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41.
目的:分析极低/超低出生体重儿败血症的临床特征、病原菌及药物敏感情况,为其早期诊断及治疗提供参考。方法:对2014年1月1日至2017年12月31日阜阳市人民医院新生儿重症监护病房(NICU)确诊的82例早产极低/超低出生体重儿败血症的临床表现、实验室检查、病原菌及药敏情况进行回顾性分析。结果:极低/超低出生体重儿败血症以早发型(≤7天)为主,晚发型以院内感染为主,临床表现缺乏特异性,实验室检查中白细胞、血小板出现减低,C反应蛋白和降钙素原增高。病原菌以革兰阴性菌为主,其次为革兰阳性菌和真菌。药敏结果显示革兰阴性菌对三代头孢、氨苄西林类抗生素100%耐药,对加他唑巴坦的抗生素耐药率较低,对碳氢酶烯类抗生素敏感。革兰阳性菌对β-内酰胺类、大环内酯类、氨基糖甙类及克林霉素等耐药率较高,对万古霉素、利奈唑烷敏感。82例败血症患儿中,死亡6例,死亡率为7.3%。结论:早产极低/超低出生体重儿败血症缺乏特异性临床表现,且发病率高,应密切观察患儿临床表现及动态监测其C反应蛋白、血小板等的变化,同时及时完善细菌培养及药敏试验,有效合理使用抗生素,以减少多重耐药菌株产生,改善患儿预后。  相似文献   
42.
According to sperm competition models, a male spawning in a disfavoured role should have spermatozoa with higher velocity but shorter longevity compared with a male spawning in a favoured role. Moreover, immunosuppressive androgens are needed to produce both secondary sexual characters and sperm cells. The 'sperm protection' hypothesis suggests that the immunosuppressive action of androgens has evolved to protect haploid spermatozoa, which are antigenic, from autoimmune attacks. Therefore, a male with high sexual ornamentation may be more susceptible to diseases but may possess better quality ejaculate than his less ornamented rival. We studied sexual ornamentation (breeding tubercles), ejaculation quality (sperm concentration, longevity and spermatozoal velocity) and intensity of parasitism in the cyprinid, Rutilus rutilus . Sperm longevity and spermatozoal velocity were positively correlated. Males having elaborated sexual ornamentation had longer-lived sperm and more Myxobolus mülleri parasites in the liver compared with males with low ornamentation. However, no difference was found between males with different degrees of ornamentation with respect to sperm concentration, spermatozoal velocity or other parasites. Since the highly ornamented males had higher sperm longevity, the present results are partly consistent with the predictions of the sperm competition models and the 'sperm protection' hypothesis.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 81 , 111–117.  相似文献   
43.
PurposeIn 2010, approximately 14.9 million babies (11.1%) were born preterm. Because preterm infants suffer from an immature thermoregulatory system they have difficulty maintaining their core body temperature at a constant level. Therefore, it is essential to maintain their temperature at, ideally, around 37 °C. For this, mathematical models can provide detailed insight into heat transfer processes and body-environment interactions for clinical applications.MethodsA new multi-node mathematical model of the thermoregulatory system of newborn infants is presented. It comprises seven compartments, one spherical and six cylindrical, which represent the head, thorax, abdomen, arms and legs, respectively. The model is customizable, i.e. it meets individual characteristics of the neonate (e.g. gestational age, postnatal age, weight and length) which play an important role in heat transfer mechanisms. The model was validated during thermal neutrality and in a transient thermal environment.ResultsDuring thermal neutrality the model accurately predicted skin and core temperatures. The difference in mean core temperature between measurements and simulations averaged 0.25±0.21 °C and that of skin temperature averaged 0.36±0.36 °C. During transient thermal conditions, our approach simulated the thermoregulatory dynamics/responses. Here, for all infants, the mean absolute error between core temperatures averaged 0.12±0.11 °C and that of skin temperatures hovered around 0.30 °C.ConclusionsThe mathematical model appears able to predict core and skin temperatures during thermal neutrality and in case of a transient thermal conditions.  相似文献   
44.
