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61.
Zusammenfassung Die physikalischen Kräfte, die bei der Bildung einer Blase die Flüssigkeitsansammlung bewirken, waren bisher nicht gemessen worden. Es wurde der kolloidosmotische Druck in der Blasenflüssigkeit von mit einem modifizierten Dermovac erzeugten Saugblasen und in der Blasenflüssigkeit von Patienten mit Dermatitis herpetiformis, bullösem allergischem Kontaktekzem und Pemphigus vulgaris sowie im Serum von Normalpersonen mit Hilfe eines Membranosmometers bestimmt. Der kolloidosmotische Druck in den Saugblasen, die so schonend wie möglich produziert wurden, betrug etwa 7 cm H2O, in den durch eine Hautkrankheit entstandenen Blasen lag er etwa bei 20cm H2O, im Serum von Normalpersonen etwa bei 38 cm H2O. Der kritische kolloidosmotische Druck in einer Blase, der überwunden werden muß, damit eine Wanderung der Interstitialflüssigkeit in den Blasenraum erfolgt, errechnet sich aus dem Gewebsflüssigkeitsdruck und dem kolloidosmotischen Druck der Interstitialflüssigkeit, er beträgt etwa 15 cm H2O.
Physical forces in blister formationI. Direct Measurement of Blister Fluid Colloid Osmotic Pressure in Suction Blisters and in Bullous Diseases
Summary The physical forces operative in the fluid migration from the interstitial spaces into the blister cleft have not been directly measured until now. The colloid osmotic pressure was determined in suction blister fluid after mild suction blister production by a modified Dermovac and in blister fluid of patients with dermatitis herpetiformis, bullous allergic contact dermatitis and pemphigus vulgaris and in the sera of healthy persons. The colloid osmotic pressure was measured by means of a recently developed osmometer with a semipermeable membrane between two chambers, one of them filled with Ringer solution, the other with the blister fluid sample. The negative pressure in the first chamber was determined. The colloid osmotic pressure of suction blister fluid averages approximately 7 cm H2O, the values reach about 20 cm H2O in bullous diseases and about 38 cm H2O in the normal sera. The blister fluid colloid osmotic pressure has to rise to about 15 cm H2O or more to cause the fluid transport from the interstitial spaces of the surrounding tissue into the blister because of the negative interstitial fluid pressure and the colloid osmotic pressure of the interstitial fluid. Otherwise the blister fluid is reabsorbed back into the interstitial spaces.


Fräulein R. Brandmüller danke ich für die gewissenhafte Assistenz  相似文献   
62.
63.
Summary Evidence for a general role of phospholipase D in signal transduction is accumulating. In the present study, the activity of the enzyme was investigated in heart tissue under basal conditions and after addition of phorbol esters or aluminum fluoride (AlF inf4 sup– ; 10 mM NaF plus 10 M AlCl3). Atria of rats and chickens were incubated with [3H]-myristic acid in order to label preferentially phosphatidylcholine. Under basal conditions, the tissues generated choline and phosphatidic acid (PtdOH), the primary catalytic products of phospholipase D. When 0.5 or 2.0% ethanol was present, [3H]-phosphatidyl-ethanol (PETH) was rapidly formed at the expense of [3H]-PtdOH. This transphosphatidylation reaction is specific for phospholipase D activity. The basal formation of PETH was not inhibited by a Ca2+-free, EGTA-containing medium. - The phorbol ester 4-phorbol-12,13-dibutyrate (PDB), which is known to activate protein kinase C, enhanced the net formation of choline, whereas the inactive 4-phorbol-13-acetate (PAc) was ineffective. PDB (0.2 M), in contrast to PAc, also increased the formation of [3H]-PtdOH and, in the presence of ethanol, of [3H]-PETH. The PDB-evoked formation of PETH occurred again at the expense of PtdOH. Treshold and maximum effective concentrations of PDB were 10 nM and 0.2–0.6 M, respectively. The effects of PDB on either choline efflux and generation of PETH showed the same Cat+-dependency, i.e., both effects were blocked by a Ca2+-free, EGTA-containing medium, but not by a Ca2+-free medium without EGTA. In protein kinase C-deficient tissue which was prepared by pretreatment with 0.61 M PDB for 27 h, PDB failed to enhance the formation of PtdOH and PETH. - A1F4–, a known activator of G-proteins, increased not only the tissue content of inositol phosphates, but also markedly enhanced choline efflux and formation of [3H]-PtdOH and PETH. In conclusion, in mammalian and avian atria a high phospholipase D activity was found even under basal conditions. The enzyme was stimulated by protein kinase C and presumably by a G protein.Abbreviations IP inositol phosphate - DAG diacylglycerol - PL phospholipase - PtdOH phosphatidic acid - PETH phosphatidylethanol - PDB 4-phorbol-12,13-dibutyrate - PAc 4-phorbol-13-acetate - AlF inf4 sup– aluminum fluoride - DMSO dimethylsulfoxide Correspondence to K. Löffelholz at the above address  相似文献   
64.
