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2.
OBJECTIVE: To describe breastfeeding initiation among 210 urban African-American mothers with inadequate prenatal care. METHODS: This study is a case-control study of postpartum mothers recruited from four large urban hospitals. RESULTS: Mothers who chose to breastfeed were more educated, employed before birth, married, and using contraception postnatally. Regression model analysis controlling for demographic differences revealed that breastfeeding was significantly associated with a higher perception of severity of illness and higher confidence in the ability of health care to prevent illness. Breastfeeding mothers were less likely to reverse parent-child roles and had a lower perception of hassle from their infant's behavior. When comparing mothers who breastfed longer than 8 weeks to those who did not breastfeed, breastfeeding mothers had high scores related to empathy toward infants on the Adult-Adolescent Parenting Inventory as well as a low perception of hassle on the Parenting Daily Hassle. The perception of existing formal or informal social support did not influence breastfeeding behavior. CONCLUSION: Personal attributes of low-income urban mothers such as health beliefs and parental attitudes may play a role in the initiation and duration of breastfeeding. Low-income African-American mothers may be influenced in their choice to breastfeed by supportive messages from physicians and nurses delivering care to mothers and their newborns. Emphasis should be placed on the role breastfeeding can play in preventing childhood illnesses.  相似文献   
3.
Partial thickness burns (PTB) usually heal within 3 weeks. Prevention of infection and desiccation of the wounds are crucial for optimal healing. Early tangential excision of the burn eschar and allografting prevent deepening of the burns, and are therefore advocated for treatment with the best functional and aesthetic results. For superficial partial thickness burns (SPTB) conservative use of topical antimicrobial agents with frequent dressing changes are implemented. We compared the conservarive treatment for PTBs and SPTBs to grafting cryopreserved cadaveric allografts with no prior excision.

Twelve patients with flame PTB areas were allografted after mechanical debridement without excision of the burn wounds. The allografts were cadaveric skin cryopreserved by programmed freezing and stored at −180°C for 30–48 months. Matching burns for depth and area were treated with silver sulfadiazine (SSD) one to two times daily until healing or debridement and grafting were required.

It was found that 80 per cent of the cryopreserved allografts adhered well and 76 per cent of the treated areas healed within 21 days, whereas only 40 per cent of the SSD-treated burns healed within 21 days.

Partial thickness burns can be treated successfully with viable human allografts (cryopreserved cadaveric skin) with no prior surgical excision. The burn wounds heal well within 3 weeks. For deep partial thickness burns (DPTB) treatment with allografts has no advantage if they have not been previously excised.  相似文献   

4.
Microscopic colitis (MC) encompasses the two morphologically distinct entities of collagenous colitis (CC) and lymphocytic colitis (LC). MC was first described less than 30 years ago but is presently recognized as a relatively common cause of chronic diarrhea in the adult population. Remarkably, up to 10% of adults who have a colonoscopy for the investigation of chronic diarrhea, and have endoscopically normal appearing mucosa, may have MC. Patients with MC generally present with chronic diarrhea, which can be associated with cramping and bloating. Endoscopic and radiological examinations are usually normal. Histological assessment reveals inflammation consisting predominantly of lymphocytic infiltration, and a thickened subepithelial collagen band is diagnostic of CC. Both LC and CC can be associated with autoimmune diseases such as celiac disease, diabetes, arthritis and thyroiditis, yet the mechanisms involved in the pathogenesis remain unclear. Emerging studies suggest that a stepwise approach be taken in the medical management of MC. This approach includes antidiarrheal agents and stopping of any offending agents; budesonide or bismuth subsalicylate; and cholestyramine or 5-acetylsalicylic acid agents. In resistant cases, oral corticosteroids and other immune modulatory therapy have been used.  相似文献   
5.
