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61.
The purpose of this study was to analyze the mortality and its prognostic factors in a Spanish cohort of very low birthweight (VLBW) infants during the period 2002 to 2005. Using the Spanish Society of Neonatology database (SEN 1500), 8942 infants with a birthweight < 1500 g were recruited. The overall mortality was 17.3%. However, this incidence underwent a significant decrease over the study period, from 19.4% in 2002 to 15.2% in 2005 ( P = 0.003). Mortality ranged from 12.4% in 25% of the participating neonatal units to 19.4% in a further 25%. Mortality was higher in outborn infants (25.8%) than in inborn infants (16.6%) ( P < 0.001). The mortality rates of these neonates are also presented by 100-g intervals (401 to 1500) and for the different hospitalization times: in the delivery room, within 24 hours and 28 days of birth, at 36 weeks of postmenstrual age, and on discharge. Of note was that mortality was greatest within 24 hours and 28 days of birth in each of the weight groups ( P < 0.001). In conclusion, in the cohort of infants < 1500 g examined, mortality in the period from 2002 to 2005 was still high, especially among newborns weighing < 1000 g. We did, however, observe a decreasing trend in mortality rates for the participating neonatal units over the 4 study years. Our findings highlight the need to promote intrauterine transport and improve neonatal transport as well as the management of these infants in the delivery room and within the first 28 days of life.  相似文献   
62.
Hysteroscopy today represents 200 years of salient innovations in instrumentation, new clinical applications for existing instruments, and continual modification of techniques, all aiming at observing, diagnosing, and treating pathologic conditions of the uterine cavity. Pioneers established the fundamental principles of intrauterine observation that steady technological advances would simplify and refine, all the way to the instrumentation and ancillary equipment now in use. Homage should be given and tribute paid to predecessors who made instrumentation, intrauterine distention, and illumination safe and practical for diagnostic and therapeutic hysteroscopy. Their accomplishments are remembered as we look with optimism to the many advances that undoubtedly will mark the future of hysteroscopy.  相似文献   
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Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity.  相似文献   
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La atención de pacientes con sospecha de un proceso infeccioso en los servicios de urgencias hospitalarios(SUH) se ha incrementado en la última década hasta suponer alrededor del 15-20% de todas las atenciones diarias. En la valoración inicial de estos enfermos se toman muestras para los distintos estudios microbiológicos en un 45% de los casos, donde predomina la obtención de hemocultivos (HC), en el 14,6% de todos ellos. La rentabilidad diagnóstica de estos HC es muy variable (2-20%). Los focos o procesos infecciosos más frecuentes sospechados o confirmados de las bacteriemias verdaderas(BV) en los SUH son la infección del tracto urinario (45%) y la infección respiratoria (25%). Por todo ello, la sospecha y confirmación de la BV tiene un relevante significado diagnóstico, pronóstico y obliga a cambiar algunas de las decisiones más importantes a tomar en el SUH. Entre otras, indicar el alta o ingreso, extraer HC y administrar el antimicrobiano adecuado y precoz. La intención de esta revisión es poner de manifiesto las evidencias científicas publicadas en los últimos cinco años, aclarar las controversias existentes actuales y comparar la capacidad para predecir bacteriemia de los últimos modelos predictivos publicados desde el año 2017 con los ya existentes en esa fecha, año en el que se publicó una revisión que dejaba abierta la propuesta de seguir buscando un modelo con un rendimiento adecuado para los SUH. Y así, a partir de ella, generar distintas recomendaciones que ayuden a definir el papel que pueden tener estos modelos o escalas en la mejora de la indicación de obtención de los HC, así como en la toma inmediata de otras decisiones diagnóstico-terapéuticas (administración precoz y adecuada del tratamiento antibiótico, solicitud de estudios complementarios y otras muestras microbiológicas, intensidad del soporte hemodinámico, necesidad de ingreso, etc.)  相似文献   
67.
