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At least 109 records · Page 6Linked to original sources
PubMed1995

Implant survival rates in partially edentulous patients: a 3-year prospective multicenter study.

PURPOSE: This multicenter investigation is an interim 3-year survival report of a 5-year prospective study using Brånemark osseointegrated implants in partially edentulous patients. MATERIALS AND METHODS: Previously defined patient characteristics and clinical parameters were related to implant survival using lifetable analysis. RESULTS: Three years after prosthesis insertion, 460 implants placed in 139 patients remained in the study. Cumulative success rates for maxillary implants (92.5%) were less than for mandibular implants (94.8%), with an overall cumulative success rate of 93.9%. CONCLUSION: Failures were associated with poor bone quality, smaller implant sizes, and a higher plaque index, and were more likely to occur before loading. A 4% incidence of residual long-term inferior alveolar nerve paresthesia was higher than previously reported.

Adolescent↗
PubMed1992

[An epidemiogenetic study of typical retinitis pigmentosa in Japan--a preliminary report of nationwide, multicenter study].

We performed a nationwide, multicenter study of typical retinitis pigmentosa with reference to the inheritance patterns of the disease. A total of 253 probands were registered during two months of 1989, and an analysis of the parental consanguinity of 182 probands with the method of inbreeding coefficient enabled us to estimate the relative prevalence of genetic types; autosomal recessive trait: 47.6%; autosomal dominant trait: 17.3%; sporadic cases: 34.6%. A comparison of the results with previous studies has indicated a decrease in the prevalence of the autosomal recessive trait and an increase in the sporadic cases, as would be expected from the decrease in consanguineous marriages and offsprings in the past few decades in Japan. X-linked retinitis pigmentosa was rarely identified, but precise evaluation of its frequency needs further investigation.

Adolescent↗
PubMed1990

Angiographic assessment of patency and reocclusion: preliminary results of the Dutch APSAC Reocclusion Multicenter Study (ARMS).

The main objective of the ARMS (APSAC Reocclusion Multicenter Study) trial was to obtain patency and reocclusion data. In an open multicenter study, a total of 156 patients were treated with 30 U of anistreplase or anisoylated plasminogen streptokinase activator complex (APSAC) within 4 h after onset of pain. Patency of the infarct-related vessel was assessed by coronary angiography performed 90 minutes after anistreplase administration. In those patients with a patent infarct-related vessel at 90 min, repeat coronary angiography was performed at 24 h to assess the reocclusion rate. Two independent cardiologists evaluated the angiograms and scored the coronary artery perfusion of the infarct-related vessel. The preliminary data of the first 148 patients indicate that the patency rate at 90 min was 73-75% and the reocclusion rate at 24 h was 4%. This patency rate corresponds with previous studies. The low reocclusion rate is noteworthy and probably reflects the prolonged action of anistreplase.

Acute Disease↗
PubMed1992

Distributed data analysis in a multicenter study: the CARDIA Study.

Unlike distributed data entry, which is used in many large epidemiologic studies and multicenter clinical trials, distributed data analysis is a relatively new concept. This paper reports on the usefulness of such a system in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. CARDIA distributes the entire examination dataset to participating centers soon after completion of each round of data collection. The process was designed to encourage more numerous, diverse, and rapid publications, and to allow for more efficient use of the manpower and expertise in centers. Responsibilities of the coordinating center have changed from a conventional coordinating center but remain substantial due to the need for collating, monitoring, verifying, and documenting the distributed data analysis (DDA) system. DDA is successful from the standpoint of implementation and operation--21 manuscripts representing work analyzed at six participating centers had been submitted for publication within 3.5 years of the completion of the baseline examination.

Adolescent↗
PubMed1991

Quality control in antimicrobial disk susceptibility testing: a Belgian multicenter study.

A Belgian multicenter trial was conducted to evaluate problems encountered with quality control results of antimicrobial disk susceptibility testing and to compare the performance of BBL disks and Rosco tablets. Over a period of four weeks 18 laboratories daily tested three reference strains against eight antibiotics. A standardised method was used by all participants. For all results together 10.4% and 7.3% of the measurements with BBL disks and Rosco tablets, respectively, were outside the recommended range. Major problems were observed for some specific strain-antibiotic combinations. Standard deviations were similar for both systems; their precision was comparable. The results suggest that cooperation between manufacturers and some reference laboratories could be improved in order to establish optimal quality control limits.

Anti-Bacterial Agents↗
PubMed1985

Conference on insulin pump therapy in diabetes. Multicenter study of effect on microvascular disease. The Central Biochemistry Laboratory in the Multicenter Kroc Study. Problems and proposals.

