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271.
272.
Thermoregulatory and motor activity circadian cycles are age-dependent. While the level of thermoregulation and motor activity remained almost at the same level during the first 1–15 months during the light portion of the 24-hr cycle, a significant decrease in the level of both rhythms was observed during the dark period. Therefore, older rats exhibited reversed cycles compared with younger rats. Treatments with d-amphetamine resulted in the enhancement of reversal of the cycles. Rats treated with α-MSH failed to exhibit a reversal of the cycles. While the effects of d-amphetamine are mediated by the brain DA mesolimbic pathway, it seems that α-MSH acts on the dopaminergic system at different sites of action. 相似文献
273.
The lethality of T-2 toxin to adult femaleAedes aegypti mosquitoes was investigated using various methods of application: Topically, by injection, and by natural feeding. The technique of topical application was found to be the most precise, whereby an LD50 of 565 ng T-2 toxin/mosquito was determined. 相似文献
274.
A 37-year-old male patient with advanced refractory plasma cell myeloma underwent T-cell depleted bone marrow transplantation (BMT) after 7 years of active disease previously treated with combination chemotherapy and irradiation. After the BMT there was marked clinical improvement and the patient is currently in good clinical condition two years after the BMT was performed. However, residual myeloma cells are still seen in the marrow and stable levels of paraprotein are still present in the serum. No GVHD was encountered after BMT. The problems of BMT in myeloma are discussed with a review of the current pertinent literature. 相似文献
275.
Neutralizing Activity of Broadly Neutralizing Anti-HIV-1 Antibodies against Primary African Isolates
276.
277.
Nitzan Hershkovitz Aharon Oren Anton Post Yehuda Cohen 《FEMS microbiology letters》1991,83(2):169-172
Abstract: Specific stress polypeptides were detected in three drought-resistant cyanobacteria ( Phormidium autumnale , LPP4 and Chroococcidiopsis sp.) subjected to matric- and osmotic-water stress. Drought stress caused the induction of at least 2–3 new polypeptides of apparent molecular masses of 30 kDa and 40–45 kDa. The polypeptide of 30 kDa was located in the thylakoid membranes, and the 45-kDa polypeptide in the cytoplasm. When these cyanobacteria were exposed to salt stress polypeptides of similar size appeared. 相似文献
278.
Abstract. Pieces cut from colonies of the soft coral Dendronephthya hemprichi exhibited rapid and effective attachment to hard surfaces. Attachment involved development of root-like processes (RLPs), which appeared at the basal part of the fragment 4 days after its removal from the colony. The fine structural changes and cascade of cellular events occurring in the RLP before and after attachment were studied using SEM, TEM, and LM. The epidermis of the RLPs is actively involved in the attachment process and several distinct phases are documented: appearance of numerous oval vesicles, extrusion of these vesicles resulting in the formation of an outer layer composed of extracellular organic matrix and organellar debris, which functions as an adhesive device leading to initial attachment. The latter phase was followed by the formation of desmocytes, which develop in the RLP epidermis and function as anchoring devices, mediating the firm attachment of the fragment to the substrate. This is the first evidence among anthozoans that desmocytes play an active role in anchoring tissue to substrate and thus extends the range of functions exhibited by desmocytes among anthozoans. 相似文献
279.
A. Eisenthal Yechiel Goldman Yehuda Skornick Anna Gelfand Diana Buyaner Issac Kaver Alon Yellin Henry Yehoshua Beatriz Lifschitz-Mercer Amnon Gonnene M. Shinitzky 《Cancer immunology, immunotherapy : CII》1998,46(6):304-310
Hydrostatic pressure (P) combined with membrane protein crosslinking (CL) by adenosine dialdehyde (AdA) can render tumor
cells immunogenic. We have recently shown that PCL treatment of murine tumor cells augmented the presentation of MHC-restricted
tumor-associated antigens and enhanced cell-mediated immunity. In cancer patients inoculated with autologous PCL-modified
tumor cells, a significant delayed-type hypersensitivity response was elicited. Since the balance between cell-mediated immunity
and humoral immunity is reciprocally controlled by immunoregulatory cytokines, we have examined the proliferative response
and cytokine secretion pattern in cultures of human peripheral blood mononuclear cells (PBMC) stimulated by autologous PCL-modified
and unmodified tumor cells. These tumor cells were obtained from freshly resected tumor tissue of 16 patients with colon (8),
lung (4) and renal (4) carcinomas. The results demonstrated that PCL-modified tumor cells promoted an increase in PBMC proliferation
in 5 out of 8 (63%), 1 out of 4 (25%) and 4 out of 4 (100%) colon, lung and renal cell carcinomas. Fourteen of the above cultures
were also analyzed for the secretion of interleukin-10 and interferon-γ. Overall, a substantial decrease in IL-10 secretion
was detected in 9 out of 14 (64%) cultures while a reciprocal increase in interferon-γ secretion was noted in 8 out of 14
(57%) cultures. Our results confirmed that PCL-modified human tumor cells of different etiologies can modulate the pattern
of cytokines released from stimulated autologous lymphocytes. Such a procedure could prove valuable in the production of autologous
tumor vaccines.
Received: 8 January 1998 / Accepted: 9 April 1998 相似文献