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991.
OBJECTIVE: To investigate the expression of alphav integrin in developing human embryos. DESIGN: Observational study. SETTING: University medical center. PATIENT(S): Women undergoing IVF cycles. INTERVENTION(S): Immunofluorescent monoclonal antibodies against alphav integrin were used to stain human preimplantation embryos. MAIN OUTCOME MEASURE(S): Immunofluorescence microscopy and computerized image analysis were used to evaluate both qualitative and quantitative expression of integrins in human embryos. RESULT(S): The alphav integrin subunit was found to be expressed in human embryos throughout their development (from two-cell stage up to blastocyst). The expression of alphav integrin subunit gradually increased throughout embryo development as measured quantitatively by image analysis. CONCLUSION(S): The expression of alphav integrin subunit throughout the development of preimplantation human embryos reinforces the concept of a role for integrins in the process of implantation. 相似文献
992.
V Mirlesse A Cruz J Le Bidois P Diallo L Fermont F Kieffer J F Magny F Jacquemard R Levy M Voyer F Daffos 《American journal of perinatology》2001,18(7):363-371
Perinatal teams dealing with fetal heart disease frequently wonder which pregnancies might be terminated, and when delivery should take place in a specialized surrounding. We present a retrospective study of 229 fetuses, in which prenatal ultrasound showed a cardiac anomaly not compatible with a standard maternity ward delivery. One hundred nineteen pregnancies were terminated (group I) while 110 pregnancies led to the birth of a live baby (group II). Pathology in group I was discovered earlier than in group II (24 vs. 29.3 weeks' gestation; p <0.01), and associated malformations or chromosomal anomalies were much more frequent in group I (80/119 vs. 9/110; p <0.001). Among live born babies, three infants with transposition of the great arteries underwent Rashkind atrioseptostomy in the delivery room. With a minimum follow-up of 12 months, 69 children (63%) have undergone surgery. Among 92 survivors (1 child is lost to follow-up), 78 (71%) are asymptomatic and 14 symptomatic. Early prenatal diagnosis of fetal heart anomalies significantly facilitates prenatal work-up and perinatal care. We present the types of pathology having led to termination and define the situations in which children are at risk of perinatal hemodynamic compromise. 相似文献
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995.
Estradiol-17beta exerts profound neuroprotective actions following cerebral ischemia through multiple molecular mechanisms. To examine the putative anti-inflammatory mechanisms employed by estradiol during stroke, we explored the interactions between estradiol and inducible nitric oxide synthase (iNOS) in both wildtype and iNOS knockout (iNOSKO) female mice following permanent middle cerebral artery occlusion (MCAO). Female mice were ovariectomized and treated with estradiol. One week later, they were subjected to MCAO, and then killed 24 h later. Analysis of total, cortical and striatal infarct volumes confirmed that estradiol is neuroprotective in wildtype mice. Infarct volumes were also significantly smaller in female iNOSKO female mice, but estradiol did not further decrease injury. We found that one mechanism by which estradiol may act is by decreasing nitric oxide synthase 2 gene expression in the cortex and in the striatum of wildtype mice. These results show that the pro-inflammatory actions of iNOS exacerbate stroke-induced injury within the cortex and striatum, and that iNOS deletion is neuroprotective in ovariectomized and estrogen-replaced female mice. 相似文献
996.
A biosensor modified with peroxidase from crude extract of zucchini (Cucurbita pepo) was developed for the determination of dopamine in pharmaceutical samples. This enzyme catalyses the oxidation of dopamine to dopaminequinone, in presence of hydrogen peroxide, which the electrochemical reduction can be followed at a peak potential of -0.02 V. The recovery of dopamine from the samples ranged from 94.8% to 106% and a rectilinear analytical curve for dopamine concentration from 5.0 x 10(-4) to 3.0 x 10(-3) mol L-1 (r=0.9982) was obtained. The detection limit was 2.6x10(-5) mol L-1 and the relative standard deviation was less than 1.2% for 7.9 x 10(-4) mol L-1 dopamine in 0.1 mol L-1 phosphate buffer solution at pH 6.0 (n=10). 相似文献
997.
