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51.
52.
Background: Although internal cardioversion (IC) for atrial fibrillation (AF) is effective at restoring sinus rhythm, immediate recurrence (IR) of AF after IC is a major and largely unpredictable clinical problem. The purpose of the study was to determine the role of P wave duration and amplitude in prediction of IR of AF after IC. Forty‐five consecutive patients undergoing IC for chronic AF were evaluated. Material and Methods: After successful IC, 1‐minute ECG recording was obtained in all patients. P wave duration and amplitude in Lead II and V1 were measured using computer. Forty patients (88%) had successful IC. Thirteen patients experienced IR of AF within 1 minute of restoring sinus rhythm. Results and Conclusion: As a result, the incidence of IR of AF after IC was higher in the patients with shorter P wave amplitude (for lead II P < 0.01 , for V1P < 0.01 ) and larger P wave duration (for lead II P < 0.01 , for V1P < 0.05 ).  相似文献   
53.
The Xenopus oocyte is a very powerful tool for studies of the structure and function of membrane proteins, e.g., messenger RNA extracted from the brain and injected into oocytes leads to the synthesis and membrane incorporation of many types of functional receptors and ion channels, and membrane vesicles from Torpedo electroplaques injected into oocytes fuse with the oocyte membrane and cause the appearance of functional Torpedo acetylcholine receptors and Cl(-) channels. This approach was developed further to transplant already assembled neurotransmitter receptors from human brain cells to the plasma membrane of Xenopus oocytes. Membranes isolated from the temporal neocortex of a patient, operated for intractable epilepsy, were injected into oocytes and, within a few hours, the oocyte membrane acquired functional neurotransmitter receptors to gamma-aminobutyric acid, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, kainate, and glycine. These receptors were also expressed in the plasma membrane of oocytes injected with mRNA extracted from the temporal neocortex of the same patient. All of this makes the Xenopus oocyte a more useful model than it already is for studies of the structure and function of many human membrane proteins and opens the way to novel pathophysiological investigations of some human brain disorders.  相似文献   
54.
The aim of the study is to review the clinical manifestations and the hematological findings of brucellosis and pancytopenia, with or without hematological malignancies. The records of 202 patients with brucellosis were evaluated retrospectively. Among these cases of brucellosis seen in a 6 year period between April 1999 and June 2005, 30 patients with pancytopenia were identified. The most common manifestation was fever, followed by weight loss, anorexia, malaise, arthralgia, and hepatosplenomegaly. Bone marrow biopsies revealed hypercellularity or normocellularity. The most common findings in the bone marrow evaluation were histiocytic hemophagocytosis and granulomas. Among all cases, we diagnosed 5 hematological malignancies (1 acute myelogenous leukemia, 2 acute lymphoblastic leukemia, and 2 multiple myeloma) concurrently with brucellosis. The clinical symptoms and findings were similar in patients with and without malignancies. In cases with malignancies, the bone marrow biopsy revealed predominant primary disease involvement. Significant increases in ESR and CRP, severe anemia and thrombocytopenia were observed in patients with malignancies. Peripheral blood counts in patients without malignancies returned to normal after antibiotic treatment for brucellosis. However, pancytopenia in two patients with malignancies did not recover because of primary resistant disease. We conclude that while histiocytic hemophagocytosis may be considered as a major cause of pancytopenia, leukemic infiltration can also be an extreme and unusual cause of pancytopenia in patients in whom brucellosis was concurrently diagnosed with hematological malignancies.  相似文献   
55.
Transgenic plants overexpressing the vacuolar H(+)-pyrophosphatase are much more resistant to high concentrations of NaCl and to water deprivation than the isogenic wild-type strains. These transgenic plants accumulate more Na(+) and K(+) in their leaf tissue than the wild type. Moreover, direct measurements on isolated vacuolar membrane vesicles derived from the AVP1 transgenic plants and from wild type demonstrate that the vesicles from the transgenic plants have enhanced cation uptake. The phenotypes of the AVP1 transgenic plants suggest that increasing the vacuolar proton gradient results in increased solute accumulation and water retention. Presumably, sequestration of cations in the vacuole reduces their toxic effects. Genetically engineered drought- and salt-tolerant plants could provide an avenue to the reclamation of farmlands lost to agriculture because of salinity and a lack of rainfall.  相似文献   
56.

Background:

Vesicoureteral reflux (VUR) is a common abnormality of the urinary tract in childhood.

Objectives:

As urine enters the ureters and renal pelvis during voiding in vesicoureteral reflux (VUR), we hypothesized that change in body water composition before and after voiding may be less different in children with VUR.

