ORAL PENICILLIN--A COMPARISON OF VARIOUS MODES OF ADMINISTRATION

A comparison of penicillin excretion when equivalent quantities of the drug are given orally or parenterally indicates that approximately 60 per cent. urinary excretion occurs after parenteral administration, whereas 14 per cent. urinary excretion occurs following oral ingestion. That destruction by gastric acidity is not primarily responsible for this difference is indicated by the fact that administration of penicillin directly into the duodenum does not greatly alter the amount of penicillin excretion. Evidence indicating that the majority of orally administered penicillin is destroyed by the body proper is discussed.     

IN VITRO EVIDENCE OF REGENERATION OF ACTIVE PENICILLIN FROM PENICILLIN ESTERS

It has been found that methyl and ethyl esters of penicillin may be hydrolyzed in vitro to yield 26 and 16 per cent. respectively of the theoretical bacteriostatically active penicillin.     

A METHOD OF PROLONGING THE ACTION OF PENICILLIN

(1) Single injections of penicillin in beeswax-peanut oil mixture will produce and maintain levels of penicillin in the blood for 7 or more hours. (2) These mixtures have maintained their potency at room, incubator and refrigerator temperatures for 30 to 62 days and show no signs of deterioration to date. (3) Eleven of twelve patients with gonorrhoea have been cured by a single injection of penicillin beeswaxpeanut oil mixture.     

The low therapeutic activity of penicillin K relative to that of penicillins F,G, and X,and its pharmacological basis

One hour after the injection into rabbits or man of penicillins F, G, K, and X at 0.6 mg./kg., blood levels of K were one-fourth to one-eleventh of those observed with the other penicillins, and K persisted at demonstrable levels for relatively short periods. In both rabbits and man the recovery of K in the urine averaged 30-35 per cent. This compares with an average recovery for F, G, and X of 74 per cent in rabbits and 91 per cent in man. In the treatment of experimental pneumococcal infections in white mice, an impure preparation of K was one-sixth as active as G and one-eighth as active as X. In the treatment of experimental streptococcal infections in white mice, a pure preparation of K was one-eleventh as active as G, and one-thirtieth as active as X. The above data suggest that penicillin K is inactivated in the body to a greater extent and more rapidly than either F, G, or X, resulting in a far lower therapeutic activity than would be anticipated from its bactericidal action in vitro. It seems clear that the amount of K in commercial penicillin should be minimized; and it would seem desirable to standardize impure mixtures of penicillins for therapeutic use by some method other than their bactericidal activity in vitro.     

生长促进素对吮乳仔猪生产性能及血液生化指标的影响

试验共选择15窝吮乳长白仔猪,观察高铜(250ppm)、复合抗菌素ISP(四环素110ppm、磺胺二甲嘧啶110ppm、青霉素55ppm)单独或配合使用,以及高铜与高钙、磷(Sa1.2％、P1.00％)配合使用对吮乳仔猪(15—60日龄)生产性能、血清各蛋白组分(α—、β—、r—球蛋白,清蛋白)和血清尿素N的影响。试验表明,高铜、高铜与高钙磷配合使用没有促生长作用;TSP组较对照提高9.0％(P>0.05);TSP与高铜合用获得了进一步的生长反应,日增重较对照组提高33.2％(P<0.01),腹泻显著地低于对照组(P<0.05);生长促进剂有降低血清球蛋白和尿素N的趋势。     

ISOLATION OF TRICHOMONAS VAGINALIS WITH PENICILLIN

Exposure of Trichomonas vaginalis in vaginal discharge for 60 hours to 5,000-10,000 units of penicillin in 10.0 ml of a medium containing cysteine (0.15 per cent.), peptone, liver infusion, maltose and human serum was adequate to destroy the associated bacteria. Seven strains were isolated from seven women without a failure. This technic widens the field of investigation by offering a means of obtaining additional strains of bacteria-free Trichomonas vaginalis for comparative study. Efforts to isolate Trichomonas vaginalis by such laborious methods as washing, micropipetting and migration have all failed to yield bacteria-free cultures at this and other laboratories. The adherence of bacteria to the trichomonads, which appear to have sticky surfaces, and the relatively slow speed with which these protozoa swim are probably in large measure responsible for failure. Further trials by these methods now seem unnecessary. In the cases reported above the success of the penicillin method may be attributed to several factors. Resistance of Trichomonas vaginalis to penicillin in the concentrations reported above, the absence from the specimens of vaginal discharge of bacteria resistant to penicillin in these same concentrations, and the destruction of bacteria adherent to the sticky surfaces of the trichomonads perhaps played a large part in assuring successful isolation of the protozoa.     

