levan n (14 risultati)

paperback. Condizione: Good. Connecting readers with great books since 1972! Used textbooks may not include companion materials such as access codes, etc. May have some wear or writing/highlighting. We ship orders daily and Customer Service is our top priority!

Paperback. Condizione: Good. No Jacket. Pages can have notes/highlighting. Spine may show signs of wear. ~ ThriftBooks: Read More, Spend Less.

Condizione: Acceptable. Has tipped in page. Meets the acceptable condition guidelines. Has wear. Five star seller - Buy with confidence!

Condizione: New.

Condizione: As New. Unread book in perfect condition.

Soft cover. Condizione: Very good. No jacket. Third edition. Great condition. Cover is lightly shelf-worn, but binding is tight and inside is clean and unmarked.

Paperback. Condizione: Very Good. Paperback in very good condition. Highlighting on some inside pages. Other than that, all other inside pages are in great shape. Minor shelf wear to the cover.

Condizione: Fair. This is an ex-library book and may have the usual library/used-book markings inside.This book has soft covers. In fair condition, suitable as a study copy. Dust jacket in fair condition. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,450grams, ISBN:3540909001.

Condizione: Good. 3rd Edition. Pages intact with minimal writing/highlighting. The binding may be loose and creased. Dust jackets/supplements are not included. Stock photo provided. Product includes identifying sticker. Better World Books: Buy Books. Do Good.

Condizione: New.

Condizione: As New. Unread book in perfect condition.

PAPER BACK BLUE. Condizione: GOOD. Ring binding. General wear and rubbed cover. Black and white illustrations. No writings. RUSSELL TOLD ME HE HAD THESE PRIVATELY PRINTED. A LATER REVISION WAS PUBLISHED BY GATEWAY PRESS INC. 1998 AS Memories of Atlantic City, New Jersey The Queen of Resorts DATE PUBLISHED: 1997 EDITION: 468.

Lund, 1956. 4to. Minor signs of wear. A fine copy, With signature of "Joh. Holtfreter" to top of p. (1). 6 pp. + 1 plate. First printing, in the very rare off-print - Johannes Holtfreter's copy -, of the revolutionary paper that established for the first time the correct number of chromosomes in man, thus founding modern human cytogenetics. The present paper constitutes the most important breakthrough in genetics since Mendel. "The finding that the normal human diploid chromosome number was 46, rather than 48 as had been assumed for many years previously, represents the starting point of modern human cytogenetics, with great importance for future clinical applications in the detection of both constitutional chromosome abnormalities and somatic abnormalities such as those seen in cancers. This discovery, made 50 years ago at the Institute of Genetics of the University of Lund, Sweden, in December 1955 and published early in 1956 in the journal "Hereditas" (Tjio and Levan 1956), is now of historical as well as scientific importance." (Harper). "After 50 years, the paper of Tjio and Levan can be clearly seen as one of the major landmarks of human genetics, opening up the field of human chromosomes and of medical genetics generlly to detailed analysis, as well as fulfilling its original aim of providing a normal reference point for studies of chromosomes in cancer." (Harper).The rediscovery of Mendel's law at the end of the 19th century triggered intense interest in the principles of heredity" ever since that time, chromosome behavior had been studied scientifically, but although a great deal of scientific interest was directed towards learning more about chromosomes themselves, it wasn't until Joe Hin Tjio and Albert Levan's epochal discovery that the correct human chromosome count was established. For half a century it had been accepted that humans normally have 48 chromosomes - only due to Tjio and Levan were we to know that the chromosome number of man is actually 46. "Difficulties in determining the human diploid number arose for a variety of reasons. For one, early experiments that provided evidence for the chromosome theory often used invertebrate species that reproduced in large numbers and had a relatively low number of well-defined chromosomes. Neither of these characteristics, of course, is a common finding in humans. In addition, the human samples initially used for chromosome analysis were derived from fresh testicular tissue in which haploid meiotic cells were often present. Furthermore, what morphology could be deduced suggested that human chromosomes were more complex than those of the model organisms studied earlier. In light of these and other factors, an erroneous estimate by prominent cytologist Theophilus Painter dominated the field for decades, until researchers Joe Hin Tjio and Albert Levan eventually applied new technology to identify the true diploid number of human chromosomes." (O'Connor). As Painter's estimate of 48 chromosomes had been generally accepted from studies over the previous 30 years, study of normal human chromosomes was not an active research field in the mid-1950's. Albert Levan - one of the key figures in cancer cytogenetics -, however, extensively studied the chromosomes of human cancers and realized that it was necessary to be certain of the normal human karyotype. Likewise, Joe Hin Tjio - who then was primarily involved in plant cytogenetics - realized the importance and necessity in establishing the correct number. "In the decades following Painter's work, scientists continued to refine their methods for preparing chromosomes for microscopy. Sectioning of paraffin-embedded preserved tissue was gradually replaced by squash techniques, in which small tissue specimens are placed on a microscope slide and then literally squashed under a cover slip to produce a single layer of cells. This approach gained broad acceptance as it eliminated any need to slice through tissues and reconstruct th.

Leather Bound. Condizione: New. Language: English. Language: English. Presenting an Exquisite Leather-Bound Edition, expertly crafted with Original Natural Leather that gracefully adorns the spine and corners. The allure continues with Golden Leaf Printing that adds a touch of elegance, while Hand Embossing on the rounded spine lends an artistic flair. This masterpiece has been meticulously reprinted in 2025, utilizing the invaluable guidance of the original edition published many years ago in 1906. The contents of this book are presented in classic black and white. Its durability is ensured through a meticulous sewing binding technique, enhancing its longevity. Imprinted on top-tier quality paper. A team of professionals has expertly processed each page, delicately preserving its content without alteration. Due to the vintage nature of these books, every page has been manually restored for legibility. However, in certain instances, occasional blurriness, missing segments, or faint black spots might persist. We sincerely hope for your understanding of the challenges we faced with these books. Recognizing their significance for readers seeking insight into our historical treasure, we've diligently restored and reissued them. Our intention is to offer this valuable resource once again. We eagerly await your feedback, hoping that you'll find it appealing and will generously share your thoughts and recommendations. Lang: - English, Pages:- 264, Print on Demand. If it is a multi-volume set, then it is only a single volume. We are specialised in Customisation of books, if you wish to opt different color leather binding, you may contact us. This service is chargeable. Product Disclaimer: Kindly be informed that, owing to the inherent nature of leather as a natural material, minor discolorations or textural variations may be perceptible. Explore the FOLIO EDITION (12x19 Inches): Available Upon Request. 264 264.