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841.
842.
Preeclampsia and fetal growth   总被引:10,自引:0,他引:10  
OBJECTIVE: To determine if the influence of preeclampsia on birth size varies with clinical manifestations of the disease, and to evaluate whether maternal factors, such as smoking, modify the effect of preeclampsia on fetal growth. METHODS: Among 12,804 deliveries in a population of approximately 239,000 over a 3-year period, 307 live singleton infants were born after preeclamptic pregnancies. We compared those with a sample of 619 control infants. Preeclampsia was defined as increased diastolic blood pressure (BP) (increase of at least 25 mmHg to at least 90 mmHg) and proteinuria after 20 weeks' gestation. Clinical manifestations were classified according to BP and proteinuria into subgroups of mild, moderate, or severe (including cases with eclampsia and hemolysis, elevated liver enzymes, low platelets [HELLP] syndrome) preeclampsia, and according to gestational age at onset, as early or late preeclampsia. Birth size was expressed as the ratio between observed and expected birth weights, and infants smaller than two standard deviations from expected birth weights were classified as small for gestational age (SGA). RESULTS: Preeclampsia was associated with a 5% (95% confidence interval [CI] 3%, 6%) reduction in birth weight. In severe preeclampsia, the reduction was 12% (9%, 15%), and in early-onset disease, birth weight was 23% (18%, 29%) lower than expected. The risk of SGA was four times higher (relative risk [RR] = 4.2; 95% CI 2.2, 8.0) in infants born after preeclampsia than in control pregnancies. Among nulliparas, preeclampsia was associated with a nearly threefold higher risk of SGA (RR = 2.8; 1.2, 5.9), and among paras, the risk of SGA was particularly high after recurrent preeclampsia (RR = 12.3; 3.9, 39.2). In relation to preeclampsia and maternal smoking, the results indicated that each factor might contribute to reduced growth in an additive manner. CONCLUSION: Severe and early-onset preeclampsia were associated with significant fetal growth restriction. The risk of having an SGA infant was dramatically higher in women with recurrent preeclampsia. Birth weight reduction related to maternal smoking appeared to be added to that caused by preeclampsia, suggesting that there is no synergy between smoking and preeclampsia on growth restriction.  相似文献   
843.
Patients with combined hyperlipemia have lipid abnormalities associated with an increased tendency to develop atherosclerosis and thrombosis. This tendency may be accelerated during postprandial hyperlipemia. In the present double-blind parallel study, 41 patients with combined hyperlipemia and serum triacylglycerols between 2.0 and 15.0 mmol/L and serum total cholesterol >5.3 mmol/L at the end of a 3-month dietary run-in period were treated with simvastatin at 20 mg/d for at least 10 weeks; patients were then randomized into 2 groups receiving simvastatin+omega-3 fatty acids at 3.36 g/d or placebo (corn oil) for an additional 5 weeks. Hemostatic variables that have been associated with increased thrombotic tendency were evaluated with subjects in the fasting state and during postprandial hyperlipemia before and after combined treatment. Supplementation of omega-3 fatty acid reduced tissue factor pathway inhibitor antigen (P<0.05) in the fasting state, reduced the degree of postprandial hyperlipemia (P<0.005), and reduced activated factor VII concentration appearing during postprandial hyperlipemia. In conclusion, omega-3 fatty acids given in addition to simvastatin to patients with combined hyperlipemia reduced the free tissue factor pathway inhibitor fraction in the fasting state and inhibited the activation of factor VII occurring during postprandial lipemia, thus representing a potential beneficial effect on the hemostatic risk profile in this patient group.  相似文献   
844.
PURPOSE: The aims of the study were to evaluate short-term effects on lower urinary tract symptoms and uroflowmetry and assess side effects of transurethral needle ablation of the prostate (TUNA). PATIENTS AND METHODS: Twenty-six men with a median age 68 years (range 53-77 years) were evaluated with symptom scores and voiding parameters before and at 3 and 12 months after TUNA. All treatments were performed in the outpatient department using topical anesthesia supplemented with sedoanalgesia. RESULTS: The International Prostate Symptom Score had decreased from 21.2 to 10.5 at 12 months postoperatively. Peak urinary flow was 10.9 mL/sec at baseline and was elevated to 13.7 mL/sec after 12 months. Residual urine volumes were unchanged. Postoperative urinary retention developed in 71% of the patients and had a mean duration of 6.3 (range 1-34) days. Postoperative perineal pain was noted by about half of the patients for the first 1 to 2 weeks. Painkillers were frequently used to reduce postoperative pain. CONCLUSIONS: Transurethral needle ablation is a safe procedure suitable for the outpatient clinic. After short-term follow-up, statistically and clinically significant effects were observed on symptoms and uroflow. Long-term follow-up is mandatory to define the future role of this therapy.  相似文献   
845.
Background Strokes resulting in cognitive and motor problems can be debilitating and prolong recovery. Risk of a second stroke occurs for 40% of all first-time stroke survivors within five years. Prism adaptation treatment (PAT) may simultaneously improve functions of both spatial and motor systems. This has not been studied with a cohort comprised of multiple strokes nor measured change using specific motor outcomes.