Preoperative percutaneous transfemoral catheter embolization of feeding vessels in glomus jugulare tumors, followed by immediate application of standard surgical techniques, presents the treatment of choice, allowing meticulous microsurgery with virtually complete hemostasis. Therefore, the surgeon can operate in a bloodless environment throughout the compressed and intricate anatomic field, amidst such important yet vulnerable structures as cranial nerves, inner ear, carotid artery, jugular bulb, venous sinuses, and dura, while reducing surgical error and functional deficit for the patient. Review of the last 11 cases of glomus jugulare tumors at UCLA shows that even extensive Alford grade 2 tumors of the middle ear, jugular bulb, and mastoid had only minor blood losses with this combined technique of embolization-immediate surgery, as compared with earlier surgical methods. Pertinent literature on glomus jugulare and its treatment is reviewed. Combined embolization and immediate surgery offer the best approach for treatment of resectable glomus jugulare tumors.  相似文献   
65.
PURPOSE: Thymic epithelial tumors (TET) are rare epithelial neoplasms of the thymus with considerable histologic heterogeneity. This retrospective study focused on the correlation of WHO-defined TET histotypes with survival and tumor recurrence in a large cohort of patients receiving different modes of treatment. PATIENTS AND METHODS: Two hundred twenty-eight patients were followed for up to 21 years (median, 60 months; range, 1 to 252 months) after primary surgery. Forty-two patients received adjuvant radiotherapy (mean dose, 53 Gy), and 33 patients received adjuvant chemotherapy. RESULTS: Seventy-six (88%) of 86 patients with WHO type A, AB, and B1 thymomas were treated by surgery alone, with three tumor relapses after 3 to 10 years (median, 3.4 years). Twelve of 67 patients with WHO type B2 and B3 thymomas in Masaoka stages I and II were treated by adjuvant radiotherapy without evidence of tumor recurrence after 1 to 12 years (median, 4 years). Among 75 patients with B2 and B3 thymomas with incomplete resection or a tumor stage III or higher, the recurrence rate was 34% (n = 23) after 0.5 to 17 years (median, 5 years) in patients receiving adjuvant radiochemotherapy, compared to 78% (seven of nine patients) in patients without adjuvant radiochemotherapy. Incomplete tumor resection was associated with a high recurrence rate (65%) and a poor prognosis (P <.01). CONCLUSION: The long-term outcome of TET patients is related to tumor stage, WHO histotype, completeness of surgical removal, and type of treatment. Prospective trials are warranted to formally address the efficacy of adjuvant therapy in the treatment of localized and advanced malignant TETs.  相似文献   
66.
The t(12;21) translocation resulting in the TEL-AML1 gene fusion is found in 25% of childhood B-cell precursor (BCP) acute lymphoblastic leukemias (ALL). Since TEL-AML1 has been reported to induce cell cycle retardation and thus may influence somatic recombination, we analyzed 214 TEL-AML1-positive ALL by PCR for rearrangements of the immunoglobulin (Ig) and T-cell receptor (TCR) genes. As a control group, 174 childhood BCP ALL without a TEL-AML1 were used. The majority of TEL-AML1-positive leukemias had a higher number of Ig/TCR rearrangements than control ALL. They also had a more mature immunogenotype characterized by their high frequency of complete IGH, IGK-Kde, and TCRG rearrangements. While IGK-Kde and TCRG were more frequently rearranged on both alleles at higher age, IGH and TCRD rearrangements decreased in their incidence along with a decrease in biallelic IGH rearrangements. This suggests that the recombination process continues in these leukemias leading to ongoing rearrangements and possibly also deletions of antigen receptor genes. We here provide first evidence that somatic recombination of antigen receptor genes is affected by the TEL-AML1 fusion, and that further age-related differences are probably caused by the longer latency period of the prenatally initiated TEL-AML1-positive leukemias in older children.  相似文献   
67.
PURPOSE: The purpose is to investigate an additional antiemetic effect to ondansetron with needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture in patients undergoing high-dose chemotherapy and autologous peripheral blood stem cell transplantation. EXPERIMENTAL DESIGN: Eighty patients who were admitted to hospital for high-dose chemotherapy and autologous peripheral blood stem cell transplantation were included into a randomized placebo-controlled single-blind trial. The patients were randomized to receive acupuncture (n = 41) or noninvasive placebo acupuncture (n = 39) at the acupuncture point P6 30 min before first application of high-dose chemotherapy and the day after. All patients received 8 mg ondansetron/day i.v. as basic antiemetic prophylaxis. The main outcome measure was the rate of patients who either had at least one episode of vomiting or required any additional antiemetic drugs on the first 2 days of chemotherapy. RESULTS: The main outcome measure showed no significant difference (P = 0.82): 61% failure in the acupuncture group and 64% in the placebo acupuncture group (95% confidence interval of 3% difference: -18.1 and 24.3%). Comparing nausea, episodes of vomiting or retching and number of additionally required antiemetic drugs did not provide any discrepancy with the main result. CONCLUSIONS: This study suggests that in combination with ondansetron i.v., invasive needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture has no additional effect for the prevention of acute nausea and vomiting in high-dose chemotherapy.  相似文献   
68.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
69.
