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Biomedical subjects

R Kühn

Publications and source records attributed to R Kühn.

At least 91 records · Page 5Linked to original sources
PubMed1991

Major histocompatibility complex class II hyperexpression on B cells in interleukin 4-transgenic mice does not lead to B cell proliferation and hypergammaglobulinemia.

The murine interleukin 4 (IL4)-encoding cDNA expressed under the control of the immunoglobulin heavy chain enhancer/promoter was inserted into the mouse germ line. All B cells present in the IL4 transgenic mice show a marked increase in expression of class II histocompatibility (Ia) antigens compared to B cells from control mice. In vivo 5-bromo-2'-deoxyuridine incorporation and cell cycle analysis revealed no significant increase in B cell proliferation in spleens of IL4 transgenic mice compared to littermate controls. Likewise, serum immunoglobulin concentrations in IL4 transgenic mice were not increased. From these experiments we conclude that Ia hyperexpression on B cells per se does not induce activation of autoreactive T cells leading to B cell proliferation or hypergammaglobulinemia.

Animals↗
PubMed1991

[Clinical aspects and assessment of renal oncocytomas].

Oncocytomas represent a special category of renal tumors which can be clearly separated from the renal cell carcinomas by their typical histological presentation as well as by their clinical course. A clear cut preoperative diagnosis based on sonography, CT and angiography, however, is not yet possible. Between 1981 and 1990 16 patients (4 men, 12 women) with a mean age of 65 years underwent a radical tumor nephrectomy, with the histopathological diagnosis of an oncocytic adenoma, whose clinical and pathomorphological parameters were completely evaluated. Oncocytomas are rare, although increasingly found, tumors of the kidney with a benign clinical course. Up to date the treatment for these tumors has been nephrectomy, only rarely extirpation.

Adenoma↗
PubMed1990

Functional analysis of the internal translation initiation site of foot-and-mouth disease virus.

Mutagenesis of the large untranslated sequence at the 5' end of the genome of foot-and-mouth disease virus revealed that a region of approximately 450 nucleotides preceding the open reading frame of the viral polyprotein is involved in the regulation of translation initiation at two internal start sites. Variations in two domains of this region reduced the translation efficiency up to 10-fold, whereas an intermediate segment seemed to be less essential. A pyrimidine-rich sequence preceding the start codon was most sensitive in that conversion of single pyrimidine residues to purines decreased the translation efficiency strongly. The data are in agreement with a recently proposed general structural model for the internal ribosome entry site of the cardiovirusaphthovirus subgroup of picornaviruses (E. V. Pilipenko, V. M. Blinov, B. K. Chernov, T. M. Dmitrieva, and V. I. Agol, Nucleic Acids Res. 17:5701-5711, 1989). They suggest, however, that this model represents only a core structure for the internal entry of ribosomes and that foot-and-mouth disease virus and other members of the picornaviruses need additional regulatory RNA elements for efficient translation initiation.

Animals↗
PubMed1990

[Perspectives of an existential interdisciplinary body theory].

The existence analytical inquiry has developed corporal models that admit in their integrative-anthropological form fertile comparisons with a phenomenological radical immanence-philosophy of the constitution. The "body as partner" (W. Blankenburg) and the not objectivitical measurable connection of the "figure- and functionbody" contain estimates, to understand the body as living "I can" (Maine de Biran; Husserl) that means as really final subjectivity, ipseity or "soul", like the french phenomenologist Michel Henry from the creature of the not secularized affectivity has analyzed. With that the remained rests of the still from world categories imaginaried connection get powered (transcendence, sensuousness, settlement by Heidegger, Merleau-Ponty, Schütz for example) to conceive the body as not inferable absolute origin being. Seen interdisciplinary there from results a new foundation for an evidence as constitution-comprehension, that can psychological like therapeutical the pathogenous for instance theoretical world/constitution/soul-distortions help over-power.

Body Image↗
PubMed1990

[What is the benefit of systematic regional lymph node dissection in tumor nephrectomy?].

What is the benefit of an extended dissection of the regional lymph nodes in the treatment of renal cell carcinoma (RCC)? We evaluated the results of 511 consecutive patients which we operated on RCC. The data of 320 patients (SLD) who had an extended dissection of the regional lymph nodes have been compared with those of 191 patients (FLD) who had a dissection of none or only of a few nodes for staging reasons. All patients were nephrectomized under curative intent (M0) with a transabdominal approach. 1. The incidence of N+ in the SLD group was 17.5% and 10% in the FLD group. 2. The overall 5-year survival rates were 58% after FLD and 66% after SLD, the 10-year survival rates 38% after FLD and 54% after SLD (p less than 0.01). 3. The perioperative mortality of patients with extended dissection was 0.9%. We conclude from our data that the extended dissection of the regional lymph nodes significantly improves the prognosis of patients which were operated for RCC.

Carcinoma, Renal Cell↗
PubMed1989

Hebbian learning reconsidered: representation of static and dynamic objects in associative neural nets.

According to Hebb's postulate for learning, information presented to a neural net during a learning session is stored in synaptic efficacies. Long-term potentiation occurs only if the postsynaptic neuron becomes active in a time window set up by the presynaptic one. We carefully interpret and mathematically implement the Hebb rule so as to handle both stationary and dynamic objects such as single patterns and cycles. Since the natural dynamics contains a rather broad distribution of delays, the key idea is to incorporate these delays in the learning session. As theory and numerical simulations show, the resulting procedure is surprisingly robust and faithful. It also turns out the pure Hebbian learning is by selection: the network produces synaptic representations that are selected according to their resonance with the input percepts.

