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41.
BACKGROUND: The impersonation of parent and child by two other blood relatives is an important problem in parentage analysis involving potential immigrants. STUDY DESIGN AND METHODS: A statistic (AR) is proposed, based on the specific power of exclusion of paternity, which describes the ability of a child's test results to demonstrate evidence of nonparentage under the hypothesis that an ostensible parent is actually an older sibling. A case illustrates the value of A(R): a woman and her two alleged children were typed at 3 variable number of tandem repeat (VNTR) loci after 18 short tandem repeat (STR) loci initially showed strong evidence of the woman's maternity of one child and her exclusion from parentage of the second. AR and 1 - AR were calculated from the STR types of the first child. RESULTS: The woman was excluded from maternity of both children with the additional VNTR tests. Given the 18 STR test findings of the first child, the probability was 12 percent that there would be no inconsistencies with parentage in a sibling pretending to be a parent. CONCLUSION: The value 1 - AR, siblings not excluded from parentage, explains how a seemingly large number of examined loci can fail to reveal even one genetic inconsistency if two siblings have posed as parent and child. Approximately 25 STR loci appear necessary to achieve 95 percent confidence of detecting at least one genetic inconsistency indicative of nonparentage.  相似文献   
42.
大肠癌免疫组化表达与临床病理的关系   总被引:1,自引:0,他引:1  
目的:探讨大肠癌CEA、P53、nm23、Ki-67、MRP免疫组化表达特点和相互关系,及其与临床病理的关系.方法:回顾性分析2003-01/2006-07我院收治的73例大肠癌患者的临床病理及随访资料,并对其石蜡标本采用免疫组化SP染色法检测CEA、P53、nm23、Ki-67、MRP,分析其免疫组化特点及其与临床病理之间的关系.结果:CEA、P53、nm23、Ki-67、MRP在大肠癌中的阳性表达率依次为82.2%、68.5%、75.3%、84.9%和64.4%.CEA、MRP与大肠癌患者的各因素无统计学差异.P53、Ki-67和nm23与肿瘤的Dukes分期和淋巴结转移有关, P53、Ki-67在Dukes C、D期的阳性表达率(依次为82.8%和100%1明显高于Dukes A、B期者(59.1%和75.0%)(P<0.05),而nm23在Dukes C、D期的阳性表达率(58.6%)明显低于Dukes A、B期者(86.4%)(P<0.05).CEA与nm23的表达呈明显的负相关(r=-0.296,P=0.011),而P53和Ki-67表达之间呈现明显的正相关(r= 0.308,P=0.008),其他各指标间的表达无相关性.nm23、P53和Ki-67与预后因素关系明显,nm23在生存期≥3 a患者的阳性表达率(92.9%)高于生存期<3 a者(71.2%)(P<0.05),而P53和Ki-67在生存期≥3 a患者的阳性表达率(依次为42.9%和64.3%)明显低于生存期<3 a者(74.6%和89.8%)(P<0.05).结论:P53、Ki-67和nm23的表达与大肠癌的侵袭转移和预后密切相关.CEA可能是大肠癌的侵袭转移的促进因素.MRP所引起的耐药机制是一个相对独立的机制.CEA、P53、nm23、Ki-67可作为判断大肠癌恶性程度、侵袭转移以及预后的指标.  相似文献   
43.
INTRODUCTION: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy of atrial antitachycardia pacing (ATP) and the performance of pacing for AT prevention implemented into a new pacemaker. METHODS AND RESULTS: In patients with conventional indications for permanent pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary study objectives were to determine the safety of overall device functioning and its efficacy in terminating spontaneous AT. A secondary endpoint was to determine the reliability of AT detection. Pacemaker memory functions were used to analyze the impact of dedicated pacing algorithms on AT prevention. In 33 European and Canadian centers, 325 patients were enrolled (mean follow-up 2.3+/-1.3 months). Complication-free survival at 3 months was 88%. In 2,145 episodes stored with atrial electrograms, AT detection was confirmed in 97%. The algorithm for continuous overdrive pacing increased the percentage of atrial pacing to 97%. After ATP activation, 16,683 of 52,468 AT episodes were treated (120 patients). Of these, 8,903 episodes (53%) were terminated successfully by ATP. No proarrhythmic effect of preventive pacing or atrial ATP was observed. Preventive pacing algorithms increased the median percentage of atrial pacing from 62% to 97%. However, the number of AT/AF (atrial fibrillation) episodes (4.1 vs 4.1 per patient per day) and the time in AT/AF (13.7% vs 12.8%) was not significantly different before and after activation of preventive pacing. CONCLUSION: DDDRP pacing with a new system for AT therapy was safe and associated with successful pace-termination of AT in 53% of episodes. Preventive pacing and atrial ATP algorithms represent two new functions that can be implemented safely into pacemaker systems for nonpharmacologic treatment of ATs in patients requiring pacemaker therapy.  相似文献   
44.
