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941.
An autoregulation-oriented strategy has been proposed to guide neurocritical therapy toward the optimal cerebral perfusion pressure (CPPOPT). The influence of ventilation changes is, however, unclear. We sought to find out whether short-term moderate hypocapnia (HC) shifts the CPPOPT or affects its detection. Thirty patients with traumatic brain injury (TBI), who required sedation and mechanical ventilation, were studied during 20?min of normocapnia (5.1±0.4?kPa) and 30 min of moderate HC (4.4±3.0?kPa). Monitoring included bilateral transcranial Doppler of the middle cerebral arteries (MCA), invasive arterial blood pressure (ABP), and intracranial pressure (ICP). Mx -autoregulatory index provided a measure for the CPP responsiveness of MCA flow velocity. CPPOPT was assessed as the CPP at which autoregulation (Mx) was working with the maximal efficiency. During normocapnia, CPPOPT (left: 80.65±6.18; right: 79.11±5.84?mm Hg) was detectable in 12 of 30 patients. Moderate HC did not shift this CPPOPT but enabled its detection in another 17 patients (CPPOPT left: 83.94±14.82; right: 85.28±14.73?mm Hg). The detection of CPPOPT was achieved via significantly improved Mx-autoregulatory index and an increase of CPP mean. It appeared that short-term moderate HC augmented the detection of an optimum CPP, and may therefore usefully support CPP-guided therapy in patients with TBI.  相似文献   
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946.
We investigated in vivo the relationship between the degree of peripheral blood lymphocyte apoptosis and circulating dendritic cells (DC) as well as the immunological status in 45 patients with systemic lupus erythematous (SLE). Apoptosis was detected by phosphatidylserine externalization and assays to detect caspase activation. The total DC count (tDC) and their myeloid, mDC1 (BDCA1+) and mDC2 (BDCA3+), and plasmacytoid, pDC (BDCA3+), subtypes were assessed. Moreover, several immunological parameters, such as complement proteins, interferons (IFN), tumor necrosis factor (TNF)-, interleukin (IL)-4, and IL-6 levels were assessed. There were no significant differences in both the intensity of apoptosis and DC counts between active and inactive SLE as well as between untreated patients and those treated with steroids. The incidence of lymphocyte apoptosis correlated positively with T-cell count, both T-helper (p=0.004) and cytotoxic T cells (p=0.001), but not with B or natural killer (NK) cells. The intensity of apoptosis enhanced along with the increase in complement C3 (p=0.016) and decrease in IFN- (p=0.040) levels. The apoptotic cell count correlated with tDC (p=0.031), mDC1 (p=0.007), and pDC (p=0.039) counts. Both tDC and mDC1 counts correlated positively with antinuclear antibody (ANA) titers (p=0.017 and 0.032, respectively). Moreover, tDC correlated with C4 (p=0.039) and pDC with both C3 (p=0.032) and C4 (p=0.007) levels. The DC counts correlated inversely with IFN- (tDC, p=0.038; mDC1, p=0.009), IL-6 (mDC2, p=0.031), or serum IgG levels (tDC, p=0.006; mDC1, p<0.001; mDC2, p=0.001). We found a positive correlation between lymphocyte apoptosis and peripheral blood DC count as well as the level of complement proteins in patients with SLE. The enhanced lymphocyte apoptosis was accompanied by the decrease in concentration of some cytokines, such as IFN- or IL-6, as well as serum IgG level. This finding may reflect pathogenetic events during development of the disease, which include a persistent signal derived from circulating apoptotic lymphocytes, mobilizing the complement system, and attracting peripheral blood DC.  相似文献   
947.
