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81.
基于光电传感器的多段脉搏波传播速度检测系统的研制   总被引:2,自引:4,他引:2  
采用了一种以反射式和透射式红外光光电传感器和单片机为基础,用同步检测心电信号、桡动脉脉搏波、手指脉搏波信号来测定桡动脉和外周动脉脉搏波传播速度的方法,研制一种无创的多段脉搏波传播速度检测系统。在软件编程中脉搏波周期信号的识别是以心电R波峰值为基准,同时再根据它们之间的时延关系进一步确定脉搏波的波峰与波谷的范围,提高检测准确性及精度。该系统通过检测心电、桡动脉脉搏波和手指脉搏波信号可获得多段脉搏波传播速度参数,具有较高的检测精度和良好的应用前景。  相似文献   
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84.
To study the relationship between nocturnal blood pressure (BP) variation and spontaneous intracerebral hemorrhage (ICH) among Chinese hypertensive patients and its clinical significance, the authors retrospectively screened 371 patients with primary hypertension (189 patients with ICH, 182 patients without ICH) in Shanghai and analyzed their demographics, clinical information, nocturnal blood pressure variability and medication. Compared with the control group, the levels of blood glucose, triglycerides, and creatinine were significantly increased in the ICH group, along with a marked reduction in nocturnal BP drop (P<.05). Multivariate logistic regression indicated that blood glucose, creatinine, and nocturnal mean arterial pressure were risk factors for ICH, and the magnitude of nocturnal BP drop was negatively related to the risk for ICH. There was no significant difference in the prevalence of reverse dippers between the large hematoma volume group and the small hematoma volume group (χ2=2.529, P=.112), nor among the patients taking angiotensin‐converting enzyme inhibitors, angiotensin receptor blockers, or calcium channel blockers (χ2=1.981, P=.371). Reverse dipping is associated with the risk for ICH, suggesting that appropriate antihypertensive drug and chronotherapy might be effective to normalize the rhythm of abnormal circadian variation in hypertensive patients.  相似文献   
85.
Failure to deliver stents is one of the commonest causes of procedural failure in contemporary PCI practice. We describe successful use of the Guideliner Catheter, the first purpose designed FDA and CE marked device delivery catheter in 13 complex cases in native coronary vessels and bypass grafts performed via the radial route to enable distal stent delivery following failure of conventional techniques. We discuss how the Guideliner catheter may be used to facilitate difficult radial cases. © 2010 Wiley‐Liss, Inc.  相似文献   
86.

Objectives

Facial lipoatrophy can be a stigmatizing side effect of antiretroviral (AVR) treatment for HIV‐infected patients. We sought to evaluate the long‐term efficacy and safety of a new formulation of hyaluronic acid that can be injected in larger amounts and into deeper skin layers during 3 years of follow‐up.

Methods

Twenty patients received injections of Restylane SubQ. Refill treatment was offered at 12 and 24 months. Treatment effects were evaluated using ultrasound, the Global Aesthetic Improvement Scale, visual analogue scale (VAS) and the Rosenberg self‐esteem scale.

Results

Seventeen patients remained at 36 months. Mean (± standard deviation) total cutaneous thickness increased from 6 ± 1 mm at baseline to 12 ± 1 mm (P<0.001) at 36 months. Response rate (total cutaneous thickness >10 mm) was 70%. Fifteen patients classified their facial appearance as very much or moderately improved. VAS increased from 39 ± 25 to 70 ± 20 (P<0.05) and higher self‐esteem scores were reported. Local swelling and tenderness after treatment was common. Persistent papules found in several patients after treatment were removed effectively with hyaluronidase injections. Three patients, treated only at baseline, still had higher total cutaneous thickness scores at 36 months.

Conclusions

Our results indicate that a large particle hyaluronic acid formulation is a durable and well‐tolerated dermal filler for treating HIV‐positive patients with facial lipoatrophy.
  相似文献   
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88.
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment.  相似文献   
89.
During the next several decades, the aging of the "baby boom" generation in the United States will result in a dramatic increase in the number of patients aged 65 and older seeking medical care, but current projections suggest that the shortage of geriatrics-trained specialists will only worsen during this time period. As a result, the care of elderly patients will largely fall to other types of physicians. Consequently, it is imperative that medical school training include exposure to the basic skills needed to care safely for older adults. This goal is challenging, because the number of geriatric medicine faculty in most academic medical centers is small, and multiple other medical specialties are also vying for time in a busy medical school curriculum. Whether a 3-day course conducted during the third year of medical school could teach basic principles of geriatric medicine in a time- and manpower-effective manner was explored. It was found that even this brief exposure to geriatrics could have meaningful effects on student knowledge of and comfort with geriatrics.  相似文献   
90.
Total joint replacement has been one of the most remarkable successes of modern medical technology. Once John Charnley had solved the problems of implant design, choice of materials, implant fixation, and infection (initial rates of infection were approximately 10%), the way was clear for the widespread use of this valuable treatment, which is highly effective at removing pain and restoring function. Unfortunately, infection still remains an important, though less common, problem. It is associated with serious morbidity (pain, loss of function, wound breakdown, wound discharge, implant failure) and sometimes mortality. It may be impossible to eradicate or suppress infection in the long term without removal of the prosthesis, and most clinicians would consider it unwise to re-implant a new prosthesis in the presence of infection. Hence, patients with infected prosthetic joints generally require multiple additional operations and prolonged periods of antibiotic therapy. Even radical attempts at cure may fail (in 10% to 15% of cases in most series), requiring further cycles of treatment with progressively deteriorating function. Thus, the treatment of prosthetic joint infection is arduous for the patient and the health care team, with no guarantee of success.  相似文献   
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