Objectives To determine the feasibility and effectiveness of using PAT to improve spatial and motor functions in stroke survivors with multiple strokes.

Method A prospective intervention with retrospective comparison. Thirteen participants from an inpatient rehabilitation facility (IRF) comprised the treatment group; 13 others who only received standard care comprised the comparison group. Treatment group tested on: 4 motor and 3 spatial outcome measures before and after the 10 PAT sessions. The comparison group tested on: 1 motor and 3 spatial measures before and after standard care.

Results Thirteen participants successfully completed the PAT. Both groups improved on measures of spatial neglect over time (p < .001), but the treatment group showed greater improvement on two subtests of spatial function (Behavior inattention test) (p = .001 &; p = .002). Similarly, both groups improved in motor function (Functional independence measure) (p < .001), although the treatment group’s improvement was not statistically significant against the comparison group (p = .853).

Conclusion PAT is a feasible treatment for stroke survivors with multiple strokes. PAT did improve spatial neglect function more than standard care, only at one level of analysis of standard paper and pencil measures. Further research is necessary.  相似文献   
846.
I Bechmann  G Mor  J Nilsen  M Eliza  R Nitsch  F Naftolin 《Glia》1999,27(1):62-74
Despite the mechanical blood-brain barrier, activated T-cells can cross brain vessels. Thus, the CNS is routinely surveyed by immune competent cells; yet the healthy brain is not a target of antigen-specific immune reactions. Therefore, mechanisms must exist to prevent brain-antigen-specific T-cells from inducing immune responses. Data indicate that activated T-cells entering the CNS may undergo apoptosis rather than leaving the brain to induce immune responses. Applying RT-PCR, Western-blots, and immunocytochemistry, we have demonstrated expression of the apoptosis-inducing protein Fas ligand on astrocytes and neurons of apparently normal rat and human brains. FasL-positive astrocytes were often situated in close vicinity to cerebral blood vessels in vivo and induced apoptosis of Fas expressing Jurkat cells in vitro. We propose that similar to other immune privileged organs FasL-induced apoptosis of activated T-cells in the brain protects the tissue from self damaging immune attacks by forming an immunological brain barrier.  相似文献   
847.
848.
An Indiana capacitor-manufacturing cohort (n=3,569) was exposed to polychlorinated biphenyls (PCBs) from 1957 to 1977. The original study of mortality through 1984 found excess melanoma and brain cancer; other studies of PCB-exposed individuals have found excess non-Hodgkin lymphoma and rectal, liver, biliary tract, and gallbladder cancer. Mortality was updated through 1998. Analyses have included standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) using rates for Indiana and the United States, standardized rate ratios (SRRs), and Poisson regression rate ratios (RRs). Estimated cumulative exposure calculations used a new job-exposure matrix. Mortality overall was reduced (547 deaths; SMR, 0.81; 95% CI, 0.7-0.9). Non-Hodgkin lymphoma mortality was elevated (9 deaths; SMR, 1.23; 95% CI, 0.6-2.3). Melanoma remained in excess (9 deaths; SMR, 2.43; 95% CI, 1.1-4.6), especially in the lowest tertile of estimated cumulative exposure (5 deaths; SMR, 3.72; 95% CI, 1.2-8.7). Seven of the 12 brain cancer deaths (SMR, 1.91; 95% CI, 1.0-3.3) occurred after the original study. Brain cancer mortality increased with exposure (in the highest tertile, 5 deaths; SMR, 2.71; 95% CI, 0.9-6.3); the SRR dose-response trend was significant (p=0.016). Among those working >or= 90 days, both melanoma (8 deaths; SMR, 2.66; 95% CI, 1.1-5.2) and brain cancer (11 deaths; SMR, 2.12; 95% CI, 1.1-3.8) were elevated, especially for women: melanoma, 3 deaths (SMR, 5.99; 95% CI, 1.2-17.5); brain cancer, 3 deaths (SMR, 2.87; 95% CI, 0.6-8.4). These findings of excess melanoma and brain cancer mortality confirm results of the original study. Melanoma mortality was not associated with estimated cumulative exposure. Brain cancer mortality did not demonstrate a clear dose-response relationship with estimated cumulative exposure.  相似文献   