AIMS: The high-sensitivity C-reactive protein (hs-CRP) measurement is recommended by ESC/ESH Guidelines 2003 in patients with arterial hypertension. The aim of this study was to assess distribution of hs-CRP in Poland, a country representing a high-risk region for CVD. METHODS AND RESULTS: In 2002, the cross-sectional survey NATPOL PLUS was performed in a representative sample of adults in Poland aged 18-94 years. The questionnaire, anthropometrical and blood pressure measurements, glycaemia, lipidogram and hs-CRP were performed in 2333 respondents. The results of hs-CRP > 10 mg/l were excluded from analysis. Mean hs-CRP was 2.03+/-2.14 mg/l (2.13+/-2.12 mg/l in women vs 1.91+/-2.16 mg/l in men; p < 0.05). Hs-CRP > or = 1 mg/l was observed in 58% of women and in 52% of men (p < 0.05). In hypertensives (> or =140/90 mmHg or treatment: women 30% vs men 29%, ns.), hs-CRP > or = 1 mg/l was found in 74% of women, and in 63% of men. The transformed values of hs-CRP [-1/[hs-CRP](1/2)] were higher in hypertensive patients than in normotensives (-0.94 vs -1.05; p < 0.01). CONCLUSION: (i) The increased level of hs-CRP was found in more than half of adults in Poland. (ii) The hs-CRP is higher in hypertensive patients than in normotensives. (iii) In view of the given results, routine measurements of hs-CRP in hypertensive patients in a country like Poland should be reconsidered.  相似文献   
948.
Renal osteodystrophy is a common complication of chronic renal failure and renal replacement therapy. The purpose of the study was to assess whether hemodialysis (HD) or hemodiafiltration (HDF) affects bone turnover. In all, 45 HD and 17 HDF patients were evaluated with respect to bone metabolism markers. We assessed PTH; markers of bone formation-alkaline phosphatase and its bone isoform, osteocalcin; markers of bone resorption- PICP, ICTP; Ctx; beta2-microglobulin; and urinary DPD. BMD were determined for femoral neck and lumbar spine (L2-L4) using DEXA. Hemodialyzed patients had lower calcidiol, calcitriol, and BMD in the femur neck, and higher phosphate, Kt/V, residual renal function, venous pH, osteocalcin, ALP, bALP, DPD, beta2-microglobulin, ICTP, Ctx, osteoprotegerin, and RANKL than patients on HDF. HDF seems to ameliorate bone metabolism in comparison with HD. Bone turnover in end-stage renal failure might be affected to some extent by the choice of renal replacement therapy.  相似文献   
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The aim of this study was to prospectively investigate the spermatozoa ultrastructure in relation to the results of in vitro fertilization-embryo transer (IVF-ET). Forty-nine consecutive couples admitted for IVF-ET were prospectively evaluated for electron microscopic spermatozoa morphology and the outcome of IVF-ET. Thirty-four couples revealed successful fertilization, defined as presence of two pronuclei 14-16 hours after spermatozoa administration, while the remaining 15 formed the failure group. Spermatozoa fixed with 2.5% glutaraldehyd and embedded in Spurr's resin were analyzed with JAM 100 S transmission electron microscope (TEM) for the following ultrastructure abnormalities: head deformity, cytoplasmic residues, chromatin condensation failures, acrosomal alterations, neck defects, mid-piece defects, principal piece and end-piece defects and immature forms. Successful IVF-ET couples revealed a significantly higher percentage of normal spermatozoa utrastructure (32.0 +/- 13.1% versus 17.1 +/- 13.4%, p < 0.001). Failed IVF-ET couples represented a significantly higher percentage of chromatin condensation failures (9.8 +/- 5.1% versus 5.7 +/- 5.3%, p < 0.05) and tail defects (16.7 +/- 11.5% versus 7.2 +/- 7.2%, p < 0.001). A positive correlation between normal ultrastructure spermatozoa percentage and fertilized oocytes percentage was found (r = 0.35, p < 0.05). Our data suggest that spermatozoa TEM findings correlate with IVF-ET results. Ultrastructural estimation of spermatozoa can improve the diagnosis of male fertility and may explain some reasons of failure in assisted reproduction methods. We consider systematic TEM spermatozoa examination in cases with failed IVF-ET prior to intracytoplasmic sperm injection (ICSI).  相似文献   
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