INTERACTION BETWEEN CRYSTALLINE PENICILLIN AND HUMAN PLASMA PROTEINS

Penicillin combines with human serum albumin, as demonstrated by dialysis experiments. Unlike the sulfonamfide-albumin complex, the penicillin-albumin possesses antibiotic activity. Such a complex can be freed of unbound penicillin by repeated precipitation at 50 per cent. alcohol and obtained as a dried powder. Mouse excretion studies indicated that the penicillin-albumin complex was excreted more slowly than the sodium salt of penicillin.     

A METHOD OF OBTAINING RENAL VENOUS BLOOD IN UNANESTHETIZED PERSONS WITH OBSERVATIONS ON THE EXTRACTION OF OXYGEN AND SODIUM PARA-AMINOHIPPURATE

Catheterization of the renal vein offers a safe and relatively simple method of obtaining blood as it leaves the kidney in the resting unanesthetized human subject. In preliminary observation on 8 subjects the renal arteriovenous oxygen difference varied from 1.9 to 2.8 volumes per cent., averaging 2.3 volumes per cent. Sodium para-amino hippurate, at low plasma levels, was 88 per cent. extracted during a single circulation through the kidney.     

THE INFLUENCE OF "FOLIC ACID" ON SPONTANEOUS BREAST CANCERS IN MICE

Complete regressions of spontaneous breast cancers in mice were observed in 38 among 89 animals (43 per cent.). The treatment consisted of daily intravenous injections of 5 micrograms of l. casei factor ("folic acid"). The treated animals lived longer than the controls, especially the healed mice. The incidence of the development of new tumors was decreased among the treated mice as compared with the controls.     

PENICILLIN IN IODIZED OIL FOR INSTILLATION INTO THE LUNGS

(1) A suspension of calcium penicillin in 40 per cent. iodized oil produces a stable mixture which has been instilled in the lungs of 12 patients without adverse effect and has maintained penicillin in the lung for a minimum of 24 hours, after a single instillation. (2) The penicillin iodized oil has maintained its potency for 60 days at ice box, room and 37 degrees C. temperatures.     

PROLONGING EFFECTIVE PENICILLIN ACTION

(1) Single injections of penicillin in saline administered intramuscularly with ice applications at the site of the injection produced and maintained bacteriostatic levels for six to twelve hours in nine out of ten patients, nine of whom were diagnosed as having gonorrhea and one urethritis with extracellular diplococci. (2) There was one failure, Subject No. 10, who received only 30,000 units. (3) Eight of the patients with gonorrhea and the one patient with urethritis were cured (bacteriologically and clinically) by this single intramuscular injection of penicillin.     

STUDIES ON THE FATE OF PLASMA PROTHROMBIN

The level of the plasma prothrombin in the circulating blood is decreased during its passage through the pulmonary capillaries. In 85 per cent. of samples, plasma prothrombin has been found to be less in the blood of the left ventricle than in that from the right ventricle. This difference averaged 10.6 per cent. and ranged from 4 to 19 per cent. In no instance was the level in the right ventricle lower than that in the left. In samples of blood taken from the arterial and venous supply of the head, liver, spleen, intestine, kidney and hind limbs, no significant difference in plasma prothrombin levels was found. A possible explanation of this role of the lung in the loss of plasma prothrombin is thought to be the production of blood platelets in this organ, as demonstrated by Howell and Donahue. Platelets, as they undergo disintegration, initiate the first stage of the clotting process by releasing thromboplastin, which, in the presence of calcium, changes prothrombin to thrombin.     

普通春玉米籽粒氨基酸含量、组成及影响因素的初步研究

本文在分析说明普通春玉米(中单2号、掖单13号)籽粒氨基酸含量及组成的基础上,阐明了必需氨基酸相对含量低(46.3%～47.4%),赖氨酸、蛋氨酸、苏氨酸相对含量低(7.3%～7.8%)是其蛋白质生物价低的主要原因;合理施用氮肥,特别是平衡施用化肥可大幅度提高氨基酸总量和必需氨基酸含量,但对氨基酸组成影响甚微;地膜的影响与配合化肥与否有关,配合化肥覆膜可提高氨基酸含量13.2%,对其组成无甚影响.无化肥覆膜降低氨基酸总量19.5%,但提高蛋白质品质灌水降低氨基酸总量7.6%,降低必需氨基酸含量9.5%,蛋白质品质有所降低.     

拔节水对春玉米氮磷钾吸收动态模型及肥料利用率影响的研究

通过田间试验结合化学分析和生物统计,查明了拔节水增产的营养基础包括显著地提高N、P、K在体内的浓度,促进各个生育时期N、P、K的累积吸收量,使N、P、K的最大吸收量分别提高11%,12%,6%;N、P、K最快吸收速率分别提高8%,25%,14%.最快吸收速率出现时间分别提前4d,5d,15d;使N、P、K的生产效率分别提高2.5%,1.9%,7.3%;使N、P、K化肥利用率分别提高5.0,5.0,12.7个百分点.     

