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During opiate anesthesia (standardized dosage of fentanyl) for operation of cerebral aneurysms after subarachnoid hemorrhage, different hemodynamic, respiratory, metabolic, and endocrine parameters were determined before (1 in Fig. 1-4), after (6), and during consecutive stages of induced hypotension (systolic blood pressure 100 mmHg (2), 90 mmHg (3), 80 mmHg (4, 5) during an interval of 20 min), comparing two groups with different vasodilating drugs. In the first group (nimo/NNP in Figs. 2-4) a constant infusion of nimodipine was applied (1.2 micrograms/kg b.w. X min-1), while sodium nitroprusside (NNP) was added in small amounts as necessary to achieve the respective values of systolic blood pressure. In the second group (NNP in Figs. 2-4) induced hypotension was done with NNP alone (maximal dosage: 8 micrograms/kg X min-1). Each group consisted of 11 patients. Additional nimodipine (in the first group), a calcium antagonist commonly recommended for preventing vasospasm and consequent neurologic deficits after subarachnoid hemorrhage, not only reduced the need for NNP, a vasodilating drug with potential toxicity, by 70%-80% as compared to the second group (Table 1). In addition, the cardiovascular situation was more stable in patients with nimodipine infusion: rapid variations of blood pressure and heart rate as well as tachyphylaxis and rebound, typical for NNP-induced hypotension, were avoided. Nevertheless, comparing the hemodynamic data at fixed stages of hypotension, there were only minor differences between both groups (Fig. 2). Reduction of blood pressure was due to a decrease in vascular resistance and was accompanied by an increase in cardiac output.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The cephalogram is the standard used by orthodontists to assess skeletal, dental, and soft tissue relationships. This approach, however, is based on 2-dimensional (2D) views used to analyze 3-dimensional (3D) objects. The purpose of this project was to evaluate and compare a 3D imaging system and traditional 2D cephalometry for accuracy in recording the anatomical truth as defined by physical measurements with a calibrated caliper. Thirteen skeletal landmarks were located by both radiographic methods on 9 dry human skulls. Intraclass correlation (0.995), variance (0.054 mm(2)), and standard deviation (SD) (0.237 mm) were averaged over 76 measurements and derived from precision calipers to establish these physical measurements as a reliable gold standard to make comparisons of the 2D and 3D radiographic methods. The results showed great variability of the 2D from the gold standard, with the range varying from -17.68 mm (underestimation of Gn-Zyg R) to +15.52 mm (overestimation of Zyg L-Zyg R). In contrast, the 3D method (Sculptor, Glendora, Calif) indicated a range of the SD from -3.99 (underestimation) mm to +2.96 mm (overestimation). The 3D evaluation was much more precise, within approximately 1 mm of the gold standard. These results indicate that, when the actual distance is measured on a human skull in its true dimensions of 3D space, the Sculptor program, by using a 3D method, is more precise and 4 to 5 times more accurate than the 2D approach. Evaluating distances in 3D space with a 2D image grossly exaggerates the true measure and offers a distorted view of craniofacial growth. There is an inherent problem of representing a linear measure occupying a 3D space with a 2D image.  相似文献   
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Patients with imported highly contagious diseases like viral hemorrhagic fever (VHF), pneumonic plague or anthrax require special preventive measures and strict isolation. In addition, new emerging infections like severe acute respiratory syndrome (SARS) and epidemic influenza also have to be taken into account. At present five high security infectious disease units for patient care are available in Germany. Due to the relatively nonspecific symptoms, a patient with one of these infections may also be admitted to any other hospital. Therefore each hospital should develop a concept for the management and control of these lifethreatening highly contagious diseases. The present article describes the current emergency plan developed for the management of patients with highly contagious diseases at Hannover Medical School.  相似文献   
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The objective of this study was to develop and verify a new technique for monitoring the progression of osteoarthritis (OA) by combining a rat model with the imaging modality optical coherence tomography (OCT). Time-sequential, in vivo, OCT imaging was performed on the left femoral condyles of 12 Wistar rats following sodium-iodoacetic acid-induced OA progression. The right femoral condyles (untreated) were also imaged and served as controls. Imaging was performed on days 0, 10, 20, 30, and 60 with an OCT system capable of acquiring images at four frames per second and an axial resolution of 5 microm. Progressive changes were analyzed using an OA scoring system. OCT successfully identified progressive cartilage degeneration as well as alteration of the cartilage/bone interface. Significant changes to both of these structures were observed in the sodium-iodoacetic acid-injected condyles. Structural changes detected with OCT were confirmed histologically. OCT in combination with a well-known model used in arthritis research represents a powerful tool for following degenerative joint disease progression in a given animal by detecting changes to the cartilage/bone interface and articular cartilage.  相似文献   
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Penile plethysmography was used to examine sexual preferences of individuals accused of child molestation in the course of custody conflicts. Information regarding the alleged offenders, victims, and sex offense was gathered. In comparison to accused offenders who are not engaged in custody disputes, the subjects were more often accused of sexually abusing a younger child who was a biological relative. The source of accusations was usually the mother. Additionally, the custody-dispute subjects were less likely to have a prior criminal history. Penile tumescence data suggested that the subjects involved in custody disputes were less sexually aroused by children than those subjects who were not involved in custody conflicts. However, the results revealed that in both groups a substantial number of subjects responded equally or more to the child stimuli. In sum, the alleged offenders involved in custody disputes appeared less deviant on several measures.  相似文献   
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