The advantages of a multicenter trial can easily be lost if results from individual centers cannot be safely combined for statistical analysis. One objective of the Kroc Study was to develop methods that would allow valid amalgamation of results from laboratories at the six clinical centers and a central biochemical laboratory at the University of Newcastle upon Tyne. Responsibilities of the local laboratories, in addition to measurement of plasma glucose, creatinine, and glycosylated hemoglobin, were to obtain and prepare samples for measurement of plasma glucose, glycosylated hemoglobin, and serum lipids at the central laboratory, of C-peptide at the University of Chicago, and to collect and prepare samples for measurement of urinary albumin excretion at Guy's Hospital. The central laboratory was additionally to provide a system to ensure the comparability of plasma glucose determinations between and within centers, and to advise on common procedures for sample handling. Major problems were encountered with sample labeling, dispatch, and transport to the central laboratory. Although central determinations of plasma glucose and serum lipids were still possible in transported specimens, central assay of glycosylated hemoglobin proved inaccurate and useless. Compliance with the plasma glucose quality control program was variable among centers. Although the difference between the centers recording the highest and lowest values was 24.6% of the mean estimate of plasma glucose level, correlation between local and central plasma glucose determinations was good (r = 0.99, see pages 22-26).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗
PubMedDate not supplied

[The recurrence of duodenal ulcer in patients undergoing treatment with ranitidine and placebo. A multicenter study].

This randomised, double-blind multicenter study was conducted in order to evaluate the long-term effect (one year) of 150 mg ranitidine vs placebo in 51 patients with healed duodenal ulcer. Seventeen patients had ulcer recurrence at the end of follow-up, one among the 24 patients that received ranitidine and 16 among the 27 patients that received placebo (p = 0.00009). No side effects was detected. Our results support the usefulness of a one-year maintenance therapy with 150 mg ranitidine.

Adult↗
PubMed1992

Endoscopic release of the carpal tunnel: a randomized prospective multicenter study.

A 10-center randomized prospective multicenter study of endoscopic release of the carpal tunnel was carried out. Surgery was performed with a new device for transecting the transverse carpal ligament while control hands were treated with conventional open surgery. There were 122 patients in the study; 25 had carpal tunnel surgery on both hands and 97 had surgery on one hand. Of the surgical procedures, 65 were in the control group and 82 were in the device group. The endoscopic device was coupled to a fiberoptic light and a video camera. A trigger-activated blade was used to incise the transverse carpal ligament. After surgery, the best predictors of return to work and to activities of daily living were strength and tenderness variables. For patients in the device group with one affected hand, the median time for return to work was 21 1/2 days less than that for the control group. Two patients treated with the endoscopic device required reoperation by open surgical decompression; only one of these had incomplete release with the device. Two patients in the device group experienced transient ulnar neurapraxia.

Activities of Daily Living↗
PubMed1992

[Clinical and prognostic significance of echocardiographic parameters in dilated cardiomyopathy: a prospective study on 225 patients. The Italian Multicenter Study of Cardiomyopathies Group].

To assess the prognostic role of echocardiographic indexes and their relation to clinical conditions, 225 patients with dilated cardiomyopathy were studied prospectively. All cases had a normal coronary angiogram and non specific endomyocardial biopsy findings. 163 men (72.4%) and 62 women (27.6%), mean age 41.5 +/- 12.3 (range 8-61), were studied. Clinical, electrocardiographic and echocardiographic parameters, normalized for body surface area, were tested according to NYHA class and presence of segmental or diffuse wall motion abnormalities. One hundred-four patients were in NYHA class I-IIa, 94 were in class IIb-III and 27 were in class IV. Left ventricular end systolic diameter index, right ventricular end diastolic diameter index, left atrial diameter index, left ventricular fractional shortening and ejection fraction, and radius to wall thickness ratio were significantly more impaired in patients with more severe symptoms. Twenty-eight patients (13%) showed segmental wall motion abnormalities and had smaller left ventricular end systolic and left atrial diameter index and higher left ventricular fractional shortening and ejection fraction. During a mean follow up of 23 +/- 15 months (range 1-67 months), 25 patients (11.1%) died from cardiac causes and 16 (7.1%) underwent heart transplant because of refractory heart failure. Prognostic evaluation was performed separately for cardiovascular mortality alone and for cardiac events (cardiovascular mortality and heart transplantation). At Cox multivariate analysis only right ventricular end diastolic diameter index (p < 0.005) predicted cardiovascular mortality, while left atrial diameter index (p < 0.001), right ventricular end diastolic diameter index (p < 0.01) and left ventricular ejection fraction (p < 0.05) were significant independent predictors of cardiac events.

Adolescent↗
PubMed1995

The efficacy of cyclosporine A in adult nephrotic syndrome with minimal change disease and focal-segmental glomerulosclerosis: a multicenter study in Korea.