Humans↗
PubMed1989

Angiotensin-induced hypertension in the rat. Sympathetic nerve activity and prostaglandins.

To elucidate mechanisms of angiotensin II (Ang II)-related hypertension, we infused angiotensin (76 ng/min s.c.) into rats with minipumps for 10-14 days. Control rats received sham pumps. We measured blood pressure by tail-cuff, and the excretion of aldosterone and prostaglandins (PG) (PGE2, prostacyclin derivative 6kPGF1 alpha, and thromboxane [Tx] derivative TxB2). Angiotensin II increased blood pressure by 20 mm Hg by day 2 and by 90 mm Hg by day 10. Aldosterone excretion increased from 10 to 70 ng/day in Ang II rats by day 7. Urine PGE2 did not increase in angiotensin rats; however, both 6kPGF1 alpha and TxB2 excretion increased with angiotensin. Control rats had no changes in any of these parameters. A sympathetic component was tested in a separate group of angiotensin rats that received phenoxybenzamine (300 micrograms/kg/day) during angiotensin infusion; their increase in blood pressure of 40 mm Hg at 10 days was less than in those rats with angiotensin alone but more than in control rats. Phenoxybenzamine did not influence the angiotensin-induced increases in excretion of 6kPGF1 alpha or TxB2. Additional groups of conscious angiotensin and control rats were equipped with splanchnic nerve electrodes on day 14 for recording of sympathetic nerve activity. Angiotensin rats had greater basal sympathetic nerve activity than the control rats. Incremental methoxamine injections demonstrated altered baroreceptor reflex function in rats receiving angiotensin. We conclude that increased blood pressure with chronic angiotensin infusion is accompanied by increased production of aldosterone and increased sympathetic tone. The latter may be modulated by PG.

6-Ketoprostaglandin F1 alpha↗
PubMed1989

[Biography and transcendence within the human psychotherapy image].

However "psychical" is defined it presumes a view of man, his personality and incarnation of the world, that may no longer be justified by psychology itself. Disclosing of the according conception of man in the philosophical sense fortunately therefore belongs today to a critical self-understanding of the various schools in psychotherapy. Besides the attempt of profiting universally from this plurality of methods there may be seen a certain tendency of rediscovering a faithful biographics as anthropological consensus. It is without any doubt a necessary part of rehumanized education of psychiatrists to elucidate it beyond its immediate affective, cognitive and social importance.

Adaptation, Psychological↗
PubMed1988

Results of treating stage III and IV malignant non-Hodgkin's lymphomas (NHL).

Malignant non-Hodgkin's lymphoma (NHL) patients were enrolled and analyzed retrospectively in 2 successive study groups. The first group consisted of 57 patients divided into low- and high-grade malignant NHL according to the Kiel classification, the second one included 104 patients divided into low-, intermediate-, and high-grade malignant NHL. The more individualized and more intensive polychemotherapy of the 2nd group yielded clearly better treatment results compared to the first group, especially in high-grade malignant NHL. The complete remissions rose from 32% to 59%, the recurrence rates fell from 62% to 20%, the 5-year survival time of patients under age 30 increased from 0 to 48%. In intermediate-grade malignant NHL, intensive therapy yield results that are as beneficial as those of mild therapy in low-grade malignant NHL (5-year survival rate 62% and 65%, respectively).

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

[Pathogenetic synopsis of diverticular disease of the female urethra].

Diverticular disease of the female urethra is rare, but not so rare as assumed hitherto. The predominant theory is that diverticula urethrae is secondary to infection of the glandulae paraurethrales, but they can be easily pared out, and this together with their three-dimensional appearance with subdivision in side, undermines this theory. On the other hand, the known fact that urethral diverticula can be observed in female babies and girls of school age and also in urethral moulds of healthy young women, in which widened urethral glands can be found, supports the idea of a congenital origin. The irritability of the female urethra results from the fact that it is made up of two germ layers. Inflammation of paraurethral ducts causes secondary widening of small congenital diverticula of the female urethra. Proximally located diverticula can irritate sphincter function, as does invasive treatment. In some cases endoscopic therapy might be justified rather than plastic surgical removal via the vagina. The history, symptoms, diagnostis, histology and secondary pathology are indicated only very briefly.

Diverticulum↗
PubMed1988

[Life and freedom as a compulsion? Considerations of the relation of the phenomenology of life and analysis of existence].

The phenomenon of compulsion, unless it is seen as purely pathological, discloses in a peculiar way by an analysis of the situation in connexion with the immanence of life. Challenged by a given situation man must react immediately whereas the first origin of human existence is a state of passivity without any possible escapes. In so far freedom rests on a inevitableness, that reactualizes with every challenge by the daily situation. This "compulsion" to answer permits at the same time real freedom; for the clever and synthesic questions to life give way to the real tasks, that have to be settled at the moment.

Adaptation, Psychological↗
PubMed1986

[Mullerian duct cysts. A case report].

Muellerian duct cysts are rarely occurring, cystic lesions in the true pelvis, differing in size, derived from or continuous with the prostate and seminal vesicles. They mostly manifest themselves between the ages of 30-40 years. The most common symptoms are related to irritability and obstruction of the lower urinary tract as well as the rectum. Therapy is troublesome because of incomplete resection resulting in frequent recurrences and iatrogenic damages including incontinence and impotence. One case of Muellerian duct cyst with a history of several operations is reported.

Adenofibroma↗