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81.
Several subfamilies of the salmonid Hpa I short interspersed element (SINE) family were isolated from salmonid genomes and were sequenced. For each genomic locus that represented the subfamily, amplification by PCR of the orthologous loci in the 12 fish allowed us to determine the order of branching of the Pacific salmonid species. The deduced phylogeny suggests three evolutionary lines, namely, a line of chum salmon, pink salmon, and kokanee; a line of coho salmon and chinook salmon; and a line of steelhead trout. Our data also support a change in the phylogenetic assignment of steelhead trout from Salmo to Oncorhynchus. We present here an extensive phylogenetic tree constructed from an analysis of differential insertion of SINEs, and we propose that SINE insertion analysis is one of the best available methods for clarifying the order of divergence of closely related species.  相似文献   
82.
We report here on the ionic mechanisms underlying the depolarizing afterpotential (DAP) in neocortical pyramidal cells, with special interest in those underlying the burst afterdischarge. Injections of short depolarizing current pulses under whole-cell current clamp with a CsCl-based internal medium generated, in most pyramidal cells, a single action potential with a plateau phase (plateau-AP), followed by a slowly decaying DAP both in the absence and presence of TTX. Under voltage-clamp, the same cells displayed a slow tail current (tail-I) at the offset of depolarization. When intracellular free Ca2+ was chelated with 10 mm BAPTA or when extracellular Ca2+ was replaced with equimolar Ba2+, neither the slow DAP nor the slow tail-I was observed. Extracellular application of Co2+ or Cd2+ reduced Ca2+ currents and the slow tail-I. Cation substitution experiments revealed that the channel generating the slow tail-I was permeable to K+ and Cs+ more than to Na+ (PKPCs > PNa > PNMDGPTEA). The cationic slow tail-I was not reduced by applying antagonists of the metabotropic glutamate receptor (MCPG, 1 mm ) and the muscarinic receptor (atropine, 1–10 μm ). Thus, the slow DAP was produced by activation of the cationic channel whose gating is solely dependent on [Ca2+]i. An increase in [K+]o from 3 to 6 or 9 mm enhanced the slow DAP, and resulted in a generation of burst afterdischarges. An anticonvulsant, phenytoin (PT; 1–10 μm ) suppressed the slow DAP while enhancing the plateau-AP in the presence of TTX, most likely by blocking the cationic channel.  相似文献   
83.
A case of small fibrolamellar hepatocellular carcinoma (HCC) coexistent with a HCC of common type is herein reported. A 56-year-old man was diagnosed as having multi-nodular type HCC with liver cirrhosis. The serum alpha-fetoprotein (AFP) level was slightly increased. The patient underwent a partial caudate lobectomy and lateral segmentectomy. Histologically, both resected tumors were small HCCs measuring less than 2 cm in diameter. One was a fibrolamellar type located in the caudate lobe, while the other was the common type in the lateral segment of the liver. Positive immunohistochemical staining for AFP was observed in the tumor cells of the HCC of common type but was not observed in the fibrolamellar HCC. We also reviewed previously reported cases of fibrolamellar HCC in Japan, and discussed the clinicopathologic implications of this disease.  相似文献   
84.
Institute for Virus Research, Kyoto University, and Noguchi Memorial Research Institute in Ghana jointly isolated HIV-2 from a Ghanaian AIDS patient. Ghanaian HIV-2[GH-1] was similar in genomic organization to, but different in Restriction Enzyme Maps from the first isolated case, French LAV-2 (HIV-2ROD). This fact is significant in suggesting multiplicity of HIV-2 virus. HIV-2[GH-1] was different from LAV-2 in its antigenicity of envProtein. Sero-reactive patterns of 125 Ghanaians including 57 AIDS/ARC patients were analyzed using HIV-1, HIV-2, and SIVAGM as antigen. 4 groups were recognized. Group I was HIV-1 only positive; Group II, HIV-2-only positive; Group III, mixed HIV-1 and HIV-2 positive; Group IV reacted to gag protein of HIV-1, HIV-2 and SIVAGM but not to envProtein of any. 24 Ghanians were HIV-1 positive; 38 were HIV-2 positive. 19 out of 20 HIV-2-only positive patients were AIDS/ARC patients. Symptoms and route of infection from HIV-1 and HIV-2 AIDS seem to be similar but HIV-2 is weaker pathologically and in communicability. HIV positive patients were mostly found in the big city such as Accra among young women, especially prostitutes who were migratory "workers" in neighboring countries along the Ivory Coast. Sero-reactive patterns of Ghanaians with SIV as antigen had been known for some time to be different from those of Kenyans in the east coast and those of Gabonese. While KEnyan's antibody was high for HIV-1 and lower for SIVAGM, Ghanian's was higher for SIVAGM than HIV-1. Gabonese's was in between. With discovery of LAV-2 (HIV-2ROD) and Ghanian hybridization with its DNA probe Ghanaian's was found to have among other things VPX and VPR in common with HIV-2ROD.  相似文献   
85.
Although ileal conduit diversion is widely accepted in the treatment of the patients undergoing radical cystectomy, many patients would prefer other alternatives which allow continence. and urination through the urethra. We describe a new procedure in which a segment of detuburalized right colon is used as a continent reservoir. Eight patients, 7 after radical cystectomy for bladder cancer and one after total exenteration for rectal cancer, have undergone colon bladder replacement. New created bladder had a capacity of 300 to 600 ml. All patients could pass urine through the urethra but one is on self-catheterization. Five of the 8 patients had no residual urine. Three months after operations 4 were totally continent and 3 were satisfactorily dry during daytime but slightly enuretic. Excretory urography showed no abnormalities in their upper urinary tract. Considering the "quality of life' of a patient, this procedure can be an ideal option for selected patients.  相似文献   
86.
