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101.
The effects of cationized serum albumin on the resorptive response to PTH and other agents were examined in organ cultures of fetal rat long bones. Human serum albumin (HSA) was cationized to an isoelectric point greater than 9.5 by addition of hexamethylene diamine. When cationized albumin (C-HSA) replaced HSA or BSA in the medium, resorption could be stimulated by 10- to 30-fold lower concentrations of synthetic (1-34) human or bovine PTH or intact 1-84 bovine PTH. Using C-HSA, significant resorption was obtained in some experiments with the concentration of PTH as low as 25 pM, but in most experiments 100 pM-400 pM concentrations were required. In contrast, 6.25 nM 1-34 PTH was required for a response in HSA. The sensitivity to stimulation of resorption by 1,25-dihydroxy-vitamin D and prostaglandin E2 was not increased. Hence, the increased sensitivity to PTH is most likely due to a selective protective effect of C-HSA, which might decrease nonspecific binding or degradation of the hormone. 相似文献
102.
The effect of Rowachol (200 mg tid), an essential oil preparation, on biliary lipid secretion and serum lipids was measured in six healthy male volunteers before and after four weeks of treatment. Biliary cholesterol and phospholipid secretion increased significantly from 113 +/- 36 (SD) mumol/h to 155 +/- 52 mumol/h (p less than 0.05) and from 409 +/- 145 mumol/h to 587 +/- 185 mumol/h (p less than 0.05), respectively. Bile acid secretion increased from 1519 +/- 662 mumol/h to 2287 +/- 1175 mumol/h (p greater than 0.05 and greater than 0.10). This marked increase in biliary lipid secretion was not followed by a change in molar composition of biliary lipids and lithogenicity of bile. Serum cholesterol and triglycerides declined from 4.9 mmol/l to 4.1 mmol/l (p less than 0.05) and from 1.2 mmol/l to 0.9 mmol/l (p less than 0.05) respectively. The ratio of high-density-lipoprotein cholesterol to total cholesterol increased from 0.22 to 0.31 (p less than 0.05). Although it has been shown previously that Rowachol could dissolve cholesterol gall stones the present results indicate that Rowachol alone has only weak litholytic properties, at least in normal volunteers, but might have several advantages when combined with chenodeoxycholic or ursodeoxycholic acid. 相似文献
103.
Martin Stacho Sara Letzner Carsten Theiss Martina Manns Onur Güntürkün 《The Journal of comparative neurology》2016,524(14):2886-2913
Previous studies have demonstrated that the optic tecta of the left and right brain halves reciprocally inhibit each other in birds. In mammals, the superior colliculus receives inhibitory γ‐aminobutyric acid (GABA)ergic input from the basal ganglia via both the ipsilateral and the contralateral substantia nigra pars reticulata (SNr). This contralateral SNr projection is important in intertectal inhibition. Because the basal ganglia are evolutionarily conserved, the tectal projections of the SNr may show a similar pattern in birds. Therefore, the SNr could be a relay station in an indirect tecto–tectal pathway constituting the neuronal substrate for the tecto–tectal inhibition. To test this hypothesis, we performed bilateral anterograde and retrograde tectal tracing combined with GABA immunohistochemistry in pigeons. Suprisingly, the SNr has only ipsilateral projections to the optic tectum, and these are non‐GABAergic. Inhibitory GABAergic input to the contralateral optic tectum arises instead from a nearby tegmental region that receives input from the ipsilateral optic tectum. Thus, a disynaptic pathway exists that possibly constitutes the anatomical substrate for the inhibitory tecto–tectal interaction. This pathway likely plays an important role in attentional switches between the laterally placed eyes of birds. J. Comp. Neurol. 524:2886–2913, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
104.
