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排序方式: 共有795条查询结果,搜索用时 31 毫秒
91.
92.
Avi Ben-Haroush Nir Melamed Reuven Mashiach Israel Meizner Yariv Yogev 《Journal of ultrasound in medicine》2008,27(7):1029-1032
OBJECTIVE: The purpose of this study was to assess the value of combining the sonographically estimated fetal weight (EFW) and amniotic fluid index (AFI) measured within 10 days of term delivery for prediction of macrosomia at birth. METHODS: Prospective sonographic fetal biometric measurements and delivery ward data of a single center, uploaded separately over a 4-year period, were retrospectively linked to yield an unselected sample of nondiabetic pregnancies with live-born term neonates. RESULTS: Of the 1925 pregnancies evaluated, 140 (7.2%) were macrosomic (birth weight > or =4000 g). The AFI was significantly higher in the macrosomic group (P < .001). On receiver operating characteristic curve analysis, the area under the curve was larger for predictions based on the EFW alone than on the AFI. An EFW of 4000 g or higher had a positive predictive value of 46.6% for macrosomia at birth. Use of the previously suggested combined EFW and AFI cutoffs of 3689 g and 119 mm, respectively, yielded a positive predictive value of 30.3%. CONCLUSIONS: Combined use of the EFW and AFI rather than the EFW alone does not improve prediction of macrosomia at birth. 相似文献
93.
Guttman-Yassky E Abada R Kra-Oz Z Sattinger J Perelman A Bergman R Sarid R 《Diagnostic microbiology and infectious disease》2007,57(4):387-392
Human herpesvirus 8 (HHV-8), also known as Kaposi sarcoma (KS)-associated herpesvirus, is causally implicated in all forms of KS, including the classic form. Our objective was to investigate the relationship between HHV-8 load in peripheral blood mononuclear cells (PBMCs) and the stage of the disease in classic KS (CKS) patients. HHV-8 loads were measured in 41 PBMC samples from CKS patients with different Krigel-based classification stages using a quantitative real-time polymerase chain reaction assay. Low HHV-8 DNA loads reaching a maximum of 75.5 copies/10(5) cells were detected in 73.2% of the patients. HHV-8 loads in patients with stages I and II were similarly distributed. An increased detection rate of HHV-8 DNA, although not statistically significant, was evident in patients diagnosed with CKS stages III and IV. We conclude that the measurements of HHV-8 load in PBMCs provide a limited correlation with the clinical stage of KS. 相似文献
94.
Shamgar L Ma L Schmitt N Haitin Y Peretz A Wiener R Hirsch J Pongs O Attali B 《Circulation research》2006,98(8):1055-1063
The slow IKS K+ channel plays a major role in repolarizing the cardiac action potential and consists of the assembly of KCNQ1 and KCNE1 subunits. Mutations in either KCNQ1 or KCNE1 genes produce the long-QT syndrome, a life-threatening ventricular arrhythmia. Here, we show that long-QT mutations located in the KCNQ1 C terminus impair calmodulin (CaM) binding, which affects both channel gating and assembly. The mutations produce a voltage-dependent macroscopic inactivation and dramatically alter channel assembly. KCNE1 forms a ternary complex with wild-type KCNQ1 and Ca(2+)-CaM that prevents inactivation, facilitates channel assembly, and mediates a Ca(2+)-sensitive increase of IKS-current, with a considerable Ca(2+)-dependent left-shift of the voltage-dependence of activation. Coexpression of KCNQ1 or IKS channels with a Ca(2+)-insensitive CaM mutant markedly suppresses the currents and produces a right shift in the voltage-dependence of channel activation. KCNE1 association to KCNQ1 long-QT mutants significantly improves mutant channel expression and prevents macroscopic inactivation. However, the marked right shift in channel activation and the subsequent decrease in current amplitude cannot restore normal levels of IKS channel activity. Our data indicate that in healthy individuals, CaM binding to KCNQ1 is essential for correct channel folding and assembly and for conferring Ca(2+)-sensitive IKS-current stimulation, which increases the cardiac repolarization reserve and hence prevents the risk of ventricular arrhythmias. 相似文献
95.
BACKGROUND: Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is the most common cause of hyponatremia in elderly hospitalized patients; however in many patients the etiology remains unclear even after routine investigations. OBJECTIVE: To report our experience of the association of hyponatremia and urinary retention in elderly hospitalized patients. PATIENTS: Six patients with hyponatremia and urinary retention who were admitted to the geriatric department in our hospital during a four-year period (2001-2004). RESULTS: The mean age of the patients was 85 years. The mean serum sodium level was 120 mEq/l, average volume of retained urine was 933 ml (range 500-1,500 ml). All patients underwent a comprehensive work-up seeking a possible cause for the hyponatremia. The diagnostic work-up was negative. In 5 of the patients the laboratory findings fulfilled the criteria for SIADH. In all patients hyponatremia resolved following urinary catheterization and fluid restriction. All patients made a complete recovery. CONCLUSIONS: Potentially, urinary retention by itself may cause hyponatremia. The possible mechanism for this is SIADH, triggered by bladder distention or pain due to bladder distention. Urinary catheterization may be the key to treatment in these cases of hyponatremia. 相似文献
96.
