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1.
Qiaojie Wang Karan Goswami Noam Shohat Arash Aalirezaie Jorge Manrique Javad Parvizi 《The Journal of arthroplasty》2019,34(5):947-953
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2.
Ravinder K. Mittal MD Barry N. Siskind MD Michio Hongo MD M. Wayne Flye MD Richard W. McCallum MD 《Digestive diseases and sciences》1986,31(4):379-384
Three patients with dysphagia caused by compression of the distal esophagus by a tortuous nonaneurysmal atherosclerotic aorta are described. All three patients were elderly women; systemic hypertension and cardiomegaly were present in two patients. Barium studies of the esophagus showed displacement and compression of the distal esophagus by the thoracic aorta. Debilitating dysphagia was treated surgically in one patient. The other two patients had milder symptoms and were managed conservatively. Esophageal manometry in these three patients showed superimposed pulsations and elevated intraluminal pressure just proximal to the lower esophageal sphincter. To evaluate the significance of these manometric findings and their correlation with clinical symptoms, we reviewed manometric tracings in 47 normal subjects. Ten of these subjects had an elevation of baseline intraluminal esophageal pressure as a result of superimposed vascular pulsations. We conclude that (1) compression of the distal esophagus by a tortuous atherosclerotic aorta in the appropriate setting can lead to clinically significant dysphagia and (2) a manometric finding of vascular compression of the esophagus does not necessarily correlate symptomatic dysphagia. 相似文献
3.
Wang C Auerbach JD Witschey WR Balderston RA Reddy R Borthakur A 《Seminars in spine surgery》2007,19(2):65-71
The intervertebral disc is characterized by a tension-resisting annulus fibrosus, and a compression-resisting nucleus pulposus composed largely of proteoglycan. Both the annulus and the nucleus function in concert to provide the disc with mechanical stability. Early disc degeneration begins in the nucleus with proteoglycan depletion. Quantitative MRI techniques have been developed to non-invasively quantify the earliest degenerative changes that occur within the disc. Our ability to identify and quantify these early biochemical changes will provide a better understanding of the pathophysiology of disc degeneration and facilitate the study of interventions that aim to halt or reverse the degenerative process. 相似文献
4.
Norethisterone enanthate (NET-En), an established intramuscular long-acting contraceptive agent, has previously been shown to be effective in inhibiting fertility in two rodent species even 4 days after oral ingestion. Pharmacokinetics of NET and NET-En were studied after oral and intramuscular doses in two animal species and a few women. The results suggest that the NET-En was absorbed within a day in all the species after oral dose. The estimates of relative bioavailability ranged from 13 to 51% in rabbits, monkeys, and women. The elimination half-life was 5–10 days. The presence of the active component, NET, in the circulation over the experimental period of 15 days suggests that NET-En could be useful as a long-acting oral pill. The suppression of progesterone levels during the luteal phase of menstrual cycle in women also supports this finding. 相似文献
5.
Dr. Ravinder K. Mittal MD 《Digestive diseases and sciences》1991,36(9):6S-13S
The principles of infusion manometry in the measurement of lower esophageal sphincter (LES) pressure were laid down in the mid-1960s by L.D. Harris and his coworkers. Dodds and his colleagues were largely responsible for the improvements and advent of the low-compliance manometry. Using side-hole manometry, it is possible to detect accurate LES pressure that correlates with the strength of the antireflux barrier. The LES pressure as measured by the side-hole manometry, shows respiration-induced pressure oscillations. These pressure oscillations were initially thought to be due to the influence of abdominal and thoracic pressures on the LES. However, it was later pointed out that these pressure oscillations were due to the relative motion of the point pressure sensor (side hole of the manometric catheter) and the LES during respiration. Recent studies suggest that active contraction of the crural diaphragm during inspiration is responsible for the pressure oscillations observed in the cat LES pressure tracings. The use of the sleeve device in the measurement of LES pressure during contraction of the diaphragm has been described recently. Using the principles of manometry and sleeve device, it is now possible to identify two lower esophageal sphincters: the smooth muscle LES, traditionally known as the LES, and crural diaphragm, which we have referred to as the external lower esophageal sphincter. The purpose of the following paper is to summarize the general principles of the infusion manometry in the measurement of intraluminal pressure, specifically the LES pressure. The recently developed technique of detection of the sphincteric function of the crural diaphragm by the sleeve device will be discussed. In the last paragraph the limitations of manometry in detection of the muscular contractile activity are described. 相似文献
6.
Ravinder Verma 《Indian journal of otolaryngology and head and neck surgery》1996,48(4):312-314
Stylalgia is an important cause of paroxysmal dull pain in the throat and ear. Enlarged styloid process is the ossification stylohyoid ligament. Pain is aggravated by the act of deglutition. Pain due to enlarged styloid process may be attributed to the Glassopharyngeal Neuritis or stiff bony clasp formation. Styloidectomy, by any route, is a satisfactory mode of treatment in such cases. In cases with prolonged illness or no response with styloidectomy, Glassopharyngeal Neurectomy may be taken up. 相似文献
7.
Walter R T Witschey Arijitt Borthakur Mark A Elliott Eric Mellon Sampreet Niyogi Chenyang Wang Ravinder Reddy 《Magnetic resonance in medicine》2007,57(1):2-7
The origin of image artifacts in an off-resonance spin-locking experiment is shown to be imperfections in the excitation flip angle. A pulse sequence for off-resonance spin locking is implemented that compensates for imperfections in the excitation flip angle through an off-resonance rotary echo. The off-resonance rotary echo alternates the frequency offset and phase of the RF transmitter during two spin-locking pulses of equal duration. The underlying theory is detailed, and MR images demonstrate the effectiveness of the technique in agarose gel phantoms and in in vivo human brain at 3T. 相似文献
8.
9.
Detection of hydatid antigen in urine by countercurrent immunoelectrophoresis. 总被引:4,自引:0,他引:4 下载免费PDF全文
Hydatid antigen was demonstrated for the first time in the urine of patients with hydatid disease by countercurrent immunoelectrophoresis (CIEP). The antigen was detected in the concentrated urine of 7 of 16 (43.75% positive) patients with surgically confirmed hydatid disease, 4 of 10 (40% positive) patients with ultrasound-proven hydatid disease (daughter cysts or prominent septation and hydatid sands demonstrated by ultrasound), and 8 of 14 (57.14% positive) patients with clinically diagnosed (presumptive) hydatid disease. No antigen was detected in the concentrated urine from 24 patients with parasitic diseases other than hydatid disease. However, antigen was detected in 2 (8% false positive) of 25 concentrated urine samples collected from healthy control subjects (blood donors and students). These result suggest that the detection of hydatid antigen in the urine by CIEP is a simple, rapid, and noninvasive method of diagnosis of hydatid disease. 相似文献
10.
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