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41.
Journal of Immigrant and Minority Health - Up until recently incidences of tuberculosis (TB) had been declining for many years in Germany. The rise in TB cases coincided with a large increase in...  相似文献   
42.

Methods

After approval by the local Ethics Commitee and after informed consent had been given, 40 patients scheduled for elective maxillofacial surgery were included in this double-blind, randomized study. As a supplement to standardized general anaesthesia (isoflurane, N2O), the patients received either clonidine 5 μg/kg or placebo during the last hour of the operation. Blood pressure, heart rate, time of recovery, and sedation and pain scores were measured postoperatively. The occurrence of nausea, vomiting or shivering was noted, as were the requirements of piritramide for analgesia, which was administered on demand in titrating dosages, and of nifedipine for systolic blood pressure exceeding 180 mm Hg.

Results

The two groups were comparable regarding biometric parameters, ASA-classification and duration of anaesthesia. Clonidinetreated patients were later in opening their eyes (22.5±11.9 min vs 17.9±10.9; n.s.) and the ability to state their dates of birth returned later (32.2±11.6 min vs. 25.7±12.8;P<0.05). Pain was more frequent in the placebo group (P<0.05 after 30 min), and there-fore, these patients required much more piritramid (P<0.01). The sedation scores showed no significant differences. No vomiting occurred in the clonidine group, and shivering was less frequent (P<0.01). The placebo group received more nifedipine (P<0.05) because the rate-pressure product was higher (P<0.01).

Discussion

Opiates are frequently used as analgesics after maxillofacial surgery, even though their most common side effect—respiratory depression, nausea and vomiting—are particularly dangerous in these patients because of the obstruction of the upper respiratory tract. Self-titration of the opiate dosage on demand can decrease the incidence of serious side effects. Clonidine administered intraoperatively caused a profound reduction in analgesic requirements in this study. Additional opiate administration in the postoperative period was unnecessary in nearly all clonidine-treated patients. The attenuating effect on sympathoadrenergic reactions leads to lowering of the rate-pressure product and may be of advantage for patients suffering from arterial hypertension, angina pectoris or bronchial asthma. The slower emergence from anaesthesia following clonidine administration is probably caused by double-blind study properties preventing full consideration of the decreased isoflurane requirements after clonidine.  相似文献   
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Differentiation of the non-dividing trypomastigote form of Trypanosoma cruzi, the causative agent of Chagas disease, to the dividing amastigote form normally occurs in cytoplasm of infected cells. Here we show that calyculin A. a potent inhibitor of protein phosphatases 1 and 2A, induces at pH 7.5 extracellular transformation of long slender trypomastigotes to round amastigote-like forms which acquire characteristic features observed after the normal differentiation process: repositioning and structural changes of the kinetoplast, release of surface neuraminidase, and expression of amastigote-specific epitopes. Calyculin A inhibits parasite phosphatases and changes in the phosphorylation of specific proteins occur during the transformation process. As an exposure of trypomastigotes to calyculin A concentrations as low as 1 nM and for only 1-2 h is sufficient to induce transformation, the inhibition of calyculin A-sensitive phosphatase(s) appears to play a major role in initiating the trypomastigote differentiation.  相似文献   
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Hirayama’s disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings in nine patients with Hirayama’s disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls. In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement of the anteroposterior spinal cord diameter in each vertebral segment (C4–C7) revealed no significant differences in the degree of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama’s disease is an intrinsic motor neuron disease. Received: 15 March 1999 Received in revised form: 25 May 1999 Accepted: 1 June 1999  相似文献   
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PURPOSE: We describe the clinical and pathological features of prostate cancer diagnosed through serum prostate specific antigen (PSA), digital rectal examination and transrectal ultrasonography in a population based randomized screening study. MATERIALS AND METHODS: Between November 1993 and June 1997, 20,632 volunteers 55 to 76 years old were included in the study. In the screening arm 9,776 men underwent digital rectal examination, transrectal ultrasound and serum PSA determination. Biopsies were taken if the digital rectal examination and/or transrectal ultrasound findings were abnormal or if PSA was 4 ng/ml or greater. A total of 2,262 men underwent biopsy and 474 cases of prostate cancer were diagnosed. RESULTS: The pretreatment data were complete in 459 men, of whom 78% had clinically organ confined disease. Bone or lymph node metastases were seen in 8 cases (1.7%). Of 172 men who underwent radical prostatectomy 2 had lymph node metastases. Overall 66.3% of men treated with radical prostatectomy had organ confined disease. CONCLUSIONS: Comparison of the characteristics of prostate cancer detected through screening of the general population with those in a population based cohort of men in which there was no organized screening revealed stage reduction, primarily with regard to number of metastatic cases. Whether this stage reduction will lead to a decrease in disease specific mortality remains unknown until the study is completed and the end point of prostate cancer specific mortality is evaluated.  相似文献   
50.
OBJECTIVE: The authors present demographic and surgical data from a randomized phase III trial, instituted by the EORTC Genitourinary Group in 1988, the aim of which was to assess whether complete lymph node dissection in conjunction with radical nephrectomy for renal cell cancer is more effective than radical nephrectomy alone. METHODS: Before surgery, the renal cell carcinoma was staged and judged to be nonmetastatic and resectable. The patients were randomized prior to surgery into those having radical nephrectomy combined with complete lymph node dissection or into those having radical nephrectomy alone. Postoperatively all patients were followed until progression of disease or death. RESULTS: Of the 772 randomized patients, 41 were not eligible. 383 had a complete lymph node dissection together with a radical nephrectomy. 389 had a radical nephrectomy alone. The complication rate did not differ significantly between the two groups. A complete lymph node dissection in 336 patients revealed absence of lymph node metastases in 325 of them. CONCLUSIONS: The present study shows that complete lymph node dissection does not add morbidity to the radical nephrectomy. After proper preoperative staging, the incidence of unsuspected lymph node metastases is low (3.3%).  相似文献   
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