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Background

Whether prolonged operative time is an independent risk factor for subsequent surgical site infection (SSI) and periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant and underexplored issue. The aim of this study is to investigate the association between operative time and the risk of subsequent SSI and PJI in patients undergoing primary TJA.

Methods

We retrospectively reviewed 17,342 primary unilateral total knee arthroplasty and total hip arthroplasty performed at a single institution between 2005 and 2016, with a minimum follow-up of 1 year. A multivariate logistic regression model was conducted to identify the association between operative time and the development of SSI within 90 days and PJI within 1 year.

Results

Overall, the incidence of 90-day SSI and 1-year PJI was 1.2% and 0.8%, respectively. Patients with an operative time of >90 minutes had a significantly higher incidence of SSI and PJI (2.1% and 1.4%, respectively) compared to cases lasting between 60 and 90 minutes (1.1% and 0.7%), and those lasting ≤60 minutes (0.9% and 0.7%, P < .01). In the multivariate model, the risk for infection increased by an odds ratio of 1.346 (95% confidential interval 1.114-1.627) for 90-day SSI and 1.253 (95% confidential interval 1.060-1.481) for 1-year PJI for each 20-minute increase in operative time.

Conclusion

In patients undergoing primary TJA, each 20-minute increase in operative time was associated with nearly a 25% increased risk of subsequent PJI. We advocate that surgeons pay close attention to this underappreciated risk factor while maintaining safe operative practices, which minimize unnecessary steps and wasted time in the operating room.  相似文献   
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Studies were undertaken to compare the effect of poly(A)s from various sources on selective inhibition of protein synthesis in the reticulocyte lysate system programmed with viral and cellular mRNAs. RNA synthesized in vitro by vaccinia virus cores in the presence of only ATP inhibited overall HeLa cell polypeptide synthesis by over 80% with a minimal effect on translation of vaccinia virus mRNAs. Hybridization of the [alpha-32P]AMP-labeled RNA made in vitro by vaccinia virus cores in the presence of only ATP, showed no complementary to HindIII restriction fragments of vaccinia virus DNA indicating that the in vitro product was poly(A). Fractionation of synthetic and core-synthesized poly(A) into three size classes showed that the larger the size of poly(A), the greater its inhibitory activity of protein synthesis in the cell-free system. Inhibition of translation of mRNAs from vaccinia virus-infected HeLa cells was also observed in the presence of poly(A). However, virus-induced polypeptide synthesis was more resistant to the effect of poly(A) than were cellular polypeptides. Oligo(dT) when added to the reticulocyte lysate system was capable of reversing the inhibition of protein synthesis caused by both core-synthesized poly(A) and core-transcribed RNAs. These results indicate that poly(A) synthesized by the virion-associated enzyme has inhibitory properties similar to those of synthetic poly(A).  相似文献   
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Premature ovarian failure   总被引:9,自引:0,他引:9  
Premature ovarian failure (POF) causing hypergonadotrophic hypogonadism occurs in 1% of women. In majority of cases the underlying cause is not identified. The known causes include: (a) Genetic aberrations, which could involve the X chromosome or autosomes. A large number of genes have been screened as candidates for causing POF; however, few clear causal mutations have been identified. (b) Autoimmune ovarian damage, as suggested by the observed association of POF with other autoimmune disorders. Anti-ovarian antibodies are reported in POF by several studies, but their specificity and pathogenic role are questionable. (c) Iatrogenic following surgical, radiotherapeutic or chemotherapeutic interventions as in malignancies. (d) Environmental factors like viral infections and toxins for whom no clear mechanism is known. The diagnosis is based on finding of amenorrhoea before age 40 associated with FSH levels in the menopausal range. Screening for associated autoimmune disorders and karyotyping, particularly in early onset disease, constitute part of the diagnostic work-up. There is no role of ovarian biopsy or ultrasound in making the diagnosis. Management essentially involves hormone replacement and infertility treatment, the only proven means for the latter being assisted conception with donated oocytes. Embryo cryopreservation, ovarian tissue cryopreservation and oocyte cryopreservation hold promise in cases where ovarian failure is foreseeable as in women undergoing cancer treatments.  相似文献   