Nir N. Somekh Maurice Rachko Gregg Husk Patricia Friedmann Steven R. Bergmann 《Journal of nuclear cardiology》2008,15(2):186-192
Background Chest pain is one of the most common complaints of patients presenting at emergency departments. However, the most appropriate
diagnostic evaluation for patients with chest pain but without acute coronary syndrome remains controversial, and differs
greatly among institutions and physicians. At our institution, patients with chest pain can be admitted to an internist-run
hospitalist service, a private attending service, or a cardiologist-run Chest Pain Unit. The goal of the present study was
to compare the management and outcomes of patients admitted with chest pain based on admitting service.
Methods The charts of 750 patients (250 consecutive patients per service) with a discharge diagnosis of chest pain were studied retrospectively.
Results Patients admitted to the Chest Pain Unit were younger and had a lower prevalence of known coronary artery disease, hypertension,
or diabetes, but a similar prevalence of other risk factors compared with the other groups. Sixty percent of the patients
in the Chest Pain Unit underwent stress myocardial perfusion imaging as their primary diagnostic modality (vs 22% and 12%
of patients in the hospitalist and private services, respectively; P<.001). In contrast, 35% of the patients admitted to the hospitalist service underwent rest echocardiography (vs 8% and 17%
of patients in the Chest Pain Unit and private services, respectively; P<.001). Finally, 47% of the patients in the private service underwent coronary angiography as their primary diagnostic modality
(vs 6% and 10% of patients in the Chest Pain Unit and hospitalist services, respectively; P<.001). The length of stay was shortest for patients in the Chest Pain Unit (1.4±1.2 days vs 3.9±3.4 days and 3.5±3.6 days
in the hospitalist and private services, respectively; P<.001), even when corrected for patient age and number of risk factors. Readmission within 6 months was lowest for patients
in the Chest Pain Unit (4.4% vs 17.6% and 15.2% in the hospitalist and private services, respectively; P<.001).
Conclusions The results of this study demonstrate that a highly protocolized chest pain unit, using myocardial perfusion imaging as primary
diagnostic modality, results in a decreased length of stay and readmission rate. 相似文献
105.
Vertebral autograft used as bone transplant for anterior cervical corpectomy: technical note 总被引:13,自引:0,他引:13
OBJECTIVE: In this prospective patient study, we used a surgical technique for autograft bone fusion during anterior cervical corpectomy (ACC) in patients experiencing cervical spondylotic myelopathy. We packed the resected bone material of the corpectomy into a titanium mesh cage. To evaluate the efficacy of our autograft technique, we analyzed the results according to neurological outcome, radiological outcome, and complications. METHODS: Between 1995 and 1998, 27 ACC operations were performed for cervical spondylotic myelopathy caused by multisegmental cervical spondylosis. In all patients, decompression of the cervical canal and/or spinal nerve roots was performed by a median cervical corpectomy by an anterior approach. After the ACC was completed, a titanium mesh cage, which was variable in diameter and length, was filled with morselized and impacted bone material from the cervical corpectomy and was then implanted. An anterior cervical plate was placed in all patients to achieve primary stability of the cervical vertebral column. Age, sex, pre- and postoperative myelopathy, number of decompressed levels, radiological results, and complications were assessed. The severity of myelopathy was graded according to the scoring system of the Japanese Orthopaedic Association. RESULTS: Symptomatic improvement of neurological deficits was achieved in 80% of the patients. The mean preoperative Japanese Orthopaedic Association score improved from 13.1 to 15.2 postoperatively (P < 0.05). No patient demonstrated worsening of myelopathic symptoms. Radiological follow-up studies demonstrated complete bony fusion in all patients. A vertical movement of 2.25 +/- 0.43 mm of the titanium cage into the adjacent vertebral bodies was observed in 24 patients. In patients with either a lordotic or neutral cervical spinal axis postoperatively, the axis remained unchanged during the entire follow-up period. CONCLUSION: The results of this study demonstrate that transplantation of autograft bone material harvested during the ACC integrated well in the cage and in the adjacent vertebral bodies. Thus, complications associated with explantation of autograft material from other donor sites, e.g., the iliac crest, could be avoided. The early postoperative and midterm follow-up periods provided no evidence of morphological or functional instability of the operated cervical segments when this autograft technique was used in combination with cervical instrumentation. 相似文献
106.
