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1.
Although hepatitis E virus (HEV) is the primary cause of enterically transmitted acute hepatitis and jaundice in developing countries, locally acquired HEV infections are increasing in nonendemic countries. As such, HEV is emerging as an underdiagnosed cause of infection. This report describes three clinically variable cases of HEV infection with unusual clinical presentations. These cases highlight the fact that HEV should be considered in the differential diagnosis of patients with unexplained hepatitis (acute or chronic) with or without extrahepatic manifestations. HEV should also be considered in patients with persistently elevated liver enzymes who have not travelled to known HEV-endemic regions. Lack of knowledge among physicians and an absence of standardized diagnostic tests may result in increased morbidity and mortality from HEV infection.  相似文献   
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A temperature probe based on the magnetic resonance properties of an encapsulated liquid crystal has been investigated. Large changes in magnetic resonance signals occur as the liquid crystal undergoes a phase transition from an anisotropic (nematic) state to the isotropic liquid. The low latent heat of such phase transitions allows for rapid phase changes during a hyperthermia treatment. Transition temperatures can be tailored by adding suitable compounds such as analogues of the liquid crystal or various solvents. Encapsulation is required to maintain the integrity of the liquid crystal, particularly for applications in vivo. Results of preliminary studies designed to demonstrate the technical feasibility of the concept are presented.  相似文献   
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The endoscopic spectrum of primary non-Hodgkin's lymphoma of the stomach   总被引:1,自引:0,他引:1  
Thirty-one consecutive patients with primary non-Hodgkin's lymphoma of the stomach were studied to outline the spectrum of endoscopic abnormalities. The 17 men and 14 women had a median age of 65 years. There were 22 patients in stage I and 9 in stage II. Three endoscopic patterns were recognized: diffuse infiltration (9), ulceration (9) and polypoid lesions (13). There was no apparent correlation between the endoscopic appearance and the grading or subtype of the malignancy. Local recurrence did not occur once complete remission was obtained. The disease-free 5-year survival rate was 45%. Recognition of these endoscopic patterns may lead to earlier detection and, hopefully, improved survival.  相似文献   
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Two siblings from a consanguineous family presented with a poikiloderma of limbs and face, plantar keratoderma, and toenail pachyonychia. Neutropenia and neutrophil dysfunction with impairment of the respiratory burst and bacterial killing resulted in frequent respiratory tract infections. A bronchocentric granulomatous pneumonia was a fatal complication. The clinical presentation is consistent with Clericuzio type poikiloderma with neutropenia. Literature review identified several additional probable patients. Genetic linkage analysis excluded the locus of the RECQL4 gene, mutations in which have been described in some patients with the Rothmund-Thomson poikiloderma syndrome. This report confirms the clinical and genetic identity of the Clericuzio type of poikiloderma with neutropenia syndrome.  相似文献   
7.
Mice homozygous for the disrupted type-II Na/P(i) cotransporter gene ( Npt2(-/-)) exhibit hypophosphataemia, increased serum concentration of 1,25-dihydroxyvitamin D (1,25-(OH)(2)D) and calcium (Ca) and elevated urinary Ca excretion. To determine whether the hypercalcaemia and hypercalciuria are secondary to 1,25-(OH)(2)D-stimulated intestinal Ca absorption, we examined the effect of Npt2 gene disruption on serum Ca and urinary Ca excretion after an overnight fast, and on duodenal Ca absorption. We also compared the duodenal expression of the epithelial Ca channels, ECaC1 and ECaC2, and calbindinD(9K) mRNAs, relative to that of beta-actin mRNA, in Npt2(+/+) and Npt2(-/-) mice. Both serum Ca and urine Ca/creatinine were significantly decreased in Npt2(-/-) mice after an overnight fast and were no longer different from that in wild-type mice. Absorption of (45)Ca from isolated duodenal segments in vivo and (45)Ca appearing in the plasma were significantly increased in Npt2(-/-) compared with Npt2(+/+) mice. In addition, the duodenal abundance of ECaC1, ECaC2 and calbindinD(9K) mRNAs was significantly elevated in mutant mice relative to that in wild-type mice. In contrast, both duodenal Ca absorption and ECaC1 and ECaC2 mRNA abundance were lower in mice with X-linked hypophosphataemia ( Hyp) than in normal littermates. In summary, we provide evidence for increased duodenal Ca absorption in Npt2(-/-) mice and suggest a role for ECaC1, ECaC2 and calbindinD(9K) in mediating this response.  相似文献   
8.
