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151.
The evidence for abandoning the amniotic fluid index in favor of the single deepest pocket 总被引:3,自引:0,他引:3
Magann EF Chauhan SP Doherty DA Magann MI Morrison JC 《American journal of perinatology》2007,24(9):549-555
This study assessed whether the amniotic fluid index (AFI) or the single deepest pocket (SDP) is the best technique to estimate amniotic fluid volume. The AFI and SDP were compared to a dye-determined or directly measured amniotic fluid volume. A PUBMED search from 1990 to 2006 was conducted using the search terms "single deepest pocket" or "largest vertical pocket" or "maximum vertical pocket" or "2X1 pocket" AND "amniotic fluid index". One study compared the AFI and SDP to a dye-determined amniotic fluid volume. There were 1219 publications that used the search term SDP-LVP-MVP versus 4378 using AFI. Twenty publications contained both the AFI and SDP, but only six compared the AFI and SDP. Both the AFI and the SDP poorly identified abnormal amniotic fluid volumes, and neither technique was superior to the other. The AFI identifies a significantly greater number of women as having oligohydramnios versus the SDP but without any difference in perinatal outcomes. Compared with SDP, AFI excessively characterizes a greater number of pregnancies as having oligohydramnios leading to more interventions without improvement in perinatal outcome. The AFI should be abandoned and the SDP used to estimate amniotic fluid volume. 相似文献
152.
Barrilleaux PS Magann EF Chauhan SP York BM Philibert L Lewis DF 《The Journal of reproductive medicine》2007,52(4):293-298
OBJECTIVE: To evaluate the prognostic value of an amniotic fluid index (AFI) < or = 5 cm for an adverse perinatal outcome in pregnancies with the syndrome of hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). STUDY DESIGN: A prospective, observational study of patients with the HELLP syndrome. An ultrasound estimate of amniotic fluid volume was obtained on admission. Adverse intrapartum outcomes included amnioinfusion for variable decelerations and/or indicated abdominal/vaginal operative delivery for nonreassuring fetal heart rate changes. Maternal characteristics and perinatal outcome parameters were compared AFI < or = vs. > 5 cm. Statistical analysis was performed using chi2 analysis, Student's t test and receiver-operator characteristic curve (ROC) analysis. RESULTS: Between January 1996 and February 1999, 120 patients were enrolled. Twenty-six (22%) had an AFI < or = 5 cm. This group did not differ from that with AFI > 5 cm regarding the severity of the HELLP syndrome, admission-to-delivery interval (p = 0.354), variable decelerations in labor (p = 0.06), Apgar score of < 7 at 5 minutes (p = 0.361), cesarean delivery for nonreassuring fetal status (p = 1.0) or significant fetal acidosis (pH < 7.0 [p = 0.2101). ROC analysis revealed no AFI measurement between 0 and 16 cm that was useful for identifying the compromised fetus. CONCLUSION: Antepartum/intrapartum performance of AFI in patients with the HELLP syndrome is a poor prognostic test for subsequent fetal compromise. 相似文献
153.
154.
E K Dunn R J Macchia P S Chauhan G B Laungani N A Solomon 《Clinical nuclear medicine》1986,11(6):381-388
The efficacy and merit of testicular imaging, utilizing Tc-99m pertechnetate, were studied prospectively in a group of patients who presented with acute onset of scrotal pain. Consecutive admissions were studied. All were managed according to the likelihood of the problem being testicular torsion, which was determined from the clinical history, physical examination and the routine laboratory data. The final diagnostic outcome, whether by surgical exploration or clinical progress with conservative treatment, is collated with the preoperative scintigraphic interpretations, made with respect to predefined criteria. Analysis of the pretreatment images obtained in 57 patients shows that the radionuclide study is highly reliable in cases of testicular torsion and epididymo-orchitis. It appears to be much less dependable, however, in the other acute scrotal conditions. Torsions that are intermittent in nature or corrected manually apparently can have variable presentations. Certain difficulties and potential pitfalls encountered in interpreting the scintigraphic studies are discussed. 相似文献
155.
156.
Jagdeep S. Thakur C. G. S. Chauhan Vijay K. Diwana Dayal Chand Chauhan Anamika Thakur 《Indian Journal of Plastic Surgery》2008,41(2):190-194
Perineal burn contracture is a rare burn sequel. We conducted a retrospective analysis of cases with perineal burn contractures managed in a tertiary care centre of a Himalayan state. We found that all cases sustained burn injury from burning firewood and the time of presentation was two to six years after the burn injury. We analyzed our treatment method and have classified these contractures into two types. 相似文献
157.
