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81.
Incidence of ulnar nerve entrapment at the elbow in repetitive work   总被引:1,自引:0,他引:1  
OBJECTIVES: Despite the high frequency of work-related musculoskeletal disorders, the relation between work conditions and ulnar nerve entrapment at the elbow has not been the object of much research. In the present study, the predictive factors for such ulnar nerve entrapment were determined in a 3-year prospective survey of upper-limb work-related musculoskeletal disorders in repetitive work. METHODS: In 1993-1994 and 3 years later, 598 workers whose jobs involved repetitive work underwent an examination by their occupational health physicians and completed a self-administered questionnaire. Predictive factors associated with the onset of ulnar nerve entrapment at the elbow were studied with bivariate and multivariate analyses. RESULTS: The annual incidence was estimated at 0.8% per person-year, on the basis of 15 new cases during the 3-year period. Holding a tool in position was the only predictive biomechanical factor [odds ratio (OR) 4.1, 95% confidence interval (95% CI) 1.4-12.0]. Obesity increased the risk of ulnar nerve entrapment at the elbow (OR 4.3, 95% CI 1.2-16.2), as did the presence of medial epicondylitis, carpal tunnel syndrome, radial tunnel syndrome, and cervicobrachial neuralgia. The associations with "holding a tool in position" and obesity were unchanged when the presence of other diagnoses was taken into account. CONCLUSIONS: Despite the limitations of the study, the results suggest that the incidence of ulnar nerve entrapment at the elbow is associated with one biomechanical risk factor (holding a tool in position, repetitively), overweight, and other upper-limb work-related musculoskeletal disorders, especially medial epicondylitis and other nerve entrapment disorders (cervicobrachial neuralgia and carpal and radial tunnel syndromes).  相似文献   
82.
83.
Low molecular weight heparins (LMWHs) are used for prevention of clotting in the dialysis circuit. The aim of this trial was to define the optimal dose of a new LMWH and to test the efficiency of a single dose at the start of the session. Fifteen patients were treated according to a double blind and crossover design during 4 blocks of 5 consecutive reviparin doses assigned randomly as 50, 60, 70, 85, and 100 IU anti-Xa/kg. Assessment was carried out on screening of fibrin rings or clots in the arterial and venous air traps and on visual detection of fiber in the dialyzer after rinsing. These clinical results were compared to plasmatic anti-Xa activity and thrombin-antithrombin (TAT) complex generation. A standard dose of 70 IU anti-Xa/kg of nadroparin was used as the control. After a bolus of 50 to 100 IU anti-Xa/kg, the occurrence of fibrin rings and clots in the air traps was dependent on three factors: dose of LMWH, time of the session, and patient status. A bolus of 85 IU anti-Xa/kg of reviparin was effective and safe for sessions of 4 h. For this dose, plasmatic anti-Xa activity was 0.96 +/- 0.28 IU/ml at Hour 2 and 0.82 +/- 0.22 IU/ml at Hour 4. TAT complexes are good markers of the activation of the coagulation. They did not increase during a 4 h session after a reviparin bolus of 100 IU/kg. For the same LMWH dose, the trial shows a great variability of the clinical effect and anti-Xa activities from one patient to another. A single dose of 85 IU anti-Xa/kg of reviparin can be used at the start of the dialysis session as a loading dose. We advise adapting the dose during the subsequent sessions according to the appearance of the blood circuit. The benefit of monitoring anti-Xa activity and TAT complexes could be tested in a further trial.  相似文献   
84.
银杏叶制剂对心绞痛患者的抗氧化和抗脂质过氧化作用   总被引:15,自引:0,他引:15  
目的:探讨银杏叶制剂对心绞痛患者的抗氧化和抗脂质过氧化作用。方法:检测了78例心绞痛患者经银杏叶制剂“天宝宁”治疗前后的血浆维生素C(P-VC)、维生素E(P-VE)、β-胡萝卜素(P-β-CAR)、过氧化脂质(P-LPO)以及红细胞超氧化物歧化酶(E-SOD)、过氧化氢酶(E-CAT)、谷胱甘肽过氧化物酶(E-GSH-PX)、过氧化脂质(E-LPO)值。结果:与治疗前比较,治疗后的P-VC、P-  相似文献   
85.
