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101.
Within a randomized European multicentre trial the time of onset, severity and progression of intracerebral haemorrhages (ICH) were investigated prospectively by serial cranial ultrasonography in 343 ventilated infants with severe respiratory distress syndrome (RDS) following instillation of single or multiple doses of a natural porcine surfactant (Curosurf). In 148/343 infants (43%) ICH was diagnosed (grade I or II: 22%, grade III or IV: 21%). In 26 cases (8%) ICH was present on the ultrasound scan prior to surfactant instillation at a median age of 6h. Incidence and severity of ICH was similar after single- or multiple-dose surfactant treatment. Using a logistic regression model the following risk factors predictive of ICH were defined: low birth weight, allocation to certain hospitals, vaginal delivery, Apgar score6, rectal temperature on admission 36°C, primary anaemia, acidosis prior to treatment, RDS grade IV in pre-treatment chest films and poor response to surfactant treatmentOur study provides supportive evidence that multiple doses of Curosurf do not increase the risk for ICH as compared to single-dose administration.A preliminary report of this work was presented at 8th International Workshop on Surfactant Replacement, Oslo, Norway, May 21 1993. The study was supported by grants of the German government (BMFT 93 607 27) and the German Research Council (Deutsche Forschungsgemeinschaft He 2072: 1–2). The surfactant used in the trial was prepared ang tested in Stockholm with the skilful technical assistance of Elin Arvesen, Bim Linderholm. Eva Lundberg, Gunhild Nilsson and Petru Popa (supported by the Swedish Medical Research Council (Project No. 3351) and Oscar II:s Jubileumsfond)Dedicated to the memory of Edgar (Eddi) Laufkötter, one of the most active trial collaborators, who died under tragic circumstances on April 10, 1994.  相似文献   
102.
103.
The cellular morphology and electrophysiology of the rat neocortex between embryonic day (E) 18 and postnatal day (P) 3 was studied in vitro by extracellular biocytin injections and whole-cell recordings, respectively. Most neurons were characterized by a small number of short-range dendrites and a main axon that was directed towards the white matter. Biocytin injections into the marginal zone and the cortical plate labeled far-reaching connections extending up to 2 mm in horizontal direction, indicating the existence of a dense network of long-range intrinsic projections in the neonatal cortex. Action potentials could be elicited as early as E18 and repetitive firing could first be observed at P0. Electrical stimulation of the immature cortex at various positions elicited polyphasic and long-lasting (up to 1 s) excitatory postsynaptic potentials and currents, which were significantly reduced in amplitude by a selective N-methyl-D-aspartate receptor antagonist. Our data indicate that the perinatal cortex manifests the structural and functional conditions for powerful excitatory interactions, which increase the likelihood for the generation of epileptiform activity during this developmental period. Copyright Copyright 1999 S. Karger AG, Basel  相似文献   
104.

Purpose

We compared the results of deoxyribonucleic acid (DNA) ploidy determinations performed by flow cytometry and image cytometry in transitional cell carcinomas of the bladder.

Materials and Methods

In 81 cases of transitional cell carcinoma of the bladder DNA indexes were measured by flow cytometry of bladder washings and tumor tissue samples, and by image cytometry of imprints from tumor tissue samples.

Results

There was good correlation between bladder washings and tissue samples analyzed by flow cytometry in 68 cases but aneuploidy was missed with bladder washings in 13 (16 percent). There was also good correlation between flow and image cytometry in 75 cases (92.59 percent) regarding the detection of aneuploidy. There was agreement between detection of aneuploidy and DNA index in 45 cases (55.5 percent), while both methods detected an aneuploid population in 30 (37 percent) but there was disagreement regarding DNA index. Aneuploid populations were missed by flow cytometry in 6 cases (7.4 percent). Furthermore, in 10 cases peridiploid peaks were found on the image cytometry histograms, which were not visible on flow cytometry. However, it was not possible to assess accurately if these were true peridiploid populations.

