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81.
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ObjectiveWe tested the hypotheses that monthly fluctuations in markers of arterial stiffness and blood pressure hemodynamics differ between women with and without premenstrual syndrome. We also assessed hypertension prevalence and arterial stiffening in postmenopausal women with or without history of premenstrual symptoms.MethodsTwenty one pre-menopausal women with premenstrual syndrome and 15 women without were prospectively examined in three distinct phases of their menstrual cycle (menses, late follicular and luteal phase). Pulse-wave velocity and analysis were used to assess arterial stiffness and wave reflection indices, respectively. Endothelial function was evaluated by flow-mediated vasodilation. In a cross-sectional substudy, 156 postmenopausal women were assessed for possible associations between retrospectively reported PMS symptoms and hypertension.ResultsIn women with premenstrual syndrome, arterial stiffness significantly increased during the luteal and menses phase (late follicular: 6.48 ± 1.07, luteal: 7.1 ± 1.26, menstruation: 7.12 ± 1.19 m/s, p = 0.003), while blood pressure peaked at the menses phase. Significant interactions between PMS and changes in arterial stiffness and blood pressure but not endothelial function, were observed. Changes in PWV were significantly associated with concomitant changes in blood pressure, C-reactive protein and the severity of PMS symptoms. The prevalence of hypertension (20.9% vs. 40.9%, p = 0.041) and pulse-wave velocity values (8.64 ± 1.52 vs. 9.37 ± 1.1, p = 0.046) were higher in postmenopausal women with 7 or more reported PMS symptoms. Arterial stiffness differences remained significant after adjustment for confounding factors.ConclusionThese results imply that PMS may affect arterial stiffness and BP monthly variability. Whether PMS is associated with new onset hypertension later in life needs further evaluation.  相似文献   
83.
Although stress gated technetium-99m single-photon emission computed tomographic (SPECT) myocardial perfusion imaging (MPI) is useful in differentiating ischemic from nonischemic cardiomyopathy, its prognostic usefulness in this patient population is not well understood. Consecutive unique patients with suspected coronary artery disease who, for clinical indications, underwent technetium-99m rest and stress MPI demonstrating ejection fractions ≤40% by gated SPECT imaging were retrospectively identified. In addition to prescan variables, previously defined cutoffs for gated SPECT parameters using visual and standard 17-segment semiquantitative scoring were applied and related to the occurrence of cardiac death up to 5 years after MPI. Of the 475 patients fulfilling criteria for study inclusion, follow-up was complete in 444 (93%) over 3.7 ± 1.6 years. Of 393 patients without subsequent early (≤60 days) coronary revascularization, cardiac death occurred in 64 (16%). The summed stress score, an MPI measure of the extent and severity of coronary artery disease that also accounts for the ischemic burden, was the gated SPECT parameter most related to cardiac death with Kaplan-Meier 5-year cardiac death-free survival of 85.6% and 67.3% in patients with summed stress scores ≤8 and >8, respectively (p <0.001). In multivariate Cox regression analysis, a summed stress score >8 independently contributed to cardiac death (adjusted hazard ratio 2.20, 95% confidence interval 1.34 to 3.61), and its addition to the model significantly increased the global chi-square value over prescan variables (from 32.46 to 41.67, p = 0.002). In conclusion, stress MPI data from gated technetium-99m SPECT scans are useful for the prediction of cardiac death in patients with moderate to severe left ventricular systolic dysfunction in whom there is suspicion of underlying coronary artery disease.  相似文献   
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Introduction

Unconscious processing of words during general anaesthesia has been suggested. We used the process dissociation procedure (PDP) to test memory performance during sevoflurane and propofol anaesthesia in relation to hypnotic depth.

Material and methods

One hundred participants anaesthetised for elective surgery (50 with propofol and 50 with sevoflurane) and 50 non-anaesthetized listened to a list of words. The bispectral index (BIS) of the anaesthetised patients was recorded. Within 36 h after word presentation, memory was assessed using a word stem completion task, based on Buchner''s model applied on the PDP.

