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1.
The immediate haemodynamic effects of peruvoside, a cardiac glycoside obtained from the Indian plant Thevetia neriifolia Juss, were studied in six patients with congestive heart failure. The drug was found to have an immediate and powerful positive inotropic and negative chronotropic effect, like ouabain, on the failing human heart. Oral peruvoside was also effective in the treatment of congestive heart failure when used on a short-term as well as a long-term basis. It therefore seems that peruvoside is a useful cardiac glycoside in the management of congestive heart failure in man as a quick-acting intravenous preparation. It is equally effective when used orally.  相似文献   
2.
Male Wistar rats weighing 150–200 g maintained under standard laboratory conditions and given Hindustan Lever Pellets and waterad libitum were exposed to –20°C for determination of the rate of fall of rectal temperature and survival time. The rate of fall of body temperature was significantly increased and the survival time was reduced, when animals were given an intraperitoneal injection of 1 ml/kg BW of CCl4 24 h but not 2 h earlier. Pre-treatment of the animals with 0.006 ml of garlic oil in a 2% solution of arachis oil for 3 days gave a significant protection to the animals against the CCl4-induced fall in cold tolerance. Administration of glucose orally 300 mg in 2 ml of saline eliminated the CCl4-induced fall in cold tolerance. The animals displayed a hypoglycemia 24 h, but not 2 h after injection of CCl4. CCl4-induced hypoglycemia was reduced by pre-treatment with garlic oil. The results indicate that the CCl4-induced reduction in cold tolerance is secondary to hypoglycemia and not due to the direct effect of CCl4 on the thermoregulatory mechanism in the CNS. The critical level of blood glucose below which the cold tolerance is reduced was found to be 76 mg/100 ml of blood.  相似文献   
3.
In an initial trial of glibenclamide in the treatment of maturity onset diabetes mellitus 28 patients were treated for up to one year and no toxic effects or side-effects were encountered. The hypoglycaemic potency of this drug is such that 5 mg. of glibenclamide corresponds to about 1,500 mg. of tolbutamide and 375 mg. of chlorpropamide.  相似文献   
4.
Neonatal rats, thyroidectomized at one day of age, received either no replacement therapy or daily subcutaneous injections of 100 μg/kg body weight of thyroxine (T4) or equal molar amounts of triiodothyroacetic acid (T3AC) from day 6 to day 26. Myelin lipid was isolated from the rat cerebrums and the cholesterol, cerebroside and total phospholipid content were determined. Cerebral myelin lipid weights were decreased in the neonatally thyroidectomized and T4 treated rats. The myelin lipid weights of the T3AC treated rats were not different from those treated with T4. The lipid composition remained unchanged in the T3AC, T4, and thyroidectomized groups when compared with the normal rats. These results indicate that T3AC and T4 administration have similar effects on CNS myelination in brains of neonatally thyroidectomized rats.  相似文献   
5.
Radiation-induced mutants of groundnut cv. Spanish Improved showing distinct morphological differences and the parent were screened for RAPD variability. The analysis revealed characteristic band differences among the 12 mutants and the parent. The polymorphic RAPD bands were dominant in the F1 and segregated in a Mendelian fashion in the F2. The RAPD technique brought out greater genome variability than RFLP.  相似文献   
6.
The commercialization of the biocatalytic desulfurization process does not seem to be realistic in the near future because of the low desulfurization rate of the known microorganisms. Hence, the future development will depend on either genetically modifying the currently available bacteria or identifying novel biodesulfurizers. In this study an in silico method to identify new biodesulfurizing microorganisms was adopted. By screening the available genomic databases, 13 novel desulfurizing microorganisms belonging to 12 genera were identified. Several of these could be of immense utility as they have both environment pollutant and industrial waste degrading capability.  相似文献   
7.
S C Bhatia  S Bhatia  S Rous 《Life sciences》1975,17(2):267-273
Livers of fed and fasted rats were perfused in situ in the presence and absence of 4.8 mM quinolinate, an in vivo inhibitor of phosphoenolpyruvate carboxykinase. An assay of the hepatic activities of serine dehydratase and serine pyruvate transaminase and a comparison of the in vivo incorporation of radioactivity from serine 3-14C and serine U-14C into blood glucose were also carried out in the above nutritional states. Our results demonstrate that gluconeogenesis from L-serine proceeds through two pathways. One, involving the reversal of the biosynthetic route of serine, bypasses conversion to pyruvate phosphoenolpyruvate and oxaloacetate and is not inhibited by quinolinate. This pathway appears to be the only one active in the fed state but produces a very insignificant amount of glucose. The other involves serine dehydratase mediated conversion of serine to pyruvate, is inhibited by quinolinate and becomes predominant during starvation.  相似文献   
8.
9.
A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa?1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm?2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array.  相似文献   
10.
Patient samples are unique and often irreplaceable. This allows biobanks to be a valuable source of material. The aim of this study was to assess the ability of Raman spectroscopy to screen for histologically confirmed cases of Cervical Intraepithelial neoplasia (CIN) using biobanked liquid based cytology (LBC) samples. Two temperatures for long term storage were assessed; 80°C and ?25°C. The utility of Raman spectroscopy for the detection of CIN was compared for fresh LBC samples and biobanked LBC samples. Two groups of samples were used for the study with one group associated with disease (CIN 3) and the other associated with no disease (cytology negative). The data indicates that samples stored at ?80°C are not suitable for assessment by Raman spectroscopy due to a lack of cellular material and the presence of cellular debris. However, the technology can be applied to fresh LBC samples and those stored at ?25°C and is, moreover, effective in the discrimination of negative samples from those where CIN 3 has been confirmed. Pooled fresh and biobanked samples are also amenable to the technology and achieve a similar sensitivity and specificity for CIN 3. This study demonstrates that cervical cytology samples stored within biobanks at temperatures that preclude cell lysis can act as a useful resource for Raman spectroscopy and will facilitate research and translational studies in this area.   相似文献   
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