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141.
Ohne Zusammenfassung
Schweitzerbartsche Veriagsbuchhandlung, Stuttgart 相似文献
142.
Szalińska Ewa Orlińska-Woźniak Paulina Wilk Paweł 《Journal of Soils and Sediments》2020,20(6):2641-2652
Journal of Soils and Sediments - This study analyzes the variability of sediment loads under variant climate change and land use scenarios in a Carpathian catchment with a dam reservoir. The areas... 相似文献
143.
Dr. Kurt Stübner 《Journal of pest science》1952,25(7):97-100
Ohne Zusammenfassung 相似文献
144.
Anita Sønsteby Arnfinn Nes Finn Måge 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):128-134
The effects of bark mulch and NPK fertilizers on yield and leaf and soil nutrient status of ‘Korona’ strawberry plants (Fragaria×ananassa Duch.), were studied over a period of three years. A significant effect of mulching was found in the first harvest year, but additional fertilizer did not affect total yield. Bark mulch slightly decreased the level of leaf nitrogen, but increased the level of leaf phosphorus and potassium in all years. Bark had a significant, negative effect on soil nitrate and ammonium content in the two first seasons. Mulching increased the soil moisture content in all years. 相似文献
145.
The ultrastructure of the flame cell, excretory capillaries, ducts, collecting ducts, excretory bladder, and excretory pore of Brachylaimus aequans was studied 6-8 days p.i. The excretory ducts, collecting ducts and excretory bladder are provided with numerous lamellae on the luminal side. The cilia of lateral flames in the excretory ducts have a triated rootlet. The excretory pore is covered by a tegument identical with the body tegument. The syncytium of the excretory bladder is connected with the tegument of the excretory pore by means of a septate desmosome. No lipid or excretory corpuscles have been demonstrated in the excretory system. 相似文献
146.
We tested the virulence of 15 strains of Entamoeba histolytica, imported to Czechoslovakia, by intracaecal inoculation of laboratory rats. According to the scoring system of Neal, none of the 15 strains possessed the virulence index greater than 2. This indicates that all the organisms tested should be classified as avirulent. However, it should be noted that all the strains produced infection of the caecum and thus should be considered infective for rat. For 7 strains, isoenzyme patterns were determined for PGM, HK and ME. One imported strain, obtained from student from Congo, demonstrated isoenzyme pattern for PGM and HK indicated that the strain was virulent. This organisms had the index of virulence 1.8 (avirulent) in animal experiment; it was isolated from cysts of clinically asymptomatic patient. Examination of the rectal mucosa of the donor of the strain indicated typical chronic catarrhal proctitis of mild degree. Examination of the patient's serum demonstrated the presence of anti E. histolytica antibodies by CIEP, while the ELISA test was negative. Twenty-one cyst carriers were examined by rectoscopy. Pathologic changes were observed in 20 of these, as follows: altered vascular structure (13X), roughened mucosa (12X), mucosal reddening (10X), decreased glistening (7X), mucus in mucosa (5X), inflammatory pseudopolypes (2X), ulcers (2X), enanthema (1X). Histological biopsies were obtained in 15 cases. One was considered normal. Remaining 14 biopsies exhibited following morphological changes: increased mucus secretion (8X), edema (7X), lymphocytic and plasmocytic infiltration (6X), lymphocytic and plasmocytic infiltration in addition to the presence of eosinophilic granulocytes (6X), presence of mucophages (5X), haemorrhages (4X), increased vascularity (3X), lymphocytic and plasmocytic infiltration with presence of extremely abundant eosinophilic granulocytes (1X), erosive-ulcerative changes of mucosa (1X). The changes observed indicated chronic catarrhal proctitis with expression to greater or less degree of signs of chronic catarrhal inflammation. 相似文献
147.
The process of colonization of Ascaris lumbricoides eggs by the fungus Verticillium chlamydosporium was studied by scanning electron microscopy. The preparations were made by fractionation of egg suspension exposed to the fungus for four days and frozen in liquid nitrogen according to St?rba and Milácek (1986). Ovicidal fungus forms an abundant ramifying mycelial network in the area between the eggs. However, egg-shells are penetrated only by some hyphae without any penetration organs produced (simple hyphal penetration). In a liquid medium, after penetration, hyphae inside the eggs rapidly grow among inner structures of egg-shells and on the surface of developing larvae. In the next phase, hyphae colonize the developing larva. The eggs attacked by this fungus remain morphologically unchanged for a long time except the sites of penetration. Verticillium chlamydosporium is a fungus with unique ovicidal properties. It colonizes the eggs of Ascaris lumbricoides at all stages of embryo development and also attacks larvae inside the eggs. 相似文献
148.
Two pairs of hitherto unknown multiciliate sensory endings have been demonstrated in free-swimming cercariae of Echinostoma revolutum using transmission and scanning electron microscopy. This type of receptor consists of a bundle of 36--40 short, conically projecting cilia ensheathed by a collar formed by a circular evagination of tegument in shape of a cup. The cilia projecting from the centre of a widened nerve fibre, filled with electron-lucid vesicles, possess a well developed basal body and do not contain a ciliary rootlet. The function of this receptor is discussed. 相似文献
149.
Stöcklin-Gautschi NM Guscetti F Reichler IM Geissbühler U Braun SA Arnold S 《The Journal of small animal practice》2001,42(8):413-416
A focal uterine adenomyosis is described in two bitches. In both cases, the uterus showed knobbly enlargements of 4 to 8 cm in diameter, which resulted in distinct clinical symptoms. Other pathological changes of the uterus were not present. One bitch was presented because of a history of vaginal discharge of several months' duration. Radiographs, as well as ultrasonography, revealed a soft tissue lesion at the cervix. The other bitch showed a marked reduction in its general condition and a sudden onset of a tense abdomen. Radiologically, a lesion of soft tissue opacity was observed in the mid-abdomen and was seen to originate from the left uterine horn during exploratory laparotomy. A torsion of the lesion was present, which explained the clinical signs in this second case. 相似文献
150.
Stärk KD 《Schweizer Archiv für Tierheilkunde》2001,143(2):63-68
Sustainable animal production requires a healthy production system including healthy animals producing wholesome products. Epidemiology as a discipline is concerned with the occurrence of disease or disease indicators in populations as well as with factors influencing disease occurrence. By providing this information, epidemiology contributes significantly to the development and maintenance of healthy livestock. This is illustrated with the example of the enzootic pneumonia (EP) eradication programme of Switzerland. A series of observational studies were conducted in order to obtain the necessary knowledge to implement an area-wide EP eradication programme. The issues of economical eradication strategies at the herd level and the risk of re-infections were addressed. Simulation modelling and economical analysis were also applied. These research projects led to the successful start of a national eradication programme. The example of the EP eradication programme illustrates that applied epidemiological research provides critical information for the planning, implementation and evaluation of disease control programmes and is thus a key tool in developing sustainable animal production. 相似文献