Nifong TP  Light J  Wenk RE 《Transfusion》2002,42(12):1581-1584
BACKGROUND: Units of frozen S/D-treated plasma (SDP) must be transfused within 24 hours after thawing. To avoid waste, an attempt was made to determine how long SDP could be therapeutically effective after thawing and storing it at 20 degrees C. STUDY DESIGN AND METHODS: The microbiologic safety and the activity of labile coagulation factors were evaluated in units stored at 20 degrees C of thawed SDP units and FFP within 24 hours of collection (FFP24). Five SDP and FFP24 samples of each ABO blood group were cultured and assayed for coagulation factors daily over 5 days. Assays included FV, FVII, FVIIa, FVIII, F IX, FXI, protein S, antiplasmin, fibrinogen, prothrombin times (PTs), and activated partial thromboplastin times (aPTTs). RESULTS: None of the 80 bacterial cultures demonstrated growth under either aerobic or anaerobic conditions. FV, FVIII, F IX, FXI, fibrinogen, and the aPTT appeared to be stable in both thawed FFP24 and SDP. The PT increased slightly in thawed FFP24 and insignificantly in SDP. FVII decreased slightly in FFP24 but remained in the normal range, and FVIIa was low and constant. FVII was increased in SDP and FVIIa was markedly increased. Protein S decreased from initial normal values in FFP24 to very low values. Protein S was very low immediately after thawing in the SDP and continued to decline. Antiplasmin was normal and stable in thawed FFP24 but was low in SDP and remained constant after thawing. CONCLUSION: Sterile SDP that is stored at 20 degrees C provides sufficient coagulant activity of labile FV and FVIII to transfuse it for up to 5 days after thaw. Caution is warranted by decreases in Protein S and antiplasmin, clinical evidence of coagulopathy in some recipients of SDP, and a recent manufacturer's warning.  相似文献   
45.
Tendon echogenicity: ex vivo study   总被引:2,自引:0,他引:2  
Crass  JR; van de Vegte  GL; Harkavy  LA 《Radiology》1988,167(2):499-501
Recent publications discussing the echogenicity of normal tendon have described it variously as hyperechoic or hypoechoic. Since the echogenicity of tendon has been used to define normality and abnormality, certain knowledge of the normal echogenicity of tendon is crucial. Fresh tendon and muscle from beef hock was scanned with sector- and linear-array-transducer imaging at multiple angles and distances. The echogenicity of tendon was found to be very angle-dependent, a characteristic known as anisotropy. Scanned perpendicular to its long axis with a linear-array transducer, tendon was significantly more echogenic than muscle. With a change in angle, echogenicity of tendon decreased relative to that of muscle (the echogenicity of muscle remained the same), becoming isoechoic at angles of 2 degrees -7 degrees and hypoechoic at greater angles. Tendon studied with a sector transducer exhibited varying echogenicity. If echogenicity is used as a diagnostic criterion, the angle of the interrogating ultrasound beam must be very specifically defined.  相似文献   
46.
BACKGROUND: High doses (>or=500 mg/m) of cyclophosphamide are known to cause venoocclusive disease (VOD). The authors recently observed a patient treated with immunosuppressive cyclophosphamide doses (100 mg/day) and roxithromycin who developed VOD. Because roxithromycin inhibits cytochrome P450 (CYP) 3A4 and P-glycoprotein, the patient may have been exposed to higher cyclophosphamide and/or cyclophosphamide metabolite concentrations. METHODS: The effect of roxithromycin on the metabolism and toxicity of cyclophosphamide was studied using human hepatic microsomes and a human endothelial cell line. RESULTS: Cyclophosphamide or roxithromycin at concentrations from 0.05 to 500 micromol/L were not toxic to endothelial cells as assessed by lactate dehydrogenase (LDH) leakage assay. However, the combination of roxithromycin (500 micromol/L) and cyclophosphamide was toxic for all the tested cyclophosphamide concentrations (0.05 to 500 micromol/L) without clear concentration dependence (LDH ratio 38.3 +/- 11.0 [mean +/- SEM] for the combination with cyclophosphamide 0.05 micromol/L and 50.2 +/- 10.2 for the combination with cyclophosphamide 500 micromol/L; P 相似文献   
47.
