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排序方式: 共有4875条查询结果,搜索用时 31 毫秒
21.
A B Magil M L Puterman H S Ballon V Chan D S Lirenman A Rae R A Sutton 《Kidney international》1988,34(4):511-517
A number of clinical laboratory and biopsy-derived parameters were assessed for their prognostic significance in the short (24 months), intermediate (60 months) and long terms in 45 patients (43 female, 2 male) with diffuse proliferative lupus glomerulonephritis (DPGN). The factors evaluated were serum creatinine (SCr) and urinary protein at time of biopsy, initial dose of prednisone and immunosuppressive after biopsy, activity index (AI), chronicity index (CI), their individual components, extent of extraglomerular (tubulo-interstitial) immune deposits (EGD) and mean number of intraglomerular monocytes per glomerulus (NSE index). Using proportional hazards analysis to evaluate the parameters, SCr (P = 0.003), AI (P = 0.005) and NSE index (P = 0.038) were shown to be significant predictors of outcome when all variables except the components of AI and CI were considered. When AI and CI were omitted but their components included, SCr (P = 0.0005), NSE index (P = 0.024), extent of karyorrhexis (P = 0.035) and glomerulosclerosis (P = 0.033) were then demonstrated to be significant prognostic factors of DPGN. The results suggest that intraglomerular monocyte infiltration has a protective effect and confirm that AI index is a relatively powerful predictor of outcome. Histologic and nonhistologic biopsy factors contribute significant additional prognostic information to that provided by SCr. 相似文献
22.
Monophasic action potential recordings during acute changes in ventricular loading induced by the Valsalva manoeuvre.
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OBJECTIVE--The strong association between ventricular arrhythmia and ventricular dysfunction is unexplained. This study was designed to investigate a mechanism by which a change in ventricular loading could alter the time course of repolarisation and hence refractoriness. A possible mechanism may be a direct effect of an altered pattern of contraction on ventricular repolarisation and hence refractoriness. This relation has been termed contraction-excitation feedback or mechano-electric feedback. METHODS--Monophasic action potentials were recorded from the left ventricular endocardium as a measure of the time course of local repolarisation. The Valsalva manoeuvre was used to change ventricular loading by increasing the intrathoracic pressure and impeding venous return, and hence reducing ventricular pressure and volume (ventricular unloading). PATIENTS--23 patients undergoing routine cardiac catheterisation procedures: seven with no angiographic evidence of abnormal wall motion or history of myocardial infarction (normal), five with a history of myocardial infarction but with normal wall motion, and 10 with angiographic evidence of abnormal wall motion--with or without previous infarction. One patient was a transplant recipient and was analysed separately. SETTING--Tertiary referral centre for cardiology. RESULTS--In patients with normal ventricles during the unloading phase of the Valsalva manoeuvre (mean (SD)) monophasic action potential duration shortened from 311 (47) ms to 295 (47) ms (p less than 0.001). After release of the forced expiration as venous return was restored the monophasic action potential duration lengthened from 285 (44) ms to 304 (44) ms (p less than 0.0001). In the group with evidence of abnormal wall motion the direction of change of action potential duration during the strain phase was normal in 7/21 observations, abnormal in 6/21, and showed no clear change in 8/21. During the release phase 11/20 observations were normal, five abnormal, and four showed no clear change. In those with myocardial infarction four out of five patients had changes that resembled those with normal ventricles but the changes were less pronounced. There were no differences in any of the three groups between the changes in monophasic action potential duration in patients taking beta blockers and those who were not. The changes in monophasic action potential duration in the transplanted heart resembled those in the group with normal ventricles. Inflections on the repolarisation phase of the monophasic action potential consistent with early afterdepolarisations were seen in three of the patients with abnormal wall motion and in none of those with normal wall motion. CONCLUSIONS--These results are further evidence that changes in ventricular loading influence repolarisation. When wall motion was abnormal the effects on regional endocardial repolarisation were often opposite in direction to those when it was normal. Thus regional differences in wall motion could generate local electrophysiological inhomogeneity which may be relevant to the association of arrhythmia with impaired left ventricular function. 相似文献
23.
