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We report about the diagnostic and therapeutic approaches in 62 cases of Klatskin tumors operated during the last 5 years. In most patients the definite treatment consisted either of primary endoscopic drainage of the bile ducts or of a secondary endoscopic drainage after explorative laparotomy. Only one third of the patients could be operated in curative intention. Operative procedures included local tumor resections as well as a central bile duct resection combined with hemihepatectomy. The main problem in these operations is to avoid a biliodigestive anastomosis with tumor infiltrated bile ducts, because these patients would have been better treated endoscopically. After extended preoperative diagnostic procedures including CT-scan, ultrasound, ERCP and angiography in most cases the criteria for irresectability can be defined and unnecessary operative interventions can be avoided.  相似文献   
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Glutaraldehyde affects biocompatibility of bioprosthetic heart valves.   总被引:4,自引:0,他引:4  
A marked release of glutaraldehyde from commercially available pericardial bioprosthetic heart valve (BHV) material in washing solutions was found by high performance liquid chromatography (up to 1.8 ppm of glutaraldehyde per gram of dry tissue). In vitro endothelial cell proliferation rate was impaired dose-dependently in the presence of increasing glutaraldehyde concentrations of the cultivation medium (r = 0.9; p less than 0.05). Cultivation of endothelial cells was impossible on the surface of commercially available BHV material, but successful and uninhibited when toxic glutaraldehyde ligands of the BHV material were antagonized by treatment with L-glutamic acid.  相似文献   
5.
Brain metastasis from transitional cell carcinoma of the bladder is unusual, occurring most often in the presence of widespread systemic metastases. We report on a patient who presented with an isolated cerebellar metastasis and recurrent carcinoma of the bladder, after treatment with local excision and intravesical thiotepa. Further evaluation failed to demonstrate other distant metastases. Excision of the cerebellar lesion revealed transitional cell carcinoma identical to the original bladder tumor. In a review of the literature, we found reports of two similar patients in whom a solitary cerebellar lesion was the first sign of metastasis from carcinoma of the bladder; neither patient had evidence of other distant metastases, and neither previously had received systemic chemotherapy. These observations indicate that central nervous system metastasis from carcinoma of the bladder, while rare, should be considered in the differential diagnosis of solitary intracerebellar lesions in such patients.  相似文献   
6.
Summary Experimental testicular torsion must be used for certain studies of clinical relevance, but most experimental models either do not provide hemodynamic alteration comparable to the clinical situation or cannot guarantee reproducibility. Using a rat model arterial perfusion and hemorrhagic infarction were correlated to the degree of both intra- and extravaginal testicular torsion. Arterial inflow was measured sequentially with radiolabelled microspheres, hemorrhagic infarction was judged by the increase of testicular weight. Maximal hemorrhagic infarction and reproducible values were found when the spermatic cord was twisted togehter with the tunica vaginalis for 360°–540°.  相似文献   
7.
Elevated concentrations of hyaluronan (HA) are associated with the accumulation of macrophages in the lung after injury. We have investigated the role of HA in the inflammatory and fibrotic responses to lung injury using the intratracheal instillation of bleomycin in rats as a model. After bleomycin-induced lung injury, both HA content in bronchoalveolar lavage (BAL) and staining for HA in macrophages accumulating in injured areas of the lung were maximal at 4 d. Increased HA in BAL correlated with increased locomotion of isolated alveolar macrophages. HA-binding peptide was able to specifically block macrophage motility in vitro. Importantly, systemic administration of HA-binding peptide to rats before injury not only decreased alveolar macrophage motility and accumulation in the lung, but also reduced lung collagen alpha (I) messenger RNA and hydroxyproline contents. We propose a model in which HA plays a critical role in the inflammatory response and fibrotic consequences of acute lung injury.  相似文献   
8.
The results of five experiments showed that exposure to diazepam, hypoxia and monosodium glutamate during the prenatal or early postnatal period of rapid brain development may result in different behavioral consequences depending on the timing of the exposure rather than the nature of the agent. Moreover, male and female offspring may be affected differently by the same agent at different periods of development. Prenatal insults of various kinds impair the later performance of males but not the females in a complex learning task, while postnatal insults seem to affect detrimentally this same behavior in both males and females. The effects of perinatal insults on maze learning and open field activity do not lend themselves to explanation by "feminization" or "masculinization" of behavior caused by interference with prenatal gonadal hormones.  相似文献   
9.
A novel plasmid of about 7.8 megadaltons (MDal) could be detected in a non-penicillinase-producing Neisseria gonorrhoeae strain isolated in Munich in 1987. As the strain showed no resistance against commonly used chemotherapeutic agents, at present the plasmid must be described as phenotypically cryptic.Corresponding author.  相似文献   
10.
Poly(lactide-co-glycolide) microspheres containing different loads of OVA (0.05, 0.1, 0.5 and 1.0% w/w) were manufactured by a w/o/w emulsion/solvent evaporation method. Low load efficiencies of less than 20% were observed. Normal size distributions with mean volume diameters ranging from 3.7 to 4.7 µm were obtained for different batches. The in vitro release of OVA from different loaded microspheres showed an expected burst release with all batches. The in vivo dose study (1, 10, 25, 50 µg of OVA) was performed by subcutaneous and oral inoculation in mice by single (0 week) or double (0 and 3 weeks) administration of PLGA 50/50 microspheres containing 0.1% OVA. Subcutaneous administration showed an immune response (serum Ig levels by ELISA) statistically (Fishers paired t-test; P < 0.05) above OVA saline negative controls at 3, 6 and 12 weeks after administration. Oral administration of microspheres produced statistically higher systemic immune responses at the higher doses. Single and double inoculation orally and subcutaneously produced similar serum antibody levels. The in vivo load study was performed by subcutaneous and oral administration to mice of 25 µg OVA contained in various loaded (0.05, 0.1, 0.5 and 1.0% w/w) microspheres. Serum immune responses at 3, 6, and 12 weeks after inoculation were statistically above OVA saline controls and were inversely proportional to the OVA load using either route. This observation suggested a relationship between the number of microspheres delivered and the in vivo serum response. Single subcutaneous administration of 0.05 or 0.1% OVA loaded PLGA 50/50 microspheres induced larger immune responses compared with complete Freunds adjuvant.  相似文献   
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