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Volker Heinemann 《Breast cancer research and treatment》2003,81(1):43-48
Single-agent chemotherapy of metastatic breast cancer is the treatment of choice in patients with slow tumor progression and asymptomatic disease. In this patient group, the choice of drugs is based more on good tolerability than on efficacy. By contrast, symptomatic or rapidly progressing disease requires the use of highly active regimens where more weight is put on reliable antitumor activity. While anthraycline-based combination regimens have set the standard of effective treatment, the addition of docetaxel (and to a lesser extent paclitaxel) has improved tumor response, but failed to induce a consistent prolongation of survival. Based on retrospective analyses, it is hypothesised that the combined use of anthracyclines and taxanes in first-line therapy may be most beneficial in defined subgroups: after adjuvant chemotherapy, in patients with HER-2 gene amplification, possibly also in patients with rapidly progressing visceral disease. 相似文献
13.
Abstract Kyphoplasty and vertebroplasty have become recognized procedures for the treatment of vertebral fractures, especially in patients
with osteoporosis. In most cases of osteoporotic spinal vertebral fracture in elderly patients, polymethylmethacrylate (PMMA)
cement is used to fill the defect and stabilize the vertebral body. The techniques of vertebroplasty and kyphoplasty differ
in the possibility of realignment and reconstruction of the vertebral body and spinal column. Long-term results in terms of
integration of the cement and bioreactivity of the vertebral body are still lacking; so, these procedures are still no options
in the treatment of younger patients. Vertebroplasty and kyphoplasty show different success in the management of fresh traumatic
spine fractures. The acute traumatic vertebral fracture has to be classified sensitively, to find the right indication for
cement augmentation. Mild acute compression fractures can be treated by vertebroplasty or kyphoplasty, severe compression
and burst fractures by combination of internal fixation and kyphoplasty. The indications for use of biological or osteoinductive
cement in spinal fracture management must still be regarded as restricted owing to the lack of basic biomechanical research
data. Such cement should not be used except in clinical studies. 相似文献
14.
Felix Eckstein Maiko Matsuura Volker Kuhn Mathias Priemel Ralph Müller Thomas M Link Eva-Maria Lochmüller 《Journal of bone and mineral research》2007,22(6):817-824
In this study, we characterize bone microstructure, specifically sex differences, at multiple skeletal sites in 165 subjects >52 yr of age, using microCT technology in vitro. Significant sex differences are observed at the distal radius, femoral neck, and femoral trochanter, but not at the iliac crest, calcaneus, and lumbar vertebral body. Correlations in BV/TV between sites ranged from r = 0.13 to 0.56. INTRODUCTION: The goals of this study were (1) to assess potential sex differences of bone microstructure and their difference between skeletal sites and (2) to explore the relationship of trabecular microstructural properties between relevant skeletal sites. MATERIALS AND METHODS: Trabecular bone microstructural properties were measured in vitro in 165 subjects 52-99 yr of age using microCT. Defined volumes of interest (cylinders with 6 mm diameter and 6 mm length) were scanned at a resolution of 26 microm (isotropic) in six different anatomical sites: distal radius, femoral neck and trochanter, iliac crest, calcaneus, and second lumbar vertebral body. RESULTS: At the radius and femoral neck, trabecular bone displayed a more plate-like structure, thicker trabeculae, smaller separation/higher trabecular number, higher connectivity, and a higher degree of anisotropy in men than in women (p < 0.05). At the trochanter, men displayed more plate-like structure and thicker trabeculae (p < 0.05), but no differences in trabecular separation or other parameters compared with the women. At the calcaneus, iliac crest, and second lumbar vertebra none of the bone parameters displayed significant differences between sexes. The BV/TV at one site explained a range of only 2-32% of the variability at other sites. CONCLUSIONS: These results suggest that trabecular bone microstructural properties are remarkably heterogeneous throughout the skeleton. Significant differences between men and women are observed at some, but not at all, sites. The magnitude of sex differences in trabecular microstructure coincides with that of fracture incidence observed for some of the sites in epidemiological studies. 相似文献
15.
Woltmann Alexander Thannheimer Andreas Hauck Stefan Bhren Volker 《Trauma und Berufskrankheit》2003,5(2):s293-s295
Abdominal infection has the fifth highest incidence of all posttraumatic infections but has the second highest mortality rate with 25%,pneumonia,with 29%, being the only posttraumatic infection that is more frequently lethal.Posttraumatic abdominal sepsis, on the other hand, has a mortality rate of almost 50%.This rate cannot be reduced except by prompt identification of the correct diagnosis of the underlying injury or complication.This means that delayed laparotomy is strikingly detrimental in these patients, with 46% mortality as opposed to 11% in patients who undergo laparotomy promptly. In parallel with this, the mortality of fresh-onset and localized peritonitis is 14%,whereas that of diffuse purulent peritonitis is up to a devastating 42%. 相似文献
16.