D. R. Saban S. K. Chauhan X. Zhang J. El Annan Y. Jin R. Dana 《American journal of transplantation》2009,9(3):473-482
Certain components of a graft that provoke alloimmunity may not be vital for graft function or critical as targets of rejection. Corneal transplantation is an example of this, because graft epithelium plays a role in allosensitization, whereas corneal graft endothelium—which shares the same alloantigens—is the critical target in allorejection. In this study, we found that exploiting this biology by replacing donor epithelium of an allograft with an allodisparate third-party epithelium yields a marked enhancement in transplant survival. Such 'chimeric' allografts consisted of a C3H/He (H-2k ) corneal epithelium over a C57BL/6 (H-2b ) epithelial-denuded cornea (or v.v. ) and orthotopically placed on BALB/c (H-2d ) hosts. Conventional corneal allografts (C3H/He or C57BL/6) or isografts (BALB/c) were also transplanted on BALB/c hosts. Alloreactive T-cell frequencies (CD4+ interferon [IFN]-γ+ ) primed to the graft endothelium were strongly diminished in chimeric hosts relative to conventionally allografted hosts. This was corroborated by a decreased T-cell infiltration (p = 0.03) and a marked enhancement of allograft survival (p = 0.001). Our results represent the first successful demonstration of chimeric tissue, epithelial-denuded allograft plus third-party allodisparate epithelium, in the promotion of allograft survival. Moreover, chimeric grafting can be readily performed clinically, whereby corneal allograft rejection remains a significant problem particularly in inflamed graft beds. 相似文献
158.
Development of a System for Expressing Heterologous Genes in the Oral Spirochete Treponema denticola and Its Use in Expression of the Treponema pallidum flaA Gene 下载免费PDF全文
The present communication describes the construction of a new Escherichia coli-Treponema denticola shuttle vector based on the naturally occurring spirochete plasmid pTS1 and the expression of the heterologous T. pallidum flaA gene from the plasmid in T. denticola. This new shuttle vector system should prove useful in characterizing virulence factors from unculturable pathogenic spirochetes. 相似文献
159.
Treatment of pregnant mice with 3-methylcholanthrene (MC) causes lung and liver tumors in the offspring, the incidences of which are greatly influenced by the Ah locus regulated induction phenotype for aryl hydrocarbon hydroxylase activity (AHH) in both the mother and fetuses. In order to examine the biochemical and molecular mechanisms responsible for the modulating effect of maternal environment on tumor susceptibility, reciprocal crosses between responsive C57BL/6 and non-responsive DBA/2 mice were made and the pregnant mothers were treated i.p. on the 17th day of gestation with either olive oil alone, 30 mg/kg of MC, or 30 mg/kg of beta-naphthoflavone (beta NF). At various times after injection, the mothers were killed and the fetuses removed for enzymatic and molecular blot analysis. In fetal lung tissues, the absolute levels and relative induction ratios of AHH activity from D2B6F1 fetuses were very similar to those obtained in B6D2F1 fetuses during the first 24 h following a transplacental exposure to either inducing agent. This was also the case 48 h after an injection of beta NF. However, 48 h after exposure to MC, the AHH activity in fetal lungs from B6 mothers had declined to practically control values, whereas fetal lungs from D2 mothers still exhibited a high level of AHH activity. Similar induction kinetics for the CYPIA1 gene were obtained in fetal livers. These results were confirmed at the RNA level by quantitative slot-blot analysis of fetal RNA preparations. In both organs, treatment with inducing agents for the P450IA1 gene resulted in a rapid and early induction of CYPIA1 RNA by 4 h. Fetuses from D2 mothers, however, showed a more sustained induction of CYPIA1 RNA following exposure to MC than did fetuses from B6 mothers. These results suggest that the observed increase in tumor susceptibility observed in the offspring of D2 mothers compared to the offspring of B6 mothers was due, at least in part, to the differences in the persistence of induction of the CYPIA1 gene locus, and may be the result of differences in the clearance rates of MC from the fetal and maternal compartments or its pharmacokinetic distribution in the two types of maternal environments. 相似文献
160.
C K Chauhan S A Nanivadekar F R Billimoria 《Indian journal of physiology and pharmacology》1989,33(1):63-66
The present study was undertaken to determine whether, along with clinico-biochemical recovery there was associated restoration of hepatic drug metabolizing capacity in patients of cirrhosis after treatment of their cirrhosis, using serum antipyrine half life, the ideal index. Estimation of serum antipyrine half life before (26.34 +/- 2.4 hr) and after (18.83 +/- 2 hr) clinico-biochemical recovery showed significant (P less than 0.01) improvement in drug metabolizing capacity of liver. Biochemical parameters of liver function tests except serum total proteins and prothrombin time showed simultaneous improvement. 相似文献