A multicenter prospective study conducted in four university hospitals in Korea investigated the efficacy and tolerance of cyclosporine A (CyA, Sandimmun) in 30 patients with adult nephrotic syndrome [25 patients with minimal change disease (MCD) and 5 with focal-segmental glomerulosclerosis (FSGS)]. After a 6-week washout period, CyA 5 mg/kg/day and prednisolone 10 mg/day were administered for up to 8 months, depending on responses to CyA. The rate of relapse after withdrawal of CyA was assessed up to 10 months. Of the 30 patients enrolled, 3 withdrew prematurely due to adverse events. Of the 27 patients who completed the study, 22 had MCD and 5 had FSGS. The prior steroid responses of these patients were 19 steroid-dependent (SD), 4 frequent-relapser (FR) and 4 steroid-resistant (SR) type. High rates of complete remission were obtained after CyA treatment in both MCD and FSGS patients, 86.4% (19/22) and 80% (4/5) respectively. Previous steroid responses did not affect the response to CyA; complete remission was obtained in 84.2% (16/19) of SD patients and in 75% (3/4) of SR patients. The mean (+/- SEM) duration of CyA treatment to attain complete remission in SD and SR patients was 3.8 (+/- 0.6) weeks and 10.7 (+/- 2.7) weeks, respectively (not significantly different). Tapering or withdrawal of CyA was followed by release of nephrotic syndrome in many patients, and the cumulative relapse rates at month 10 were 68.4% (13/19) in MCD patients and 50% (2/4) in FSGS patients. When considered according to prior steroid responses, the relapse rate was 73.3% (11/15) in SD patients and 50% (2/4) in SR patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Do steroid-eluting electrodes really have better performance than other state-of-the-art designs? The Italian Multicenter Study Group on Low Output Stimulation.

A multicenter study evaluated the performance of atrial and ventricular unipolar leads with porous steroid-eluting and platinized grooved electrodes. A total of 563 leads were implanted in 451 patients. These included 311 ventricular and 97 atrial steroid-eluting electrodes; and 112 ventricular and 43 atrial leads with platinized electrodes. Mean follow-up was > or = 1 year. At implant there were no significant differences in threshold parameters in either chamber. Chronically, however, the steroid-eluting lead consistently had significantly lower pacing thresholds in both chambers. For example, after 360 days implant, steroid-eluting electrodes had 0.23 +/- 0.10 msec ventricular thresholds at 0.8 V compared to 0.45 +/- 0.3 msec in the platinized group (P < 0.0001). In the atrium, the steroid-eluting lead's 6-month thresholds at 0.8 V were 0.15 +/- 0.06 msec compared to 0.9 +/- 0.8 msec for the platinized electrode (P < 0.01). The chronic ventricular QRS amplitudes were significantly greater for the steroid-eluting electrode (P < 0.0005). There were no significant differences in atrial sensing and no incidence of atrial undersensing in the study. The low and consistent thresholds of the steroid-eluting electrodes would have permitted pacing in the ventricle at < or = 2.5 V without compromising safety factor in 99.4% of the patients. The other 0.6% required 5 V temporarily. In the atrium, 100% of the patients could have been paced safely at reduced output. In spite of this, 63% of the implanters lacked the confidence to use reduced outputs.

Dexamethasone↗
PubMed1990

Comparison of different schedules of cytostatic intravesical instillations in patients with superficial bladder carcinoma: final evaluation of a prospective multicenter study with 419 patients.

In a prospective multicenter study we compared the value of various protocols of mitomycin C and doxorubicin instillation for the prevention of recurrent tumors in patients whose superficial bladder tumors (stages TA and T1) had been removed by transurethral resection. The 3-year and short-term instillation protocols were compared to each other and to a combination of 2 protocols. Evaluation after a mean followup of 28 months confirmed the value of cytostatic bladder instillation in preventing recurrence and progression of tumor in patients with superficial bladder carcinoma. There was no significant difference between the results of long-term and short-term prophylaxis; their combination achieved the best results. Doxorubicin and mitomycin yielded similar results; mitomycin was better tolerated.

Administration, Intravesical↗
PubMed1989

Arthroscopic drainage in septic arthritides of the knee: a multicenter study.

