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961.
One hundred and twenty-eight patients with iron deficiency anemia were treated with a new intramuscular iron preparation, iron-sorbitol-citric acid. One group of 10 patients received a total of 1000 mg. each of elemental iron intramuscularly. All obtained a rise in hemoglobin of over 2.1 g. %, an elevation of serum iron, and a reticulocyte response over 6%. A second larger group of subjects consisted of 113 prenatal and five gynecologic patients; these received an average total dose of 1050 mg. and 1020 mg., respectively, and the average increase in hemoglobin ranged from 1.6 g. % to 2.5 g. %.None of the patients developed significant side effects after injection or permanent staining at the site of injection. Three patients experienced a transient ache at the injection site, and three developed local urticaria-like reactions lasting 24 hours.This new preparation appears to be a safe and clinically effective therapeutic agent in situations in which parenteral iron is indicated.  相似文献   
962.
The armored catfish Pterygoplichthys pardalis tolerates environmental hypercarbia, high partial pressures of CO2 (\(P_{{{\text{CO}}_{ 2} }}\)), by preferentially protecting intracellular pH (pHi) in the face of extracellular acidosis. This response is associated with ionic changes which may disrupt contractility in cardiac muscle, and it is not known whether acclimation to hypercarbia provides protection against these changes. We studied the influence of different \(P_{{{\text{CO}}_{ 2} }}\) acclimation histories on cardiac muscle function using isometrically contracting ventricular strip preparations. Fish were held for >4 months at 21 mmHg \(P_{{{\text{CO}}_{ 2} }}\) and then exposed to normocarbia (6 mmHg \(P_{{{\text{CO}}_{ 2} }}\)) for either 15 h or 5–6 days. Acclimation to chronic hypercarbia eliminated the negative inotropic effects of in vitro hypercarbia, decreased extracellular Ca2+ sensitivity, and reduced maximum pacing frequency in ventricular strip preparations. Fish acclimated to chronic hypercarbia also exhibited hepatic glycogen and plasma glucose accumulation, and lower plasma lactate levels compared to fish acclimated to normocarbia for 5–6 days. We suggest chronic hypercarbia may induce cardiac remodeling to protect contractility and reduce the energetic demands of pHi regulation. The activation of HCO3 ? synthesis pathways may decrease glucose utilization and enhance carbohydrate stores, potentially providing protection against hypoxia, a stressor frequently encountered in conjunction with hypercarbia in the Amazon.  相似文献   
963.
Summary Growth of choriocarcinoma cells in the presence of 5-bromo-2′-deoxyuridine (BrdUrd) results in a 30- to 40-fold increase in alkaline phosphatase activity. The effect of BrdUrd is specific for phosphatase with an alkaline pH optimum. The induction by BrdUrd is probably not due to the production of an altered enzyme, since the induced enzyme resembles the basal enzyme in thermal denaturation and kinetic properties. Enzyme induction can be prevented by thymidine but not by deoxycytidine or deoxyuridine. The induction of alkaline phosphatase appears to require incorporation of the BrdUrd into cellular DNA. The presence of BrdUrd in the growth medium is not necessary for alkaline phosphatase induction in proliferating cells containing: BrdUrd-substituted genomes. However, enzyme induction and maintenance of the induced levels of alkaline phosphatase in nonproliferating cells containing BrdUrd-substituted DNA requires the presence of the analogues in the medium. The induction of alkaline phosphatase by BrdUrd in probably an indirect process.  相似文献   
964.
This is the fourth paper in a series on the distribution of blood groups among Indians of South America. It reports the findings on the Indians of Chile and the Polynesians of Chile's Easter Island. Blood specimens were procured from the following putatively pure Indians and unmixed Polynesians: 44 Alacaluf of Puerto Eden, Isla Wellington, 141 Mapuche (Araucanian) of Lonquimay, Malleco Province, 80 Atacameños of Antofagasta Province, and 45 Polynesians of Easter Island. These 310 samples were tested for blood factors in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, K-k, Lewis, Duffy, Kidd and Diego systems, and for the Wright (Wra) agglutinogen. Serum samples were tested for haptoglobins and transferrins. Hemolysates prepared from the blood clots were tested for hemoglobin types. The results are presented as phenotype incidences and calculated gene frequencies in appropriate tables. Locations of the populations from which blood samples were procured are shown on two maps. The high frequencies for the O gene usually reported for South American Indians obtain in putatively pure Chilean Indians but A1 is high in Easter Island Polynesians. In both Indians and Polynesians M, s, R1 (CDe), R2 (cDE), Lub, k, LeH, and Fya gene frequencies are high and B, N, S, Mia, Vw, Rº (cDe), r (cde), Lua, K, Le1, Fyb, and Wra (Ca) are low or absent. The Diego (Di) gene is present in the Mapuche and Atacameños but absent in the Alacaluf and Polynesians. Hp1 gene frequencies were determined only in the Alacaluf and Atacameños, in which they are 0.48 and 0.67 respectively. Transferrins were determined for the Alacaluf and Atacameños Indians and all were classified as Tf C. All Chilean Indian and Polynesian specimens were tested electrophoretically for hemoglobin types and all contained only hemoglobin (A) as a major component.  相似文献   
965.