Background: Pregnancy-related risk factors for necrotizing fasciitis are poorly understood. We investigated pregnancy-related characteristics associated with the long-term risk of developing necrotizing fasciitis, a rare life-threatening infectious disease. Methods: We analyzed a longitudinal cohort of 1,344,996 parous women in Quebec, Canada between 1989 and 2020. The main exposure measures included complications of pregnancy such as gestational diabetes, preterm delivery, metabolic disorder, and other maternal characteristics. We followed the women over time to identify future hospitalizations for necrotizing fasciitis up to three decades after delivery. We estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association of pregnancy characteristics with risk of necrotizing fasciitis in time-varying Cox proportional hazards regression models. Results: A total of 420 women were hospitalized for necrotizing fasciitis during follow-up, including 83 (19.8%) with diabetes-related necrotizing fasciitis. The incidence of necrotizing fasciitis was elevated for women with gestational diabetes (2.9 per 100,000 person-years), preterm delivery (3.2 per 100,000 person-years), and metabolic disorders (5.4 per 100,000 person-years), compared with no pregnancy complication (1.1 per 100,000 person-years). Compared with no pregnancy complication, gestational diabetes was associated with 1.87 times the risk (95% CI 1.38-2.53), preterm delivery with 2.10 times the risk (95% CI 1.65-2.66), and metabolic disorder with 3.72 times the risk (95% CI 2.92-4.74) of developing necrotizing fasciitis over time. Pregnancy complications were more strongly associated with the risk of necrotizing fasciitis 5 years or more after delivery. Conclusions: Complications of pregnancy may be associated with the long-term risk of necrotizing fasciitis in women.  相似文献   
45.
The vertebrate ovary is an extremely dynamic organ in which excessive or defective follicles are rapidly and effectively eliminated early in ontogeny and thereafter continuously throughout reproductive life. More than 99% of follicles disappear, primarily due to apoptosis of granulosa cells, and only a minute fraction of the surviving follicles successfully complete the path to ovulation. The balance between signals for cell death and survival determines the destiny of the follicles. An abnormally high rate of cell death followed by atresia can negatively affect fertility and eventually lead irreversibly to premature ovarian failure. In this review we provide a short overview of the role of programmed cell death in prenatal differentiation of the primordial germ cells and in postnatal folliculogenesis. We also discuss the issue of neo-oogenesis. Next, we highlight molecules involved in regulation of granulosa cell apoptosis. We further discuss the potential use of scores for apoptosis in granulosa cells and characteristics of follicular fluid as prognostic markers for predicting the outcome of assisted reproduction. Potential therapeutic strategies for combating premature ovarian failure are also addressed.  相似文献   
46.
目的观察母乳联合鼠李糖乳杆菌预防早产儿喂养不耐受的临床疗效。方法选取2016年2月至2017年2月武汉大学人民医院收治的80例生后24h内入住本院儿科新生儿病房的早产儿,随机分配成2组,其中研究组40例,对照组40例。研究组以新鲜母乳联合鼠李糖乳杆菌早期开奶喂养,对照组以早产儿配方奶早期开奶喂养,比较2组早产儿喂养不耐受症的发生率及其恢复出生体重时间、达全胃肠道喂养时间、体重增长速度和住院时间的差异。结果研究组患儿喂养不耐受发生率低于对照组,研究组恢复出生体重时间、达全胃肠道喂养时间及住院时间均短于对照组(P0.05),研究组患儿体重增加速度快于对照组(P0.05)。结论早产儿早期喂养母乳联合鼠李糖乳杆菌能够较早建立全胃肠道营养,减少早产儿喂养不耐受症的发生率,促进患儿体重增长,缩短恢复出生体重时间及达全胃肠道喂养时间,降低住院天数。  相似文献   
47.
‘Giant sperm’, in terms of exceptionally long spermatozoa, occur in various taxa in the animal kingdom, particularly in arthropods. In freshwater ostracods (Cypridoidea) reproducing with giant sperm, males are equipped with a pair of specialized ejaculators, or Zenker organs, located in the distal part of vas deferens.  相似文献   
48.
Zhang L  Zhu C  Zhang X  Wan Y  Song J 《Steroids》2011,76(3):309-316