849.
CONTEXT: The association between thyroid function and blood pressure is insufficiently studied. OBJECTIVE: The objective of the investigation was to study the association between TSH within the reference range and blood pressure. DESIGN AND SETTING: This was a cross-sectional, population-based study. SUBJECTS: A total of 30,728 individuals without previously known thyroid disease were studied. MAIN OUTCOME MEASURES: The main outcome measures were mean systolic and diastolic blood pressure and pulse pressure and odds ratio for hypertension (>140/90 mm Hg or current or previous use of antihypertensive medication), according to categories of TSH. RESULTS: Within the reference range of TSH (0.50-3.5 mU/liter), there was a linear increase in blood pressure with increasing TSH. The average increase in systolic blood pressure was 2.0 mm Hg [95% confidence interval (CI) 1.4-2.6 mm Hg] per milliunit per liter increase in TSH among men, and 1.8 mm Hg (95% CI 1.4-2.3 mm Hg) in women. The corresponding increase in diastolic blood pressure was 1.6 mm Hg (95% CI 1.2-2.0 mm Hg) in men and 1.1 mm Hg (95% CI 0.8-1.3 mm Hg) in women. Comparing TSH of 3.0-3.5 mU/liter (upper part of the reference) with TSH of 0.50-0.99 mU/liter (lower part of the reference), the odds ratio for hypertension was 1.98 (95% CI 1.56-2.53) in men and 1.23 (95% CI 1.04-1.46) in women. CONCLUSION: Within the reference range of TSH, we found a linear positive association between TSH and systolic and diastolic blood pressure that may have long-term implications for cardiovascular health.  相似文献   
850.

Objectives

To explore how apparent diffusion coefficients (ADCs) in malignant breast lesions are affected by selection of b values in the monoexponential model and to compare ADCs with diffusion coefficients (Ds) obtained from the biexponential model.

Methods

Twenty-four women (mean age 51.3 years) with locally advanced breast cancer were included in this study. Pre-treatment diffusion-weighted magnetic resonance imaging was performed using a 1.5-T system with b values of 0, 50, 100, 250 and 800 s/mm2. Thirteen different b value combinations were used to derive individual monoexponential ADC maps. All b values were used in the biexponential model.

Results

Median ADC (including all b values) and D were 1.04?×?10-3?mm2/s (range 0.82–1.61?×?10-3?mm2/s) and 0.84?×?10-3?mm2/s (range 0.17–1.56?×?10-3?mm2/s), respectively. There was a strong positive correlation between ADCs and Ds. For clinically relevant b value combinations, maximum deviation between ADCs including and excluding low b values (<100 s/mm2) was 11.8 %.

Conclusion

Selection of b values strongly affects ADCs of malignant breast lesions. However, by excluding low b values, ADCs approach biexponential Ds, demonstrating that microperfusion influences the diffusion signal. Thus, care should be taken when ADC calculation includes low b values.

Key Points

? Diffusion-weighted sequences are increasingly used in breast magnetic resonance imaging ? Diffusion-weighting (b) values strongly influence apparent diffusion coefficients of malignant lesions ? Exclusion of low b values reduces the apparent diffusion coefficient ? Flow-insensitive monoexponential apparent diffusion coefficients approach biexponential diffusion coefficients  相似文献   
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