Patients and Methods:

Patients were grouped as those with VUR (Group 1) and without VUR (Group 2). Bioelectric impedance analysis was performed before and after voiding, and third space fluid (TSF) (L), percent of total body fluid (TBF%), extracellular fluid (ECF%), and intracellular fluid (ICF%) were recorded. After change of TSF, TBF, ECF, ICF (ΔTSF, ΔTBF%, ΔECF%, ΔICF%), urine volume (mL), and urine volume/body weight (mL/kg) were calculated. Groups 1 and 2 were compared for these parameters. In addition, pre- and post-voiding body fluid values were compared in each group.

Results:

TBF%, ECF%, ICF%, and TSF in both pre- and post-voiding states and ΔTBF%, ΔECF%, ΔICF%, and ΔTSF after voiding were not different between groups. However, while post-voiding TBF%, ECF% was significantly decreased in Group 1 (64.5 ± 8.1 vs 63.7 ± 7.2, P = 0.013 for TBF%), there was not post-voiding change in TSF in the same group. On the other hand, there was also a significant TSF decrease in Group 2.

Conclusions:

Bladder and ureter can be considered as the third space. Thus, we think that BIA has been useful in discriminating children with VUR as there was no decreased in patients with VUR, although there was decreased TSF in patients without VUR. However, further studies are needed to increase the accuracy of this hypothesis.  相似文献   
57.
Purpose: To investigate the psychometric properties of the Persian version of Caregiver Burden Scale (CBS) in caregivers of patients with spinal cord injury.

Methods: This is a cross-sectional study. After a forward–backward translation, the CBS was administered to 110 caregivers of patients with spinal cord injury (men?=?60, women?=?50). Factor structure was evaluated by confirmatory factor analysis. The Internal consistency and test–retest reliability of the CBS were examined using Cronbach’s α and the intraclass correlation coefficient, respectively. Construct validity was assessed by examining the relationship among CBS and the World Health Organization Quality of Life, and the Beck Depression Inventory.

Results: The results of confirmatory factor analysis provided support for a five-factor model of CBS. All subscales of CBS revealed acceptable internal consistency (0.698–0.755), except for environment subscale (0.559). The CBS showed adequate test–retest reliability for its subscales (0.745–0.900). All subscales of CBS significantly correlated with both Beck Depression Inventory and World Health Organization Quality of Life, confirming construct validity.

Conclusions: The Persian version of the CBS is a valid and reliable measure for assessing burden of care in caregivers of patients with spinal cord injury.
  • Implications for Rehabilitation
  • Spinal cord injury leads to depression, high levels of stress and diminished quality of life due to the high physical, emotional, and social burdens in caregivers.

  • Persian version of the Caregiver Burden Scale is a valid and reliable tool for assessing burden in Iranian caregivers of patients with spinal cord injury.

  相似文献   
58.

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by arterial and/ or venous thrombosis accompanied by persistently elevated levels of antiphospholipid antibodies (aPLs). The aim of this study is to evaluate the pulmonary manifestations of APS and compare the levels of aPLs in patients with and without pulmonary involvement. We retrospectively reviewed the files of patients with the diagnosis of APS between October 2010 and May 2017. Demographic data, clinical, radiological and laboratory findings were recorded. The study included 67 patients (56 female/11 male) with a mean age of 39?±?13 years. Pulmonary manifestations such as parenchymal and/or vascular involvement were seen in 12 (17.9%) patients. The patients with and without pulmonary manifestations were not significantly different in terms of age (p?=?0.46), comorbidities (p?=?0.48) and APS duration (p?=?0.66). Acute pulmonary thromboembolism (PE) was determined in 11 (16.4%), alveolar hemorrhage in 2 (3%) patients. Four patients with acute PE (36%) developed chronic thromboembolic pulmonary hypertension (CTEPH). One patient developed both CTEPH and diffuse alveolar hemorrhage after acute PE during follow up. Antiphosholipid antibody IgM was highly positive in patients with PE compared to patients without PE (p?=?0.005). Other antibodies and lupus anticoagulant were not significantly different in patients with and without PE. None of the patients were deceased due to pulmonary manifestations of APS. PE was the most common pulmonary manifestation of APS. The development of CTEPH was high among APS patients. Patients with APS should be closely followed for the onset of PE and CTEPH.

  相似文献   
59.
Clinical Rheumatology - Immunoglobulin A vasculitis (IgAV) is the most common form of childhood systemic vasculitis. It is mostly self-limiting and characterized by skin, joint, gastrointestinal...  相似文献   
60.
Diaphragmatic hernias are the most common abnormalities of gastrointestinal system especially in elderly patients. The radiographic findings of diaphragmatic hernias on esophagram are well known, but when incidentally found in an asymptomatic patient on axial computed tomography (CT) sections, the appearance of diaphragmatic hernia may mimic many other conditions. Our purpose is to present the CT findings of sliding hernia in an incidentally found asymptomatic patient, and to differentiate it from the other abnormalities that can be located in the distal paraesophageal area with the same appearance characteristics.  相似文献   
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