Van Bel  F; Van Zwieten  PH; Guit  GL; Schipper  J 《Radiology》1990,174(1):165-169
To obtain information about intestinal hemodynamics of healthy neonates, the authors assessed velocity and volume of blood flow with duplex Doppler sonography in the superior mesenteric artery (SMA) in 91 stable preterm and term neonates. Blood flow velocity in the SMA and estimated volume blood flow increased linearly with gestational age and increasing body weight. The mean estimated volume blood flow (+/- standard deviation) was 43 mL/kg/min +/- 13 and did not depend on differences in body weight. The authors also assessed blood flow velocity in the SMA and volume blood flow in 18 infants with conditions that may affect blood supply to the bowel. Twelve infants who were small for gestational age appeared to have an abnormally low resistance of the vascular bed of the SMA during the 1st days of life, as compared with stable appropriate-for-gestational-age infants matched for gestational age. Three of six term neonates with cardiovascular abnormalities had left ventricular outflow obstruction and an abnormal blood flow velocity waveform of the SMA, suggesting a decrease in blood supply to the bowel. The results of this study may help in evaluations of intestinal perfusion in infants with abnormal conditions.  相似文献   
48.
Zusammenfassung Nachdem die laserinduzierte Stoßwellenlithotripsie von Gallengangssteinen technisch möglich ist, wurde in einer Tierversuchs reihe die percutane transhepatische Laserbehand lung von Gallenblasensteinen untersucht. In 8 Tierversuchen an weiblichen Schweinen konnte nachgewiesen werden, daß Punktion der Gallenblase, Dilatation des Arbeitskanals, (laserinduzierte) Steinzertrümmerung, Entfernung der Fragmente und des Instrumentariums in einer Sitzung möglich sind. Weder bei einfachem Hautverschluß, noch bei Fibrinklebung des Arbeitskanals wurden schwerwiegende Nebenwirkungen gesehen. Nach Laserlithotripsie finden sich Mucosadefekte und intramurale Hämatome, die sich innerhalb eines Monats komplett restituieren. Die Experimente zeigen, daß bei organerhaltender Gallenblasensteinlithotripsie die Ausbildung einer Fistel nicht abgewartet werden muß.
Percutaneous transhepatic laser lithotripsy of gallbladder stones
Summary Since laserinduced shock wave lithotripsy of gallstones is possible for treatment of common bile duct stones, the percutaneous transhepatic laserlithotripsy of stones in the gallbladder is examined in an animal study. In 8 animal experiments it could by shown that puncture of the gallbladder, dilatation of the working channel, (laserinduced) shock wave lithotripsy, removal of the fragments and the instruments are possible in one session. Neither when performing simple closure of the wound by suture nor by fibrinsealing severe side effects could be recognized. After laserlithotripsyablation of epithelium and hematomas can be ob served, which are restituted within one month. The experiments show that in organ-saving shockwave lithotripsy there is no need for waiting for the development of a fistula and the percutaneous approach can be simplified.
  相似文献   
49.
50.
FA Chiafari  ; RE Wenk 《Transfusion》1990,30(7):648-650
Single-locus DNA probes for tandem repeat sequences are now used in conjunction with particular endonucleases to characterize heritable restriction fragment lengths in parentage tests. Southern blots of this type, however, demonstrate only two attributes of an allele: its length and the presence of nucleotide sequences that are complementary to the probe. Not all restriction fragments of the same apparent length that react with the same probe are identical. Differences between comigrating fragments can be detected by the selection of a restriction enzyme that recognizes sites in a subset of the repeat sequences, and the information content of these loci is therefore increased. This report describes a paternity case in which two brothers appeared, after DNA phenotyping using Hinf I, to be the father. A second phenotyping using Hae III excluded one of the brothers.  相似文献   
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