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71.
72.
Hepatic tissue recovery in albino rat, after 3 weeks simultaneous administration of carbon tetrachloride (1 mL/kg b.wt) with different doses of Chelidonium majus was studied. Fibrotic change was prevented with both doses, while near normal tissue condition with microsteatosis and few necrotic cells was noted with the high dose.  相似文献   
73.
Objective. To investigate leukocyte lipocortin-1 production in rheumatoid arthritis (RA). Methods. Eight control and 8 RA subjects received 100 mg hydrocortisone intravenously. Leukocyte lipocortin-1 was measured by enzyme-linked immunosorbent assay. Results. Hydrocortisone induced significant increases in lipocortin-1 production by control mononuclear cells (MNC) (P = 0.006 versus baseline) but not by RA MNC (P = 0.44 versus baseline). Peak lipocortin-1 levels in control MNC were significantly higher than those in RA MNC (P = 0.014). Conclusion. These results indicate that glucocorticoid-induced MNC lipocortin-1 production is impaired in RA.  相似文献   
74.
In this article, Molecular Dynamics (MD) simulation is used to investigate the tensile mechanical properties of functional graded Ni–Al (Ni3Al) alloy with Ni coating. The grading profile, temperature, crystallographic direction, and concentration of vacancy defects have been varied and corresponding changes in the tensile properties are reported. In general, it has been revealed that functional grading may reduce the ultimate tensile strength (UTS) of this homogeneous alloy but increase Young''s modulus (YM). Furthermore, MD simulations suggest that elliptically graded Ni–Al alloy has the highest UTS at low temperature while at high temperature, the largest UTS is recorded for the parabolic grading. Besides, at any temperature, the parabolically graded Ni–Al alloy shows the largest YM, followed by linear grading and elliptical grading. Moreover, it is also observed that the [111] crystallographic direction for this alloy demonstrates the highest UTS and YM. At extremely low temperatures, lattice mismatch is also observed to exert a significant impact on the failure characteristics of functional graded Ni–Al alloys. This investigation also suggests that the vacancy defects introduced via removing either Al or Ni atoms degrades the UTS and YM of FGM alloys remarkably. Besides, it is also found that the UTS and YM of Ni–Al FGM alloys are very sensitive to Ni vacancies compared to Al vacancies. Parabolic grading demonstrates more resilience against vacancy defects, followed by linear and elliptical grading. This paper provides a comprehensive understanding of the mechanical properties of Ni–Al FGM alloys at the atomic level as a potential substitute for homogeneous alloys.

We revealed that the mechanical properties of Ni3Al (homogeneous alloy) could be modulated utilizing functional grading.  相似文献   
75.
76.
Three glutamic acid analogues, N-methyl-D-aspartic (NMDA), quisqualic (QQ), and kainic (KAI) acids were applied topically to the ventral surface of the medulla (VMS) in paralyzed, vagotomized and carotid sinus denervated cats hyperventilated to apnea. Respiratory and vasomotor effects were assessed by changes in phrenic nerve activity and systemic arterial blood pressure. All three agents to varying degrees raised systemic blood pressure, but only NMDA consistently initiated phrenic nerve activity at pCO2 levels below that observed in control trials. KAI and QQ raised blood pressure even in those animals in which they had little effect on initiating phrenic nerve activity. Furthermore, respiratory responses were obtained from localized areas on VMS, namely the intermedio-caudal zone (I-C areas); whereas blood pressure elevations could be obtained from wider VMS areas including the rostral zone (R areas). In addition, the effects of the three amino acids on blood pressure were quantitatively different with KAI causing much greater increases in blood pressure than QQ or NMDA. The respiratory and vasomotor effects of NMDA and QQ were blocked by the use of 2-amino-5-phosphonovaleric acid and L-glutamic acid diethylester, their respective antagonists. The results suggest that neurons in the VMS which cause respiratory and vasomotor responses are not identical. Cells containing receptors stimulated by NMDA predominantly increase respiration, whereas cells containing receptors excited by KAI are more effective in eliciting vasomotor responses.  相似文献   
77.
This retrospective single-arm study assessed real-world treatment patterns and clinical outcomes in patients with hormone receptor—positive/human epidermal growth factor receptor 2—negative (HR+/HER2−) advanced/metastatic breast cancer (A/MBC) who received palbociclib plus an aromatase inhibitor as first-line therapy in US community health systems. Using electronic health records from the Syapse Learning Health Network, 242 patients were identified as having received first-line palbociclib plus an aromatase inhibitor between 3 February 2015, and 31 July 2019 (data cutoff 1 February 2020) resulting in a minimum potential 6-month follow-up period. In total, 56.6% of patients had de novo A/MBC at initial breast cancer diagnosis, 50.8% had bone-only disease, and 32.2% had visceral disease. Median follow-up was 22.4 months. Disease progression (26.4%) and intolerance/toxicity (14.9%) were the main reasons for treatment discontinuation. The median (95% CI) real-world progression-free survival was 31.7 (27.9—not estimable (NE)) months and 2-year estimated overall survival (OS) rate was 78.0%. In total, 25.6% of patients died; however, OS data are limited by the small population size and insufficient follow-up time. These real-world effectiveness outcomes complement findings from other real-world studies and randomized controlled trials and support palbociclib plus an aromatase inhibitor as first-line therapy for HR+/HER2− A/MBC.  相似文献   
78.
