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161.
《Physiotherapy》1997,83(6):284-289
This paper describes a method of systematic reviewing. This method puts much emphasis on the methodological quality of the randomised clinical trials involved. Various items concerning the internal validity, precision and relevance of the studies are scored in such a way that next to the methodological quality the amount of uncertainty about it also becomes visible. These quality assessments are not only useful for systematic reviews, but also have an educational function for researchers with respect to the design and publication of a clinical trial. 相似文献
162.
163.
R S Nanra 《Nephrology, dialysis, transplantation》1992,7(5):384-390
Comprehensive renal function tests were performed in 84 patients with analgesic nephropathy, 33 glomerulonephritis patients matched for creatinine clearance, and 30 control subjects. A system of 1-day renal function tests including urine microscopy, creatinine clearance, phenolsulphonphthalein excretion, urine concentration and acidification, and electrolyte excretion, was used. Patients with analgesic nephropathy were found to have significant sterile pyuria and haematuria, even those with mild renal insufficiency, significantly reduced concentrating ability and a distal acidifying defect, and a tendency to impaired sodium conservation. These function defects are consistent with the primary lesion of renal papillary necrosis in analgesic nephropathy; the detection of these defects have implications in patient management. 相似文献
164.
The clinical potential of computer assisted surgery (W) has been more and more widely acknowledged since CAS systems have been introduced into the operating room (OR) theater.
Especially the improvements in safety and accuracy are remarkable and strengthen the ties between surgeons and engineers. Tumor stereotaxis was introduced to neurological surgery in the early 1980s, and currently systems with and without robotic navigation are in use for specific medical indications. Recently, solutions for computer assisted orthopedic surgery were developed and applied to various anatomical regions. However, with the establishment of CAS in vivo, a new complex of problems, which was not present in the laboratory setup, was introduced: the man-machine interface.
Currently, the complexity of available CAS systems requires the presence of at least one system engineer (often called the “operator”) in the OR. As a consequence, there is no possibility for direct communication between the surgeon and the machine or software.
Most of the program steps involved in CAS and choices to be made intraoperatively have to be transferred to the software by means of communication of the surgeon with the operator. Particularly, the establishment of a relation between the virtual object (i.e., a medical image) and the surgical object (i.e., the patient), often denoted as “matching” or “skeletal registration” requires intensive interaction of the surgeon with the computer. A literature survey revealed that no CAS system in clinical use exists without a system engineer or a comparable person, and our clinical experience indicated that the matching process is a weak point in most systems. Because it appears to be contradictory to cost-reduction efforts in health care to have a highly paid specialist in the OR, this research evaluates strategies to facilitate the man-machine interface with the final goal of establishing a direct control of the system by the surgeon or the medical personnel traditionally present at surgery. Options to be investigated include 1) a CAS control panel (virtual keyboard) as an integrated component of the existing navigation system and 2) introduction of a commercial voice-recognition system. The implementation of these strategies into the existing CAS setup at the Department of Orthopaedic Surgery at the Inselspital (University of Bern) and clinical experience gained are reported 相似文献
Especially the improvements in safety and accuracy are remarkable and strengthen the ties between surgeons and engineers. Tumor stereotaxis was introduced to neurological surgery in the early 1980s, and currently systems with and without robotic navigation are in use for specific medical indications. Recently, solutions for computer assisted orthopedic surgery were developed and applied to various anatomical regions. However, with the establishment of CAS in vivo, a new complex of problems, which was not present in the laboratory setup, was introduced: the man-machine interface.
Currently, the complexity of available CAS systems requires the presence of at least one system engineer (often called the “operator”) in the OR. As a consequence, there is no possibility for direct communication between the surgeon and the machine or software.
