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91.
92.
The specific features of the reproductive stage of the life cycle have been studied in the rhizocephalan barnacle Polyascus polygenea, a parasite of the coastal crab Hemigrapsus sanguineus. It is shown that a single crab can bear 1 to 8 externae of P. polygenea. The fecundity of the parasite depends on the size of the externae and their number on the host and may reach as much as 50000 eggs for one externa. In Peter the Great Bay, Sea of Japan, this species repeatedly reproduces during the entire spring–autumn period; externae with developing embryos in the mantle cavity occur from May to September, and planktonic larvae occur from June to October. One externa produces during the season of reproduction no less than three generations of larvae. Thus, the reproductive strategy in P. polygenea comprises a three-stage cascade of reproduction: asexual reproduction via budding of the interna; the development of several generations of one or several externae; and several reproduction cycles of each externa. This allows the parasite to produce a very great number of larvae and ensures the parasitization of a significant proportion of the host crab population. The structure of the ovaries and oogenesis in rhizocephalans and free-living cirripede barnacles have many common features, which provides evidence for integration of these two groups within one monophyletic taxon.  相似文献   
93.
The purpose of the present investigation was to enhance the efficiency of diagnosis of thyroid diseases in irradiated persons. Three hundred persons exposed to radiation in doses of 5 to 250 SeV and the postexposure period was 9 to 48 years. A control group comprised 100 military men unexposed to ionizing radiation. Thyroid ultrasound study and morphological diagnosis revealed diffuse nodular goiter transformation in 66% of the irradiated persons and malignant thyroid neoplasms in 3.7% whereas 38% of the control patients were found to have only benign diffuse nodular thyroid alterations and autoimmune thyroiditis (AIT). The investigation identified the echosemiotic features of nodular masses and AIT in the study group patients and established their association with the pathomorphological changes of the thyroid. The authors note the high efficiency of complex clinicoradiation and morphological studies in detecting thyroid pathology and the priority in establishing an accurate diagnosis at the preoperative stage and in determining management tactics.  相似文献   
94.
Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex.  相似文献   
95.
Data on the age and growth of the roughhead grenadier Macrourus berglax from waters off Southwest Greenland have been obtained based on the analysis of otoliths. Specimens with a preanal length of 5?39 cm, a weight of 7?5275 g, and age from 2 to 22 years are recorded in trawl catches. Roughhead grenadier exhibits a similar rate of linear growth in waters off Southwest Greenland and other parts of the range in the Northwest Atlantic. No considerable differences from the rate of the linear growth calculated earlier from scales for the species in waters off West Greenland have been found. In the recent period, the rate of weight gain in roughhead grenadier in waters off Southwest Greenland has been lower than in the Northwest Atlantic in the first half of the 1980s. The age of mass maturation in males (7–9 years) and females (16–17 years) in waters off West and East Greenland is somewhat higher than in coastal waters of Norway and the Northwest Atlantic.  相似文献   
96.
97.
The results of our study of the abundance dynamics of the great bustard population in the southern part of the Saratov Trans-Volga region for the period from 1998 to 2015 are presented on the basis of censuses carried out before the migration for wintering in the fall and on leks in the spring. The abundance dynamics was analyzed, and the factors causing it were identified. Data on the distribution of the great bustard population density over an account area of 12000 km2 are presented.  相似文献   
98.
The paper reviews the data available in the literature on the diagnosis of brain lesions in the central form of Recklinghausen's disease (neurofibromatosis) by magnetic resonance imaging. The results of a clinical observation of 10 children suffering trom neurofibromatosis and the data of electroencephalography, computed tomography and MRI are given and analyzed. Conclusions are made on the magnitude of and the most common site of MRI changes. It is suggested that MRI shows a higher sensitivity in detecting brain lesions in Recklinghausen's disease than other diagnostic techniques.  相似文献   
99.
Open randomized controlled clinical trials in which 161 patients were included showed that Affinoleukin (commercial drug which contains low molecular weight proteins obtained from extract of human leukocytes membranes) was effective in treatment of psoriasis. Affinoleukin, when added to regular treatment, accelerated the establishment of remission and its duration by restoration of impaired regulatory and defensive functions of T-lymphocytes, particularly, gamma deltaT- and NKT-cells as well as monocytes and NK-cells. Regular treatment led to marked positive effect in 45% of patients with severe psoriasis and psoriasis of intermediate severity. Addition of Affinoleukin in combined treatment increased proportion of patients with marked positive effect to 72%. Magnitude of Affinoleukin effect was directly related with its dose and severity of psoriasis. Course of Affinoleukin injections (up to 30 units in adults) is worthwhile to use as immunobiological component of combined treatment of exacerbations of severe psoriasis and psoriasis of intermediate severity.  相似文献   
100.
The seasonal dynamics of feeding spectra and diet of Arctic graying in a stretch of the middle reaches of the Yenisei River (from the dam of the Krasnoyarsk HPP to the mouth of the Kan River) was studied in 2009–2013. Its connection with the food-supply state and fish growth has been traced. It has been shown that the intensity of fish feeding is relatively stable throughout the year, despite significant fluctuations in zoobenthos biomass. The contribution of groups dominating in diet (amphipods and larvae of caddisflies) changes depending on the month. Amphipods prevail in the diet of fish during the period from June to October and caddisflies prevail in the winter and spring months. Among caddisflies, selective feeding on a small species, Apatania crymophila, has been revealed. The change of the primary diet component during the summer period corresponds to a sharp increase in the coefficients of relative condition factors with a peak in August–September. It has been assumed that changes in the ratio of weight and linear sizes of fish are associated not only with an increase in the water temperature, but also with the grayling switching to the consumption of amphipods with a higher nutrition value.  相似文献   
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