966.
967.
Aromatic and heterocyclic aldehydes may be produced by the mandelate pathway of Pseudomonas putida ATCC 12633 via the biotransformation of benzoyl formate and substrate analogues. Under optimised biotransformation conditions (37 °C, pH 5.4) and with benzoyl formate as a substrate, benzaldehyde may be accumulated with yields above 85%. Benzaldehyde is toxic to P. putida ATCC 12633; levels above 0.5 g/l (5 mM) reduce the biotransformation activity. Total activity loss occurs at an aldehyde concentration of 2.1 g/l (20 mM). To overcome this limitation, the rapid removal of the aldehyde is desirable via in situ product removal. The biotransformation of benzoyl formate (working volume 1 l) without in situ product removal accumulates 2.1 g/l benzaldehyde. Benzaldehyde removal by gas stripping produces a total of 3.5 g/l before inhibition. However, the most efficient method is solid-phase adsorption using activated charcoal as the sorbant, this allows the production of over 4.1 g/l benzaldehyde. Addition of bisulphite as a complexing agent causes inhibition of the biotransformation and bisulphite is therefore is not suitable for in situ product removal. Received: 16 March 1998 / Received revision: 20 May 1998 / Accepted: 21 May 1998  相似文献   
968.
Potentially poplars and willows may be used for the in situ decontamination of soils polluted with Cd, such as pasturelands fertilised with Cd-rich superphosphate fertiliser. Poplar (Kawa and Argyle) and willow (Tangoio) clones were grown in soils containing a range (0.6–60.6 μg g−1 dry soil) of Cd concentrations. The willow clone accumulated significantly more Cd (9–167 μg g−1 dry matter) than the two poplar clones (6–75 μg g−1), which themselves were not significantly different. Poplar trees (Beaupré) sampled in situ from a contaminated site near the town of Auby, Northern France, were also found to accumulate significant quantities (up to 209 μg g−1) of Cd. The addition of chelating agents (0.5 and 2 g kg−1 EDTA, 0.5 g kg−1 DTPA and 0.5 g kg−1NTA) to poplar (Kawa) clones caused a temporary increase in uptake of Cd. However, two of the chelating agents (2 g kg−1 EDTA and 0.5 g kg−1 NTA) also resulted in a significant reduction in growth, as well as abscission of leaves. If the results obtained in these pot experiments can be realised in the field, then a single crop of willows could remove over 100 years worth of fertiliser-induced Cd contamination from pasturelands. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
969.
Birds Do It. Bees Do It. So Why Not Single Women and Lesbians?   总被引:2,自引:0,他引:2  
Bambi E.S. Robinson 《Bioethics》1997,11(3&4):217-227
Infertile couples have come to take assisted reproductive technologies (ART) for granted. An increasing number of single women and lesbian couples also desire to have children and turn to ART, especially donor insemination, to fulfill this desire. While most married couples find that access to ART is limited primarily by the ability to pay, for single women and lesbian couples, the story may be much different. In the United States, they may find that doctors and infertility clinics view their desires as immoral and refuse to accept them as patients, although other doctors and clinics readily accept them. In most other countries, however, it is against the law for single women and lesbian couples to make use of ART, including donor insemination.
In this paper I will argue that marital status and sexual orientation should not serve as a barrier to accessing the world of reproductive medicine. I will base this conclusion on two arguments. First, that justice requires that we treat like cases alike. Just as we would not accept or reject patients for cardiac rehabilitation programs based on factors such as a history of poor eating habits, so too we should not look at nonmedical factors such as marital status when deciding whether to treat infertility. For the second justification for the conclusion of equal access to ART, I will examine the concept of the family. I will argue that it is morally acceptable for single women and lesbian couples to have children and to head families.  相似文献   
970.
Genetic Variances in Open Pollinated Varieties of Corn   总被引:1,自引:0,他引:1       下载免费PDF全文
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