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31.

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   
32.
In this paper morphological and physiological experiments are described that refer to the concept of neurogenic inflammation of meningeal structures as a putative source of migrainous pain and other headaches. The main emphasis of this study carried out on the duramater encephali of the rat was the functional role of calcitonin generelated peptide (CGRP), a vasodilatory neuropeptide of fine afferent nerve fibres. Immunocytochemical preparations showed that the parietal dura mater was densely innervated by CGRP immunoreactive nerve fibres, the distribution and ultrastructure of which were examined by ligh and electron microscopy. The dense innervation around the medial meningeal artery suggested a vasomotor function of these peptidergic fibres. In further experiments the CGRP immune product of the nerve fibres could be diminished by electrical stimulation of the dura mater. Extracellular recordings from trigeminal ganglion cells showed that electrical and mechanical stimulation of large dural vessels activate trigeminal afferents. In a final series of experiments the dural blood flow around branches of the medial meningeal artery was measured with a laser Doppler flowmeter. The blood flow was increased by electrical stimulation of the dura, the size of this effect depending on stimulus strength and frequency. This increase was inhibited in a dose-dependent manner by the competitive CGRP antagonist CGRP(8-37), which shows an involvement of CGRP in the regulation of meningeal blood flow. We conclude that stimulation of trigeminal afferents innervating the dura mater releases CGRP from peptidergic afferent terminals, thereby causing vasodilatation and increasing the meningeal blood flow, an important component of neurogenic inflammation. The preparation decribed will be used for further studies on basic mechanisms of neurogenic inflammation and nociception in meningeal structures.  相似文献   
33.
 The expression of the pyruvate kinase (PK) isoenzymes L and M2 was analysed in the livers of rats treated with the hepatocarcinogenic agent N-nitrosomorpholine (NNM) in the drinking water. In control animals L-PK expression was restricted to liver parenchymal cells, whereas M2-PK was detected in bile duct epithelial, blood vessel wall, endothelial and Kupffer cells. In rats treated with NNM proliferating oval cells were consistently L-PK negative and M2-PK positive, while the ductal cells of cholangiofibroses were clearly L-PK positive and coexpressed M2-PK. However, no morphological differentiation of ductal cells into hepatocyte-like cells was observed. In the clear and acidophilic cell foci storing glycogen in excess strong staining for L-PK was observed. In glycogen-poor foci induced by NNM a shift from L-PK to M2-PK expression takes place. Received: 24 March 1998 / Accepted: 13 November 1998  相似文献   
34.
Forty-nine patients (mean age, 54 years) admitted for displaced ankle fractures were observed retrospectively to determine by clinical examination and measurement of plantar pressure distribution whether successful surgical treatment of ankle fractures had led to gait symmetry. The mean followup was 36 months (range, 19-54 months). The deviation in gait was quantified using peak pressure. Using a clinical score, most of the patients had satisfactory results. The plantar pressure distribution showed significant load asymmetries of patients with satisfactory results and those with non-satisfactory results. Dynamic gait analysis allows quantification of gait asymmetry and clinically non-visible gait disorder.  相似文献   
35.
Radioiodine labelled 17-iodo-heptadecanoic acid (IHA) is used for non-invasive study of myocardial metabolism in coronary heart disease and cardiomyopathy. Yet in the interpretation of in vivo myocardial tracer kinetics, it is controversial whether the intracellular degradation of IHA or the removal of iodide across cellular membranes is the rate-limiting step in iodide release from the myocardium. In five patients undergoing coronary sinus catheterization, a mixture of about 40 kBq of [123I] NaI was injected into the left coronary artery. During the following 15-min period, frequent blood samples were taken from the aorta and the coronary sinus. In the aqueous phase of the venous blood, 14CO2 and inorganic 131I appeared nearly in parallel, with a peak time of 4–5 min. Moreover, as shown by the AV difference, there was no significant back diffusion of IHA and no significant non-specific deiodination detectable over the period of observation. There was myocardial retention of inorganic iodide (123I) injected into the left coronary artery. The data strongly support the premise that lipid turnover through -oxidation is the rate-limiting step in the externally measured release of iodide after IHA injection, provided that recirculating inorganic radioactive iodide is corrected for. In addition, 15 volunteers were studied using [11C]palmitic acid and [123I]IHA using PET and dynamic planar camera scintigraphy with iodide correction. There was no significant difference between the mean values of the elimination half-times, and also no significant correlation between half-times of both fatty acids for single individuals.  相似文献   
36.
