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排序方式: 共有7833条查询结果,搜索用时 0 毫秒
31.
32.
Gladys Morales Samuel Durán-Agüero Solange Parra-Soto Leslie Landaeta-Díaz Valeria Carpio Brian Cavagnari Israel Rios-Castillo Edna Nava-González Jhon Bejarano-Roncancio Beatriz Núñez-Martínez Karla Cordón-Arrivillaga Eliana Meza-Miranda Saby Mauricio-Alza Georgina Gómez Gabriela Murillo Jacqueline Araneda-Flores 《American journal of human biology》2023,35(8):e23900
33.
34.
Eduardo Bruera J Lynn Palmer Snezana Bosnjak Maria Antonieta Rico Jairo Moyano Catherine Sweeney Florian Strasser Jie Willey Mariela Bertolino Clarissa Mathias Odette Spruyt Michael J Fisch 《Journal of clinical oncology》2004,22(1):185-192
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain. 相似文献
35.
Gabriela F. Meresman Rosa I. Barañao A. Tenenbaum J. J. Singla N. R. Neuspiller Lia S. Rumi 《Archives of gynecology and obstetrics》1997,259(3):109-115
The aim of this study was to evaluate and compare the mitogenic effect of peritoneal fluid (PF) from women with mild and severe
endometriosis on the endometrial stromal cell proliferation. Increasing concentrations of PF from women with and without mild
or severe endometriosis were added to primary endometrial stromal cell cultures and3H-thymidine incorporation was used to assess DNA synthesis in these cultures. PF from women with mild endometriosis induced
a statistically significant dose-dependent increase in stromal cell thymidine uptake ranged from 5.8 to 14.5 fold, whereas
PF from women with severe endometriosis produced an average 51% inhibition of stromal cell proliferation of compared with
cells exposed to non-endometriosis PF or exposed to nutrient medium supplemented with 2.5% calf serum alone. PF samples from
patients with stage I endometriosis induced a statistically dose-dependent increase in stromal cell proliferation, whereas
PF from patients with stage IV endometriosis caused a significant inhibition. 相似文献
36.
Treatment variables in relation to oocyte maturation: Lessons from a clinical micromanipulation-assisted in vitro fertilization program 总被引:1,自引:0,他引:1
Ori M. Avrech Gil A. Goldman Onit Rufas Anat Stein Shoshana Amit Israel Yoles Haim Pinkas Benjamin Fisch 《Journal of assisted reproduction and genetics》1997,14(6):337-342
Objective: In an effort to understand the mechanism underlying the improved pregnancy rate observed in IVF cycles when gonadotropin-releasing
hormone analogues (GnRH-a) are applied, we investigated a possible relationship between treatment variables and oocyte-nuclear
maturity.
Design: Nuclear maturity was retrospectively assessed in cumulus-free, denuded oocytes, obtained from women undergoing micromanipulation-assisted
IVF treatment following controlled ovarian hyperstimulation with GnRH-a and menotropins.
Setting: The setting was the infertility and IVF unit of a tertiary academic medical center.
Participants: Two hundred twenty-one patients underwent 435 treatment cycles.
Main Outcome Measure: This was the proportion of germinal vesicle-intact immature (GVII) oocytes.
Results: One hundred fifty-four of the 3520 oocytes studied (4.4%) were in the GVII stage. These oocytes were found in 66 of the treatment
cycles (15.2%) and in 54 of the patients (24.4%). Cycles in which GVII oocytes were detected did not differ from those in
which all the aspirated oocytes were mature in the following respects: patient age, type and duration of infertility, controlled
ovarian hyperstimulation protocol and time of ovum pickup. However, the GVII group was characterized by a significantly higher
peak estradiol level, as well as a higher number of mature follicles visualized sonographically (diameter, >14 mm) and oocytes
retrieved.
Conclusions: Comparing the present findings with previously published data, it appears that the inclusion of GnRH-a in the stimulation
regimen is associated with a lower proportion of immature oocytes. A higher occurrence of oocyte-nuclear immaturity is apparently
associated with a significantly better ovarian response to stimulation. The high incidence of immature oocytes observed in
patients with normospermic partners and low fertilization rates in previous cycles may suggest that the fertilization failure
in some of these cases is due to oocyte, rather than sperm, dysfunction. 相似文献
37.
Gabriela de Freitas Laiber Pascoal Marina Vilar Geraldi Mrio Roberto Marstica Jr. Thomas Prates Ong 《Nutrients》2022,14(10)
Infertility is a growing public health problem. Consumption of antioxidant bioactive food compounds (BFCs) that include micronutrients and non-nutrients has been highlighted as a potential strategy to protect against oxidative and inflammatory damage in the male reproductive system induced by obesity, alcohol, and toxicants and, thus, improve spermatogenesis and the fertility parameters. Paternal consumption of such dietary compounds could not only benefit the fathers but their offspring as well. Studies in the new field of paternal origins of health and disease show that paternal malnutrition can alter sperm epigenome, and this can alter fetal development and program an increased risk of metabolic diseases and breast cancer in adulthood. BFCs, such as ascorbic acid, α-tocopherol, polyunsaturated fatty acids, trace elements, carnitines, N-acetylcysteine, and coenzyme Q10, have been shown to improve male gametogenesis, modulate epigenetics of germ cells, and the epigenetic signature of the offspring, restoring offspring metabolic health induced by stressors during early life. This indicates that, from a father’s perspective, preconception is a valuable window of opportunity to start potential nutritional interventions with these BFCs to maximize sperm epigenetic integrity and promote adequate fetal growth and development, thus preventing chronic disease in adulthood. 相似文献
38.
Gabriela Datsch Bennemann Emilia Addison Machado Moreira Leticia Cristina Radin Pereira Maiara Brusco de Freitas Diane de Oliveira Julia Carvalho Ventura Eduardo Benedetti Parisotto Yara Maria Franco Moreno Erasmo Benicio Santos Moraes Trindade Eliana Barbosa Norberto Ludwig Neto Danilo Wilhelm Filho 《The clinical respiratory journal》2022,16(6):475
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF. 相似文献
39.
Konrath EL Neves BM Lunardi PS Passos Cdos S Simões-Pires A Ortega MG Gonçalves CA Cabrera JL Moreira JC Henriques AT 《Journal of ethnopharmacology》2012,139(1):58-67
Ethnopharmacological relevance
The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.Materials and methods
The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.Results
AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.Conclusion
This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes. 相似文献40.