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31.
Zusammenfassung Das Wachstumsverhalten zweier in das Gehirn von Goldhamstern implantierter menschlicher Tumoren (H. Ad. Nr. 1 und H. S. Nr. 1) wurde untersucht. Bei allen Tieren konnte ein Tumorwachstum histologisch nachgewiesen werden. Cortisonvorbehandlung der Wirtstiere begünstigte bei H. Ad. Nr. 1 die Tumorausbreitung und führte frühzeitiger zum Tode. Das intracerebrale Tumorwachstum führte jedoch auch unabhängig von der Wirtsvorbehandlung bei allen Tieren zum Tode innerhalb von 4 Wochen nach der Transplantation. Beide Geschwulst-typen wuchsen am besten in den liquorhaltigen Räumen, weniger in der Hirnsubstanz. Die Bevorzugung der Meningen durch beide Tumortypen entspricht der allgemeinen Erfahrung über die cerebrale Metastasierung entdifferenzierte Sarkome und Adenocarcinome.
Summary The growth behavior of two human tumors (H. Ad. No. 1 and H. S. No. 1) transplanted to the hamster brain has been studied. Tumor growth could be histologically verified in all animals inoculated. Cortisone-conditioning of the host increased tumor expansion and resulted in an earlier and more rapid death rate in the H. Ad. No. 1 group. Regardless of tumor or host-conditioning employed, all animals succumbed to intracerebral tumor growth by the end of the fourth week post transplantation. Both tumor types grew better in the ventricles and subarachnoid space than in the brain tissue itself. The predilection of these two tumor types for the meninges confirms our clinical knowledge on the pattern of cerebral metastasis of dedifferentiated sarcomas and adenocarcinomas.


Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   
32.
Ohne Zusammenfassung Im Auszug vorgetragen von Dr. R. Kraus am IX. internat. Congresse für Hygiene und Demographie (Madrid April 1898).  相似文献   
33.
BACKGROUND: Intraoperative ultrasound is widely used in liver surgery, but primarily for diagnostic purposes. We have developed and evaluated a system for navigated liver resections using on intraoperatively acquired 3-dimensional (3D) ultrasound data. METHODS: Navigation technique based on 3D ultrasound and an optical tracking system. Accuracy of the system was validated experimentally in a tumor model. Subsequently, clinical application was evaluated in 54 patients for resection of central liver tumors. Clinical feasibility and accuracy of the navigation technique were assessed with respect to practicability, adequacy of visualization, and precision of navigated resection (free margin). RESULTS: Evaluation of the system in the tumor model showed a significant increase of the accuracy of navigated resections compared with conventional resection (P < 0.05). Clinical application of 3D ultrasound-based navigation was feasible in 52 of 54 patients. Sufficient visualization was obtained with 2 orthogonal section planes. This navigation strategy provided complete anatomic orientation and accurate position control of surgical instruments. Mean histologic resection margin was 9 mm with a maximum deviation of 8 mm from the planned virtual resection margins. CONCLUSIONS: Optoelectronic navigation with section mode visualization in 2 orthogonal planes does sufficiently display intraoperative 3D data and enables accurate ultrasound-based navigation of liver resections.  相似文献   
34.
Abstract

Background

Golimumab (GLM) has shown its efficacy and safety in various clinical trials. We aimed to assess the effect of GLM on socio economic and health economic parameters in daily clinical practice.  相似文献   
35.
The committee was charged with determining whether healing of erosions in rheumatoid arthritis (RA) occurs. Two exercises were performed: The first asked the committee members, as a panel of experts, to express agreement or disagreement with the presence of improvement and features of bone reaction to injury in images submitted by members as examples of healing. The second presented panel members with 28 pairs of serial images, 14 chosen to illustrate progression and 14 chosen to illustrate repair. Agreement was tested on 8 items: global judgment on which image in the pair was better, relative size of the erosion in the 2 images, judgment on which image was first, presence and extent of sclerosis, cortication, filling-in, remodeling, and reconstituting normal structure. Our results showed good agreement, among the 15 respondents, on global assessment of which image was better and which image showed the smaller erosion. Correct assignment of sequence was only slightly better than expected by chance (in 65% of the cases). Agreement was poor regarding the presence of morphologic features of bone repair. A majority of a panel of experts agreed on which 2nd images in a set of paired, serial images represented improvement and which showed progression based on global assessment of which was better and on size of erosion. Features of bone repair were not distinctive and did not enable the panel to deduce the correct sequence of the serial images. This study provides evidence that repair of bone damage in RA does occur, resulting in some degree of improvement, which was recognized by a majority of a panel of experts.  相似文献   
36.
Summary We have studied the interrelationship of total body fat mass, carbohydrate tolerance and IRI response in 17 non-obese and obese subjects, who were suspected of having early diabetes. We carried out an i.v. glucose infusion test consisting of a priming injection of 0.33 g/kg followed by constant glucose infusion of 12 mg/kg/min in all persons. Total body fat mass was estimated by the tritium dilution method. There was a positive correlation of body fat mass, fasting glucose concentration and blood glucose concentration at 150 min as well as a strong correlation between body fat mass and BG area 60–120 min as parameters of carbohydrate tolerance in all subjects, i.e. the degree of carbohydrate intolerance was directly related to the quantity of total body fat mass. A similar correlation was found when the non-obese and obese groups were analyzed separately. In neither group did total body fat mass correlate with parameters of IRI response. In obese subjects with pathological carbohydrate tolerance, however, a positive correlation of basal IRI concentration and total body fat mass was found. Furthermore, a close relation between basal IRI level and parameters of carbohydrate tolerance could be demonstrated in obese subjects. The present study failed to demonstrate any correlation of parameters of carbohydrate tolerance and glucose-induced IRI response in either group. Thus, the significant relationship between body fat mass and degree of carbohydrate intolerance indicates that total body fat mass plays an important role in the disturbance of blood glucose homeostasis in early diabetes with and without obesity. Investigation performed within the medical research project ‘Diabetes mellitus and disturbances of lipid metabolism’, Ministry of Health, GDR.  相似文献   
37.