J W Gaffney F Z Bierman C M Donnelly M Sutton S Piomelli W M Gersony 《The American journal of cardiology》1988,62(1):121-125
The effect of transfusion/chelation therapy on the cardiovascular adaptations to chronic anemia in pediatric and young adult patients with homozygous sickle cell disease is uncertain. This study compares left ventricular (LV) function indexes and thoracoabdominal aortic systolic and diastolic blood flow in nontransfused and transfused patients with homozygous sickle cell disease. The study population consisted of 29 nontransfused patients with homozygous sickle cell disease, ages 0.4 to 20.9 years (group 1) and 11 chronically transfused/chelated patients, ages 4.0 to 21.8 years (group 2). The mean total hemoglobin concentration in group 2 was 28% greater than that in group 1. The mean duration of transfusion/chelation therapy in group 2 was 3.7 years. The percent of predicted LV end-diastolic and end-systolic dimensions were significantly greater than the respective controls in both groups. There was no significant difference in percent of predicted LV end-diastolic dimension (group 1, 120 +/- 12%; group 2, 120 +/- 12%) or percent of predicted LV end-systolic dimension (group 1, 120 +/- 12%; group 2, 117 +/- 8) between the groups. The percent of LV shortening fraction was similar in study groups and control subjects. Aortic systolic blood flow (cc/min/m2) for group 1 (2,426 +/- 841) and 2 (2,374 +/- 1.004) were significantly greater than corresponding control values (1,683 +/- 442, 1,736 +/- 430, respectively). Aortic diastolic blood flow was significantly greater than corresponding control values for both group 1 (699 +/- 313 vs 488 +/- 212) and group 2 (1,080 +/- 607 vs 588 +/- 219).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
24.
M J Vocci A L Robin J C Wahl P Mayer A Graves B York C Enger J Sutton 《American journal of ophthalmology》1992,113(2):154-160
We performed a prospective, double-masked, placebo-controlled, six-period, cross-over study in which normal subjects were randomly assigned to treatment and compared three different formulations of apraclonidine hydrochloride (the present commercially available formulation, and formulations with hydroxypropylmethylcellulose or lysolecithin). We also evaluated the efficacy of a 16-microliters and 30-microliters drop size. The magnitude and duration of decrease in intraocular pressure was comparable for all formulations. Most subjects tolerated all formulations well with only a few reporting any side effects. The best-tolerated formulation was 0.5% apraclonidine hydrochloride delivered with a 16-microliters drop size. Dry mouth developed frequently with the commercially available 1% apraclonidine solution. Blurred vision complicated the use of the formulation containing hydroxypropylmethylcellulose. Both dry mouth (P less than .05) and blurred vision (P = .004) were statistically significant side effects. 相似文献
25.
P K Kotylo H Michael T E Davis G P Sutton P R Mark L M Roth 《International journal of gynecological pathology》1992,11(4):245-252
The placental-site trophoblastic tumor is a rare form of gestational trophoblastic neoplasia. Although originally considered benign, it is now apparent that this lesion can be associated with aggressive clinical behavior. Our study examined the DNA ploidy status and clinicopathologic features of four new cases of placental-site trophoblastic tumor. Three cases demonstrated diploid DNA stemlines with S-phase fractions ranging from 6% to 16%. These patients were alive and well at follow-up and had low-serum human chorionic gonadotrophin (hCG) levels. A fourth patient, who had a large tumor, demonstrated a tetraploid DNA peak with a prominent S-phase fraction. This patient exhibited an elevated serum hCG at limited follow-up. Flow cytometric DNA analysis may be a useful adjunct for the identification of placental-site trophoblastic tumors with malignant potential. 相似文献
26.
27.
Periosteal Ewing sarcoma 总被引:3,自引:0,他引:3
28.