97.
Evgenia Greenbaum Arthur Furst Alexander Kiderman Brendon Stewart Reuven Levy Miriam Schlesinger Avraham Morag Zichria Zakay-Rones 《Vaccine》2002,20(7-8):1232-1239
Influenza morbidity affects entire populations, imposing an enormous burden in economic terms from working days lost. Protection afforded by current vaccines is often unsatisfactory and many individuals remain averse to injections. To counter these drawbacks, we tested an inactive intra-nasal trivalent influenza vaccine on 182 vaccinated and 92 placebo subjects in the community.On study completion 73 and 66% of the subjects were immune to the vaccine's two A strains, 40% (> or=1:40) and 65% (> or=1:20) to its B strain; 30-40% demonstrated a 4x hemagglutination inhibition (HAI) titer increase; GMT titers increased 2.2-2.5x. About 50% of those initially non-immune became immune. A local antibody response to the three vaccine strains was recorded in 31-44% of vaccinees in which 57, 68 and 54% exhibited a mucosal and/or serum antibody response to the A/Johannesburg, A/Nanchang and B/Harbin strains, respectively. A higher dose (40mg) of A/Johannesburg in the vaccine did not influence response.The new vaccine was safe, without side-effects, and offered reasonable protection after one dose. It could thus play an important role in increasing enrollment into immunization programs. 相似文献
98.
Cervical chondrocutaneous vestiges or remnants originate from anomalous development of the branchial arches in the fourth week of gestation. Owing to their relative rarity, published data of cervical chondrocutaneous vestiges remain scarce. We report on the diagnosis and associated anomalies of cervical chondrocutaneous vestiges in three fetuses. The association of cervical chondrocutaneous vestige with other anomalies emphasizes the importance of performing meticulous examination and biochemical marker analysis in affected cases. 相似文献
99.
Witz Misha Gepstein Reuven Paran Haim Shnaker Ali Lehmann Jonathan Gryton Igal Shabat Shay 《European spine journal》2006,15(5):650-652
The dilemma of how to treat penetrating wound injuries to the neck, which involve a combination of a common carotid artery rupture and a cervical spinal fracture, is presented in this case report.
相似文献100.
Heparanase and basic fibroblast growth factor are co-expressed in malignant mesothelioma 总被引:4,自引:0,他引:4
Davidson B Vintman L Zcharia E Bedrossian C Berner A Nielsen S Ilan N Vlodavsky I Reich R 《Clinical & experimental metastasis》2004,21(5):469-476
Heparanase is an endoglycosidase that degrades heparan sulfate (HS) in the extracellular matrix (ECM) and cell surfaces, and fulfills a significant role in cancer metastasis and angiogenesis. We evaluated the expression of heparanase and its possible association with the expression of angiogenic molecules in malignant mesothelioma (MM), and analyzed whether expression of these proteins is site-related (pleural vs peritoneal MM, solid lesions vs effusions). Sections from 80 MM (56 biopsies, 24 effusions) were analyzed for heparanase protein expression using immunohistochemistry (IHC). Sixty MM were of pleural origin, and 20 were peritoneal. Effusion specimens consisted of 6 peritoneal and 18 pleural effusions, while biopsies consisted of 14 peritoneal and 42 pleural lesions. Fifty-four specimens were additionally evaluated for expression of basic fibroblast growth factor (bFGF), interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) proteins using IHC. Microvessel density (MVD) was studied in 28 biopsies using an anti-CD31 antibody. mRNA expression of heparanase (HPSE-1), VEGF and the VEGF receptor KDR was analyzed in 23 effusions using RT-PCR. Heparanase protein expression was seen in 69/80 (86%) tumors. Of these, 35 showed combined membrane and cytoplasmic expression, 30 cytoplasmic expression, and four exclusively membrane expression. Both total (P= 0.001) and cytoplasmic (P = 0.002) expression was significantly higher in solid tumors compared to effusions. Protein expression of VEGF, IL-8 and bFGF was seen in 21/54 (39%), 22/54 (41%) and 44/54 (81%) specimens, respectively. Protein expression of bFGF was significantly higher in solid tumors (P 0.001) and correlated with heparanase expression (P = 0.005). HPSE-1 and VEGF mRNA expression was detected in all 23 effusions using RT-PCR, while KDR mRNA was found in 12/23 MM. KDR mRNA expression correlated with that of both HPSE-1 (P = 0.005) and VEGF (P = 0.001). Our results document frequent expression of heparanase in MM, in agreement with the biological aggressiveness of this tumor. The co-expression of heparanase with bFGF is in agreement with the role of the former in releasing bFGF from the ECM. The concomitant reduction in protein expression of both molecules in effusions as compared to solid tumors, supports the hypothesis of a reduced need for pro-angiogenic stimuli in effusions, and may aid in defining tumor progression in this setting. 相似文献