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901.
We evaluated the method of active specific intralymphatic immunization to treat cancer in 32 patients with various tumor types as part of a broad-based phase I-II evaluation and describe the results of 3 sequential series. In series 1, the patients (n = 13) received 2 or more injections of autologous, cryopreserved, irradiated tumor cells directly into the lymphatic system through the cannulation of a dorsal pedal lymphatic channel. In series 2, the patients (n = 7) received low-dose cyclophosphamide, 300 mg per m2, 3 days before the autologous cell vaccine was administered. Series 3 (12 patients) was similar to series 2 except that the tumor cells were treated with cholesteryl hemisuccinate immediately before irradiation. Patients received from 2 to 6 injections of cells, depending on availability, at 2-week intervals. In all, 91 treatments are evaluated in this study. Clinical responses occurred in 7 of the 32 patients and were seen in all 3 series with about the same frequency. These responses occurred in cases of melanoma, lung cancer, colon cancer, and sarcoma. Regressions occurred in both visceral and subcutaneous sites. There was little toxicity, the chief side effect being local discomfort or inflammation. This experience indicates that active specific intralymphatic immunotherapy is safe, produces antitumor effects, and requires more investigation to increase the frequency and duration of observable tumor regression.  相似文献   
902.
The ability of lithium to interfere with phosphoinositide metabolism in rat cerebral cortex slices has been examined by monitoring the accumulation of CMP-phosphatidate (CMP-PtdOH) and the reduction in Ins(1,4,5)P3 and Ins(1,3,4,5)P4 levels. A small accumulation of [14C]CMP-PtdOH was seen in slices prelabelled with [14C]cytidine and stimulated with carbachol (1 mM) or Li+ (1 mM). However, simultaneous addition of both agents for 30 min produced a 22-fold accumulation, with Li+ producing a half-maximal effect at a concentration of 0.61 +/- 0.19 mM. Kinetic studies revealed that the effects of carbachol and Li+ on CMP-PtdOH accumulation occurred with no initial lag apparent under these conditions and that preincubation with myo-inositol (10 or 30 mM) dramatically attenuated CMP-PtdOH accumulation. myo-Inositol could also attenuate the rate of accumulation of CMP-PtdOH when added 20 min after carbachol and Li+; these effects were not observed when equimolar concentrations of scyllo-inositol were added. Use of specific radioreceptor assays allowed the mass accumulations of Ins(1,4,5)P3 and Ins(1,3,4,5)P4 to be monitored. Following a lag of 5-10 min, Li+ resulted in a marked reduction in the accumulation of both inositol polyphosphates resulting from muscarinic-cholinergic stimulation. Preincubation of cerebral cortex slices with myo- (but not scyllo-) inositol delayed, but did not prevent, the reduction in the accumulation of Ins(1,4,5)P3 or Ins(1,3,4,5)P4. The results suggest that cerebral cortex, at least in vitro, is very sensitive to myo-inositol depletion under conditions of muscarinic receptor stimulation. The relationship of such depletion to the generation of inositol polyphosphate second messengers is discussed.  相似文献   
903.
Brain type II Ca2+/calmodulin-dependent protein kinase was found to phoshorylate smooth muscle myosin, incorporating maximally 2 mol of phosphoryl per mol of myosin, exclusively on the 20,000 dalton light chain subunit. After maximal phosphorylation of myosin or the isolated 20,000 dalton light chain subunit by myosin light chain kinase, the addition of type II Ca2+/calmodulin-dependent protein kinase led to no further incorporation indicating the two kinases phosphorylated a common site. This conclusion was supported by two dimensional mapping of tryptic digests of myosin phosphorylated by the two kinases. By phosphoamino acid analysis the phosphorylated residue was identified as a serine. The phosphorylation by type II Ca 2+/calmodulin-dependent protein kinase of myosin resulted in enhancement of its actin-activated Mg2+-ATPase activity. Taken together, these data strongly support the conclusion that type II Ca2+/calmodulin-dependent protein kinase phosphorylates the same amino acid residue on the 20,000 dalton light chain subunit of smooth muscle myosin as is phosphorylated by myosin light chain kinase and suggest an alternative mechanism for the regulation of actin-myosin interaction.Abbreviations SDS-PAGE Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis - EGTA Ethylene Glycol Bis (-amino-ethyl ether)-N,N,N,N-Tetraacetic Acid - DTT Dithiothreitol - LC20 Gizzard Smooth Muscle Phosphorylatable 20 kDa Myosin Light Chain - LC17 Gizzard Smooth Muscle, 17 kDa Myosin Light Chain - H Chain Gizzard Smooth Muscle 200 kDa Myosin Heavy Chain - TPCK L-1-Tosylamido-2-Phenylethyl Chloromethyl Ketone - MOPS 3-(N-morpholino) Propanesulfonic Acid  相似文献   
904.