BackgroundChronic obstructive pulmonary disease (COPD) is a complex and heterogeneous condition, in which taking into consideration clinical phenotypes and multimorbidity is relevant to disease management. Network analysis, a procedure designed to study complex systems, allows to represent connections between the distinct features found in COPD.MethodsNetwork analysis was applied to a cohort of patients with COPD in order to explore the degree of connectivity between different diseases, taking into account the presence of two phenotypic traits commonly used to categorize patients in clinical practice: chronic bronchitis (CB+/CB) and the history of previous severe exacerbations (Ex+/Ex). The strength of association between diseases was quantified using the correlation coefficient Phi (ɸ).ResultsA total of 1726 patients were included, and 91 possible links between 14 diseases were established. Although the four phenotypically defined groups presented a similar underlying comorbidity pattern, with special relevance for cardiovascular diseases and/or risk factors, classifying patients according to the presence or absence of CB implied differences between groups in network density (mean ɸ: 0.098 in the CB group and 0.050 in the CB+ group). In contrast, between‐group differences in network density were small and of questionable significance when classifying patients according to prior exacerbation history (mean ɸ: 0.082 among Ex subjects and 0.072 in the Ex+ group). The degree of connectivity of any given disease with the rest of the network also varied depending on the selected phenotypic trait. The classification of patients according to the CB/CB+ groups revealed significant differences between groups in the degree of conectivity between comorbidities. On the other side, grouping the patients according to the Ex/Ex+ trait did not disclose differences in connectivity between network nodes (diseases).ConclusionsThe multimorbidity network of a patient with COPD differs according to the underlying clinical characteristics, suggesting that the connections linking comorbidities between them vary for different phenotypes and that the clinical heterogeneity of COPD could influence the expression of latent multimorbidity. Network analysis has the potential to delve into the interactions between COPD clinical traits and comorbidities and is a promising tool to investigate possible specific biological pathways that modulate multimorbidity patterns.  相似文献   
68.
Background: Emergency cesarean section (EMCS) and breastfeeding difficulties increase the risk of postpartum depressive (PPD) symptoms. Early initiation of breastfeeding (EIBF) may not only alleviate PPD symptoms but also facilitate subsequent breastfeeding success. EMCS is a risk factor for not practicing EIBF. Therefore, it is important to understand the relationship between EMCS, EIBF, and PPD symptoms. Methods: We conducted a prospective cohort study in three areas of China. At baseline, a total of 965 mothers completed electronic questionnaires within 72 h postpartum. Women were screened for PPD symptoms using the Edinburgh Postpartum Depression Scale (EPDS). Multivariate logistic regression was used to identify the determinants of PPD symptoms. Mediation analysis was used to determine if EIBF mediated the relationship between delivery mode or breastfeeding education source and PPD symptoms. Results: The prevalence of EIBF was 40.6%; 14% of 965 mothers experienced EMCS, and 20.4% had PPD symptoms. The risk factors for developing PPD symptoms were excessive gestational weight gain (adjusted odds ratio [aOR] = 1.55, confidence interval [95% CI]: 1.03–2.33, p = 0.037) and EMCS (aOR = 2.05, 95% CI: 1.30–3.25, p = 0.002). The protective factors for developing PPD symptoms were monthly household income over CNY 10000 (aOR = 0.68, 95% CI: 0.47–0.97, p = 0.034), EIBF (aOR = 0.49, 95% CI: 0.34–0.72, p < 0.001), and prenatal breastfeeding education from nurses (aOR = 0.46, 95% CI: 0.29–0.73, p = 0.001). EIBF indirectly affected PPD symptoms in patients who had undergone EMCS (percentage mediated [PM] = 16.69, 95% CI: 7.85–25.25, p < 0.001). The source of breastfeeding education through EIBF also affected PPD symptoms (PM = 17.29, 95% CI: 3.80–30.78, p = 0.012). Conclusion: The association between EMCS on PPD symptoms was mediated by EIBF. By providing breastfeeding education, nurses could also help alleviate PPD symptoms.  相似文献   
69.
Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L−1. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.

This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™).  相似文献   
70.
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