused with a wide range of neuromuscular, pulmonary and cardiovascular diseases with mild, moderate or severe symptoms that present either alone or combined (4-6).Pompe disease has an autosomal recessive inheritance and it is caused by more than 300 mutations that occur all over the gene coding for acid alpha-glucosidase (GAA) located at locus 17q25.2q25.3. The molecular phenomenon responsible of the different types of clinical expression occur by the presence of two either homozygous or compound heterozygous pathogenic mutations in early-onset Pompe cases, whereas late-onset Pompe have one variant and one pathogenic mutation (7). The majority of disease-causing mutations are unique; nonetheless, relatively frequent mutations have been described in certain populations with a possible founder effect traced from the original mutated carrier to the newly occurring cases. Affected cases have been described worldwide with a few high-prevalence regions like South-Africa, Taiwan and Holland (1, 8-10).Herein, we described two unrelated cases affected with classical early-onset Pompe disease, both pertaining to the same small Mexican region, with the same novel homozygous frameshift mutation at gene GAA (c.1987delC), identified by complete gene sequencing.  相似文献   
96.
Summary— In recent years, two key concepts having numerous interrelationships were advanced for the understanding of various cardiovascular diseases: the “endothelial dysfunction” and the “arterial remodelling”. Both endothelial dysfunction and arterial remodelling occur in various pathologies including essential hypertension, heart failure, atherosclerosis, restenosis after angioplasty, and pulmonary hypertension, and have modified the therapeutic approach by offering new pharmacological targets: specific receptors not only at the site of the vascular smooth muscle cells but also on the endothelial cells, growth factors that stimulate proliferation of smooth muscle, and receptors and enzymes of the extra-cellular matrix. Among the various substances under research, the present review will discuss angiotensin II receptor antagonists, endothelin receptor antagonists, nitrates-NO donors, potassium channel activators, and substances interfering with proteoglycans and other components of the extra-cellular matrix.  相似文献   
97.
We instilled naphazoline Hcl (0.1%), an imidazole derivative with preferential alpha-2 activity, in 17 eyes of 12 patients with myopathic ptosis due to involvement of the levator palpebrae superioris, in the attempt to selectively stimulate Müller's smooth muscle. Naphazoline significantly widened the palpebral fissure with little change in pupillary diameter and no significant change in ocular pressure, visual acuity and near point determination. However, a reduction of the effect, probably due to tachyphylaxis, was noticed when using naphazoline regularly several times a day for few weeks. In conclusion naphazoline has powerful cosmetical and functional effects in mild to moderate myopathic ptosis above all if taken occasionally.  相似文献   
98.
Human breast cancer in vivo: H-1 and P-31 MR spectroscopy at 1.5 T   总被引:3,自引:0,他引:3  
To assess the potential of in vivo magnetic resonance (MR) spectroscopy for breast cancer, hydrogen-1 and phosphorus-31 MR spectra of five malignant human breast tumors were compared with those of unaffected breast tissue. The water-to-fat ratio was high in the tumors (average, 2.2) but low in the unaffected tissue (average, 0.3). The P-31 spectrum of normal breast tissue showed low levels of phosphomonoesters (PMEs), inorganic phosphate, phosphodiesters (PDEs), and ATP. In addition, an intense phosphocreatine (PCr) signal was observed in breast tissue of young women: The relative intensities of the PCr and ATP signals had a mean value of 1.9. The tumor spectrum showed elevated levels of PMEs, Pi, and PDEs, while no PCr was seen (PCr/ATP less than 0.2). In two breast cancers treated with radiation therapy, resulting in a decrease of tumor volume of more than 50%, a similar change in the tumor P-31 spectrum was observed: An intense PCr signal developed (PCr/ATP = 1.1). Control experiments indicated that the appearance of PCr after radiation therapy was the result of a radiation-induced metabolic change in the tumor itself.  相似文献   
99.
100.
Sympathetic nervous control of cat ileocecal sphincter   总被引:1,自引:0,他引:1  
  相似文献   
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