PROBLEM: To determine if interleukin-16 (IL-16), IL-17, and IL-18 are present at the murine fetomaternal interface during pregnancy as a first step towards investigating their roles in fetomaternal relationship. METHODS: Expression of IL-16, IL-17, and IL-18, was assessed by immunohistochemistry (IHC) in the BALB/c x BALB/k (H2d x H2k), and the CBA/J x BALB/c non-abortion prone, and CBA/J x DBA/2 abortion prone matings. Enzyme-linked immunosorbent assay (ELISA) were performed for the two latter cytokines to compare local production in the abortion prone CBA/J x DBA/2 versus the non-abortion prone CBA/J x BALB/c matings. RESULTS: Expression of IL-17 was borderline. The anti-IL-16 staining specifically localized in the uterine stroma and glandular epithelium and was rather low in the placenta. IL-18 staining started in the peri-implantation uterus in the basal proliferative stroma, and was also traced, although weaker, in the glandular epithelium. In the immediate post-implantation period, a weak stromal staining persisted but there was a strong labeling of the ectoplacental cone. Interestingly, when the ectoplacental cone differentiates into placenta having a major histocompatibility complex (MHC) class I + spongiotrophoblast and a (MHC class I-) labyrinth, a very strong transient labeling of uterine natural killer (u-NK) cells was found. Later in gestation, IL-18 was also produced by giant cell and spongiotrophoblast. Finally, we compared by ELISA the production of IL-17/-18 in CBA/J x DBA/2 and CBA/J x BALB/c matings. We detected significantly more IL-18 in the non-abortion prone combination decidua or placenta. CONCLUSION: The three cytokines IL-16, IL-17, and IL-18 were detected at the fetomaternal interface with a tissue specific, stage-dependent distribution. The predominance of IL-18 secretion in the non-resorption prone matings lead us to question the general validity of the classical T-helper (Th)1/2 paradigm.  相似文献   
6.
PROBLEM: Abortion of chromosomally normal embryos in the CBA X DBA/2 mating combination is triggered by release of Th1 cytokines (tumor necrosis factor [TNF]-alpha, interferon [IFN]-gamma, and interleukin [IL]-1), which cause abortion via a novel prothrombinase, Fgl2, and polymorphonuclear leukocytes. The site of activation may be maternal vascular endothelium on arteries and veins nourishing the placenta. Activation of coagulation is also prominent in spontaneous abortion of chromosomally normal human embryos. We asked where is Fgl2 up-regulated in the uterus in murine abortions, and if similar Fgl2 expression occurs in human pregnancy failure. METHODS: Control CBA X DBA/2 pregnant mice, or from mice injected with TNF-alpha + IFN-gamma on day 7.5 of gestation, were removed on day 8.5, fixed, sectioned, and subject to in situ hybridization for Fgl2. Sections were also stained for fibrin. Elective first trimester termination samples or biopsies taken early in the course of a recurrent miscarriage were similarly fixed, sectioned, and analyzed by in situ hybridization. Control and cytokine-treated mice were anticoagulated with heparin, an activator of antithrombin III, and/or the direct anti-thrombin inhibitor hirudin. RESULTS: Low level Fgl2 expression localized to basal decidua remote from the embryo was noted in control mice; cytokine treatment, which causes greater than 80% of abortions, produced a striking up-regulation in this area as well as in a band at the junction of decidua and myometrium. Trophoblast also became strikingly positive. Fgl2 expression was associated with increased fibrin staining. Anticoagulation significantly protected against abortions, but doses were limited by the complication of retroplacental hemorrhage. In tissue from normal first trimester pregnancy, minimal Fgl2 positivity was seen in some villous syncytiotrophoblast, in villous stroma, cytotrophoblast, and in some cells in decidua. In spontaneous abortion of normal embryo, striking Fgl2 positivity was seen in syncytiotrophoblast and extravillous cytotrophoblast, in association with areas of thrombus formation. CONCLUSIONS: Fgl2 appears to be physiologically expressed and may protect against the internal danger of maternal and/or fetal bleeding during pregnancy and at parturition; a role in inhibiting transplacental traffic is also possible. External dangers in the form of stress, endotoxin, and antigens eliciting Th1 cytokine responses upregulate Fgl2 prothrombinase in trophoblast as well as in decidua, which results in spontaneous abortion of immunogenetically "weaker" embryos.  相似文献   
7.
The exposure of murine peritoneal cells to anti-H-2 sera results in a diminished expression of H-2 antigen on the cell surface. Concomitant with this "H-2 modulation" the capacity of macrophages to bind sheep red blood cells coated with antibody and complement (EAC) was markedly diminished. In contrast, there was no change in the capacity of modulated macrophages to bind sheep red blood cells coated with antibody alone (EA). Antibodies to K end H-2 specificities were more effective in reducing the binding of EAC than antibodies to D end H-2 specificities. Exposure of peritoneal cells to O or Ly antisera had no effect on the formation of EAC rosettes. Exposure of peritoneal cells to anti-H-2 sera, under conditions which would not allow modulation of H-2 antigens, also prevented the reduction of EAC binding. Thus, the EAC receptors and H-2 antigenic specificities seem to be closely related on the surface of peritoneal cells, but constitute distinct cell surface structures. Preliminary evidence indicates that vinblastine, a microtubule depolymerizing agent, may disrupt the close association of EAC receptors and H-2 antigens. It is suggested that the association of EAC receptors and K end H-2 determinants on the membrane of macrophages may have implications for the regulation of the immune response by H-2-linked Ir genes.  相似文献   
8.
