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A quantitative competitive PCR (QC-PCR) assay for Epstein-Barr virus (EBV) has been developed to provide accurate measurement of EBV genome load in pediatric transplant recipients at risk for developing posttransplant lymphoproliferative disorder (PTLD). The assay quantifies between 8 and 5,000 copies of the EBV genome in 10(5) lymphocytes after a 30-cycle amplification reaction. For 14 pediatric patients diagnosed with PTLD, the median EBV genome load was 4,000, and 13 of the 14 patients had values of >500 copies per 10(5) lymphocytes. Only 3 of 12 control transplant recipients not diagnosed with PTLD had detectable viral genome loads (median value, 40). This median was calculated by using the highest value obtained by PCR testing on each of these patients posttransplantation. PCR values of >500 copies per 10(5) lymphocytes appear to correlate with a diagnosis of PTLD. By a modified protocol, the EBV genome copy number in latently infected adults was estimated to be <0.1 copy per 10(5) lymphocytes.  相似文献   
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A new type of cryptochrome, CRY-DASH, has been recently identified. The CRY-DASH proteins constitute the fifth subfamily of the photolyase/cryptochrome family. CRY-DASHs have been identified from Synechocystis sp. PCC 6803, Vibrio cholerae, and Arabidopsis thaliana. The Synechocystis CRY-DASH was the first cryptochrome identified from bacteria, and its biochemical features and tertiary structure have been extensively investigated. To determine how broadly the subfamily is distributed within living organisms, we searched for new CRY-DASH candidates within several databases. We found five sequences as new CRY-DASH candidates, which are derived from four marine bacteria and Neurospora crassa. We also found many CRY-DASH candidates from the EST databases, which included sequences from fish and amphibians. We cloned and sequenced the cDNAs of the zebrafish and Xenopus laevis candidates, based on the EST sequences. The proteins encoded by the two genes were purified and characterized. Both proteins contained folate and flavin cofactors, and have a weak DNA photolyase activity. A phylogenetic analysis revealed that the seven candidates actually belong to the new type of cryptochrome subfamily. This is the first report of the CRY-DASH members from vertebrates and fungi.  相似文献   
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Pain during sexual activity and ejaculation are the unspoken long-term complications of groin hernia repair. Laparoscopic surgical techniques are associated with decreased post-operative pain and earlier return to daily activities, but its effect on these complications is unclear. This study aims to investigate the effect of transabdominal preperitoneal repair (TAPP) on de-novo pain during sexual intercourse and ejaculation and to compare with open repair. For this reason, two groups were determined according to the surgical technique: the Lichtenstein repair and the TAPP groups and a questionnaire was sent to the patients a minimum of 6 months following the surgery. A total of 317 patients included, as 115 in TAPP and 202 in Lichtenstein repair group. No significant difference was observed concerning pre-operative pain during sexual activity and ejaculation in both groups (p = .75, p = .56). Following the surgery, the number of patients experiencing painful sexual activity was significantly higher in the Lichtenstein repair group compared to the TAPP group (19.3% vs. 11.3%, respectively, p = .03). The post-operative painful ejaculation rate was also significantly lower for the TAPP group (p = .04). The lower rates of post-operative dysejaculation and pain during sexual activity can be achieved with the advantage of laparoscopic surgery.  相似文献   
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1.  Naja flava venom heated to 100° C for 15 minutes interferes with intracerebrally inducedBrunhilde andLansing poliomyelitis infection in rhesus monkeys when the blockading agent is administered subcutaneously 24 hours after infection.
2.  It is suggested that this interference mechanism is based on the direct action of the heated venom on motoneurons, as evidenced by histopathologic changes in the spinal cords of normal rhesus monkeys injected subcutaneously with the venom.
3.  Similar histopathologic changes are seen when large doses ofNaja flava toxoid are injected subcutaneously into normal rhesus monkeys.
4.  An attempt has been made to extend the interpretation of the neurotoxoid and neurotoxin interference mechanism in poliomyelitis by correlating enzymatic studies of other workers with cobra venom and with chromatolytic cells refractory to poliomyelitis infection.
1.  Wird dasNaja-flava-Gift durch 15 Minuten auf 100° C erhitzt, dann hemmt es die intracerebral eingebrachteBrunhilde- undLansing-Poliomyelitis-Infektion bei Rhesusaffen, wenn das blockierende Agens 24 Stunden nach der Infektion subkutan zugeführt wird.
2.  Es wird angenommen, daß dieser Hemmungsmechanismus auf der direkten Einwirkung des erhitzten Giftes auf die Motoneurone beruht, was durch histopathologische Veränderungen im Rückenmark normaler Rhesusaffen, denen das Gift subkutan injiziert wurde, bewiesen wird.
3.  Ähnliche histopathologische Veränderungen werden bemerkt, wenn starke Dosen desNaja-flava-Toxoids normalen Rhesusaffen subkutan injiziert werden.
4.  Es wurde der Versuch gemacht, die Erklärung des Neurotoxoid- und Neurotoxin-Hemmungsmechanismus bei der Poliomyelitis durch die Vergleichung enzymatischer Studien anderer Forscher am Kobra-Gift und an chromatolytischen Zellen, die der Poliomyelitis-Infektion Widerstand leisten, zu erweitern.

With 7 Figures.  相似文献   
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BACKGROUND: Direct insertion of the trocar is an alternative method to Veress needle insertion for the creation of pneumoperitoneum. The safety of direct disposable shielded trocar insertion for the creation of pneumoperitoneum was assessed by comparing with Veress needle insertion during laparoscopic cholecystectomy (LC). METHODS: One thousand five hundred patients undergoing LC with pneumoperitoneum were included in this study. In 470 patients the Veress needle insertion technique was used, and in 1,030 patients direct trocar insertion technique was used. Patients having indications for open trocar insertion were excluded from the study. RESULTS: Complication rate was significantly higher in the Veress needle group (14% versus 0.9%; P <0.01), and the two major complications, gastric perforation and iliac artery laceration, were also encountered in this group. CONCLUSIONS: Our results suggest that with a lower complication rate, direct insertion of the disposable trocar is a safe alternative to Veress needle insertion technique for the creation of pneumoperitoneum. Such an approach has further advantages such as less cost/instrumentation and rapid creation of pneumoperitoneum.  相似文献   
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