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931.
932.
933.
Background : The present paper addressed the issue of whether pretreatment with intravenous (IV) chemotherapy affects response rate or survival in patients receiving hepatic artery chemotherapy (HAC). Methods : Case note reviews of 164 patients treated in a teaching hospital from June 1990 to July 1996 were carried out. Results : The response rate and carcino-embryonic antigen (CEA) fall in the two groups was almost identical. There was a nonsignificant survival advantage in the non-pretreatment group. Conclusions : Previous administration of IV chemotherapy did not affect the CEA response of patients receiving HAC. 相似文献
934.
Tony M. Keaveny Tania P. Pinilla R. Paul Crawford David L. Kopperdahl Albert Lou 《Journal of orthopaedic research》1997,15(1):101-110
We sought to quantify the systematic and random errors associated with-artifacts in the platens compression test for trabecular bone. Our hypothesis was that while errors may depend on anatomic site, they do not depend on apparent density and therefore have substantial random components. Trabecular bone specimens were first tested nondestructively using newly developed accurate protocols and then were tested again using the platens compression test. Percentage differences in modulus between the techniques (bovine) proximal tibia [n = 18] and humerus [n = 17] and human lumbar spine, [n = 9] were in the range of 4-86%. These differences did not depend on anatomic site (p = 0.21) and were only weakly dependent on apparent density and specimen aspect ratio (r2 < 0.10). The mean percentage difference in modulus was 32.6% representing the systematic component of the end-artifact error. Neglecting the minor variations explained by density and specimen size (approximately 10%), an upper bound on the random error from end-artifacts in this experiment was taken as the SD of the modulus difference (±18.2%). Based on a synthesis of data taken from this study and from the literature, we concluded that the systematic underestimation error in the platens compression test can be only approximated and is in the range of 20-40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small. These errors should be considered when interpreting results from the platens test, and more accurate testing techniques should be used when such errors are not acceptable. 相似文献
935.
M H Williams J N Newton S J Frankel F Braddon E Barclay J A Gray 《Journal of epidemiology and community health》1994,48(2):188-191
OBJECTIVE--To determine the prevalence of completed elective total hip replacements in a defined elderly population. DESIGN--Cross sectional postal questionnaire survey with additional data and validation from general practice and hospital records. SETTING--Six general practices in the English counties of Avon, Somerset, and Oxfordshire. SUBJECTS--A total of 7806 patients aged 65 years and over (94.7% response). RESULTS--The overall prevalence (95% confidence intervals) of elective total hip replacement was 5.3 (4.8,5.8)% Age and sex specific prevalences were 2.7 (2.0,3.5)% in men and 4.1 (3.3,4.9)% in women aged 65-74 years, and 5.2 (4.0,6.5)% in men and 8.8 (7.6,10.0)% in women aged 75 years and over. Of the 415 patients who had received elective total hip replacement, 28.2% had required bilateral surgery, 20% had received at least one operation privately, and 13% had required revision surgery. CONCLUSION--Our results show an increased level of satisfied demand for total hip replacement in elderly people compared with earlier estimates. The increasing prevalence of hip replacement is an indicator of increasing potential demand for revision procedures. Population based surveys are required to establish the level of unmet demand for primary procedures. Differences in past surgical activity may be important in interpreting the wide variation in current surgical rates. 相似文献
936.
David A Grimes J David Grimes Lem Racacho Kylie A Scoggan Fabin Han Betty Anne Schwarz John Woulfe Dennise Bulman 《Movement disorders》2002,17(6):1205-1212
The identification of rare, large families with Parkinson's disease (PD) has provided important clues that have contributed to our understanding of this complex disorder. We have identified a large French-Canadian kindred that spans five generations consisting of more than 90 individuals. A total of 65 individuals now have been examined, had venous blood drawn, and DNA extracted. Two-point and multipoint linkage analysis was performed to assess linkage to known PD genes or loci. Within the third and fourth generations of this family there are 10 living, plus 3 deceased members with well-documented levodopa responsive parkinsonism. Autopsy results on 1 member demonstrated the loss of pigmented neurons in the substantia nigra and the presence of alpha-synuclein positive Lewy bodies. Four of the PD patients have prominent postural and kinetic tremors that preceded their parkinsonism by up to 10 years. Two other individuals within the family have prominent isolated postural and kinetic tremors without parkinsonism. The alpha-synuclein(4q21.3-23), Parkin(6q25.2-27), PARK3 (2p13), PARK4, and ubiquitin carboxy terminal hydrolase-L1 (4p14-16.3) and PARK6 and PARK7 (1p35-36) loci were excluded in this kindred using closely linked markers. The clinical and pathological features of this family are consistent with the diagnosis of PD. This family further demonstrates the known genetic heterogeneity in PD and is large enough that a genome-wide screen has been undertaken in an effort to identify a novel PD gene. 相似文献
937.
Jeffrey T Cope MD Michael C Mauney MD David Banks BS Oliver A.R Binns MD Christopher L Moore BS Jeffrey J Rentz BS Kimberly S Shockey MS R.Christoper King MD Irving L Kron MD Curtis G Tribble MD 《The Annals of thoracic surgery》1997,63(6)
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non–heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non–heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non–heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.(Ann Thorac Surg 1997;63:1664–8) 相似文献
938.
939.
David Rempel Peter J. Keir W. Paul Smutz Alan Hargens 《Journal of orthopaedic research》1997,15(3):422-426
The purpose of this study was to explore the relationship between carpal tunnel pressure and fingertip force during a simple pressing task. Carpal tunnel pressure was measured in 15 healthy volunteers by means of a saline-filled catheter inserted percutaneously into the carpal tunnel of the nondominant hand. The subjects pressed on a load cell with the tip of the index finger and with 0, 6, 9, and 12 N of force. The task was repeated in 10 wrist postures: neutral; 10 and 20° of ulnar deviation; 10° of radial deviation; and 15, 30, and 45° of both flexion and extension. Fingertip loading significantly increased carpal tunnel pressure for all wrist angles (p = 0.0001). Post hoc analyses identified significant increases (p <0.05) in carpal tunnel pressure between unloaded (0 N) and all loaded conditions, as well as between the 6 and 12 N load conditions. This study demonstrates that the process whereby fingertip loading elevates carpal tunnel pressure is independent of wrist posture and that relatively small fingertip loads have a large effect on carpal tunnel pressure. It also reveals the response characteristics of carpal tunnel pressure to fingertip loading, which is one step in understanding the relationship between sustained grip and pinch activities and the aggravation or development of median neuropathy at the wrist. 相似文献
940.