Results

There was evidence of memory for words presented during light (BIS 61-80) (p = 0.001) and adequate (BIS 41-60) (p = 0.008) but not deep anaesthesia (BIS 21-40) (p = 0.09). The PDP showed a significant implicit but not explicit memory contribution (mean total explicit memory scores: 0.04 ±0.07 in all BIS categories; mean implicit memory scores: 0.01 ±0.04, 0.1 ±0.08, and 0.05 ±0.09 at BIS = 21-40, 41-60, and 61-80, respectively). There was a statistically significant difference between the mean implicit memory score (I) of the propofol and sevoflurane group in the BIS category 41-60 in general (p = 0.016), and after incision (IA.I.) (p = 0.005) in particular, with propofol depressing I more than sevoflurane in both cases. Memory performance of nonanaesthetized participants was better, with a higher contribution of explicit and a comparable contribution of implicit memory.

Conclusions

During general anaesthesia, implicit memory persists even in adequate hypnotic states. Sevoflurane affects the implicit memory of adequately anaesthetised subjects less than propofol.  相似文献   
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88.
The testing of dried blood spots (DBSs) for human immunodeficiency type 1 (HIV-1) proviral DNA by PCR is a technology that has proven to be particularly valuable in diagnosing exposed infants. We implemented this technology for HIV-1 early infant diagnosis (EID) and HIV-1 RNA viral load determination in infants born of HIV-1-seropositive mothers from remote areas in Cameroon. The samples were collected between December 2007 and September 2010. Fourteen thousand seven hundred and sixty-three (14,763) DBS samples from infants born of HIV-positive mothers in 108 sites nationwide were tested for HIV. Of these, 1452 were positive on first PCR analyses (PCR1), giving an overall infection rate of 12.30%. We received only 475 DBS specimen for a second PCR testing (PCR2); out of these, 145 were positive. The median HIV-1 RNA viral load for 169 infant DBS samples tested was 6.85 log copies/ml, with values ranging from 3.37 to 8 log copies/ml. The determination of the viral load on the same DBS as that used for PCR1 allowed us to bypass the PCR2. The viral load values were high and tend to decrease with age but with a weak slope. The high values of viral load among these infants call for early and effective administration of antiretroviral therapy (ART). The findings from this study indicate that the use of DBS provides a powerful tool for perinatal screening programs, improvement on the testing algorithm, and follow-up during treatment, and thus should be scaled up to the entire nation.  相似文献   
89.
Haemoglobinopathies are the most common hereditary disorders in Greece. Although there is a successful national prevention program, established 35 years ago, there is lack of an official registry and collection of epidemiological data for haemoglobinopathies. This paper reports the results of the first National Registry for Haemoglobinopathies in Greece (NRHG), recently organized by the Greek Society of Haematology. NRHG records all patients affected by thalassaemia major (TM), thalassaemia intermedia (TI), "H" Haemoglobinopathy (HH) and sickle cell disease (SCD). Moreover, data about the annual rate of new affected births along with deaths, between 2000 and 2010, are reported. A total of 4,506 patients are registered all over the country while the number of affected newborns was significantly decreased during the last 3 years. Main causes for still having affected births are: (1) lack of medical care due to financial reasons or low educational level; (2) unawareness of time limitations for prenatal diagnosis (PD); due either to obstetricians' malpractice or to delayed demand of medical care of couples at risk; and (3) religious, social or bioethical reasons. Cardiac and liver disorders consist main causes for deaths while life expectancy of patients lengthened after 2005 (p < 0.01). The NRHG of patients affected by haemoglobinopathies in Greece provides useful data about the haemoglobinopathies in the Greek population and confirms the efficacy of the National Thalassaemia Prevention Program on impressively decreasing the incidence of TM and sickle cell syndromes.  相似文献   
90.
Thrombomodulin is a cell surface-expressed glycoprotein that serves as a cofactor for thrombin-mediated activation of protein C (PC), an event further amplified by the endothelial cell PC receptor. The PC pathway is a major anticoagulant mechanism that downregulates thrombin formation and hedges thrombus formation. The objectives of this review were to review recent findings regarding thrombomodulin structure, its involvement in the regulation of hemostasis and further discuss the implication, if any, of the genetic polymorphisms in the thrombomodulin gene in the risk of development of thrombosis. We performed a literature search by using electronic bibliographic databases. Although the direct evaluation of risk situations associated with thrombomodulin mutations/polymorphisms could be of clinical significance, it appears that mutations that affect the function of thrombomodulin are rarely associated with venous thromboembolism. However, several polymorphisms are reported to be associated with increased risk for arterial thrombosis. Additionally studies on knock out mice as well studies on humans bearing rare mutations suggest that thrombomodulin dysfunction may be implicated in the pathogenesis of myocardial infraction.  相似文献   
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