Adeventivwurzelbildung an der Infloreszenz

Ohne Zusammenfassung     

In vitro inhibition of rat uterine contractility induced by 5α and 5β progestins

Ten natural progestins were evaluated for their capacity to inhibit the $\text{in vitro}$ motility of rat's uterus. Progestins with their ring A reduced in the 5β position were significantly more potent than Δ⁴-3 keto and 5α reduced progestins. These last progestins were ineffective to inhibit uterine motility excepting 3α-hydroxy-5α-pregnan-20-one which was slightly less effective than progesterone. The potency of the progestins to inhibit uterine motility was related to their capacity to induce membrane stabilization. The data indicates that 5β, but not 5α reduction of progesterone, may be important for regulating myometrial activity.     

Zooplankton,zoobenthos, and bottom sediments as related to pollution and water exchange in the Oslofjord

Summary 1. Increasing attention has been paid to pollution and oxygen shortage in the Oslofjord. Recently, a number of investigations were carried out (1962 to 1966) in cooperation with the Norwegian Institute for Water Research. The present article summarizes a few of the major results of some of these investigations, which are based on plankton samples (vertical hauls with a Nansen closing net), zoobenthos and hyperbenthos samples (towings along the bottom with Beyer's toboggan), and sediment cores (Moore & Neill corer).2.Aglantha digitale andRathkea octopunctata were found in greatest numbers in the most heavily polluted areas, where bottom water and sediment were generally anoxic and azoic.3. Spionidae, Hesionidae, and Nudibranchia thrived in polluted areas when these were not anoxic. The remaining of the benthos components compared occurred primarily in water of better quality. A consistent and distinct ranking order was found for all these components.4. In areas where no bottom fauna was found, and in transitional zones, black or dark layers in the sediment indicated various degrees of oxygen insufficiency.5. Combinations of toboggan towings and coring surveys provide a useful basis for classifications.6. Most remarkable differences (variations) were recorded in the successive years of the survey.

---

Zooplankton, Zoobenthos und Bodensedimente in ihrer Beziehung zur Verunreinigung und zum Wasseraustausch im Oslofjord

Kurzfassung Anhand von Untersuchungen, die mit Nansen-Netz, Clarke-Bumpus-Samplers, Schlittenschließnetz und Bodengreifer in den Jahren 1962 bis 1965 im Oslofjord durchgeführt wurden, ergab sich, daß der Artenreichtum der Fauna seewärts eine regelmäßige und stufenweise Zunahme zeigt, die besonders bei den Schlitten-Schließnetzfängen sehr ausgedehnt und deutlich zu beobachten war. Unter den planktonischen Tieren sindAglantha digitale undRathkea octopunctata und unter den benthonischen Tieren sind Spioniden und Hesioniden in verunreinigten Gebieten in sehr großer Zahl gefunden worden. Decapode Crustaceen zeigten hinsichtlich ihres Vorkommens eine starke Abhängigkeit von der Zufuhr sauerstoffreichen Wassers. In Gebieten, in denen gar keine Tiere mehr oder nur noch sehr wenige Arten periodisch leben konnten, erwiesen sich die Proben der Bodenablagerungen, die mit einem kleinen Schwerelot gewonnen wurden, dazu geeignet, verschiedene Fäulniszustände durch ihre Farbe zu charakterisieren. Sowohl in der Faunenzusammensetzung als auch im Oxydationszustand des oberen Sediments wurden sehr große Schwankungen während der Untersuchungsperiode beobachtet, die entweder mit Austausch oder Stagnierung des Bodenwassers verbunden waren.

     

Sexual behavior in male rats treated with estrogen in combination with dihydrotestosterone

Male rats castrated at 30 days of age were treated with estradiol benzoate (dose range: 0.05–50 μg EB for 26 days) and dihydrotestosterone (1 mg DHT for 36 days) as adults. The combined EB and DHT treatments resulted in display of male sexual behavior which did not differ from the behavior shown by intact untreated males or castrated, testosterone propionate (1 mg TP for 26 days) treated males. EB alone or DHT alone were relatively ineffective in activating male behavior in castrated males.