ObjectivesQuantify how observable characteristics contribute to influenza vaccination disparities among White, Black, and Hispanic nursing home (NH) residents.DesignRetrospective cohort.Setting and ParticipantsShort- and long-stay U.S. NH residents aged ≥65 years.MethodsWe linked Minimum Data Set (MDS) and Medicare data to LTCFocUS and other facility data. We included residents with 6-month continuous enrollment in Medicare and an MDS assessment between October 1, 2013, and March 31, 2014. Residents were classified as short-stay (<100 days in NH) or long-stay (≥100 days in NH). We fit multivariable logistic regression models to assess the relationships between 27 resident and NH-level characteristics and receipt of influenza vaccination. Using nonlinear Oaxaca-Blinder decomposition, we decomposed the disparity in influenza vaccination between White versus Black and White versus Hispanic NH residents. Analyses were repeated separately for short- and long-stay residents.ResultsOur study included 630,373 short-stay and 1,029,593 long-stay residents. Proportions vaccinated against influenza included 67.2% of White, 55.1% of Black, and 54.5% of Hispanic individuals among short-stay residents and 84.2%, 76.7%, and 80.8%, respectively among long-stay residents. Across 4 comparisons, the crude disparity in influenza vaccination ranged from 3.4 to 12.7 percentage points. By equalizing 27 prespecified characteristics, these disparities could be reduced 37.7% to 59.2%. Living in a predominantly White facility and proxies for NH quality were important contributors across all analyses. Characteristics unmeasured in our data (eg, NH staff attitudes and beliefs) may have also contributed significantly to the disparity.Conclusions and ImplicationsThe racial/ethnic disparity in influenza vaccination was most dramatic among short-stay residents. Intervening on factors associated with NH quality would likely reduce these disparities; however, future qualitative research is essential to explore potential contributors that were unmeasured in our data and to understand the degree to which these factors contribute to the overall disparity in influenza vaccination.  相似文献   
9.
PROBLEM: In an attempt to predict successful embryo transfer and implantation, we measured interleukin (IL)-6 levels in culture supernatants of co-cultured preimplantation human embryos. We tested whether all in vitro fertilized human embryos in co-cultures do secrete IL-6, and whether there was any difference in such production between embryos that successfully reached the blastocyst stage and blocked embryos. We also addressed the question of IL-6 secretion by co-culture support cells, namely Vero cells themselves. METHOD OF STUDY: Each fertilized oocyte was cultured individually and transferred in culture wells supplemented with a feeder layer of Vero cells at day 2. In vitro IL-6 production was measured by bioassay of the culture media. RESULTS: Because Vero cells themselves secrete IL-6, it became impossible, in co-culture, to quantify production of IL-6 by the sole embryos. On the other hand, the co-culture technique has shown us that embryos are likely to consume IL-6. There was no difference between blastocysts and blocked embryos. CONCLUSIONS: IL-6 levels in human embryo co-cultures do not correlate with future successful embryo transfer.  相似文献   
10.
Background: Pars planta vitrectomy has evolved as an alternative method in the treatment of more complicated rhegmatogenous retinal detachments. We report a series of patients who underwent primary vitrectomy with gas tamponade without the use of additional scleral buckling. Methods: A retrospective study of 53 patients with a follow-up of 6–45 months (mean 17.8 months) was carried out. Preoperative findings included unusual, multiple or large breaks, vitreous haemorrhage, proliferative vitreoretinopathy and bullous retinal detachment. Preoperative visual acuity was between light perception and 1.0, with 30% (16/53) of patients with 0.4 or better. Results: Retinal reattachment was achieved in 64% of cases (34/53) with one and in 92% (49/53) with one or more operations. Final visual acuity was between light perception and 1.0, with 41% (22/53) of patients with 0.4 or better. Cataract formation occurred in 86% (37/43) of all patients with a clear lens preoperatively. Macular pucker was noted in 11 % (6/53) and postoperative proliferative vitreoretinopathy causing redetachment in 6% (3/53). Conclusion: With primary vitrectomy, a high final anatomical success rate with few intraoperative complications can be achieved in more complicated forms of rhegmatogenous retinal detachment. The major drawback of the procedure is the high incidence of post-operative cataract formation.  相似文献   
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