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981.
OBJECTIVE: To determine immunogenicity and optimum timing for administering the 23-valent pneumococcal vaccine after spinal cord injury (SCI). DESIGN: Double-blind, randomized, placebo control study. SETTING: SCI unit in a tertiary care medical center and community. PARTICIPANTS: Eighty-seven persons with recent SCI. INTERVENTION: Participants were randomized to receive either placebo or pneumococcal vaccine at 16 to 18 days versus 4 to 6 months postinjury. MAIN OUTCOME MEASURES: Antibody concentrations were measured prior to intervention and 1, 2, and 12 months afterward to evaluate the immune response to five serotypes of Streptococcus pneumoniae. Effects of demographic and injury-related variables on immune response were also evaluated. RESULTS: Timing of vaccination did not influence mean antibody concentrations for any serotype (p > .05). Ninety-five percent of vaccinated persons had twofold or greater increases in antibody concentration for at least one serotype when measured 1 month after vaccination versus 35% of placebo groups (p < .01). After 12 months, 93% of vaccinated persons in both groups maintained antibody concentrations twofold or greater than baseline values. CONCLUSIONS: Most participants developed an immune response to at least one serotype that was maintained for at least 12 months. Immune response varied according to serotype. Given the favorable immune response and no effect of timing, persons with SCI should receive pneumococcal vaccine during initial hospitalization.  相似文献   
982.
983.
In Drosophila melanogaster, the Polycomb-group (PcG) and trithorax-group (trxG) genes have been identified as repressors and activators, respectively, of gene expression. Both groups of genes are required for the stable transmission of gene expression patterns to progeny cells throughout development. Several lines of evidence suggest a functional interaction between the PcG and trxG proteins. For example, genetic evidence indicates that the enhancer of zeste [E(z)] gene can be considered both a PcG and a trxG gene. To better understand the molecular interactions in which the E(z) protein is involved, we performed a two-hybrid screen with Enx1/EZH2, a mammalian homolog of E(z), as the target. We report the identification of the human EED protein, which interacts with Enx1/EZH2. EED is the human homolog of eed, a murine PcG gene which has extensive homology with the Drosophila PcG gene extra sex combs (esc). Enx1/EZH2 and EED coimmunoprecipitate, indicating that they also interact in vivo. However, Enx1/EZH2 and EED do not coimmunoprecipitate with other human PcG proteins, such as HPC2 and BMI1. Furthermore, unlike HPC2 and BMI1, which colocalize in nuclear domains of U-2 OS osteosarcoma cells, Enx1/EZH2 and EED do not colocalize with HPC2 or BMI1. Our findings indicate that Enx1/EZH2 and EED are members of a class of PcG proteins that is distinct from previously described human PcG proteins.  相似文献   
984.
OBJECTIVE: To compare the intensity of postoperative pain after thoracotomy with 2 anesthetic techniques: 1) thoracic epidural block with bupivacaine administered before surgery (combined anesthesia with isoflurane) and 2) conventional balanced anesthesia with isoflurane and endovenous fentanyl. PATIENTS AND METHODS: Thirty patients scheduled for thoracotomy by lateral incision (T5-T6) were randomly divided into 2 groups of 15. Group A received 8 ml of 0.5% bupivacaine with adrenalin 1:200.000 30 min before start of surgery while group B received 8 ml saline solution through an epidural catheter inserted to T4-T8. Combined anesthesia (4 ml 0.5% bupivacaine through an epidural catheter 150 min after the first dose and isoflurane in 100% oxygen) was used in group A. Group B received balanced anesthesia with endovenous fentanyl 2.5 micrograms/kg and isoflurane in 100% oxygen. The difference in pain intensity during postoperative recovery was assessed by way of the following variables: number of boluses administered by epidural patient-controlled analgesia (bupivacaine 0.0625% and fentanyl 6 micrograms/ml); score on a visual analog scale of 10 at baseline and at 1, 3, 7, 11, 19 and 43 hours after surgery; and need for additional analgesia (diclofenac) during the 43 hours of study. Arterial gases were measured during the preoperative period and at 1, 3, 7, 19 and 43 hours after surgery. RESULTS: No significant differences in pain intensity measured on the visual analog scale, by the number of boluses per patients or by need for additional analgesia were found between the 2 groups. The total number of boluses administered and additional analgesic requirements were greater in the group receiving bupivacaine, although the difference was not significant (p = 0.095 and p = 0.056, respectively). Nor were there significant differences in pH and PaCO2 levels for the 2 groups. CONCLUSIONS: Analgesic efficacy after thoracotomy was similar for our 2 groups receiving either combined anesthesia (epidural bupivacaine at 0.5% and isoflurane) or balanced anesthesia with isoflurane and endovenous fentanyl.  相似文献   
985.
