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Objective

This study assessed whether immediate postpartum insertion of levonorgestrel contraceptive implants is associated with a difference in infant growth from birth to 6 months, onset of lactogenesis, or breastfeeding continuation at 3 and 6 months postpartum compared to delayed insertion at 6 to 8 weeks postpartum.

Study design

We conducted a randomized trial of women in Uganda who desired contraceptive implants postpartum. We randomly assigned participants to receive either immediate (within 5 days of delivery) or delayed (6 to 8 weeks postpartum) insertion of a two-rod levonorgestrel contraceptive implant system. This is a prespecified secondary analysis evaluating breastfeeding outcomes. The primary outcome of this secondary analysis was change in infant weight; infants were weighed and measured at birth and 6 months. We used a validated questionnaire to assess onset of lactogenesis daily in person while participants were in the hospital, and then daily by phone after they left the hospital, until lactogenesis was documented. We used interviewer-administered questionnaires to assess breastfeeding continuation and concerns at 3 months and 6 months postpartum.

Results

Among the 96 women randomized to the immediate group and the 87 women to the delayed group, the mean change in infant weight from birth to 6 months was similar between groups: 4632?g in the immediate group and 4407?g in the delayed group (p=.26). Among the 97 women who had not experienced lactogenesis prior to randomization, the median time to onset of lactogenesis did not differ significantly between the immediate and delayed groups (65?h versus 63?h; p=.84). Similar proportions of women in the immediate and delayed groups reported exclusive breastfeeding at 3 months (74% versus 71%; p=.74) and 6 months (48% versus 52%; p=.58).

Conclusion

We found no association between the timing of postpartum initiation of levonorgestrel contraceptive implants and change in infant growth from birth to 6 months, onset of lactogenesis, or breastfeeding continuation at 3 or 6 months postpartum.