Eduardo Lazcano‐Ponce Attila T. Lőrincz Leticia Torres Jorge Salmerón Aurelio Cruz Rosalba Rojas Pilar Hernández Mauricio Hernández 《International journal of cancer. Journal international du cancer》2014,135(1):109-116
Since cervical cancer remains common in Mexico despite an established cytology screening program, the Ministry of Health recently introduced pilot front‐line HPV testing into the Mexican cervical cancer screening program (CCSP). Here, we present the key field performance metrics of this population‐based study. High‐risk HPV DNA (hrHPV) testing was conducted on self‐collected vaginal specimens from 100,242 women aged 25–75 years residing in Morelos State. All hrHPV positive women and a random sample of 3.2% (n = 2,864) of hrHPV negative participants were referred for colposcopic examination. The main disease endpoint of interest was cervical intraepithelial neoplasia grade 2 or higher (CIN2+). We calculated relative risk, positive predictive value and negative predictive value adjusted for screening test verification bias. The overall prevalence of hrHPV was 10.8% (95%CI 10.6–11.0). Women positive for hrHPV had a relative risk of 15.7 for histologically detectable CIN2+. The adjusted positive predictive value of the hrHPV test was 2.4% (95%CI 2.1–2.7); whereas the adjusted negative predictive value was 99.8% (95%CI 99.8–99.9). These findings suggest that large‐scale vaginal hrHPV testing in a middle‐income country can identify women at greater risk of advanced cervical abnormalities in a programmatically meaningful way but care is warranted to ensure that disease not detectable at colposcopy is kept to a minimum. PASS shows areas that need improvement and sets the stage for wider use of hrHPV screening of self‐collected vaginal specimens in Mexico. 相似文献
998.
Marco Antonio Botelho José Gomes Bezerra Filho Luciano Lima Correa Said Gon?alves da Cruz Fonseca Danusa Montenegro Ricardo Gapski Gerly Anne Castro Brito J?rg Heukelbach 《Journal of applied oral science : revista FOB》2007,15(3):175-180
Several different plant extracts have been evaluated with respect to their antimicrobial effects against oral pathogens and for reduction of gingivitis. Given that a large number of these substances have been associated with significant side effects that contraindicate their long-term use, new compounds need to be tested. The aim of this study was to assess the short-term safety and efficacy of a Lippia sidoides ("alecrim pimenta")-based essential oil mouthrinse on gingival inflammation and bacterial plaque. Fifty-five patients were enrolled into a pilot, double-blinded, randomized, parallel-armed study. Patients were randomly assigned to undergo a 7-day treatment regimen with either the L. sidoides-based mouthrinse or 0.12% chlorhexidine mouthrinse. The results demonstrated decreased plaque index, gingival index and gingival bleeding index scores at 7 days, as compared to baseline. There was no statistically significance difference (p>0.05) between test and control groups for any of the clinical parameters assessed throughout the study. Adverse events were mild and transient. The findings of this study demonstrated that the L. sidoides-based mouthrinse was safe and efficacious in reducing bacterial plaque and gingival inflammation. 相似文献
999.
Héctor Raúl Ibarra‐Sifuentes Ángel Del Cueto‐Aguilera Daniel Alberto Gallegos‐Arguijo Sergio Andres Castillo‐Torres Raymundo Vera‐Pineda Rolando Jacob Martínez‐Granados Alexandro Atilano‐Díaz Jesus Eduardo Cuellar‐Monterrubio Cesar Octaviano Pezina‐Cantú Edgar de Jesús Martínez‐Guevara Juan Francisco Ortiz‐Treviño Guillermo Rubén Delgado‐García José Guadalupe Martínez‐Jiménez Jesús Cruz‐Valdez Concepción Sánchez‐Martínez 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2017,21(5):459-464
Intradialytic hypotension is common complication in stage 5 chronic kidney disease patients on hemodialysis. Incidence ranges from 15 to 30%. These patients have levocarnitine deficiency. A randomized, placebo‐controlled quadruple‐blinded trial was designed to demonstrate the levocarnitine efficiency on intradialytic hypotension prevention. Patients were randomized into four groups, to receive levocarnitine or placebo. During the intervention period, levocarnitine and placebo was administered 0 and 30 min before each hemodialysis session, respectively. During the trial, 33 patients received 1188 hemodialysis sessions. We identified 239 (21.3%) intradialytic hypotension episodes. The intradialytic hypotension episodes were less frequent in the levocarnitine group (9.3%, 60 IH events) (P < 0.001). Hemodialysis is frequently perplexed by intradialytic hypotension episodes. Levocarnitine supplementation before each hemodialysis session efficiently diminishes the intradialytic hypotension episodes. This is a new application method that must be considered and explored. 相似文献
1000.
A case of epidermotropic cutaneous toxoplasmosis is reported. The patient, a 53-year-old man with chronic myelogenous leukemia in blast crisis, received a bone marrow allograft but continued to have severe pancytopenia. Numerous diffuse, palpable, purpuric nodules appeared 21 days after the transplant. Organisms were found within the epidermal keratinocytes--both singularly and in cysts. Dermal and neural infiltration was also present. Toxoplasma gondii was identified on the basis of the ultrastructural features of the parasite. Possible sources of infection include reactivation of a previous latent infection, transmission through a bone marrow allograft, or nosocomial acquisition. 相似文献