PURPOSE: Population studies link increased BMI with an increased risk of cancer and cancer mortality and in particular a greater risk of RCC. We evaluated the impact of BMI and other clinical/pathological characteristics on survival in patients with RCC treated with radical or partial nephrectomy. MATERIALS AND METHODS: Between 1995 and 2003 patients undergoing radical (760) or partial (399) nephrectomy for RCC were entered into a database. BMI data were available on 1,137 of 1,159 (98%). Demographic and clinical/pathological parameters were analyzed. World Health Organization BMI definitions (normal-less than 25 kg/m(2), overweight-25 to 29.9 kg/m(2), obese-30 kg/m(2) or more) were used. RESULTS: A total of 75% of patients had greater than normal BMI with 472 (41.5%) overweight and 387 (34.0%) obese. Median followup was 33 months with a median overall survival of 110 months and a 5-year overall survival probability of 0.79. BMI categories were similar in age, gender, smoking status, presenting symptoms, tumor size, stage, and type of surgery. Significant increases in blood loss and operative time (p <0.05) were seen with increasing BMI. Although BMI 30 kg/m(2) or greater was associated with a higher proportion of clear cell histology (p = 0.002), it did not translate into an increased pathological stage, or incidence of metastasis. Multivariate analysis revealed age older than 65 years, systemic symptoms, surgery type, and pathological stage impacted overall survival (p <0.05). CONCLUSIONS: Although an increased BMI was associated with a greater proportion of clear cell histology, comorbidity, and surgical morbidity, BMI did not adversely impact overall or progression-free survival.  相似文献   
79.
BackgroundEndometriosis can lead to infertility. Since there is no definitive treatment for endometriosis, animal modelling seems necessary to examine the possible treatments. Mouse endometrium cannot be separated for endometriosis induction. In addition, transplantation of uterus into the abdominal viscera to induce endometriosis causes organ damage. In this study, we defined a new model of endometriosis leading to separability of endometrium and a safe anatomical region for transplantation.MethodsForty female mice were allocated to 5 groups: 1, sham; 2, allograft uterus transplantation of mice to anterior abdominal wall of mice; 3, allograft uterus transplantation of mice to mesentery of mice; 4, xenograft endometrial transplantation of rat to anterior abdominal wall of mice; 5, xenograft endometrial transplantation of rat to mesentery of mice. Adult female rats with a previous pregnancy experience were selected and placed in the vicinity of male rats for 2 weeks to induce estrogen secretion and increase endometrial thickness.ResultsIn the 4th group of animals, compared to sham, the peritoneal concentrations of VEGF‐A, TNF‐α, NO, MDA, and serum levels of CA‐125 and IL‐37 were increased and total body weight was decreased, while weight and size of endometrial lesions were increased significantly (P < .05). Genes expression of HOXA10 and HOXA11 were decreased significantly (P < .05) in groups 2 and 4 compared to sham.ConclusionsXenograft transplantation of endometrium from rat to anterior abdominal wall of mice can potentially mimic human endometriosis morphologically, histologically, and genetically.  相似文献   
80.
Background: The aerosol generated by an ultrasonic scaler contains microorganisms that can penetrate into the body through the respiratory system of dental surgeons and patients. The aim of this pilot study is to evaluate and compare the efficacy of commercially available preprocedural mouthrinses containing 0.2% chlorhexidine gluconate, an herbal mouthwash, and water in reducing the levels of viable bacteria in aerosols. Methods: This single‐center, double‐masked, placebo‐controlled, randomized, three‐group parallel design was conducted over a period of 45 days. Twenty‐four patients with chronic periodontitis were divided randomly into three groups (A, B, and C) of eight patients each to receive 0.2% chlorhexidine gluconate, herbal mouthwash, and water, respectively, as a preprocedural rinse. The aerosol produced by the ultrasonic unit was collected at patient's chest area, doctor's chest area, and assistant's chest area on blood agar plates in all three groups. The blood agar plates were incubated at 37°C for 48 hours, and the total number of colony‐forming units (CFUs) was counted and statistically analyzed. Results: The results showed that CFUs in groups A and B were significantly reduced compared with group C, P <0.001 (analysis of variance). Also, CFUs in group A were significantly reduced compared with group B, P <0.05 (independent t‐test). The numbers of CFUs were highest at the patient's chest area and lowest at the assistant's chest area. Conclusion: This study suggests that a routine preprocedural mouthrinse could eliminate the majority of bacterial aerosols generated by the use of an ultrasonic unit, and that 0.2% chlorhexidine gluconate is more effective than herbal mouthwash.  相似文献   
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