ORAL ADMINISTRATION OF PENICILLIN

A convenient, practical and effective procedure of administering penicillin by mouth consists of mixing the drug with one tablespoonful of aluminum hydroxide. Substantially higher blood levels are obtained following a 50,000 and a 100,000 unit dose of penicillin with this method than after administration of the drug dissolved in water, either with or without previous ingestion of a mild antacid, such as aluminum hydroxide. Adsorption of penicillin on aluminum hydroxide appears to exert a local protective effect against that portion of gastric acid with which it comes into contact.     

拔节水对春玉米光合性能及产量形成的影响

通过田间试验,明确了丰水的1998年拔节水对春玉米光合性能及产量形成有以下影响平均叶面积指数和最大叶面积指数分别提高4%和12%,总光合势增长6%;全期干物质最快累积速度479kg/hm2@d,提高12%,生物产量提高13%;籽粒平均增长速度2.84g/株@d,增产14.5%,单株籽粒重156g,增长12.4%;在籽粒的干物质来源中,开花后合成累积部分占46.5%,提高9.6个百分点;干物质在叶、茎、苞叶等器官的移动率,以及收获指数都有所降低.     

日本落叶松、杂种落叶松嫩枝全光喷雾扦插的研究

利用日本落叶松优树子代2.5年生的幼树、50.5年生优树及9.5年生杂种落叶松优良个体做为采条母树,以河沙、锯末、蛭石为基质,借用长臂旋转扫描喷雾装置,在全光喷雾条件下,扦插半木质化的嫩枝获得成功。2.5年生幼树条扦插生根率达95％以上(6月20日扦插),17个9.5年生杂种落叶松优株条扦插(7月20日),平均生根率,河沙基质为74.31％,锯末基质为68.60％,蛭石基质为51.90％,生根率最高的系达到96.20％,生根率超过70％以上的系占41.18％。扦插基质对生根的影响作用,以河沙为最好。50.5年生的成龄母树条扦插,幼化的干萌条和嫁接后的幼树条扦插,都比没有经过幼化处理的插穗提高生根率。生根素IBA、ABT处理2.5年生幼树条,7月20日扦插,对生根速度有作用,生根素浓度,50ppm比100ppm好,处理50.5年生成龄母树条100ppm比50ppm好。     

地膜覆盖对春玉米籽粒建成和品质形成影响的研究

以掖单13为材料,系统地研究了覆膜与露地条件下春玉米籽粒建成与品质形成规律.结果表明二者在变化趋势上相同,但在籽粒建成与营养品质形成的实质上有显著差异.地膜覆盖可显著地提高籽粒灌浆速率,百粒籽粒干重日平均增长0.6g,比露地提高20%,最大增长速率1.24g/100粒@d,比露地提高5%.成熟期,使籽粒百粒重(干)增长10.7%,可显著提高籽粒脱水速度,降低籽粒后期含水率.覆膜能显著地提高籽粒淀粉、粗脂肪、粗蛋白质、还原糖、水溶性糖、蔗糖含量,分别比露地平均高出1.89,0.18,4.77,0.39,1.7,1.3个百分点.地膜覆盖不仅是春玉米的增产措施,也是全面提高春玉米品质的栽培技术.     

SEDIMENTATION OF POLIOMYELITIS VIRUS BY CENTRIFUGATION

A technic is described whereby poliomyelitis virus may be sedimented by centrifugation for four hours at 18,000 r.p.m. Virus has been recovered quantitatively in the sediment from a 20 per cent., but not a 1 per cent., saline suspension. The addition of 10 per cent. normal serum results in quantitative recovery from a 1 per cent. suspension. Virus has been recovered by intracerebral inoculation from two of four human stools tested by the method described.     

长豇豆农艺性状对产量和品质的关联性研究

用相关及通径分析研究了构成长豇豆产量各性状间及其与蛋白质间的关系,结果表明,单株结荚数对产量的贡献最大。其它与产量密切相关的性状(侧蔓数、第一侧蔓节位、采收期),均以较大的间接效应,通过单株结荚数而作用于产量的。因此,单株结荚数是决定产量至关重要的性状。 试验还表明,长豇豆主蔓结荚重量占全株产量的70～90％。荚肉的重量是构成豆荚重量的主要组成部分,占荚重的80％以上。 蛋白质含量与豆荚长度是显著正相关,与单荚重呈极显著正相关。荚长对蛋白质有较大的直接效应,而单荚重是通过荚长的间接效应较大而作用于蛋白质的。因此,荚长是决定蛋白质含量高低的主要性状。且荚长的广义遗传力达93.6％,选择效果好。 因此,在长豇豆选育工作中,注意选择单株结荚数目多,荚肉厚、荚长度长的单株或株系,有利于提高对产量和蛋白质性状的选择效果,可能育成高产量高蛋白的新品种。