Allodynia in rats infected with varicella zoster virus—a small animal model for post-herpetic neuralgia 总被引:1,自引:0,他引:1
Robert G. Dalziel Sharon Bingham David Sutton Dawn Grant Jean M. Champion Shelley A. Dennis John P. Quinn Chas Bountra Margo A. Mark 《Brain Research Reviews》2004,46(2):234
The most common complication of herpes zoster is post-herpetic neuralgia (PHN), which has been defined as severe pain occurring 1 month after rash onset or persisting for greater than 3 months. PHN is classed as a neuropathic pain that is associated with mechanical allodynia where normally innocuous tactile stimuli are perceived as painful. The development of therapies to treat PHN has been hampered by the lack of animal models, which mimic the clinical situation. We have previously reported that varicella zoster virus (VZV) infection in the rat results in mechanical allodynia and thermal hyperalgesia. Here, we report that following VZV infection of the left footpad rats develop a chronic mechanical allodynia, which is present for longer than 60 days post-infection and which resolves by 100 days PI. The model is robust and reproducible with animals consistently developing allodynia by 3 days PI and continuing to present with symptoms for at least 30 days. The reproducible nature of the induction and course of the allodynia allows the use of this model to determine the effect of various compounds on, and to investigate the pathogenic mechanisms underlying the development of VZV-induced allodynia. Comparative studies using HSV-1 show that the induction of the chronic allodynia is VZV-specific and is not a result is of virus replication-induced tissue damage or accompanying inflammation.Therefore, we propose that the rat VZV infection model could prove useful in studying the mechanisms underlying post-herpetic neuralgia. 相似文献
29.
Christopher Sutton 《Lasers in medical science》1986,1(1):25-31
Adhesions and endometriosis are commonly encountered among patients presenting with pelvic or lower abdominal pain and also in a significant proportion of infertile patients. Laparoscopic investigation is usual in patients with these problems, and it has been possible to perform endoscopic surgery with special scissors and electrodiathermy. These methods can cause troublesome bleeding, and the diathermy produces high temperatures which can be hazardous if used in the vicinity of the bowel. The carbon dioxide laser can be used endoscopically to vaporize deposits of endometriosis and adhesions with great precision and virtually no bleeding. One hundred consecutive patients with endometriosis or adhesions were treated with the CO2 laser laparoscope and followed up for at least a year. Seventy-five per cent of patients with pain due to endometriosis were cured, and 68% of patients were better after laser laparoscopic adhesiolysis. Pregnancy rate in the previously infertile group with endometriosis was 64%. There were no complications due to the intra-abdominal use of CO2 laser energy under endoscopic control, although there is a need for a controlled trial. It appears that in the hands of an experienced laparoscopist this technique is safe and effective. 相似文献
30.
Audit of 149 consecutive carotid endarterectomies performed by a single surgeon in a district general hospital over a 12-year period. 总被引:1,自引:1,他引:0
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L. C. Tan G. L. Sutton N. J. Taffinder M. Perry T. Fail 《Annals of the Royal College of Surgeons of England》1996,78(4):340-344
Carotid endarterectomy has been established by two large randomised controlled trials (European Carotid Surgery Trial (ECST) and North American Symptomatic Carotid Endarterectomy Trial (NASCET)) as an important surgical procedure for the prevention of ischaemic strokes in patients presenting with transient cerebral ischaemia or non-disabling strokes attributable to severe ipsilateral carotid artery stenosis. The operation carries significant risk of death and stroke and it has been advocated by some that carotid endarterectomy should only be performed in a small number of designated regional centres in order to achieve good surgical results. It is doubtful that the regional centres alone can cope with the increasing numbers of patients requiring carotid endarterectomy and there is therefore a requirement for the procedure to be carried out by vascular surgeons in district general hospitals. It is important that surgical results are audited to ensure that comparable outcomes are achieved. We present an audit of our experience of carotid endarterectomy since 1981. A total of 149 consecutive carotid endarterectomies were performed by a single surgeon with a special interest in carotid surgery. The results are comparable to ECST with a 30-day mortality of 0% and an overall 30-day stroke rate of 5.7% (major strokes) for patients with severe, ie 70-99%, ipsilateral carotid artery stenoses. We have shown that carotid endarterectomy is an operation that can be performed safely and with good results by suitably trained surgeons in district general hospitals. 相似文献