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81.
The physico-chemical water characteristics and basin morphology of 10 well-preserved Pomeranian peatland lakes were examined. These are acidic (pH 3.95–5.99), softwater (1.5 ±0.9 mg Ca dm?3), and oligotrophic water bodies. Their hydrochemical conditions differentiate them into two groups: poor (3.04 ±2.77 mg C dm?3) and rich (10.36 ±7.27 mg C dm?3) in organic carbon compounds. They differ in water colour (p = 0.02), humic acid concentration (p<0.001), redox potential (p = 0.007), and irradiance (PAR; p = 0.03). The hydrochemistry of the lakes is determined by their basin morphology, which affects the water colour and the concentrations of humic acids and organic carbon compounds.  相似文献   
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ObjectiveTo investigate the effect of variable tricuspid annular reduction (TAR) on functional tricuspid regurgitation (FTR) and right ventricular (RV) dynamics in ovine tachycardia-induced cardiomyopathy.MethodsNine adult sheep underwent implantation of a pacemaker with an epicardial lead and were paced at 200 to 240 bpm until the development of biventricular dysfunction and functional TR was noted. During reoperation on cardiopulmonary bypass, 6 sonomicrometry crystals were placed around the tricuspid annulus (TA) and 14 were placed on the RV epicardium. Annuloplasty suture was placed around the TA and externalized to an epicardial tourniquet. After weaning from cardiopulmonary bypass, echocardiographic, hemodynamic, and sonomicrometry data were acquired at baseline and during 5 progressive TARs achieved with suture cinching. TA area and RV free wall strains and function were calculated from crystal coordinates.ResultsAfter pacing, changes in left ventricular (LV) ejection fraction and RV fractional area decreased significantly. Mean TA diameter increased from 25.1 ± 2.9 mm to 31.5 ± 3.3 mm (P = .005), and median TR (range, 0-3+) increased from 0 (0) to 3 (2) (P = .004). Progressive suture cinching reduced the TA area by 18 ± 6%, 38 ± 11%, 56 ± 10%, 67 ± 9%, and 76 ± 8%. Only aggressive annular reductions (67% and 76%) decreased TR significantly, but these were associated with deterioration of RV function and strain. A moderate annular reduction of 56% led to a substantial reduction of TR with little deleterious effect on regional RV function.ConclusionsA moderate TAR of approximately 50% may be most advantageous for correction of functional TR and simultaneous maintenance of regional RV performance. Additional subvalvular interventions may be needed to achieve complete valvular competence.  相似文献   
84.
Objective

To determine frequencies, interlaboratory reproducibility, clinical ratings, and prognostic implications of neural antibodies in a routine laboratory setting in patients with suspected neuropsychiatric autoimmune conditions.

Methods

Earliest available samples from 10,919 patients were tested for a broad panel of neural antibodies. Sera that reacted with leucine-rich glioma-inactivated protein 1 (LGI1), contactin-associated protein-2 (CASPR2), or the voltage-gated potassium channel (VGKC) complex were retested for LGI1 and CASPR2 antibodies by another laboratory. Physicians in charge of patients with positive antibody results retrospectively reported on clinical, treatment, and outcome parameters.

Results

Positive results were obtained for 576 patients (5.3%). Median disease duration was 6 months (interquartile range 0.6–46 months). In most patients, antibodies were detected both in CSF and serum. However, in 16 (28%) patients with N-methyl-d-aspartate receptor (NMDAR) antibodies, this diagnosis could be made only in cerebrospinal fluid (CSF). The two laboratories agreed largely on LGI1 and CASPR2 antibody diagnoses (κ = 0.95). The clinicians (413 responses, 71.7%) rated two-thirds of the antibody-positive patients as autoimmune. Antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), NMDAR (CSF or high serum titer), γ-aminobutyric acid-B receptor (GABABR), and LGI1 had ≥ 90% positive ratings, whereas antibodies against the glycine receptor, VGKC complex, or otherwise unspecified neuropil had ≤ 40% positive ratings. Of the patients with surface antibodies, 64% improved after ≥ 3 months, mostly with ≥ 1 immunotherapy intervention.

Conclusions

This novel approach starting from routine diagnostics in a dedicated laboratory provides reliable and useful results with therapeutic implications. Counseling should consider clinical presentation, demographic features, and antibody titers of the individual patient.

  相似文献   
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86.
Background and aimsCholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) are crucial proteins in reverse cholesterol transport. There are insufficient data on regulating these proteins by insulin therapy in type 1 diabetes mellitus (T1DM). We aimed to assess prospectively the impact of insulin therapy initiation on transfer proteins serum levels in adults with newly diagnosed T1DM.Methods and results57 adults with newly diagnosed T1DM were enrolled in the InLipoDiab1 Study. All participants were treated with subcutaneous insulin in the model of intensive insulin therapy since the diagnosis of diabetes. Serum PLTP and CETP concentrations were measured at diagnosis, after three weeks, six months, and after one year of insulin treatment, using the immunoenzymatic method ELISA.A significant decrease in PLTP and CETP concentrations were demonstrated during twelve months of insulin therapy in newly diagnosed T1DM. The dynamics of changes in the level of these proteins varied depending on the occurrence of remission after a year of the disease. In the group without remission, a significant decrease in PLTP and CETP levels appeared after six months of follow-up. The remission group was characterized by a decrease in proteins concentration only after one year of treatment. In the non-remission group, significant negative correlations were found between the daily dose of insulin and levels of PLTP and CETP.ConclusionExogenous insulin is an inhibitor of lipid transfer proteins involved in high-density lipoprotein cholesterol metabolism in the first year of treatment.  相似文献   
87.
88.
Summary The diagnostic value of oesophageal echocardiography is most striking in patients in whom precordial studies are of inadequate quality or fail to establish a definitive diagnosis. Oesophageal studies have excellent image quality, can be completed within 10 minutes without complications and, in most instances, enables the clinical question to be answered. In 50 patients referred for suspected thoracic aorta pathology, oesophageal echocardiography correctly excluded or diagnosed the type of aortic dissection, aortic aneurysm or the site of coarctation. Of 35 patients referred with suspected infective endocarditis, oesophageal echocardiography revealed complications in 18 patients, including vegetation, mycotic aneurysm, abscess or chordal rupture. Oesophageal echocardiography is extremely helpful to visualize intracardiac mass lesions. In 27 patients with a history of systemic or pulmonary embolism, the technique confirmed the presence, size and position of a mass lesion in 11 patients. Oesophageal color Doppler flow imaging further expands the diagnostic capabilities, particularly in patients with mitral valve prosthesis. Our experience indicates that oesophageal echocardiography significantly extends the diagnostic potential of echocardiography. Detailed knowledge of cardiothoracic anatomy and its pathologic sequelae is, however, a prerequisite for the efficient and safe application of this method.  相似文献   
89.
90.
OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis.  相似文献   
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