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41.
A screening program was implemented to identify hrB- donors. D- C+, D-C-, and D+C- samples from African-American donors were typed with multiple examples of anti-hrB and anti-hrB-like, and one example each of anti-V and anti-VS. Of 75 D-C+ donors, 4 (5%) typed as hrB-, and 14 others had weak or variable expression of hrB. Of these 18 individuals, 15 were V-VS+, and 3 were V+VS+. No hrB- sample was found in 90 C- donors, 26 of whom were V+VS+, and 1 was V-VS+. A review of our records of 44 hrB- patients and donors studied earlier revealed that at least 12, and possibly as many as 30, carried r or rs. All hrB- donors found in our screening program had D-C+VS+ RBCs, indicating an overrepresentation of r. Our record review also showed that the presence of r and rs more often results in hrB- RBCs, and that the most effective way to screen for hrB- donors is to type African Americans who have D-C+ RBCs.  相似文献   
42.
Anti-Yta is an antibody to a high-frequency (99.8%) antigen and has been reported to have variable clinical significance. A retrospective review of monocyte monolayer assay (MMA) results on sera from 79 patients with anti-Yta was conducted to determine the reliability of this assay to predict the clinical significance of anti-Yta. Results of the MMA, other serological tests, and patient transfusion histories were analyzed. The MMA was found to be a reliable predictor of the clinical significance of anti-Yta when samples for analysis were collected at least six weeks after initial detection of the antibody. Only 18.2 percent of those examples of anti-Yta tested appeared to be clinically significant.  相似文献   
43.
Restoration of bone stock in revision surgery of the femur   总被引:3,自引:0,他引:3  
Three hundred and four femoral revisions were performed from 1987 to the end of 1990. All were done with cementless titanium calcar replacement prostheses, designed for proximal bone loading. Type III bone deficiencies were present in 160 femurs, all requiring supplemental cortical bone plates for bony augmentation. All grafts united and provided increased bone stock in the long term. Physiologic loading is important for graft remodeling and maturation. Hip scores have improved from an average Harris Hip Score of 44 to 84. Current survivorship at 10 years is 96%, and the revision rate is 3.2%. Thigh pain is mild in 3% of cases. There have been no late failures or distal lysis noted to date.
Résumé  De 1987 à 1990, on a procédéà 304 reprises de prothèse totale de hanche (PTH) associées à des implants fémoraux standard en alliage de titane non cimentés et spécifiquement étudié et réalisés pour bien s’adapter à la morphologie osseuse et à la résistance mécanique proximale. 160 cas de fémur nécessitèrent – vu la présence de perte de sustance osseuse de type III – la mise en place sur la corticale de plaque osseuse de remplacement afin d’augmenter et la repousse fémorale osseuse. On observe dans les cas de reprise de PTH, une amélioraton du recul moyen: ce dernier passait de 44 mois (selon l’échelle de le Harris Hip score) à 84 mois. A l’heure actuelle, le taux actuariel de survie des implant est de 96% à 10 ans avec un taux de reprise de 3.2%. On note la presence de douleur à la cuisse dans 3% des cas, mais à l’heure actuelle, on ne rapporte aucun échec tardif ni osteolyse distale.


Accepted: 7 December 1999  相似文献   
44.
PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy.  相似文献   
45.
46.
Genetic polymorphism in HPC2/ELAC2 was recently associated with risk of sporadic prostate cancer. To determine the contribution of two HPC2/ELAC2 missense variants (Ser217Leu and Ala541Thr) to the risk of developing prostate cancer, we conducted a population-based case-control study of middle-aged men (40-64 years). Cases (n=591) were ascertained from the Seattle-Puget Sound Surveillance, Epidemiology, and End Results Cancer Registry and Controls (n=538) from the same general population were identified through random-digit dialing. Subjects were residents of King County, Washington, and were frequency matched on age. Cases (32%) had a slightly higher frequency of the Leu217 variant compared with controls (29%), but there were no differences in the frequency of the Thr541 allele (4%). When considering joint genotypes, white men homozygous for the Leu217 variant on an Ala541/Ala541 background had an increased risk of prostate cancer [odds ratio (OR)=1.84; 95% confidence interval (CI), 1.11-3.06]. Different risk profiles were also observed when cases were stratified by disease aggressiveness. Men with at least one Leu217 allele had an elevated risk (OR=1.34; 95% CI, 1.02-1.76) of less aggressive prostate cancer (localized stage and Gleason score < or = 7), with a stronger association among men with two Leu217 alleles (OR=1.73; 95% CI, 1.08-2.77). The Ala541Thr polymorphism was not associated with risk, and neither variant was associated with more aggressive prostate cancer phenotypes. We estimate that the Ser217Leu genotype may account for approximately 14% of less aggressive prostate cancer cases and 9% of all sporadic cases in the general United States population of white men 相似文献   
47.
An abbreviated version of the Nurse-Midwifery Clinical Data Set was used to gather data on all women (n = 3,049) who began intrapartum care with a nurse-midwife in three sites. Demographic information, intrapartum care, and outcomes were recorded. The association of ambulation in labor with operative delivery was examined in a low-risk sample (n = 1,678) of women who did not receive care measures (epidural anesthesia, oxytocin induction or augmentation) that preclude mobility in labor. Women who ambulated for a significant amount of time during labor (compared with those who did not ambulate) had half the rate of operative delivery (2.7% vs. 5.5%).  相似文献   
48.
Epidural analgesia is widely available and increasingly popular in the United States for pain relief in childbirth. Although it provides superior pain relief for most women, it is not without significant short- and long-term side effects. It is costly and requires the use of numerous other technologic interventions. Because women have information needs surrounding childbirth and value self-determination, full informed consent regarding epidural analgesia should be a priority in patient care. The best time and place in which to accomplish this is during the prenatal period.  相似文献   
49.
BACKGROUND: Several lines of evidence point to serotonergic abnormalities in patients with panic disorder (PD). Our goal was to further examine central serotonergic function in panic patients using autonomic and subjective responses to the postsynaptic serotonin 5-HT1D receptor agonist Sumatriptan. METHOD: Using a double-blind, randomized, placebo-controlled design, we assessed autonomic and subjective responses to oral Sumatriptan (100 mg) and placebo in 15 patients with PD, free of medication. Subjective responses were measured using the Hamilton Anxiety Rating Scale (HAM-A), National Institute of Mental Health Anxiety Scale (NIMHA), a modified version of the Panic Symptom Inventory (PI), Hamilton Depression Rating Scale (HAM-D), and Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: PD patients exhibited significantly enhanced autonomic and subjective responses following challenge with Sumatriptan. We observed an increased pulse rate and augmentation of various parameters measured on different anxiety scales. A constant inclination of aggravation of the measured parameters was detected during the hour post challenge. CONCLUSION: Oral administration of Sumatriptan, a 5-HT1D agonist, has been associated with an anxiogenic effect in PD patients.  相似文献   
50.
We evaluated somatic genetic alterations in the kinase domain of the EGFR gene in the tumors of 219 non-small cell lung cancer patients of primarily Caucasian and African American origins. We identified 26 patients (12%) whose tumors had a mutation in the EGFR gene, and 11 (5%) patients carried novel genomic variations consistent with germ-line polymorphisms. All but one mutation were identified in Caucasian patients affected with adenocarcinoma. EGFR mutations were more frequent in women and in nonsmokers, but a significant portion of the affected patients were men (12 of 26) and current or past smokers accounted for half of the patients affected (13 of 26). Screening subjects with EGFR mutations may identify patients whose tumors could respond to targeted therapy using tyrosine kinase inhibitors.  相似文献   
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