A cDNA clone of the beta subunit of human fibronectin receptor (FNRB) detects two different polymorphic loci: (a) a codominant system previously mapped to the pericentromeric region of chromosome 10, the site of the functional FNRB gene; and (b) a dominant system not linked to the first one or to any chromosome 10 marker tested. This second polymorphism is characterized by the presence or absence of a band (or a set of bands). We have used linkage analysis and biotin-labeled in situ hybridization to map this dominant polymorphism to the short arm of chromosome 19; we hypothesize that it may be due to the insertion of part of the cDNA from the chromosome 10 gene into chromosome 19. This "insertion" is polymorphic in all populations studied.  相似文献   
905.
In a randomized controlled trial 50 patients with duodenal ulcer treated by proximal gastric vagotomy (P.G.V.) without drainage were compared with 50 who underwent selective vagotomy and gastrojejunostomy. The clinical results were assessed in 99 patients one to four years after operation. Patients who had undergone P.G.V. had significantly less dumping, nausea, and bile vomiting and fared better in their overall clinical grading. The postoperative Visick grading of the 50 patients with P.G.V. was similar to that of 56 controls with no known gastrointestinal disease who had not undergone operation. The results obtained in the patients who had had P.G.V. without drainage were compared with those of a further group of 24 patients subjected of P.G.V. with gastrojejunostomy, and the better results obtained in the former group were thought to be due to elimination of the drainage procedure. The average follow-up period of the trial was just over two years, but there were no indications that the recurrent ulceration rate after P.G.V. would be any higher than after other types of vagotomy and drainage.  相似文献   
906.
Comparative studies on nervous systems, though infrequently undertaken for the purpose of comparison, have yielded some important generalities about the formats of nervous networks, and about the cell biology of certain neural types. In the first category, it is clear that convergent evolutionary processes arrived at very similar networks to accomplish reciprocal and lateral inhibition, and load-compensation in "resistance reflexes." A newer general network format is described, command-derived inhibition, in which the central nervous elements controlling a rapid movement deliver presynaptic inhibition to the terminals of sensory neurons that carry reafferent excitation from the movement. It is argued that such circuits occur in several groups of animals, and that they include as a special class the efferent inhibitory neurons innervating acoustico-lateralis receptors in vertebrates. The properties of circuit elements that now seem to constitute useful generalizations include size principle (the inverse relationship between size and excitability in a variety of neurons), and the late differentiation of sensory neurons, failure to decussate, and their inability to mediate inhibition. Many other generalities have emerged, only to fall; one conclusion from such searches is that many supposedly "basic" properties of cell types or neural circuits are in fact not phylogenetically conservative, however much the physiologist may expect them to be.  相似文献   
907.
908.
909.
A method previously described for the use of bentonite in the isolation of the nucleic acids from two gram-positive organisms was applied to the isolation of the nucleic acids from two strains of Clostridium welchii. The nucleic acids were separated from polysaccharides by the fractional precipitation of their cetyltrimethyl-ammonium salts from sodium chloride solution, and the base composition of the nucleic acids was determined. One strain of C. welchii investigated (NCTC 10578) was shown to produce considerable quantities of an acidic and also a weakly acidic or neutral polysaccharide; the other strain (ATCC 10543) gave very small quantities of the latter but none of the former polysaccharide. The monosaccharide composition of these polysaccharides was determined and the acidic polysaccharide was shown to resemble dermatan sulfate.  相似文献   
910.
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