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Biomedical subjects

R Kaden

Publications and source records attributed to R Kaden.

At least 19 recordsLinked to original sources
PubMed2005

[Cryopreserved human sperm deposits: usability after decades of storage].

To determine the effect of long-term storage on cryopreserved human sperm, 238 individual samples from 34 cryopreserved sperm deposits that had been collected between 1976 and 1989 were evaluated at regular intervals. The material was from 34 patients, 18 of whom suffered from underlying malignant disease. Every 3 years a sample from each deposit was thawed for microscopic analysis. During the course of the storage period limited to a maximum of 21 years, all ejaculate parameters had deteriorated in comparison to fresh semen. Quantitative motility was the most sensitive parameter with a decrease of ca. 80%. Sperm density decreased hardly at all. The parameters of the criteria investigated did not decrease linearly or proportionally with the storage duration, but rather more directly after the freezing process or within the first 3 years. These changes became increasingly smaller as the storage time lengthened. Almost all of the deposits exhibited adequate quality at all times during storage. Consequently, 21-year permanent frozen storage in liquid nitrogen is safe regarding aspects of spermatology.

Cryopreservation↗
PubMed1985

A new instant cryoprotectant for human sperm.

A new instant cryoprotectant, mainly containing culture medium, human serum albumin, and kallikrein, and its laboratory handling in the cryoprotection of semen are described. A comparative study distributed to three cryobiological centers using either egg yolk citrate medium or instant cryoprotectant showed that neither had a significantly better or worse mean percentage recovery rate. The advantage of the new instant cryoprotectant presented consists clinically in the absence of egg yolk and technically in its easy handling. Therefore, ICP is judged as an alternative to ECM in the cryopreservation of human sperm.

Citrates↗
PubMed1977

[Historic notices of Louis braille and the development of dot-writing (author's transl)].

Louis Braille is called by his first biographer to be the "Johannes Gutenberg for the blind". Being blind himself--caused by a sympathetic ophthalmia after a perforating hurt to his eye--he invented at the age of 16 years a simple and ingenious method enabling blind people to read and write. His system consisting of six elevated and palpable dots was rejected by the teachers of these days, claiming there could be a distance between blind and fullsighted men. Despite this opposition the Braille system succeeded because of its advantages for the blind: Nowadays this method is used all over the world.

Blindness↗
PubMed1976

[Reproduction and cohabitation disorders from the andrological viewpoint].

Analogous to gynecological fertility diagnostics as applied to women, the andrological methodology for the examination of men has been expanded into a simple and extended method of fertility diagnostics. Generally, the examination of a male patient begins with simple fertility diagnostics and is followed-up individually by detailed diagnostic procedures only when a certain suspicion exists. As a rule extended diagnostic procedures are not applied to a husband before the wife's ability to conceive has not first been determined at least by a simple gynecological examination. This proceeding sequence is rational and satisfying particularly since some fertility diagnostic interventions can only be imposed upon a patient after all other possibilities are exhausted. Primarily in cases of cohabitational disorders caused by male impotence, a similar diagnostic method is applied. As in the case of fertility examinations, all other possibilities, such as endocrinological malfunctions, metabolic disorders, disease symptoms and neurological defeciencies are thoroughly investigated. After all pathological findings are ruled out, psychoanalytical tests are advised. In most cases, behavioural disorders can be left to the guidance of the andrologist within the framework of minor sexual-psychological psychiatry. In more severe cases, specialized psychiatric diagnostic procedures are recommended. Although the classic spermiogram is still the focal point of diagnostics, normo-zoospermia is no longer necessarily synonymous with reproductive ability. Under given circumstances, differential diagnostic considerations are sometimes necessary taking the entire equipment of extended diagnostic procedures for granted.

Cytodiagnosis↗
PubMed1976

[Schnyder's corneal dystrophy and hyperlipidemia (author's transl].

Five out of ten members of a kinship were found to be affected by Schnyder's corneal dystrophy. Hyperlipoproteinemia was present in five out of eight cases examined (3 times type II, twice type IV). In one case with corneal dystrophy lipid levels were in the normal range, in another case, a child, hyperlipidemia was present without corneal abnormalities. The interrelationship of Schnyder's corneal dystrophy and disorders of lipoprotein metabolism is discussed. It is concluded that patients with Schnyder's corneal dystrophy and their relatives should be screened for hyperlipidemia; prophylactic treatment should be instituted when cases with hypercholesterinemia are found.

Adolescent↗
PubMed1975

[Testicular histology in the aging man].

In aged men beyond 50 years--regardless of claims of impotence or infertility--testicular biopsies are discussed. Generally speaking all biopsies show more or less histological changes due to old age. Reduced spermatogenesis, fibrosis of tubule walls and retrogression of Leydig cells are mostly seen. The morphological changes in Leydig cells reflect the usual cell failure more convincably than the decrease in number. Selected microphotographs represent characteristic biopsies in old age. These findings confirm the previous results of other investigators. The various histological changes explain the different intensity and the variety of the claims in aged men as definite signs for male climacteric.

Age Factors↗
PubMed1975

[Varicocele as a cause of disorder in fertility (author's transl)].

In this study the pathophysiological connections in varicocele genesis are discussed, as well as its effect upon spermiogenesis and the causal factors. In 73 patients the high retroperitoneal ligature of the testicular vein was performed. Indication was given either on the basis of subjective complaints or on the proof of subfertility. In 79% of the cases a good anatomic result was obtained after operation. Of the spermiograms established prior to operation 56% showed postoperatively a distinct improvement in quality. In 52% of the sterile marriages conception occurred following operative intervention. In our clinic the operative method according to Bernardi is preferred, since it meets best the criteria of an ideal varicocelectomy. Operative intervention should take place early for possible preventing of spermiogenetic lesion.

Adolescent↗