Hydroxyethyl starch (HES) solutions are widely used to replace intravascular volume. HES solutions differ from each other with regard to molecular weight and mode of hydroxyl substitution (degree of hydroxylation, C2:C6 hydroxyethyl ratio, concentration), factors which may have varying effects on coagulation. We studied, in vitro, three different HES preparations (molecular weight/degree of hydroxylation/concentration/C2:C6 ratio of substitution 70.000/0. 5/6%/3.2; Pharmacia & Upjohn Co., Erlangen, Germany; 130.000/0. 4/6%/11.2 and 200.000/0.5/6%/4.6; Fresenius Co., Bad Homburg, Germany) and, for comparison, lactated Ringer's solution (RL) at 33% and 66% dilution with whole blood. The influence of hemodilution was measured by using routine laboratory variables and SONOCLOT (Sonoclot II Coagulation and Platelet Function Analyzer, Sienco Co.) analysis, using a viscoelastic test, on the cellular as well as on the plasmatic hemostatic system. For statistical analysis of quantitative data, we used nonparametric analysis of variance and adequate post hoc tests. Qualitative data were analyzed by using the nonparametric Kruskal-Wallis test. A P value below 0.05 was considered significant. In contrast to the control group with RL, the liquid phase of coagulation (activated clotting time) was slightly affected by the 33% diluted HES solutions. HES 70.000, 130. 000, and 200.000 interfered significantly with the early stage of coagulation as expressed by the clot rate (gel/fibrin formation). Clot maturation and speed of maturation (time to peak) were strongly affected by HES 70.000 at all grades of dilution. HES 130.000 showed a faster clot formation process compared with the other HES solutions. HES 130.000 diluted 33% showed a better clot retraction as compared with the other HES solutions. In conclusion, in vitro hemodilution comparing different medium molecular weight HES solutions reveals that HES 130.000 seems preferable regarding some aspects of clot formation and retraction. RL affected clot formation only minimally, except for the early activation of clotting, which was measured by a shortened activated clotting time. IMPLICATIONS: We investigated the effect of different hydroxyethyl starch (HES) solutions (70.000, 130.000, 200.000) on coagulation. Regarding clot formation and retraction, HES 130.000 had some advantages over the other tested HES solutions. Lactated Ringer's solution affected coagulation only minimally, except for the early stage of clot formation.  相似文献   
70.
A comparison of autorefractor performance.   总被引:1,自引:0,他引:1  
PURPOSE: To compare the agreement between subjective refraction and autorefraction using two commercially available autorefractors. METHODS: Prospective data were collected for 190 subjects using either the Nidek ARK-700A (Fremont, CA) or the Topcon KR-8000 (Paramus, NJ) and subjective refraction (masked to autorefraction). Refractions were compared in terms of spherical equivalent using Bland-Altman limits of agreement and astigmatic vector difference using median and 95th percentile. RESULTS: The two groups were similar for age, gender, spherical equivalent, and astigmatic power. The differences in spherical equivalent between subjective and autorefraction were significantly different (mean +/- SD; Nidek, -0.03 +/- 0.36 D; Topcon, +0.11 +/- 0.34 D; analysis of variance, F = 7.84; p < 0.01). However, the 95% limits of agreement were similar: Nidek, -0.74 to +0.68 D; Topcon, -0.55 to +0.77 D. The median differences in astigmatic vector difference were also similar: Nidek, 0.27 D and Topcon, 0.25 D. However, the 95th percentile was 0.67 D for Nidek and 1.09 D for Topcon. There was a low frequency of large (>1.00 D) differences in spherical equivalent, 1.1% with each autorefractor. There were five cases with astigmatic vector difference >1 D, all with the Topcon KR-8000 (5.3%). CONCLUSIONS: Both autorefractors show excellent agreement with subjective refraction. Despite a statistically significant difference in mean spherical equivalent (0.14 D), near identical limits of agreement (0.10 D difference) suggest clinical equivalence. Conversely, for astigmatism, despite similar median scores, major outliers were more likely with the Topcon, reflected in a 0.42 D larger 95th percentile, which suggests a small advantage for the Nidek for avoiding large astigmatic errors.  相似文献   
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