Conclusions

There is good overall correlation between DNA content measured by flow and image cytometry but image cytometry has the advantage of visual discrimination, permitting preferential selection and analysis of tumor cells. However, certain problems remain with image cytometry, particularly in the case of peridiploid peaks, which cannot be classified accurately as showing true peridiploid or right shifted diploid populations.  相似文献   
105.
Zusammenfassung Um den Einfluß des chirurgischen Traumas beim Ösophaguskarzinom auf das zelluläre Immunsystem zu erfassen, wurden perioperativ in einer prospektiven Studie die Aktivität der natürlichen Killerzellen sowie die Serumkonzentrationen von Interleukin-2, Interleukin-6 un TNF- bei transmediastinaler Dissektion (n=12) vs. transthorakaler En-bloc-Resektion (n=10) der Speiserörhre im Vergleich zu einer Kontrollgruppe mit thorakoabdominalen chirurgischen Eingriffen bei nicht maligner Grunderkrankung erfaßt. Die Bestimmung der NK-Zell-Aktivität erfolgte präoperativ sowie am 4. und 10. Tag postoperativ durch einen standardisierten Europiumchlorid-release-Assay unter Verwendung von K-562-Targetzellen, die Lymphokine Interleukin-2, Interleukin-6 und TNF- wurden zusätzlich am 1. und 7. Tag postoperativ mit stadardisierten ELISA-Assays bestimmt.In unserem Patientengut sank die NK-Zellaktivität am 4. postoperrativen Tag sowohl in der Kontrollgrupe al auch bei beiden Operations verfahren zur Speiseröhrenresektion signifikant (p<0,05) zum Ausgangswert: in der Kontrollgruppe durchschnittlich um 45%, nach transmediastinaler Speriseröhrendissektion (1-Höhlen-Eingriff) durchschnittlich um 34%, nauch transthorakaler En-bloc-Resektion (2-Höhlen-Eingriff) im Mittel um 63% zum präoperativen Wert. Die transthorakale En-bloc-Resektion der Speiseröhre führte durch das größere chirurgische Trauma zu einer stäkeren Abnahme der zytotoxischen Aktivität der natürlichen Killerzellen. Eine Suppression der immunologischen Tumorabwehr insbesondere in der vulnerablen perioperativen Phase kann damit indirekt das Risiko der Manifestation von hämatogene Metastasen auf dem Boden einer intraoperativen Tumorzelldissemination u. a. bedingt durch Tumormanipulation begünstigen und damit prognostisch relevant werden.
Influence of surgical trauma on natural killer cell activity in esophageal carcinoma following transmediastinal dissection compareed with transthoracic en bloc resection
In order to assess the impact of surgical trauma involved in the therapy of esophageal carcinoma on the cellular immune system, a perspective study was performed involving perioperative hematological parameters. The activity of natural killer cells and the serum concentrations of interleuin-2, interleukin-6 and TNF- were measured in 12 cases of transmediastinal dissection and 10 cases of transthioracic en bloc esophageal resection and compared to values of a control group of thoracic and abdominal surgical patients with non-malignant maladies. Natural killer cells assume a central role in the non-specific immunological response in tumor patients. Their main function is the destruction of tumor cells via cytotoxic activities amplified by the release of interleukin-2 and TNF-. Natural killer cell activity was measured prior to surgery and on postoperative days 4 and 10 using a standardized europium chloride release assay, utilizing K 562 target cells. Lymphokines interleukin-2, interleukin-6, and THF- were also measured on postoperative days 1 and 7 using standardized ELISA assays. The activity of natural killer cells in our patient group sank significantly (P<0.05) on postoperative day 4 and likewise in the control group and both study groups, activity sank to the original values. In the control groups, natural killer cell activity averaged 45% of preoperative values, in comparison with an average of 63% following transmediastinal esophageal carcinoma resection (one cavity procedure), and transthoracic en bloc resection patients only reached 61% of preoperative values, transmediastinal dissection patients assumed 75%, and 77% was achieved by control group members. Transthoracic en bloc resection of the esophagus led to a more extreme reduction in cytotoxic cellular activity owing to the greater surgical trauma. Suppression of the immunological tumor resistance, especially in the vulnerable perisurgical pahse, can have an indirect negative effect on the manifestation risk of hematogenic metastases owing to intraoperative tumor cell dissemination resulting from tumor manipulation and may thus be prognostically relevant.