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The Competencies Conference: Future Directions in Education and Credentialing in Professional Psychology was held in Arizona in November 2002. One of the workshops, Individual and Cultural Differences (ICD), focused on racism, homophobia, and ageism. The consensus was that self-awareness and knowledge about the three "isms" are critical components in the education and training of psychologists. This article, authored by four of the workshop attendees, is a review of the current research and theoretical literature. Implications that address both content and context in graduate programs and training sites are presented. This is one of a series of articles published in this issue of the Journal of Clinical Psychology. Several other articles that resulted from the Competencies Conference will appear in Professional Psychology: Research and Practice and The Counseling Psychologist.  相似文献   
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Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), caused by Leishmania donovani, is difficult, as the dermal lesions are of several types and resemble those caused by other skin diseases, especially leprosy. Since the disease generally appears very late after the clinical cure of kala-azar in India, it is also difficult to correlate PKDL with a previous exposure to L. donovani. Very few attempts have been made so far to diagnose PKDL serologically, and the diagnostic methods vary in their sensitivities and specificities. Diagnosis of PKDL through sophisticated PCR methods, although highly sensitive, has limited practical use. We have developed a serodiagnostic method using an enzyme-linked immunosorbent assay to detect specific immunoglobulin (Ig) isotypes and IgG subclass antibodies in the sera of Indian PKDL patients. Our assay, which uses L. donovani promastigote membrane antigens, was 100% sensitive for the detection of IgG and 96.7% specific for the detection of IgG and IgG1. Optical density values for individual patients, however, demonstrated wide variations. Western blot analysis based on IgG reactivity could differentiate patients with PKDL from control subjects, which included patients with leprosy, patients from areas where kala-azar is endemic, and healthy subjects, by the detection of polypeptides of 67, 72, and 120 kDa. The recognition patterns of the majority of serum samples from patients with PKDL were also distinct from those of the serum samples from patients with visceral leishmaniasis (VL), at least for a 31-kDa polypeptide. To further differentiate patients with PKDL from those with active and cured VL, we analyzed the specific titers of the Ig isotypes and IgG subclasses. High levels of IgG, IgG1, IgG2, and IgG3 antibodies significantly differentiated patients with PKDL from patients cured of VL. The absence of antileishmanial IgE and IgG4 in patients with PKDL differentiated these patients from those with active VL. These results imply intrinsic differences in the antibodies generated in the sera from patients with PKDL and VL.  相似文献   
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The US Food and Drug Administration approved a 6-month regimen of pretomanid, bedaquiline, and linezolid for extensively drug-resistant or multidrug-intolerant tuberculosis after a trial in South Africa demonstrated 90% effectiveness 6 months posttreatment. We report on a patient who completed the regimen using a lower linezolid dose.  相似文献   
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During 1981-1991 at a rural teaching hospital (Kasturba Hospital) of Mahatma Gandhi Institute of Medical Sciences in Sevagram, Wardha, India, 454 of 13,939 newborns died during the early neonatal period for an early neonatal mortality rate (ENMR) of 33.7/1000 live births. The ENMR for boys was not significantly different from that for girls (36.1 vs. 28.6). Community medicine specialists analyzed data on these early neonatal deaths to examine distribution of early neonatal mortality, especially its relationship with prematurity, low birth weight, birth order, and by sex. They calculated average percent deaths (APD) per hour to examine the dynamics in early neonatal mortality. The mean age at death was lower among newborns of birth order greater than 2 than those of birth order less than 2 (23.47 vs. 26.85 hours; p 0.001). ENMR was higher for newborns of birth order greater than 2 than those of birth order less than 2 (41.74% vs. 27.35%; P 0.001). The mean age at death increased as gestation increased (10.34 for 28 weeks; 24.27 for 28-33 weeks, 31.53 for 33-37 weeks, and 34.43 for 37 weeks; p 0.001). ENMR decreased as gestation increased (850 for 28 weeks; 375 for 28-33 weeks, 147.02 for 33-37 weeks, and 8.77 for 37 weeks; p 0.001). The mean age at death increased as birth weight increased for newborns weighing less than 1500 gms through 2000-2500 gms (23.36-37.13 hours; p 0.001). It was lowest among those weighing more 3000 gms (11.55 gms). ENMR fell as birth weight increased (614.33 for 1500 gms, 116.19 for 1500-2000 gms, 19.38 for 2000-2500 gms, 10.99 for 2500-3000 gms, and 5.41 for 3000 gms; p 0.001). The APD/hour for the first hour of life was 3.74% for a relative risk of 12.9. It decreased steadily as the hours of life increased (3.08% for 1-6 hours, 1.19% for 6-24 hours, 0.67% for 24-72 hours, and 0.29% for 72-168 hours). Knowledge of time of likely death can help providers know where they need to focus their attention to prevent early neonatal deaths.  相似文献   
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