The results are presented of a multicenter study, conducted by questionnaire, of 46 cases of septic arthritis of the knee treated by arthroscopic drainage. This series consisted of 28 male and 16 female patients. Two patients had bilateral arthritides. The average follow-up period was 7.1 months. There were 11 cases of hematogenous arthritides, 15 arthritides secondary to puncture and infiltration, and 20 postoperative arthritides. There were 29 positive cultures (63%). After thorough articular lavage (average, 7 L) and prolonged antibiotic therapy (average 2 months) there were 36 bacteriological cures (78.3%), five failures (10.9%) due to persistent articular sepsis, and five recurrences of the infection (10.9%) after an initial remission. Five infectious flare-ups recovered secondarily, four recovered after repeated arthroscopy and one recovered after synovial centesis. The rate of cure after this second therapeutic attempt was 89.2%. Different parameters were used in evaluating the quality of the results: the etiology of the arthritis, the causal germ, and the delay prior to arthroscopy. Arthroscopic drainage is a method that has proved effective, with minimal morbidity, in attempts to cure septic arthritis of the knee, particularly in cases of hematogenous arthritis. This method could also be effective in total arthroplasties of septic knees.

Adolescent↗
PubMed1991

Treatment of angina pectoris with isosorbide-5-mononitrate. A multicenter study in general practice.

In this multicenter study 191 practitioners treated 532 patients with coronary artery disease and chronic stable angina pectoris by isosorbide-5-mononitrate (IS-5-MN), 20 mg 2-3 times daily. At the end of this period the frequency of anginal attacks was reduced by 83% and nitroglycerin consumption by 85.7% (p less than 0.0001). 40.1% of the patients categorized this treatment as very good, 28.6% as excellent and 23% as good. Serious adverse effects were observed in 2% of the patients and 6.4% of the patients discontinued treatment during the study because of inefficacy, infarction, death, or adverse effects. At the end of the study 90.2% of the patients were still on IS-5-MN. In conclusion, IS-5-MN is an effective treatment for patients with chronic stable angina pectoris. It is well tolerated, with minimal side effects.

Aged↗
PubMed1990

[Results of the West German multicenter study "Urological traumatology"].

The West German Multicenter Study on Urological Traumatology ran from April 1984 to December 1986. During this time, 19 departments of urology evenly scattered over the Federal Republic of Germany including Berlin (West) recorded and evaluated the data pertaining to a total of 385 patients (83% male, 17% female) with urogenital trauma. The distribution of the different mechanisms of injury demonstrates that 41% were due to traffic accidents; 13% each to accidents during sports and work; 8% to sexual activities; and 6% to violence. The trauma was slight in 40% of the cases, moderate in 21%, and severe in 39%. Of a total of 427 urogenital injuries, 27% were combined with intra-abdominal and 24% with pelvic injuries. Renal injuries were recorded in 51%, ruptures accounting for 49% of these and contusions for 48%. Hilar lesions were observed in 7%, with complete destruction of the organ occurred in 6% of these cases. In all, 76% of these traumas were treated conservatively, while 8% each required surgical reconstruction and nephrectomy. Traumatic lesions of the urinary bladder, urethra, penis, and scrotum including the testes and accessory organs were recorded in about 10% each. Macrohematuria was seen with 73% of renal, 83% of urinary bladder, and 73% or urethral injuries. Microhematuria occurred with 24%, 9%, and 13% of all cases, while no hematuria was ascertained in 3%, 5%, and 13% of renal, bladder and urethral traumas, respectively. The injury-related sensitivity of the different imaging methods was calculated at 95% for cystograms, 91% for retrograde urethrograms, and 83% for angiograms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Evaluating magnetic resonance tomography studies of the extremities--results of a multicenter study for evaluating nuclear magnetic resonance tomography].

MR examinations of the extremities occupy the first place in whole body examinations via MR. Highest accuracy quotas in this area with an average of 93.8% were obtained for tumours, trauma and necroses of the bones. These high accuracy quotas, however, were achieved only if sufficient preliminary information was available. Other statistically significant factors were found to be the field strength, the combined use of spin echo and fast imaging sequences and the use of the multislice technique.

Bone Neoplasms↗
PubMed1992

[Phase 2 clinical study of 99mTc-ECD--a multicenter study].

A phase 2 clinical study of a newly developed brain perfusion agent, 99mTc-ECD, was performed in 166 cases of cerebrovascular diseases and impairment of brain function to evaluate effectiveness, usefulness, optimum dose and optimum timing of imaging as a multi-center study involving 10 institutions in Japan. All cases were judged as no problems on safety and any side effects due to the administration of the compound were not observed. Out of 163 cases evaluated for the clinical usefulness, valuable information for clinical diagnosis was obtained in 160 cases (98.3%), and 154 cases (94.5%) were judged as "extremely useful" or "useful". Although SPECT imaging was possible from 5 min after injection, images obtained between 60 and 90 min after injection showed relatively better image quality in many cases. Regarding standard administration dose, 400 to 800 MBq were considered to be appropriate. 99mTc-ECD is considered to be a promising radiopharmaceutical as a brain perfusion agent.

Adolescent↗