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111.
Summary The application of the rectal temperature time of death nomogram at the scene of death by 11 authors from 6 lego-medical institutes resulted in a standard deviation of the differences between nomographic and real death time of ± 1.3 h in 46 cases (group I) with met requirements and clearly defined points of contact, nevertheless, including 9 cases with a more progressive cooling (0.5 > Q 0.2). In cases with a real death time of more than 4 h (N = 26) the standard deviation was ± 1.0 hours corresponding to permissible variation of 95% of ± 2.0 hours. Consequently, the permissible variation of 95% was much smaller than that suggested by the nomogram. The nomographic death time interval did not agree with the real one in 5 cases out of additional 30 cases with recognizably unsure points of contact (group II).  相似文献   
112.
Summary In order to evaluate the time course of its effects, dimetindene maleate has been investigated in a histamine provocation model in man. Eight healthy male volunteers were treated i. v. with 4 mg dimetindene maleate or sodium chloride solution in a double blind, cross over study. Intracutaneous histamine injections were given at –1, 2, 5, 14, 17, 20, 23, 26, and 29 h following drug administration and the areas of flares and wheals were measured after 5, 10, 20, and 30 min. There was strong inhibition of the development both of flares and wheals, which was more pronounced for the former. Baseline adjusted areas under the curve differed significantly following drug and placebo treatment. The maximum effect was observed at 2 h.The mean residence time of the inhibitory effect was calculated to be 13 h compared to the mean residence time of dimetindene in blood of 5 h, which indicates a non-linear relationship between blood level and effect.  相似文献   
113.
Two new prenylflavonol glycosides epimedokoreanoside I ( 7) and epimedokoreanoside II ( 8) were isolated from EPIMEDIUM KOREANUM Nakai (Berberidaceae) beside five other known prenylflavonol glycosides with hypotensive activity. The structures were elucidated by spectroscopic and chemical methods.  相似文献   
114.

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   
115.
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   
116.
Background: In transscleral photocoagulation, the desired effect is coagulation of parts of the ciliary body or of the peripheral retina. However, the application is often limited by the unwanted effect of coagulation of the sclera. to reduce this effect, the ratio of incident radiation flux to radiation flux transported through the sclera (and able to coagulate the target tissue) should be minimized by the incident beam characteristics.Methods: Monte Carlo simulations for the radiation transport problem of multiple scattering in the sclera were used to calculate the ratio of transported to incident radiation for different parameter settings of beam diameters, optical thicknesses of the sclera and beam angles. To verify the theoretical calculations, an simple optical device utilizing a bulb instead of a laser source was constructed and applied to enucleated porcine eyes.Results: The theoretical calculations showed that the ratio of incident to transported radiation flux can typically be decreased by a factor of three by increasing the beam radius from 0.35 mm (as used in state-of-the-art laser devices) to 2 mm. This was confirmed by the experiments. Coagulations of the ciliary body or of the peripheral retina were possible with power densities an order of magnitude below the values normally applied with laser sources.Conclusion: To improve transscleral photocoagulation, beam diameters should be increased.  相似文献   
117.
The effects of bivalent lead on ion channels activated by kainate and -amino-3-hydroxy-5-methyl-4-isoxazolpropionate (AMPA) were studied using Xenopus oocytes microinjected with mRNA from rat brain. Lead reduced kainate-induced membrane currents in a reversible and dose-dependent manner, without affecting membrane currents induced by AMPA. Lead decreased the kainate currents with a concentration of 0.1 mol/l to 0.93 ± 0.01 and with a concentration of 100 mol/l to 0.41 ± 0.04 of the control values. The blocking effect of lead on kainate responses was voltage dependent. The inhibition was strongest at - 90 mV to - 70 mV and became weaker at more positive membrane potentials. The effect of lead on the kainate-induced membrane currents remained unchanged when the concentration of kainate was increased. Hence lead probably represents a noncompetitive channel-blocking agent for non-N-methyl-d-aspartate (NMDA) receptor channels activated by kainate.  相似文献   
118.
 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   
119.
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   
120.
Background: Hypopyon-uveitis has been identified as a dosage-dependent side effect in patients with acquired immunodeficiency syndrome who are treated for Mycobacterium avium complex (MAC) infection with systemic rifabutin. Patients and methods: We report a 38-year-old female AIDS patient with bilateral hypopyon uveitis under therapy with rifabutin in combination with clarithromycin and indinavir. Results: At the time of presentation of the bilateral hypopyon uveitis the patient was treated with rifabutin (300 mg/day), clarithromycin (1000 mg/day) and ethambutol (1000 mg/day) for an M. avium complex infection. Also, the patient received the protease inhibitor indinavir. The rifabutin dose was reduced to 150 mg/day. Hypopyon and inflammation resolved under therapy with steroids. Conclusions: The concomitant use of rifabutin, clarithromycin, and protease inhibitors may lead to hypopyon uveitis. Reduction of dosage of rifabutin (150 mg/day) and treatment with topical steroids are required.   相似文献   
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