The aim of this study was to evaluate the lipoprotein profile in women with hyperprolactinaemic amenorrhoea and to establish whether effective dopamine agonist therapy might have a beneficial effect. Blood samples were collected from women with hyperprolactinaemic amenorrhoea and from controls matched for age, body mass index and smoking. Follow-up blood samples were collected from women on dopamine agonist therapy as treatment for their hyperprolactinaemia. Plasma cholesterol, high density lipoprotein cholesterol, low density lipoprotein (LDL) cholesterol, very low density lipoprotein cholesterol, triglycerides, serum oestradiol and prolactin were measured. No statistically significant differences were found in the lipoprotein profile of the patient (n = 15) and control (n = 15) groups. During treatment with the dopamine agonist, bromocriptine (n = 9), significant reduction in total cholesterol [4.87 (3.98-5.87) versus 5.60 (4.55-6.61) mmol/l, P = 0.024] and LDL cholesterol [3.22 (2.01-4.23) versus 3.72 (2.59-4.93) mmol/l, P = 0.033] was noted. We conclude that beneficial alterations in the lipoprotein profile may occur in response to effective dopamine agonist therapy, presumably as a consequence of return of ovarian function and alleviation of oestrogen deficiency. Women with hyperprolactinaemic amenorrhoea should be encouraged to take effective therapy to improve their lipoprotein profile and potentially reduce their cardiovascular risk.  相似文献   
9.
BACKGROUND: Enteroviruses (EV) and parechoviruses (HPeV) are the most common causes of aseptic meningitis, encephalitis and sepsis-like syndrome in neonates. Detection by nucleic acid amplification methods improves patient management. OBJECTIVE: Development of a real-time PCR assay on a LightCycler for simultaneous detection of EV, HPeV and an internal control to monitor inhibition. STUDY DESIGN: We investigated the value of the new assay, prospectively, in a variety of samples from patients suspected of having viral meningitis or sepsis-like syndrome. RESULTS: The assay detected 64 EV serotypes and HPeV types 1-4. Of 186 patients, 63 (33.9%) were EV positive and 18 (9.7%) HPeV positive in one or more samples. In 43 of 159 feces and 6 of 57 throat samples viral culture and PCR were positive. With real-time PCR 27 extra EV and 19 HPeV positives were found. Blood and CSF were present from 33 patients. In 19 patients blood and CSF were positive, one was only positive in CSF, two were only positive in blood, 11 were negative. From 96 patients CSF and/or blood samples were tested and compared to results in throat and/or feces samples. Forty patients were EV-PCR and 14 HPeV-PCR positive in blood and/or CSF. All of these were confirmed by a positive PCR for the respective virus in feces and/or throat. CONCLUSIONS: Simultaneous detection of EV and HPeV with this two-step real-time PCR is specific, faster and more sensitive than viral culture. All systemic infections (blood or CSF positive) were confirmed in feces. Culture is no longer necessary for clinical diagnosis and should only be performed on PCR-positive samples to obtain isolates for typing purposes. Application of this assay is an important improvement for patient management since the outcome of the analysis is available within the time frame of clinical decision-making.  相似文献   
10.
A method is described for assessing the lymphocyte transformation of human leucocyte cultures induced by phytohaemagglutinin (PHA) and tuberculin purified protein derivative (PPD) by the measurement of the uptake of [14C]thymidine. The thymidine uptake of the cultures has been expressed as percentage of the total activity added. The mean basal uptake of twenty-two unstimulated cultures was 0·96%. The mean uptake of twenty-four PHA stimulated cultures was 19·5%, whilst the mean uptake of eleven PPD stimulated cultures from seven subjects, who were strongly positive on skin testing to tuberculin, was 20·1%. A rise of thymidine uptake was detected in five out of six tuberculin negative subjects (mean uptake 3·8%). Hydrocortisone hemisuccinate in final concentrations of 5 and 50 μg/ml usually reduced the thymidine uptake of unstimulated and PHA and PPD stimulated cultures, though the total cell count was reduced in only four out of ten cultures. An increase of thymidine from 1 to 64 μg/culture resulted in twoto three-fold increase in the uptake of thymidine; further increase of thymidine added to the cultures to 256 μg/culture resulted in a decrease of thymidine uptake.  相似文献   
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