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991.
992.
Introduction: There is recent evidence that prophylaxis with 150?mg of aspirin given before 14–16 weeks significantly reduces preeclampsia rates and may improve pregnancy outcome. We conducted an observational study that investigates the effect of low-dose aspirin initiated early in pregnancy or in preconception on functional parameters assessed at 11–14 weeks.

Materials and methods: We have retrospectively selected 128 pregnant women that presented for the first trimester screening for aneuploidies between 11+0 and 13+6 weeks of gestation and received low-dose aspirin before 14 weeks. We excluded cases with an estimated high risk for early preeclampsia (cut-off?>?1:100). This group was matched to 1044 cases that did not receive aspirin in early pregnancy. We have selected for statistical analysis maternal parameters, ultrasound parameters (crown-rump length, nuchal translucency thickness, pulsatility index in uterine arteries – left, right, average and average uterine PI expressed in multiple of median (MoM)), first trimester maternal biochemical markers (free β hCG and PAPP-A expressed in MoM), and the calculated risk for early onset and late onset preeclampsia.

Results: The most common dosages of aspirin were 75?mg (77 cases) and 100?mg (32 cases). The most significant results are within the aspirin group. In the subgroup that received aspirin before 11 weeks (110 cases), irrespective of the dosage, the uterine blood flow is significantly improved (average uterine PI 1.7 compared with 2.22, p?p?>?.05, [(?0.65)???0.02] 95% CI). The estimated risk for both early and late onset preeclampsia in this group is reduced (1:2141 compared with 1:333 for early preeclampsia, p?p?Conclusion: Even though the results are not always statistically significant, they demonstrate that placentation parameters improve with higher doses of aspirin started before 11 weeks.  相似文献   
993.
994.
We investigated the effects of beta-estradiol on the locomotor behavior of female mice in a radial maze. Data comprising the total distance traveled during each arm entry were obtained from video records of six consecutive daily recording sessions. Distributions of these data were bimodal for both ovariectomized control and beta-estradiol-treated ovariectomized subjects. Data were fit with the sum of two gamma probability distributions. Three parameters of the analytic fits were useful for quantifying the effect of beta-estradiol on locomotor behavior: (i) the sampling distance (median of the total distance traveled during each arm entry in the short-distance peak of a bimodal distribution), (ii) the committed distance (median of the total per-arm-entry distance traveled in the long-distance peak), and (iii) the partition distance (distance represented by the minimum between the two peaks). Analysis showed that for sampling-distance arm entries beta-estradiol typically had little if any significant effect on female locomotor behavior, whereas it significantly increased the total distance traveled during committed-distance arm entries on the first 2 days of exposure to the empty maze. beta-Estradiol also increased the ability of females to discriminate between empty maze arms and arms that contained intact or castrated male mice and partially prevented loss of this capacity after removal of the males.  相似文献   
995.
From 2004 to 2005, 60%-72% of invasive Staphylococcus aureus isolates from Romanian hospitals were resistant to methicillin (methicillin-resistant S. aureus [MRSA]), the highest frequency for any European nation. Few reports, however, have addressed the molecular characteristics of S. aureus in Romania. In this study, we utilized spa typing, multilocus sequence typing, staphylococcal cassette chromosome mec (SCCmec) typing, dru typing, pulsed-field gel electrophoresis, and detection of virulence factors to characterize 146 S. aureus strains isolated from 2004 to 2005 at the Clinic County Hospital in Bra?ov. Antibiotic susceptibility patterns for all MRSA isolates and patient demographic data were also obtained. Fifty-six strains (38.4%) were determined to be MRSA by susceptibility testing and SCCmec typing. All MRSA strains were resistant to beta-lactams and tetracycline, but susceptible to nitrofurans, vancomycin, and clindamycin, with inducible clindamycin resistance in 23/28 clindamycin-sensitive/erythromycin-resistant isolates. Molecular typing identified 15 clonal backgrounds (CC 1, 5, 8, 8/239, 9, 15, 20, 22, 25, 30, 45, 80, 97, 101, and 121), only 4 of which were associated with MRSA (CC 1, 8/239, 30, and 80). Spa types 35 (t127, CC 1) and 351 (t030, CC 8/239) accounted for 27.4% and 21.9% of all S. aureus strains, respectively, and 19.6% and 57.1% of all MRSA strains. Both hospital-associated (SCCmec type III) and community-associated (SCCmec type IV) elements were identified within MRSA strains, whereas Panton-Valentine leukocidin was detected in 10 MRSA and 12 methicillin-sensitive S. aureus strains. These results demonstrate the presence of various endemic S. aureus clones within the Clinic County Hospital in Bra?ov, suggestive of ongoing nosocomial and community transmission.  相似文献   
996.
997.
Doppler ultrasonography represents a noninvasive method of examination of the peripheral vessels which has been known for a long time. The application of the technique in splanchnic vascularization provides information regarding the vessels permeability, collateral circulation (in case of total obstruction), hemodynamic alterations in normal and pathological conditions. Though the results reported in literature regarding the method are contradictory, the use of Doppler ultrasound for the assessment of splanchnic circulation is encouraging and the technique may represent a method of patient selection for invasive examinations.  相似文献   
998.