For the early detection of prostate cancer, a patient should undergo digital rectal examination (DRE) and PSA investigation. Follow-up of increased PSA levels detects nearly 80% of cancers. Positive predictive value of suspicious DRE and PSA is about 50%. Whereas in the first evaluation of this case-finding trial about 70% of the patients had organ-confined cancers, nearly all of the detected cancers in the follow-up investigation were organ confined. The increased number of organ-confined cancers detected in early periodical examinations can lead to a reduction of mortality and morbidity from prostate cancer.  相似文献   
37.
We observed an association between rotavirus diarrhoea and hypocalcaemia in several patients and therefore started a prospective evaluation with measurement of calcium levels in all patients with rotavirus infection during a period of 8 months. We report on 54 infants with rotavirus gastro-enteritis. Serum concentrations of sodium, potassium, and total and ionized calcium were measured on admission. If hypocalcaemia was detected, total and ionized calcium were measured every day until recovery. Calcium was supplemented as calcium gluconate which was added to milk. Out of 54 newborns with rotavirus gastro-enteritis, 20 developed hypocalcaemia. All these newborns had severe diarrhoea. Seven infants were admitted because of convulsions, but EEG and ultrasonographic examination of the brain revealed no abnormalities. Once the infants' clinical condition and the consistency and frequency of the stool had improved, calcium concentrations increased and remained within the reference range without supplementation. Conclusion Rotavirus gastro-enteritis seems to be a cause of neonatal hypocalcaemia. Received: 26 June 1997 and in revised form: 20 December 1997 / Accepted: 26 December 1997  相似文献   
38.
Germinale Hodenmalignome werden ausnahmslos in fakultativ-kurativer Intention behandelt. Bei Frühstadien werden mit multimodalen Therapiekonzepten exzellente Ergebnisse erreicht, dabei weisen testikul?re Seminome Heilungsraten von nahe 100% auf. Diese sind beispielgebend für interdisziplin?re stadiengerechte onkologische Behandlungen solider Organtumoren. Solche Erfolge begründen Bemühungen, die Therapie ohne Kompromittierung erreichter Heilungsraten weiter zu reduzieren und dabei therapiebedingte Einschr?nkungen an Lebensqualit?t für die Patienten und hierfür aufzuwendende sozio?konomische Kosten so gering wie m?glich zu halten. Erforderlich sind solche Bemühungen vor dem Hintergrund steigender Inzidenzraten und alternativer Behandlungsmodalit?ten. Ihre klinische Relevanz ergibt sich aus dem hohen Anteil in Frühstadien diagnostizierter Erkrankungsf?lle. Bei identischer diagnostischer Strategie für alle testikul?ren Keimzellmalignome ist für die postoperativen Behandlungsoptionen bei frühen Stadien zwischen den radiosensiblen Seminomen und den Nicht-Seminomen zu unterscheiden. Für die Seminome werden in dieser Arbeit, orientiert am jeweiligen Tumorstadium, die perkutane Strahlentherapie nach Orchiektomie als Standardtherapie erl?utert und deren Alternativen im Stadium cS I, systemische Carboplatin-Monozytostase oder Surveillance-Strategie, bzw. im Stadium cS IIA/B, systemische Chemotherapie, vergleichend dargestellt.  相似文献   
39.
Dr. G. Heß 《Der Onkologe》2005,11(5):571-577
Zusammenfassung Auch wenn in den vergangenen Jahren z. T. eine Verbesserung der Prognose von Non-Hodgkin-Lymphomen (NHL) bereits mit veränderten konventionellen und eskalierten Chemotherapieverfahren indolenter und aggressiver Lymphome erreicht werden konnte, verläuft für einen großen Teil der Patienten die Tumorerkrankung noch immer fatal. Da eine weitere Optimierung konventioneller Modalitäten schwer möglich erschien, stellte die Etablierung immuntherapeutischer Ansätze eine attraktive Option dar. Die erfolgreiche Einführung monoklonaler Antikörper in die Behandlung maligner Lymphome hat die Immuntherapie fest etabliert. Weiterentwicklungen dieses passiven Immuntherapieansatzes sind auf dem Weg in den klinischen Alltag. Daneben sind unterschiedliche Verfahren aktiver Immunisierung (Vakzinierung) in präklinischen und frühen klinischen Entwicklungen, deren Etablierung eine weitere Bereicherung des therapeutischen Armentariums darstellen kann. Zuletzt hat — insbesondere für Hochrisikopatienten — die allogene Stammzelltransplantation in der jüngsten Vergangenheit an Attraktivität gewonnen.  相似文献   
40.
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