Objective

To investigate the mechanism for the dual effects of estrogen on vascular smooth muscle cells (VSMCs).

Methods

Cultured rat VSMCs were exposed to gradient concentrations (10−9-10−5 M) of 17β-estradiol (E2) with or without pre-administration of a broad-spectrum CYP450 inhibitor 1-aminobenzotriazole (ABT) (10 × 10−6 M) and an estrogen receptor (ER) antagonist ICI 182,780 (10−6 M), respectively. The growth, cell cycle progression, premature senescence, estrogen metabolites, reactive oxygen species (ROS) and DNA damage of the cells were analyzed with cell counting assay, flow cytometry, Western blot, liquid chromatography-mass spectrometry and comet assay, respectively.

Results

E2 in its physiological levels from 10−9 M to 10−8 M had a concentration-dependent promoting effect on growth of VSMCs. However, when the concentration increased over 10−8 M, the growth-promoting effect gradually reversed to a growth-inhibiting action. When the activity of CYP450s was blocked by ABT, the growth-promoting effect of E2 increased and did not reverse at high concentrations. Whereas when the ERs were blocked by ICI 182,780, E2 showed a pure growth-inhibiting effect. The E2 metabolites 2- and 4-hydroxyestradiols accumulated with the increase of E2 over 10−8 M, which accompanied by increased ROS, DNA damage and cellular senescence. All of these changes were eliminated by block of CYP450s, indicating that the VSMC growth inhibition by E2 is due to an increased production of ROS from accumulated E2 metabolites which induces DNA damage, leading to VSMC premature senescence.

Conclusion

The complex effect of E2 is due to two opposite actions: one ER-mediated and proliferative, and the other estrogen metabolite-induced and pro-senescent.  相似文献   
49.
目的:探讨单纯治疗慢性前列腺炎对其合并早泄的影响。方法:选择372例前列腺炎继发早泄的患者进行单纯针对前列腺炎的治疗,评价前列腺炎的治疗效果(包括前列腺炎症状评分(NIH-CPSI)、前列腺液常规等)及早泄的治疗效果(包括患者性生活满意度评分、配偶性生活满意度评分及阴道内射精潜伏期等)。结果:慢性前列腺炎经综合治疗后,患者的NIH-CPSI评分及前列腺液白细胞计数均显著降低(P0.05)。前列腺炎治愈或好转后,大多数患者的早泄情况得到明显改善,患者性生活满意度、配偶性生活满意度均较治疗前显著提高,阴道内射精潜伏期亦较治疗前明显延长,差异均具有统计学意义(P0.05)。结论:单纯治疗慢性前列腺炎继可使大部分患者并发的早泄明显改善,而对少数前列腺炎好转后早泄症状改善不明显者,可联合应用SSRIs等药物治疗。  相似文献   
50.
目的:探讨在经皮胆红素监测下早期蓝光干预对早产儿高胆红素血症的防治作用。方法:选择2009年10月-2011年10月我院新生儿科收治的86例出生体重≤2000 g,无出生窒息史的早产儿,按住院号单双号分为观察组46例和对照组40例。对照组按照我国2000年制定的新生儿黄疸干预推荐方案的干预标准进行光疗。观察组于出现黄疸和/或经皮胆红素85.50μmol/L,但尚未达方案的干预标准就进行光疗,监测经皮胆红素至黄疸消失。经皮胆红素值达187.5μmol/L以上时同时查静脉血监测血清总胆红素。比较2组早产儿经皮胆红素峰值及恢复正常时间。结果:观察组与对照组比较经皮胆红素峰值较低,黄疸持续时间较短,两组比较P均0.05,有统计学差异。结论:早产儿在经皮胆红素监测下进行早期蓝光干预有利于降低早产儿胆红素峰值,缩短黄疸持续时间,有效预防早产儿胆红素脑病。  相似文献   
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