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1.
Between 1976 and 1984, 136 patients with portal hypertension due to extrahepatic obstruction were operated on. Twenty two patients had emergency and 114 elective operations. The operative mortality was 9% and 1%, respectively. Altogether 117 patients (86%) were followed up for from two to 10 years: 17 rebled, none developed encephalopathy or sepsis after splenectomy, and 90% and 75% were alive at five and 10 years respectively. Unlike endoscopic sclerotherapy and treatment with propranolol, operative treatment of variceal bleeding can usually be completed during one admission and carries a low mortality and a fairly low morbidity. Operation seems to be the best form of treatment for poor patients living far from medical facilities in developing countries and may be the treatment of choice in developed countries as well.  相似文献   
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A method to obtain plants from embryogenic callus of Brassica nigra and protoplasts of hypocotyl expiants is described. Callus was initiated on Murashige and Skoog medium containing kinetin (kn) and 2,4-dichlorophenoxy acetic acid (2,4-D). Lowering of auxin induced embryo formation. Supplementation with gibberellic acid (GA3) enhanced embryogenic response tenfold. Passage through liquid medium devoid of growth regulators was essential for the growth of embryos. Secondary embryos were produced on transfer to solid basal medium. Embryogenic callus retained its morphogenic ability even after 12 subcultures. Both primary and secondary embryos produced fertile plants. Hypocotyl-derived protoplasts were also regenerated to plants following the same protocol. The survival of plants on transfer to soil was about 80%. The seeds from plants derived from callus and protoplasts were viable.Abbreviations 2,4-D 2,4-dichlorophenoxy acetic acid - NAA naphthalene acetic acid - IAA indole acetic acid - kn kinetin - GA3 gibberellic acid  相似文献   
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The effect of interferon on the expression of the vesicular stomatitis virus glycoprotein G gene was examined in simian COS cells transfected with the expression vector pSVGL containing the G gene under the control of the SV40 late promoter. When COS cells were treated with interferon 24 h after transfection, the synthesis of vesicular stomatitis virus G protein was inhibited by about 80% as compared to that in untreated controls. By contrast, under the same conditions, neither the plasmid copy number nor the G gene mRNA levels were detectably affected by interferon treatment. Likewise, the synthesis of simian virus 40 large T-antigen was not inhibited by interferon treatment of transfected COS cells even though the synthesis of vesicular stomatitis virus G protein was markedly inhibited. The residual G protein synthesized in transfected, interferon-treated COS cells appeared to be normally glycosylated.  相似文献   
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Summary Inhibitory effect of potassium chloride on nitrification of ammonium sulfate and urea in acid, neutral and calcareous soils was observed in an incubation study. In acidic soil, NO 3 –N production in soil treated with urea was retarded by addition of KCl. NO 3 –N concentration was much less even in comparison to control where ammonium sulfate and KCl were added together which might be due to cumulative effect of Cl and SO 4 –2 ions. In neutral and calcareous soils, nitrification inhibition was less conspicuous.  相似文献   
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During the period of COVID-19, the occurrences of mucormycosis in immunocompromised patients have increased significantly. Mucormycosis (black fungus) is a rare and rapidly progressing fungal infection associated with high mortality and morbidity in India as well as globally. The causative agents for this infection are collectively called mucoromycetes which are the members of the order Mucorales. The diagnosis of the infection needs to be performed as soon as the occurrence of clinical symptoms which differs with types of Mucorales infection. Imaging techniques magnetic resonance imaging or computed tomography scan, culture testing, and microscopy are the approaches for the diagnosis. After the diagnosis of the infection is confirmed, rapid action is needed for the treatment in the form of antifungal therapy or surgery depending upon the severity of the infection. Delaying in treatment declines the chances of survival. In antifungal therapy, there are two approaches first-line therapy (monotherapy) and combination therapy. Amphotericin B ( 1 ) and isavuconazole ( 2 ) are the drugs of choice for first-line therapy in the treatment of mucormycosis. Salvage therapy with posaconazole ( 3 ) and deferasirox ( 4 ) is another approach for patients who are not responsible for any other therapy. Adjunctive therapy is also used in the treatment of mucormycosis along with first-line therapy, which involves hyperbaric oxygen and cytokine therapy. There are some drugs like VT-1161 ( 5 ) and APX001A ( 6 ), Colistin, SCH 42427, and PC1244 that are under clinical trials. Despite all these approaches, none can be 100% successful in giving results. Therefore, new medications with favorable or little side effects are required for the treatment of mucormycosis.  相似文献   
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The difference spectroscopy technique has been utilized to investigate the temperature-induced spectral changes in mesophyll and bundle sheath chloroplasts of maize ( Zea mays L. cv. Ganga-5) in order to assess the role of different pigment-protein complexes in the manifestation of temperature effect on the chloroplast membranes. Cooling and heating of both mesophyll and bundle sheath chloroplasts resulted in absorbance difference (AA) bands at similar wavelengths but the degree of absorb-ance changes were significantly higher in bundle sheath chloroplasts. For example, upon cooling to 7-8°C, positive AA bands were observed at 440, 490 and 680 nm in mesophyll chloroplasts and at 440, 495–500 and 680 nm in bundle sheath chloroplasts but the absorbance change at 680 nm was ca 2% in mesophyll chloroplasts, whereas it was ca 5% in bundle sheath chloroplasts, which have a lower content of light-harvesting pigment-protein complex. The role of chlorophyll-protein complexes was further investigated by monitoring the temperature-induced spectral changes of mesophyll and bundle sheath chloroplasts isolated from lincomycin-treated maize plants where lincomycin selectively inhibits the biosynthesis of specific chlorophyll-protein complexes. Results indicated that depletion of certain pigment-protein complexes in mesophyll chloroplasts made them more susceptible (a ca 4% vs ca 2% absorbance change upon cooling and a ca 6% vs ca 4% absorbance change upon heating) and less tolerant to temperature variation (a 76% vs 39% reversibility during ambient→Cooling→ambient temperature cycle). The data indicate that pigment-protein complexes play a significant role in protecting the chloroplast membranes against temperature variation.  相似文献   
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Baculoviruses have enormous potential for use as biopesticides to control insect pest populations without the adverse environmental effects posed by the widespread use of chemical pesticides. However, continuous baculovirus production is susceptible to DNA mutation and the subsequent production of defective interfering particles (DIPs). The amount of DIPs produced and their genome length distribution are of great interest not only for baculoviruses but for many other DNA and RNA viruses. In this study, we elucidate this aspect of virus replication using baculovirus as an example system and both experimental and modeling studies. The existing mathematical models for the virus replication process consider DIPs as a lumped quantity and do not consider the genome length distribution of the DIPs. In this study, a detailed population balance model for the cell‐virus culture is presented, which predicts the genome length distribution of the DIP population along with their relative proportion. The model is simulated using the kinetic Monte Carlo algorithm, and the results agree well with the experimental results. Using this model, a practical strategy to maintain the DIP fraction to near to its maximum and minimum limits has been demonstrated.  相似文献   
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