The identification of the etiological factor of many cervical precancerous lesions and cervical cancer, the human papillomavirus (HPV) is widely used. In this study, we evaluated the consensus and type-specific (TS) polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), line probe assay (LiPA, Innogenetics) and sequencing to determine the HPV types in cervical specimens. Out of 690 High-grade Squamous Intraepithelial Lesion (HSIL) samples, 86.7% were HPV positive and 13.3% HPV negative by consensus primers (MY09/MY11, L1C1/L1C2-1/L1C2-2 and/or GP5/6) directed PCR. Out of 598 HPV positive samples, 85.3% were typed by TS-PCR being HPV 6/11, 16, 18, 31 and/or 33, while 14.7% remained untyped. The most prevalent HPV type in the study group was HPV 16, identified in 35.5% cases, while HPV 31 was the second most frequent HPV type with a prevalence of 10.5%. They were followed by HPV types 6/11, 33 and 18 with a prevalence of 7.4%, 6.2% and 4.9%, respectively. Multiple HPV infections with two or more HPV types (6/11, 16, 18, 31 and/or 33) were found in 9.4% cases. A subset of 88 samples was further typed by RFLP and LiPA to determine the rare HPV types in HSIL samples. The most frequent low abundant HPV types in single infections in decreasing order were HPV 53, 58, 66, 56 and 52, while HPV 51 was the most frequent low abundant HPV type found in multiple HPV infections. Multiple HPV infections were mostly found by LiPA in 27.3% cases versus 14.8% cases found by RFLP. The perfect agreement between RFLP and LiPA assay pair was observed only for HPV types 16, 18, 34 and 59 (kappa value of 1). For other HPV types, the inter-assay agreement ranged from very good to no agreement indicating that neither assay is perfect. Sequencing was performed for 33 samples in cases where both RFLP and LiPA were inconclusive. Sequencing was shown to be a very good method in case of single HPV infection but not applicable in case of multiple HPV infections. Both RFLP and LiPA are good assays for epidemiological studies, although RFLP being cumbersome and time-consuming is less applicable than LiPA. Careful consideration has to be made before the implementation of either HPV typing methods in clinical laboratories.  相似文献   
999.
Cutaneous gene therapy, although a promising approach for many dermatologic diseases, has not progressed to the stage of clinical trials, mainly due to the lack of an effective gene delivery system. The main objective of this study was to construct and evaluate gemini nanoparticles as a topical formulation for the interferon gamma (IFN-gamma) gene in an IFN-gamma-deficient mouse model. Nanoparticles based on the gemini surfactant 16-3-16 (NP16-DNA) and another cationic lipid cholesteryl 3beta-(-N-[dimethylamino-ethyl] carbamate) [Dc-chol] (NPDc-DNA) were prepared and characterized. Zetasizer measurement indicated a bimodal distribution of 146 and 468 nm average particle sizes for the NP16-DNA (zeta-potential +51 mV) nanoparticles and monomodal distribution of 625 nm (zeta-potential +44 mV) for the NPDc-DNA. Circular dichroism studies showed that the gemini surfactant compacted the plasmid more efficiently compared to the Dc-chol. Small-angle X-ray scattering measurements revealed structural polymorphism in the NP16-DNA nanoparticles, with lamellar and Fd3m cubic phases present, while for the NPDc-DNA two lamellar phases could be distinguished. In vivo, both topically applied nanoparticles induced higher gene expression compared to untreated control and naked DNA (means of 0.480 and 0.398 ng/cm(2) vs 0.067 and 0.167 ng/cm(2)). However, treatment with NPDc-DNA caused skin irritation, and skin damage, whereas NP16-DNA showed no skin toxicity. In this study, we demonstrated that topical cutaneous gene delivery using gemini surfactant-based nanoparticles in IFN-gamma-deficient mice was safe and may provide increased gene expression in the skin due to structural complexity of NP16 nanoparticles (lamellar-cubic phases).  相似文献   
1000.
The aim was to determine the influence of atenolol on lidocaine pharmacokinetics in rats for one hour interval of time (average of a dental intervention). The study was carried out on 2 groups of Wistar rats treated with saline solution (0.5 ml/kg), respectively with atenolol (1.5 mg/kg), administered orally 24 hours and 3 hours before intraperitoneal administration of lidocaine (1.5 mg/kg). Blood samples were collected before and 5, 10, 20, 30, 60 minutes after lidocaine administration. Lidocaine plasma concentrations were determined by HPLC. Some pharmacokinetic parameters of lidocaine were statistically significant higher (p < 0.05, ANOVA) for the rats treated with atenolol compared with control group: Cmax (196.97 +/- 2.15 ng/ml vs. 125.29 +/- 2.90 ng/ml), AUD (7734.07 +/- 129.06 ng/ ml x min vs. 4478.57 +/- 296.61 ng/ml x min), AUC1 after 5 minutes (314.23 +/- 6.59 ng/ml x min vs. 190.71 +/- 19.75 ng/ml x min). Tmax was 20 minutes, similar for both groups. CONCLUSION: local anesthesia with lidocaine might be enhanced in the presence of atenolol compared to controls.  相似文献   
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