Most of the program steps involved in CAS and choices to be made intraoperatively have to be transferred to the software by means of communication of the surgeon with the operator. Particularly, the establishment of a relation between the virtual object (i.e., a medical image) and the surgical object (i.e., the patient), often denoted as “matching” or “skeletal registration” requires intensive interaction of the surgeon with the computer. A literature survey revealed that no CAS system in clinical use exists without a system engineer or a comparable person, and our clinical experience indicated that the matching process is a weak point in most systems. Because it appears to be contradictory to cost-reduction efforts in health care to have a highly paid specialist in the OR, this research evaluates strategies to facilitate the man-machine interface with the final goal of establishing a direct control of the system by the surgeon or the medical personnel traditionally present at surgery. Options to be investigated include 1) a CAS control panel (virtual keyboard) as an integrated component of the existing navigation system and 2) introduction of a commercial voice-recognition system. The implementation of these strategies into the existing CAS setup at the Department of Orthopaedic Surgery at the Inselspital (University of Bern) and clinical experience gained are reported 相似文献
165.
目的:探讨胃复春片治疗慢性胃病患者前后生长抑素内分泌细胞(D细胞)数量变化。方法:用免疫组化酶链亲合素过氧化酶复合技术(SABC)对患者治疗前后胃粘膜组织的D细胞染色,观察治疗前后D细胞的形态和数量变化。结果:经胃复春片治疗后,患者胃窦粘膜D细胞阳性数及强阳性率均明显下降,有显著意义。结论:胃复春片对慢性胃病患者生长抑素D细胞有调整作用。 相似文献
166.
本文简述了中药炮炙的根据、原理、方法以及各种不同辅料和炮炙方法对饮片药性与作用的影响。说明不同的炮炙方法可以直接影响和改变中药的药性和作用,影响到临床疗效,因此,必须重视中药饮片的炮炙工作。以确保临床安全有效的用药。 相似文献
167.
Scott A. Syverud MD J. Matthew Jenkins MD Robert A. Schwab MD Michael T. Lynch MD Kevin Knoop MD Alexander Trott MD 《Academic emergency medicine》1994,1(6):509-513
Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant. 相似文献
168.
Summary
The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic
resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF)
technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences,
the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull
base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For
a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment
of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First,
the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference
to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically
acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution,
measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the
bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose
injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of
the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials
of CE-MRA procedures.
相似文献
169.
Ilkka Sinisaari Hannu Pätiälä Ole Böstman E. Antero Mäkelä Esa K. Partio Eero Hirvensalo Pertti Törmälä Pentti Rokkanen 《Journal of orthopaedic science》1997,2(2):88-92
Between November 1984 and January 1994 in our department, a total of 2500 patients were treated with totally absorbable internal
fixation devices. We studied these patients and analyzed results with regard to the volume of the absorbable implants and
the development of wound infection. Of the 2500 patients 2044 were trauma patients and 456 were operated on for orthopedic
disease. In 1466 patients treated with implants made of self-reinforced polyglycolic acid (SR-PGA) only, the patients who
developed wound infection had a higher implant volume (P=0.07) than those who did not; this difference was close to statistical significance. In the 446 patients who received only
implants made of self-reinforced poly-l-lactic acid (SR-PLLA), the 5 who developed wound infection had a mean implant volume more than three times that of the non-infected
patients (P=0.01). We found that in the patients treated with the earlier SR-PGA implants, which contained a green staining material,
there was no correlation between implant volume and incidence of wound infections. On the other hand, both the non-stained
SR-PGA implants, which have been in clinical use since 1989, and the SR-PLLA implants, seem to be more predictable in terms
of wound infections. We believe that this difference, is largely due to the lower level of tissue reactions with these newer
implants. 相似文献
170.
This paper examines the use of videotape simulation as a research method for the exploration of clinical problem-solving, the challenges posed and the strategies employed to overcome the difficulties encountered are discussed. The simulation forms part of a larger comparative study of outcomes of pre-registration nurse education programmes, commissioned by the English National Board for Nursing, Midwifery and Health Visiting. 相似文献