Der Artikel ist weiterhin als ^^OTHERCONDITION^^ verfügbar.
Autor: Harold Kalter
ISBN-13: 9780306419881
Einband: Buch
Seiten: 300
Gewicht: 582 g
Sprache: Englisch
Erscheinungsdatum: 01.10.1985
1 The Role of the Obstetrician in the Prevention and Treatment of Birth Defects.- 1. Introduction.- 2. The Abnormal Conceptus.- 3. Causes of Birth Defects.- 4. Screening for Congenital Anomalies.- 4.1. Intrauterine Infections.- 4.2. Neural Tube Defects.- 4.3. Ultrasonography.- 5. Diagnosis of the Abnormal Conceptus.- 5.1. X-Ray.- 5.2. Ultrasound.- 5.3. Amniocentesis.- 5.4. Fetoscopy.- 5.5. Chorionic Villous Sampling.- 6. Management of the Abnormal Conceptus.- 6.1. Abortion.- 6.2. Fetal Surgery.- 7. The Future.- References.- 2 The Nature and Causes of Spontaneous Abortions with Normal Karyotypes.- 1. Introduction.- 2. Mechanisms of Abortion.- 3. Incidence of Chromosomally Normal Abortuses.- 4. Clinically Implicated Causes of Spontaneous Abortion.- 4.1. Infection.- 4.2. Immunological Factors and Spontaneous Abortion.- 4.3. Morphological Abnormalities.- 4.4. Abnormalities of the Uterine Environment and of Uterine Function.- 4.5. Endocrinological Factors.- 4.6. Maternal Disease and Spontaneous Abortion.- 4.7. Environmental Factors and Spontaneous Abortion.- 5. Summary.- 6. Conclusions.- References.- 3 Temporal Trends in Twinning.- 1. Introduction.- 2. Time Trends in Twinning Rates.- 2.1. Western Europe.- 2.2. Eastern Europe.- 2.3. United States.- 2.4. Canada.- 2.5. Japan.- 2.6. Other Countries.- 2.7. Summary: The Decline in Twinning in Recent Years.- 2.8. Variations in Twinning Rates over the Longer Term.- 2.9. Is the Drop in Rates Ending?.- 3. The Etiology of Twinning. Some Recent Findings.- 4. The Physiological Mechanism of DZ Twinning.- 5. Hypotheses Related to the Decrease in Twinning Rates.- 5.1. Age and Parity Distribution of the Maternal Population.- 5.2. The Differential Fecundability Hypothesis.- 5.3. Effects of Oral Contraceptives.- 5.4. Hypothesis of an Increase in Spontaneous Abortion.- 5.5. Decreased Sperm Counts or Sperm Quality.- 5.6. Coital Rates.- 5.7. Genetic Factors.- 5.8. Urbanization and Stress.- 5.9. Nutritional and Socioeconomic Factors.- 6. Conclusion.- References.- 4 Cytogenetic and Clinical Significance of Fragile Sites on Human Chromosomes.- 1. Introduction.- 2. Fragile Sites on Autosomes.- 2.1. Folate-Sensitive Fragile Sites.- 2.2. BUdr-Requiring Fragile Site 10q25.- 2.3. Fragile Site 16q22.- 2.4. Fragile Site 17pl2.- 2.5. Individual Folate-Sensitive Fragile Sites.- 2.6. Other, Not Yet Fully Accepted, Folate-Sensitive Fragile Sites.- 3. Fragile Site on the Human X Chromosome (Xq27).- 3.1. Hemizygotes.- 3.2. Heterozygotes.- 3.3. Cytogenetic Diagnostic Criteria.- 3.4. Amniotic Fluid Cell Cultures.- 3.5. Formal Genetics and Genetic Counseling.- 3.6. Location of the Fragile Site Mutation on the X Chromosome.- 4. X-Linked Mental Retardation without Cytogenetic Manifestation.- 5. Concluding Remarks.- References.- 5 Informative Morphogenetic Variants: Minor Congenital Anomalies Revisited.- 1. Background.- 2. Terminology; Definition.- 3. Quantification of Informative Morphogenetic Variants (IMV): Formal and Comparative Aspects.- 3.1. Properties of the Examination.- 3.2. Quality of the Examiners and Recording of Their Observations.- 3.3. Characteristics of the Population Examined.- 4. The Biology of Informative Morphogenetic Variation.- 5. The Specific and Nonspecific Value of Informative Morphogenetic Variants, Singly and in Combination.- 5.1. Single Informative Morphogenetic Variants.- 5.2. Combinations of Informative Morphogenetic Variants As Predictors, and Clues to the Temporal Origin and Pathogenesis of Defective Intellectual and/or Behavioral Development.- 6. The Use of Specific Aggregates of Informative Morphogenetic Variants for Diagnostic Purposes.- 7. The Application of Numerical Taxonomy to Informative Morphogenetic Variants for the Purposes of Classification and Nosology.- 8. Informative Morphogenetic Variants As Indices of Teratogenic Environments.- 9. How Can the Information Value of Morphogenetic Variants Be Increased?.- 9.1. Measurement of Graded Anthropometric Characters to Identify Informa
There is still no clear understanding of what causes the great majority of human congenital malformations. And since in most sorts of human disease and pathology that yet prevail prevention usually awaits understanding of cause, it is generally thought that the same is true of developmental aberrations. But is this true? For the relatively few congenital malformations whose causes are primarily environmental, it is plain that their discovery has enabled prevention, but not nec essarily immediately. It took a generation from the time of the discovery that maternal rubella was teratogenic to learn how to immunize against it. Much debate occurred before it was appreciated that thalidomide was a teratogen, and only its removal from the pharmacist's shelf and the end of the epidemic of limb defects attributed to the drug overcame the last doubts. For other proven environmental teratogens doubts and difficulties still con tinue. The claimed prevalence of fetal genital distortions due to female sex hor mones may have been exaggerated. Some potentially teratogenic therapeutic drugs, like anticoagulants, anticonvulsants, and anticancer chemicals, are still pre scribed despite this danger because of their benefits to pregnant women. For those congenital malformations whose basis is predominantly genetic or chromosomal it is different, however. Prevention has not been achieved by the discovery of such causes, as dramatic and revolutionary as some of them have been, except in the questionable sense of interference with reproduction by genetic coun seling or prenatal elimination. But this has not inhibited the romanticists.
Autor: Harold Kalter
ISBN-13:: 9780306419881
ISBN: 0306419882
Erscheinungsjahr: 01.10.1985
Verlag: Springer, Berlin
Gewicht: 582g
Seiten: 300
Sprache: Englisch
Sonstiges: Buch