The presence of messenger RNA for HLA class I in human platelets and its capability for protein biosynthesis 总被引:1,自引:0,他引:1
Sentot Santoso Rainer Kalb Volker Kiefel Christian Mueller-Eckhardt 《British journal of haematology》1993,84(3):451-456
Summary. In order to determine whether platelets contain specific messenger RNA encoding for HLA class I molecules, polymerase chain reaction (PCR) was performed with RNA from different platelet donors. Two amplified 300 bp and 279 bp cDNA fragments were obtained which encompassed sequences from 321 to 620 and from 795 to 1073. The 300 bp fragment encodes exon 2 and exon 3, the 279 bp encodes a portion of exon 4, exon 5, exon 6 and a portion of exon 7. A 300 bp nested PCR product from one donor, that encoded for the highly polymorphic region α2, was cloned and sequenced. The resulting nucleotide sequences fitted to the expected sequence for HLA B*3801 of this donor. Sequence analysis of the 279 bp PCR product demonstrated the presence of exon 5 encoding for the 117 bp transmembrane domain.
In addition, de novo protein biosynthesis was studied by radioimmunoprecipitation of HLA class I molecules from35 S-methionine metabolically labelled platelet lysates with a monoclonal antibody (mab) w6/32 specific for a monomorphic epitope on the heavy chain of HLA class I antigens. Analysis of the immunoprecipitates on SDS polyacrylamide gel electrophoresis showed a specific band with apparent molecular weight (Mr ) of 44 kD corresponding to integral membrane HLA protein.
On the basis of these results, we conclude that platelets contain specific messenger RNA encoding for HLA class I molecules and have the capability to synthesize the integral HLA membrane protein. 相似文献
In addition, de novo protein biosynthesis was studied by radioimmunoprecipitation of HLA class I molecules from
On the basis of these results, we conclude that platelets contain specific messenger RNA encoding for HLA class I molecules and have the capability to synthesize the integral HLA membrane protein. 相似文献
17.
In order to study its possible use as a chiral membrane probe, small unilamellar vesicles of 1,2-bis(2,4-octadecadienoyl)-sn-glycero-3-phosphorylcholine (DODPC, 1 ), a doubly unsaturated phospholipid molecule, and vesicles of 1,2-dipalmitoyl- or 1,2-dimyristoyl-sn-glycero-3-phos-phorylcholine or egg-lecithin, containing DODPC, were prepared and investigated by UV and circular dichroism (CD) spectroscopy. The phase transitions that are clearly manifest in the UV effect reproducible but only small changes in the CD. This indicates that at least in the area of unsaturation the molecule is rather stiff and insensitive to its micro-environment. A non-membrane-forming short-chain model compound, 1,2-bis(2,4-hexadienoyl)-sn-glycero-3-phos-phorylcholine, 2 , was used to study the chiroptic properties of the isolated molecule; the results are in agreement with calculations and support the contention that bis-unsaturated lipid molecules should in principle be able to function as chiral labels. 相似文献
18.
19.
To support blood supply in the growing field of cancer surgery and to avoid transfusion induced immunomodulation caused by the allogeneic barrier and by blood storage leasions we use intraoperative blood salvage with blood irradiation. This method is safe as it provides efficient elimination of contaminating cancer cells, and as it does not compromise the quality of RBC. According to our experience with more than 700 procedures the combination of blood salvage with blood irradiation also is very effective in saving blood resources. With this autologous, fresh, washed RBC a blood product of excellent quality is available for optimal hemotherapy in cancer patients. 相似文献
20.
Benedikt Preckel Detlef Obal Jost Möllenheim Juliane Hennes Marc Heiderhoff Volker Thämer Wolfgang Schlack 《Journal canadien d'anesthésie》2006,53(11):1118-1125
PURPOSE: Frequency potentiation is the increase in force of contraction induced by an increased heart rate (HR). This positive staircase phenomenon has been attributed to changes in Ca2+ entry and loading of intracellular Ca2+ stores. Volatile anesthetics interfere with Ca2+ homeostasis of cardiomyocytes. We hypothesized that frequency potentiation is altered by volatile anesthetics and investigated the influence of halothane (H), sevoflurane (S) and desflurane (D) on the positive staircase phenomenon in dogs in vivo. METHODS: Dogs were chronically instrumented for measurement of left ventricular (LV) pressure and cardiac output. Heart rate was increased by atrial pacing from 120 to 220 beats x min(-1) and the LV maximal rate of pressure increase (dP/dt(max)) was determined as an index of myocardial performance. Measurements were performed in conscious dogs and during anesthesia with 1.0 minimal alveolar concentrations of each of the three inhaled anesthetics. RESULTS: Increasing HR from 120 to 220 beats x min(-1) increased dP/dt(max) from 3394 +/- 786 (mean +/- SD) to 3798 +/- 810 mmHg sec(-1) in conscious dogs. All anesthetics reduced dP/dt(max) during baseline (at 120 beats x min(-1): H, 1745 +/- 340 mmHg x sec(-1); S, 1882 +/- 418; D, 1928 +/- 454, all P < 0.05 vs awake) but did not influence the frequency potentiation of dP/dt(max) (at 220 beats x min(-1): H, 1981 +/- 587 mmHg x sec(-1); S, 2187 +/- 787; D, 2307 +/- 691). The slope of the regression line correlating dP/dt(max) and HR was not different between awake and anesthetized dogs. Increasing HR did not influence cardiac output in awake or anesthetized dogs. CONCLUSION: These results indicate that volatile anesthetics do not alter the force-frequency relation in dogs in vivo. 相似文献