Implications

This study provides evidence that immediate postpartum initiation of contraception implants does not have a deleterious effect on infant growth or initiation or continuation of breastfeeding.  相似文献   
3.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
4.
目的探讨谷氨酸是否能够影响腺苷A2A受体对一氧化氮合酶(NOS)活力的调节。方法用1000ng/ml脂多糖(LPS)刺激小胶质细胞,分别加入100nmol/L A2A受体激动剂CGS21680以及不同浓度的谷氨酸(0,1,0,25,0,5mmol/L)干预,观察NOS活力变化。结果LPS诱导NOS活力增高,激活A2A受体可以产生抑制作用;0,25及0.5mmoL/L谷氨酸和A2A受体激动剂同时存在时,NOS活力进一步增高。结论高浓度谷氨酸可逆转腺苷A2A受体激动剂抑制升高NOS活力的作用。  相似文献   
5.
光化学作用对肿瘤细胞胞吞大分子的释放   总被引:1,自引:0,他引:1  
目的观察不同光敏剂在肿瘤细胞内的分布,以及光化学作用对肿瘤细胞胞吞大分子的释放作用.方法使用激光共聚焦显微镜观察ALA、ALA-HE、HMME、TPPSa2在肿瘤细胞SW480、K562的胞内分布,使用FITC-右旋糖酐观察肿瘤细胞对荧光标记大分子的胞吞作用,通过光照激发光敏化细胞,动态观察光化学作用前后胞吞大分子FITC-右旋糖酐的胞内分布变化.结果ALA、ALA-HE、HMME、TPPSa24种光敏剂均表现为胞质分布,核内分布少.ALA、ALA-HE的胞内分布主要表现为胞质内的弥散性荧光.HMME则表现为胞质内颗粒状荧光与弥散荧光同时存在.TPPSa2为典型的胞质内颗粒状荧光分布.光敏剂在SW480、K562两种肿瘤细胞的胞内分布没有明显差异.光照激发不同光敏剂对肿瘤细胞胞吞FITC-左旋糖酐的胞内分布影响不同.由TPPSa2及HMME活化而产生的光化学作用表现出明显的荧光颗粒重分布,ALA、ALA-HE则对胞吞荧光无明显重分布作用.结论不同光敏剂因其不同的理化性质而表现为不同的胞内分布.光化学作用可对肿瘤细胞胞吞大分子产生胞吞释放作用,其作用机制可能与光化学作用对胞吞泡的破坏有关.  相似文献   
6.
Pancreatic cancer is a lethal disease characterized by early metastasis, local invasion, and resistance to conventional therapies. To understand its etiology and eventually make prevention of it possible and effective, appropriate carcinogenesis models will certainly help us understand the effects of environmental and genetic elements on pancreatic carcinogenesis. The development of new treatment strategies to control cancer metastasis is of immediate urgency. Fulfillment of this task relies on our knowledge of the cellular and molecular biology of pancreatic cancer metastasis and the availability of biologically and clinically relevant model systems. Many of the existing pancreatic cancer carcinogenesis and metastasis animal models are described in this review. The advantages and disadvantages of each model and their clinical implications are discussed, and special attention is focused on experimental therapeutic strategies targeting pancreatic cancer metastasis.  相似文献   
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8.
上肢骨肿瘤切除后的自体骨移植重建   总被引:1,自引:0,他引:1  
目的探讨应用自体骨移植对上肢骨肿瘤切除后的骨缺损修复重建的效果。方法1998年8月~2004年3月,收治上肢骨肿瘤切除后的骨缺损16例。男8例,女8例。年龄7~45岁。经病理确诊,肱骨近端尤文肉瘤和骨肉瘤各1例;肱骨远端尤文肉瘤2例;桡骨远端骨巨细胞瘤8例,高分化软骨肉瘤2例,恶性纤维组织细胞瘤和骨肉瘤各1例。2例肱骨近端肿瘤行自体锁骨代肱骨;2例肱骨远端肿瘤行自体腓骨代肱骨;12例桡骨远端肿瘤中,1例行自体髂骨移植,11例行自体腓骨代桡骨进行重建。采用MSTS系统进行术后功能评价。结果2例肱骨近端自体锁骨移植患者分别随访36个月和12个月,术后保持部分肩关节前屈和后伸功能,但外展功能丧失;MSTS评分分别为23分和22分。2例肱骨远端自体腓骨移植患者分别随访4个月和6个月,肘关节功能良好,移植骨连接处已经出现骨愈合;MSTS功能评分分别为24分和19分。12例桡骨远端自体骨移植患者中11例随访6~75个月,功能良好,无明显并发症;1例髂骨植骨的桡骨远端骨巨细胞瘤术后3个月移植骨完全愈合,至今随访75个月,肿瘤无复发。MSTS功能评分18~27分,平均22.6分。结论自体骨移植在上肢骨肿瘤切除后骨缺损的重建,尤其是儿童的骨缺损重建中,是一种较好的方法。  相似文献   
9.
Abstract: Background: Fetal pulse oximetry improves the assessment of fetal well‐being during labor. The objective of this study was to evaluate women's satisfaction with their experience with this additional technology. Methods: We surveyed women participating in the FOREMOST trial, a randomized controlled trial comparing the addition of fetal pulse oximetry (FPO) to conventional cardiotocograph (CTG) monitoring (intervention group), versus CTG‐only (control group), in the presence of nonreassuring fetal status during labor. Our survey evaluated 3 aspects of women's experience: labor, fetal monitoring, and participation in the research. The survey was administered within a few days of giving birth and repeated 3 months later. Results: No differences were found between the intervention and control groups for women's evaluations of their labor, fetal monitoring, research, or overall experiences when surveyed on both occasions. Within each study group, a small but statistically significant decline occurred in women's scores for their experience of labor and overall experience from the initial survey close to the time of giving birth, to 3 months later. The magnitude of differences in responses over time was similar for the both groups. Women were more satisfied after a spontaneous or assisted vaginal birth than after cesarean section. Length of time the research midwife was present had a significant positive effect on women's ratings of their experience several days after giving birth (p = 0.006), but no effect at 3 months. Conclusions: The addition of fetal pulse oximetry for the assessment of fetal well‐being during labor did not affect childbearing women's perceptions of fetal monitoring or their labor. Women evaluated their experience in the research process positively overall. Small changes occurred in women's perception of their satisfaction over time. (BIRTH 33:2 June 2006)  相似文献   
10.
目的 观察改良睑黄色瘤切除术的应用效果。方法 选择病灶〈10mm以下的瘤体为手术观察对象,共22例(38眼)。按超皮损病灶边界1mm设计切口缘,梭形切除病灶,深达真皮层,在显微镜下清除皮下组织及切缘脂肪组织,松解切口边缘皮肤,连续皮内缝合切口。另外,酌情行上睑松弛矫治术。结果 失访2例(2眼),随访20例(36眼)6—12个月,未见黄色瘤复发,切口平整,痕迹隐约。结论 采用改良睑黄色瘤切除术更会增强眼睑形态美感。  相似文献   
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