Background:

Many patients with obsessive-compulsive disorder do not respond adequately to serotonin reuptake inhibitors. Augmentation with antipsychotic drugs can be beneficial in this regard. However, since new relevant randomized controlled trials evaluating new antipsychotics were conducted, a recalculation of the effect sizes appears necessary.

Methods:

We meta-analyzed all double-blind, randomized, placebo-controlled trials comparing augmentation of serotonin reuptake inhibitors with antipsychotics to placebo supplementation in treatment-resistant obsessive-compulsive disorder. The primary outcome was mean change in the Yale-Brown Obsessive–Compulsive Scale total score. Secondary outcomes were obsessions, compulsions, response rates, and attrition rates. The data collection process was conducted independently by 2 authors. Hedges’s g and risks ratios were calculated as effect sizes. In preplanned meta-regressions, subgroup analyses, and sensitivity analyses, we examined the robustness of the results and explored reasons for potential heterogeneity.

Results:

Altogether, 14 double-blind, randomized, placebo-controlled trials (n=491) investigating quetiapine (N=4, n=142), risperidone (N=4, n=132), aripiprazole (N=2, n=79), olanzapine (N=2, n=70), paliperidone (N=1, n=34), and haloperidol (N=1, n=34) were incorporated. Augmentation with antipsychotics was significantly more efficacious than placebo in Yale-Brown Obsessive–Compulsive Scale total reduction (N=14, n=478; Hedges’s g=-0.64, 95% CI: -0.87 to -0.41; P=<.01). Aripiprazole (Hedges’s g=-1.35), haloperidol (Hedges’s g=-0.82), and risperidone (Hedges’s g=-0.59) significantly outperformed placebo. Antipsychotics were superior to placebo in treating obsessions, compulsions, and achieving response. There was no between-group difference concerning all-cause discontinuation. The nonsignificant meta-regressions suggest no influence of the antipsychotic dose or baseline symptom severity on the meta-analytic results.

Conclusions:

According to our findings, antipsychotic augmentation of serotonin reuptake inhibitors can be regarded as an evidence-based measure in treatment-resistant obsessive-compulsive disorder.  相似文献   
38.
39.
The genetics of caloric restriction in Caenorhabditis elegans   总被引:11,自引:0,他引:11       下载免费PDF全文
Low caloric intake (caloric restriction) can lengthen the life span of a wide range of animals and possibly even of humans. To understand better how caloric restriction lengthens life span, we used genetic methods and criteria to investigate its mechanism of action in the nematode Caenorhabditis elegans. Mutations in many genes (eat genes) result in partial starvation of the worm by disrupting the function of the pharynx, the feeding organ. We found that most eat mutations significantly lengthen life span (by up to 50%). In C. elegans, mutations in a number of other genes that can extend life span have been found. Two genetically distinct mechanisms of life span extension are known: a mechanism involving genes that regulate dauer formation (age-1, daf-2, daf-16, and daf-28) and a mechanism involving genes that affect the rate of development and behavior (clk-1, clk-2, clk-3, and gro-1). We find that the long life of eat-2 mutants does not require the activity of DAF-16 and that eat-2; daf-2 double mutants live even longer than extremely long-lived daf-2 mutants. These findings demonstrate that food restriction lengthens life span by a mechanism distinct from that of dauer-formation mutants. In contrast, we find that food restriction does not further increase the life span of long-lived clk-1 mutants, suggesting that clk-1 and caloric restriction affect similar processes.  相似文献   
40.
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