  相似文献   
106.
Viable intraluminal tumor cells can penetrate a clinically intact rodent colonic anastomosis and give rise to perianastomotic tumor growth. The aim of this study was to determine whether transanastomotic cell migration can be prevented by fibrin-based tissue sealant. Following distal colonic transection and reanastomosis with 5/0 silk sutures, Fischer F344 rats were randomly allocated to three experimental groups. In Group A, a circumferential ring of tissue sealant was placed around the serosal surface of the anastomosis; in Group B, sealant was limited to 50 percent of the anastomotic circumference; and, in Group C, no sealant was applied. All rats then had 10 5 Mtln 3 carcinoma cells injected into the proximal colonic lumen via a rectal catheter. The incidence of perianastomotic tumor at 21 days was significantly lower in Group A (3 of 14 animals) than in Group B (11 of 16 rats) (P =0.012; Fisher's exact test) or Group C (10 of 14 rats;P=0.011). A further experiment demonstrated that sealant did not protect the anastomosis when tumor cells were instilled directly into the peritoneal cavity. A topical carcinocidal action therefore appears unlikely, but our results suggest that a circumferential anastomotic ring of fibrin sealant forms an effective mechanical barrier preventing intraluminal tumor cells from reaching the peritoneal cavity.  相似文献   
107.
"Encéphale isolé" cats were implanted with two push-pull cannulae, one in the left caudate nucleus and the other in the ipsilateral substantia nigra. L-3,5(-3)H-Tyrosine was introduced continuously into the caudate nucleus to study the release of 3H-DA. Glycine (10(-5)M) added to the superfusing medium of the push-pull cannula inserted into the substantia nigra reduced (25%) the spontaneous release of 3H-DA. Conversely, strychnine (10(-5)M) slightly stimulated the 3H-transmitter release. The inhibiting effect of glycine (10(-5)M) on 3H-DA release was no longer seen in the presence of strychnine (10(-5) M). The results support the hypothesis of a tonic glycinergic inhibitory control of the activity of the nigrostriatal dopaminergic neurons.  相似文献   
108.
Proctocolectomy for ulcerative colitis   总被引:3,自引:0,他引:3  
The majority of patients with ulcerative colitis can be managed satisfactorily throughout their lives by medical treatment, but a minority require colectomy. In severe attacks, emergency surgery is often required to save the patient's life. In chronic disease not responding well to medical treatment, elective colectomy will restore the patient to good health. Colectomy is also necessary for certain local complications, such as cancer, severe fistulas, and strictures. Prophylactic colectomy is indicated in patients with long-standing disease in whom there are factors associated with a high risk of developing cancer of the large bowel. For all these indications, it is our opinion that single-stage proctocolectomy is the operation of choice in the great majority of patients. Finally, we consider that the best results are obtained when the physician and the surgeon work together in the closest possible cooperation.  相似文献   
109.
Zusammenfassung Einige gebräuchliche Modelle unter den Viehbetäubungsapparaten verfügen über Gummipuffer und Rückholfedern. Durch diese Bestandteile wird der vorschnellende Bolzen gebremst und in seine Ausgangsposition zurückgebracht. Wenn man den Gummipuffer und die Rückholfeder vor der Schußabgabe entfernt, kann der Bolzen abreißen und zu einem frei fliegenden Geschoß werden. In einem Suizidfall ist unter solchen Umständen ein 17 cm langes Bolzenstück durch die Stirn in die Schädelkapsel eingedrungen.  相似文献   
110.
In 1949 a National Plastic Surgery Training Program was set up in Great Britain. At that time there was a relative shortage of trained specialists in such a new field, and a vast accumulation of wartime injuries and a backlog of untreated civilian cases. This situation has changed during the past 30 years so that emphasis in training has also had to adapt to include the subspecialties of hand surgery, microsurgery, craniofacial surgery, and aesthetic plastic surgery. The problems of training in aesthetic surgery and the formation of a new British Association of Aesthetic Plastic Surgeons are described.  相似文献   
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