BACKGROUND: Although thoracic radiotherapy is considered to be useful for the treatment of patients with small cell lung carcinoma (SCLC), its optimal administration schedule is still controversial. METHODS: In a multicenter clinical trial, 164 patients with limited SCLC (of whom 156 were eligible for the study) were randomized to receive either concurrent thoracic irradiation, initiated immediately after the second cycle of chemotherapy (Days 30-64) at a dose of 50 grays in 20 fractions, or alternating thoracic irradiation, scheduled in 3 courses between the second, third, fourth, and fifth cycles of chemotherapy with a 7-day rest period after and before chemotherapy at a dose of 20 grays in 8 fractions (Days 36-47 and Days 64-75) and then 15 grays in 6 fractions (Days 92-101). The same chemotherapy regimen (cyclophosphamide-doxorubicin or vindesine-etoposide) was administered every 4 weeks in both groups. RESULTS: Concurrent radiotherapy-induced lung toxicity led to early termination of this trial when a significant difference was observed (6 cases vs. 1, P = 0.05, 2-sided log rank test). Objective response rates were 89% in the 82 patients of the concurrent radiotherapy group and 95% in the 74 patients of the alternating radiotherapy group. Median survival periods were 13.5 and 14.0 months, respectively, with no significant difference between the two survival distributions (P = 0.15, 2-sided log rank test). Toxic deaths due to bone marrow hypoplasia were similar in both groups (3 vs. 2), but mortality due to lung toxicity (pulmonary fibrosis) was more frequent with concurrent radiotherapy (6 patients) than with alternating radiotherapy (1 patient) in long term analysis (P = 0.05, 2-sided log rank test). CONCLUSIONS: Although no statistically significant overall survival difference was observed between the two radiation therapy schedules, the better tolerance of the alternating schedule justifies the choice of this schedule with this chemotherapy regimen, although it may not be applicable to other chemotherapy regimens.  相似文献   
86.
So far there is no good evidence that chemotherapy improves survival in non small cell lung cancer. Reports of randomized trials testing chemotherapy versus supportive treatment alone are very few. In recent years, more and more emphasis has been put on the quality of life for cancer patients. Subjective tests such as Anamnestic comparative self Assessment (A.C.S.A. test, Dr. Bernheim) were designed as well as objective ones, using different types of self evaluation. However very few studies have been focused on this aspect in patients with non small cell lung cancer. Therefore the G.E.T.C.B. (Groupe d'Etude et de Traitement des Cancers Bronchiques) decided to initiate a cooperative randomized trial (02 CB 84) in metastatic epidermoid and large cell bronchus carcinoma, in order to test the potential benefit from chemotherapy in these tumors and how it affects the quality of live. In this trial, C.O.P.A.C. combination (Cyclophosphamide, Vincristine, Cis-Platinum, Adriamycin and CCNU) is randomized versus no chemotherapy. The quality of life is assessed monthly on the one hand by a modified A.C.S.A. test performed by a physician and on the other hand by a question list given to the patient. This question list attempts to evaluate the impact of disease as a reference point. Finally protocol 02 CB 84 (activated in 05/84) may give information about the effect of chemotherapy on both survival and quality of life.  相似文献   
87.
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.  相似文献   
88.
Experience with the Amplatz retrievable vena caval filter. Work in progress   总被引:1,自引:0,他引:1  
The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.  相似文献   
89.
For most diseases, one observes great variability in clinical course and response to therapy which should be taken into account in the design and the analysis of clinical trials. Eligibility criteria and stratified randomization use prognostic knowledge. A suitable analysis of randomized studies includes: (1) checking treatment effect groups for comparability, (2) adjustment of treatment effect by stratifying or modeling to account for any imbalances in prognostic factors and to increase the precision of the treatment comparison by reducing random variation, (3) looking for treatment-covariate interactions suggesting that response to treatment depends on patients' characteristics. Tests for interaction should be interpreted with caution in light of medical plausibility; multiple comparisons should be taken into account. Recording information on known prognostic factors in clinical trials is important, as is the continuing search for new ones.  相似文献   
90.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree.  相似文献   
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