Twin-twin transfusion syndrome in monochorionic twin pregnancies is not understood completely and is controversial which hampers development of acceptable diagnostic and rational treatment strategies. A haemodynamic model was developed that relates fetal growth with (1) fetoplacental blood flow and fetomaternal effects, and (2) net twin-twin transfusion from donor to recipient twin. Fluid balance mechanisms were neglected. Placental vascular anastomoses (arteriovenous, venoarterial, arterioarterial, venovenous) were modelled as straight blood vessels connecting the placental cord insertions that grow during pregnancy. Poiseuille's law predicts significantly decreasing anastomosing resistances, and when placental sharing is unequal it is assumed that smaller placental fractions cause smaller blood volumes and pressures. Two coupled first-order differential equations describing each twin's blood volume were determined and analysis showed that placental and anastomotic development cause anastomotic blood flow to increase faster than fetal growth. Hence, it is proposed as the syndrome's underlying pathophysiology that fetal discordance increases progressively, beyond fetal compensatory capacity. Fewer anastomoses cause larger discordance, but its onset can vary widely during pregnancy. Arteriovenous plus compensating anastomoses produce dynamic steady-state growth patterns with large, opposite, measurable anastomotic blood flows. Clinical study of fetal growth patterns may identify the syndrome's underlying placental anatomy. Predicted trends depend only weakly on implemented fetal physiology and are most likely realistic. This knowledge could improve future management of the syndrome.  相似文献   
986.
Two hundred ten methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered between 1990 and 1997 from three Portuguese hospitals located in Lisbon and Oporto were analyzed by molecular fingerprinting techniques. The hybridization of ClaI restriction digests with the mecA- and Tn554-specific DNA probes combined with pulsed-field gel electrophoresis documented the abrupt appearance and extensive intrahospital spread of the Brazilian epidemic MRSA clone in the 1995 samples of each one of the three hospitals analyzed-suggesting the intercontinental transfer of this strain from Brazil to Portugal. The appearance of this clone may challenge the dominance of another highly epidemic imported clone-the Iberian MRSA, currently the most widely spread MRSA clone in Portuguese hospitals.  相似文献   
987.
PURPOSE: Vascular enumeration has been claimed to be an independent prognosticator for invasive breast cancer. Most of the studies have performed a manual count of the vessels. Few investigators have used image analyzers to reduce subjectivity in the measures. The aim of this retrospective study was to compare the manual vessel count to the counts obtained with an image analyzer and to estimate their possible prognostic influence. MATERIALS AND METHODS: We selected 112 patients with invasive ductal carcinoma, treated with radical mastectomy followed by chemotherapy and with a minimal follow-up time of 60 months (5 years). After immunostaining with factor VIII, we performed a double count of the vessels. First, we performed a manual count following Gasparini's criteria, and second, we used an image analyzer (Microm, Barcelona, Spain) to count the vessels in eight adjacent microscopic fields with a 20x objective, to reach a total area of 0.98 mm2. The image analyzer calculated the total number of vessels, their size and also the percentage of the field occupied by the vessels. RESULTS: In our series, vascular enumeration showed no significant association with histologic grade (Bloom-Scarff-Richardson grading), tumor size, or staging. CONCLUSION: Vascular enumeration with both methods was an independent prognosticator for relapse-free-survival (RFS) in both node-negative and -positive patients in the univariate analysis, but only vascular enumeration with the image analyzer was an independent prognostic factor in the multivariate analysis, together with lymph node metastases.  相似文献   
988.
989.
990.
The authors describe a 59-year-old woman who had a traumatic wound rupture 6 months following penetrating keratoplasty. While she was in the pre-operative holding area awaiting surgical repair, hemorrhagic choroidal detachments developed. Digital pressure was initiated on diagnosis of imminent expulsion of intraocular contents and maintained until repair of the wound rupture could be performed. Four months postoperatively, the patient's vision was 20/80 and her central pachymetry was 585 microns. This case demonstrates that a delayed-onset expulsive choroidal hemorrhage may be successfully managed with simple and rapid intervention based on knowledge of the disease process.  相似文献   
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