Training for advanced laparoscopic surgery. 总被引:2,自引:0,他引:2
OBJECTIVE: To evaluate the efficiency of training for advanced minimally-invasive surgery in rats. SETTING: Teaching hospital, Germany. SUBJECTS: 10 surgical residents with few laparoscopic training skills had two days laparoscopic microsurgical training using rats. INTERVENTIONS: Increasingly difficult procedures started using a rubber model, followed by 'open' and 'closed' rat models simulating laparoscopic conditions. MAIN OUTCOME MEASURES: The surgical skills of all participants were assessed before and after the laparoscopic training course by applying 5 defined tasks in a simulation trainer. As a control group, 8 surgical residents with the same amount of minimal-invasive training were tested after a 2-day interval. RESULTS: All participants of the laparoscopic training programme significantly improved their surgical skills for all 5 tasks (p < 0.05). In the control group only one of the 5 tasks was significantly improved after repetition. Participants of the complete training programme consistently improved their surgical skills significantly compared with the controls before and after repetition (p < 0.05). CONCLUSION: Surgical training in minimal-invasive techniques in the rat model is effective and reproducible especially to improve laparoscopic skills such as bimanual tissue handling, knot tying and microsurgical suturing. 相似文献
107.
Robert K. Zahn Sarah Grotjohann Heiko Ramm Stefan Zachow Michael Putzier Carsten Perka Stephan Tohtz 《International orthopaedics》2016,40(8):1571-1575
Purpose
Pelvic tilt determines functional orientation of the acetabulum. In this study, we investigated the interaction of pelvic tilt and functional acetabular anteversion (AA) in supine position.Methods
Pelvic tilt and AA of 138 individuals were measured by computed tomography (CT). AA was calculated in relation to the anterior pelvic plane (APP) and relative to the table plane. We analysed these parameters for gender-specific and age-related differences.Results
The mean pelvic tilt was -0.1?±?5.5°. Pelvic sagittal rotation displayed no gender nor age related differences. Females showed higher angles of AA compared with males (20.0° vs 17.2°, p?<?0.001; AA relative to the APP). Anterior tilting of the pelvis positively correlated with AA and individuals with high AA had a higher anterior pelvic tilt compared with those with low AA (p?<?0.0001; AA relative to the APP).Conclusions
AA has to be calculated regarding pelvic sagittal rotation for correct acetabular orientation. Pelvic tilt is dependent on acetabular orientation and compensates for increased AA.108.
Tobias Hüppe Sascha Kreuer Hinnerk Wulf Dennik Freitag Martin Seidel Tobias Teucke Felix Maurer Andreas Kirschbaum Tilo Koch Frank Langer Thomas Volk Carsten Feldmann 《Acta anaesthesiologica Scandinavica》2023,67(4):455-461
Background
Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.Methods
In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.Results
In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.Conclusion
During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.Registration of Clinical Trial
DRKS-ID DRKS00014788 ( www.drks.de ). 相似文献109.
Configuration of the interdisciplinary emergency unit within the university clinic of G?ttingen was successfully reorganized during the past two years. All emergencies except traumatologic, gynecologic and pediatric emergencies are treated within this functional unit which is guided by the center of internal medicine. It is organized in a three shift operation manner over a period of 24 hours. Due to a close interdisciplinary collaboration between different departments patients receive optimal diagnostic and therapeutic treatment within a short period of time. To improve processes within the emergency department a series of measures were taken including the -establishment of an intermediate care unit for unstable patients, setting up of special diagnostic and therapeutic units for the acute coronary syndrome as well as stroke, implementation of standardized clinical pathways, establishment of an electronic data processing network in close communication with all diagnostic entities, introduction of a quality assurance system and reduction of medical costs. Reorganization measures lead to a substantial optimization and acceleration of emergency proceedings and thus, provides optimal patient care around the clock. In addition, medical costs could clearly be reduced at the interface between preclinical and clinical emergency medicine. 相似文献