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Abstract: Background : Despite extensive literature on the topic, it is uncertain if grand (para ≥ 5) and great grand (para ≥ 10) multiparity are associated with adverse birth outcomes. We critically evaluate the evidence for and against the existence of adverse maternal and/or fetal outcomes in high parity women. Methods : An electronic search of MEDLINE and other bibliographic databases (Current Contents, EMBASE, and CAB) was conducted, and all relevant articles in English language were retrieved. Results : Findings on the association between high parity and maternal‐fetal birth outcomes are not consistent. Although the older literature tends to suggest that multiparity is a risk factor for negative birth outcomes, more recent reports are not supportive. Comparison across studies was further complicated by confounding factors like maternal age, socioeconomic status, and levels of prenatal care, as well as by variations in study designs and in the definition of parity itself. Furthermore, most studies that examined women of extreme parity (para ≥ 10) were handicapped by inadequate power. Conclusions : After accounting for quality, culture, and degrees of associations, the preponderance of evidence seems to point to possible existence of heightened risk for certain medical complications and placental pathologies among women of extreme parity. The literature also provides reasonable evidence for a higher‐than‐expected likelihood for occurrence of fetal macrosomia with advanced parity. 相似文献
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We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed. 相似文献
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Na+ dependence of in vitro pancreatic amylase release 总被引:1,自引:0,他引:1
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Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
The objective was to test the hypothesis that the optimal cryoprotective
agent for cryopreservation of human spermatozoa would be a solute for which
cells have the highest plasma membrane permeability, resulting in the least
amount of volume excursion during its addition and removal. To test this
hypothesis, theoretical simulations were performed using membrane
permeability coefficients to predict optimal procedures for the addition
and removal of a cryoprotectant. Simulations were performed using data from
four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide,
(iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations
were applied to determine approaches for the addition and removal of 1 M
and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to
maintain a cell volume within their osmotic tolerance limits. Based on
these data, ethylene glycol was predicted to be optimal for minimizing
volume excursions among the solutes evaluated. These predictions were then
experimentally tested using glycerol as the control cryoprotectant and
ethylene glycol as the experimental cryoprotectant. The results indicate
that there was a higher (P < 0.05) recovery of motile spermatozoa after
cryopreservation when using 1 M ethylene glycol than with 1 M glycerol,
supporting the hypothesis that use of the cryoprotectant for which the cell
has the highest permeability will result in higher cell survival.
相似文献
8.
Rapid detection and quantitation of hepatitis B virus DNA by real-time PCR using a new fluorescent (FRET) detection system. 总被引:6,自引:0,他引:6
Sani Hussein Aliyu Muktar Hassan Aliyu Hamisu M Salihu Surendra Parmar Hamid Jalal Martin David Curran 《Journal of clinical virology》2004,30(2):191-195
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work. 相似文献
9.
Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar. 下载免费PDF全文
A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation. 相似文献
10.
Healthcare for the elderly population presents enormous challenges, which are further complicated by ethnicity-related socioeconomic disparities in the United States. We set out to determine the predictors of hospital admissions in the elderly by conducting a retrospective cohort analysis of a nationally representative sample of community-dwelling individuals aged 70 and older in 1984 (n = 7541). Multivariate logistic regression analysis of data from the Longitudinal Study on Aging revealed that race, health status, type of family relationship, and activities of daily living (ADL) are significant predictors of hospitalization among the elderly. Older blacks are less likely to be admitted into the hospital, compared to their white counterparts (OR 0.68, 95%CI 0.52-0.89). Elderly persons who perceive their health status as being fair or poor are three times as likely to be hospitalized than those who perceived their health status as excellent (OR 2.99, 95%CI 2.15-4.15). Those with impairment in activities of daily living are twice as likely to be confined to the hospital than those without impairment (OR 1.78, 95%CI 1.64-1.96). Elderly persons living with nonrelatives are three times as likely to be admitted for short hospital stays than those living with spouses (OR 2.90, 95%CI 1.44-5.82). Future identification of predictors of hospital admissions in the elderly may help characterize those at risk and perhaps allow for focused and timely intervention. 相似文献