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181.
The effect of immunotherapy using sizofiran (SPG) on the prognosis of patients with ovarian cancers was prospectively studied in a total of 68 patients, who were randomly assigned to either a cisplatin, adriamycin and cyclophosphamide (PAC) therapy group or a PAC plus SPG combination therapy group.The survival rate was significantly higher in patients with stage Ic, II or III cancers treated with the PAC plus SPG combination, compared with the patients treated with PAC alone. In the SPG-receiving patients with stage Ic or more advanced cancers who were treated with four cycles or more of PAC, the outcome was improved (Cox-Mantel, p=0.074; generalized Kruskal-Wallis, p=0.032). Similar improvement was also observed in the patients with non-serous adenocarcinomas (Cox-Mantel, p-0.076; generalized Krukal-Wallis, p=0.045). No side effects attributable to SPG were recorded.The present results suggest that the use of SPG in combination with long-term chemotherapy improves the postoperative prognosis in ovarian cancer patients.Abbreviations SPG sizofiran  相似文献   
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Summary The effect of sciatic nerve transection on its centrally located terminals in the spinal cord was analyzed by electron microscopy in adult rhesus monkeys one and three months following lesion. Although the peripheral and intermediate portions of the dorsal roots, where the axons are enveloped by Schwann cells were normal, their central portion and their terminals in the substantia gelatinosa were remarkably altered. Transganglionic degenerative atrophy (TDA) is characterized by three distinct types of electronmicroscopic alterations. The first type exhibits a conspicuous electron density of the terminal and pre-terminal axoplasm. Importantly, shrinkage replaces fragmentation and glial engulfement of the terminal seen in the course of Wallerian degeneration. The second type is characterized by the disappearance of synaptic vesicles from the terminals. The third type of TDA consists of intricate labyrinthine structures, composed of flattened profiles of axonal, dendritic and glial elements. The complex and diverse cellular changes that occur in the upper dorsal horn following peripheral nerve injury may provide the structural basis of plasticity of the primary nociceptive system.  相似文献   
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Prostacyclin infused intravenously in human volunteers induces ex vivo inhibition of platelet aggregation, tachycardia and hypotension. The inhibition of platelet aggregation is obtained with slightly lower doses than those which exhibit cardiovascular effects.The cardiovascular effects disappeared within a few minutes after discontinuing the infusion of prostacyclin but the platelet effects were longer lasting.Prostacyclin did not have any effect on platelet count, platelet factor 3, accelerated partial thromboplastin time, prothrombin time, euglobulin clot lysis time, fibrinogen degradation products, blood glucose concentration or urine sodium potassium ratio.  相似文献   
186.
There are few formally documented proficiency testing programs for cytology laboratories, and those that have been documented are not entirely comparable in format. The first of three papers documenting a mandatory universal proficiency testing program for cytology laboratories in the Province of Ontario, Canada, presents data on the structure and function of the participating laboratories (including a comparison of the data for 1974 and 1980) and on the organization of the testing model (including selection of terminology, construction and use of the survey and assessment of responses). In 1980, of the 463 medical laboratories in Ontario, 91 of 222 hospital laboratories and 65 of 216 nonhospital laboratories were licensed in cytology. In that year, the 156 cytology laboratories processed 1.48 million cytology specimens, 92% of which were gynecologic. Hospital laboratories processed 87.5% of the nongynecologic cytology specimens and 30% of the gynecologic cytology specimens. These proportions have been virtually constant for several years. Between 1974 and 1980, there was a trend in Ontario to fewer laboratories processing less than 5,000 cytology specimens per annum. Subsequent papers in this series describe the results of the initial surveys in this program and a precision study to evaluate the consistency of reporting by individual laboratories.  相似文献   
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Plant growth promoting rhizobacteria were isolated and characterized from sandy soils in Pakistan. The role of the rhizobacteria, in association with plant growth regulators, was studied on the roots of wheat grown under water stressed conditions. The plant growth promoting rhizobacteria were characterized on the basis of colony morphology, biochemical traits and identified on the basis of 16S-rRNA gene sequencing which identified the selected isolates Planomicrobium chinense, Bacillus cereus and Pseudomonas fluorescens. Antibacterial and antifungal activities were determined. The fresh cultures (24 h old) of isolates were used to soak the seeds for 2–3 h prior to sowing. The growth regulators salicylic acid and putrescine were applied to the plant as foliar spray at three leaf stage. The plant growth promoting rhizobacteria produced exopolysaccharides that formed soil aggregation around roots of the plants and significantly enhanced water holding capacity of sandy soil. The relative water content (80%) of leaves and root fresh (80%) and dry weight (68%) were higher in plant growth promoting rhizobacteria inoculated plants. The nutrient content of rhizosphere soil of treated plants was also enhanced (Ca 35%, K 34%, Mg 52% and Na 42%) over stressed controls. Integrative use of effective plant growth promoting rhizobacteria in combination with salicylic acid appears to be an effective eco-friendly approach to increase drought tolerance in wheat plants to combat desertification.  相似文献   
189.
Astrocytes comprise approximately half of the volume of the adult mammalian brain and are the primary neuronal structural and trophic supportive elements. Astrocytes are organized into distinct nonoverlapping domains and extend elaborate and dense fine processes that interact intimately with synapses and cerebrovasculature. The recognition in the mid 1990s that astrocytes undergo elevations in intracellular calcium concentration following activation of G protein-coupled receptors by synaptically released neurotransmitters demonstrated not only that astrocytes display a form of excitability but also that astrocytes may be active participants in brain information processing. The roles that astrocytic calcium elevations play in neurophysiology and especially in modulation of neuronal activity have been intensely researched in recent years. This review will summarize the current understanding of the function of astrocytic calcium signaling in neurophysiological processes and discuss areas where the role of astrocytes remains controversial and will therefore benefit from further study.  相似文献   
190.

Background  

Rapid, robust and reversible induction of transgene expression would significantly facilitate cancer gene therapy as well as allow the in vivo functional study of newly discovered genes in tumor formation and progression. The popularity of the ecdysone inducible gene switch system has led us to investigate whether such a system can successfully regulate gene expression in a syngeneic tumor system in vivo.  相似文献   
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