The body of a Japanese flounder (Paralichthys olivaceus) changes from a symmetrical to an asymmetrical form during metamorphosis. To obtain detailed information on the mechanisms of the migration of the right eye to the left side, soft and hard tissues in the head of larval flounders were examined using transmission electron microscopy (TEM). Retrorbital vesicles (Rvs) are pairs of sac-like structures under the eyes. It has been suggested that the asymmetrical development of Rvs, with the right (blind) one being bigger than the left, is the driving force behind eye migration. The present study revealed that the ultrastructure of the Rv sheath is quite similar to that of a lymphatic capillary. Thus, it is possible that the Rv is a part of the lymph system, and is probably related to the secondary vascular system in teleosts. If we assume that the Rv sheath has a high permeability to liquid, similar to lymphatic capillaries, it is not plausible that the active expansion of the Rv pushes the eyeball. On the other hand, the pseudomesial bar (Pb) is a bone that is unique to flounders and is present only on the right (blind) side. At the beginning of eye migration, an aggregation of fibroblast-like cells is observed in the dermis under the right eye, where the Pb will subsequently be formed. These cells have a well-developed rough endoplasmic reticulum (rER) and mitochondria, and are probably responsible for formation of the thick layers of collagen fibrils around them. Since it is unlikely that the active expansion of the Rv causes eye migration, the role played by the Pb and its rudiment becomes more significant in right eye migration in the Japanese flounder becomes more significant.  相似文献   
87.
The effects of chronic administration of phenytoin, a common anticonvulsive drug, on immune responses were studied in mice. Anti-keyhole limpet haemocyanin (KLH) IgE antibody response after KLH-immunization was enhanced in phenytoin-treated mice. Proliferative responses of spleen cells induced with KLH, concanavalin A (ConA), lipopolysaccharide and anti-CD3 antibody were reduced in phenytoin-treated mice. Accessory function of spleen adherent cells on ConA-induced T cell proliferative response was reduced in phenytoin-treated mice. KLH-induced IL-4 production of spleen cells was enhanced, while IFN-gamma production was reduced in phenytoin-treated mice. In addition, production of IL-1 alpha, but not IL-6 and IL-12 by spleen adherent cells from phenytoin-treated mice was reduced. Natural killer cell activity was reduced in phenytoin-treated mice. These results suggest that phenytoin treatment preferentially induces a Th2 type response. We also observed that plasma ACTH and corticosterone levels were increased in phenytoin-treated mice, and speculated that phenytoin might act directly and indirectly, through HPA axis activation, on the immune system to modulate Th1/Th2 balance.  相似文献   
88.
Adjuvant and antitumor activities of synthetic 6-O-"mycoloyl"-N-acetylmuramyl-L-alanyl-D-isoglutamine were examined. All the synthetic 6-O-corynomycoloyl-, 6-O-mocardomycoloyl-, and 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine were active as adjuvants for cell-mediated immune responses. However, 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine was less active as an adjuvant on circulating antibody formation. It was shown that pyrogenic activity of N-acetylmuramyldipeptide was reduced by 6-O-acylation with mycolic acid, but not with nocardomycolic or corynomycolic acid. Tumor-suppression activity was observed by the synthetic 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine by using transplantable tumor in syngenic mice.  相似文献   
89.
We present a method for handling nonscattering regions within diffusing domains. The method develops from an iterative radiosity-diffusion approach using Green's functions that was computationally slow. Here we present an improved implementation using a finite element method (FEM) that is direct. The fundamental idea is to introduce extra equations into the standard diffusion FEM to represent nondiffusive light propagation across a nonscattering region. By appropriate mesh node ordering the computational time is not much greater than for diffusion alone. We compare results from this method with those from a discrete ordinate transport code, and with Monte Carlo calculations. The agreement is very good, and, in addition, our scheme allows us to easily model time-dependent and frequency domain problems.  相似文献   
90.
K Yoneda  Y Okada 《Neuroscience》1989,28(2):401-407
The effects of anoxia and recovery on the neuronal transmission and the levels of high-energy phosphates such as ATP and phosphocreatine were studied using thin hippocampal slices from the guinea-pig. For the index of neuronal activity, postsynaptic field potentials were recorded in the CA3 and CA4 regions after electrical stimulation to the dentate gyrus during deprivation of oxygen and glucose from the perfusion medium at 36.5 degrees C. With deprivation of both oxygen and glucose from the medium, neuronal activity was abolished in 6-8 min. When the deprivation period was extended longer than 15 min, no recovery in the postsynaptic field potentials was observed. The concentrations of ATP and phosphocreatine in the slices decreased to 30-40% of original levels after 10 min deprivation of oxygen and glucose. ATP and phosphocreatine recovered to the original levels with the readmission of oxygen and glucose after 10 min anoxia, but the recovery of the ATP was worsened by the longer period of deprivation. Deprivation of oxygen only slowly decreased the amplitude of postsynaptic field potentials and blocked the neuronal activity after 70 min deprivation. The postsynaptic field potentials did not reappear after 180 min deprivation of oxygen. Even 120 min after deprivation of oxygen, the ATP and phosphocreatine levels were maintained at 60-70% of originals, whereas they both decreased to 30% after 150 min anoxia. The recovery of ATP even after 150 min anoxia was 64% and the recovery of phosphocreatine was over 100% even after 180 min anoxia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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