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111.
Thiourea derivatives were identified as glyburide-reversible potassium channel openers through high-throughput screening. Based on these findings, a number of novel cyanoguanidines were designed and synthesized, which hyperpolarized human bladder K(ATP) channels. These agents are potent full agonists in relaxing electrically-stimulated pig bladder strips. The synthesis, SAR and biological properties of these agents are discussed.  相似文献   
112.
113.
This study investigated the effect of 5 day infusions of two structurally novel synthetic steroids, nivazol and cortivazol on blood pressure and in vivo indices of "glucocorticoid" and "mineralocorticoid" activity. Cortivazol at 24 mg/day raised mean arterial pressure (MAP) by 16 mmHg (P less than 0.001). This was associated with increased cardiac rate, and increased fasting plasma [glucose], polyuria and polydipsia a trilogy characteristic of glucocorticoid effect. Cortivazol had no consistent action on plasma [Na] or [K], but caused an initial transient urinary Na retention and raised urinary excretion of Na and K on days 3 and 4 of treatment. Nivazol at 24 mg/day raised MAP 10 mmHg (P less than 0.001), but cardiac rate was unchanged. This infusion was also associated with the glucocorticoid effects of increased fasting plasma [glucose] and increased urine volume. Plasma [K] fell from a control of 4.4 +/- 0.1 to 4.0 +/- 0.1 mmol/l (P less than 0.01) after 5 days of infusion. There was no significant effect of nivazol on urinary Na or K excretion. This study demonstrates that replacement of the 3-keto group, by a bulky phenylpyrazolo group fused to the A ring at position 2 and 3, does not diminish either pressor or glucocorticoid activity of steroids containing the typical 4-pregnene-3,20-dione nucleus and confirms that the 3 keto group is not essential for optimal glucocorticoid activity. It is the first demonstration of the pressor effect of these novel steroids.  相似文献   
114.
Infantile hypophosphatasia--linkage with the RH locus   总被引:8,自引:0,他引:8  
Linkage analysis of six nuclear families with infantile hypophosphatasia which were informative for the Rh blood group locus was performed. The maximum combined lod score was 4.76 with the recombinant distance (theta) of 0.04. These preliminary data provide evidence for linkage between the genes for infantile hypophosphatasia and the Rh blood group and provisionally assign the gene locus for infantile hypophosphatasia (designated HOPS) to chromosome 1p.  相似文献   
115.
Complete amino acid sequence of ovine salivary carbonic anhydrase   总被引:2,自引:0,他引:2  
The primary structure of the secreted carbonic anhydrase from ovine salivary glands has been determined by automated Edman sequence analysis of peptides generated by cyanogen bromide and tryptic cleavage of the protein and Staphylococcus aureus V8 protease, trypsin, and alpha-chymotrypsin subdigests of the large cyanogen bromide peptides. The enzyme is a single polypeptide chain comprising 307 amino acids and contains two apparent sites of carbohydrate attachment at Asn-50 and Asn-239. The protein contains two half-cystine residues at 25 and 207 which appear to form an intramolecular disulfide bond. Salivary carbonic anhydrase shows 33% sequence identity with the ovine cytoplasmic carbonic anhydrase II enzyme, with residues involved in the active site highly conserved. Compared to the cytoplasmic carbonic anhydrases, the secreted enzyme has a carboxyl-terminal extension of 45 amino acids. This is the first report of the complete amino acid sequence of a secreted carbonic anhydrase (CA VI).  相似文献   
116.
Taxonomy lies at the heart of species conservation, yet many large New Zealand orthopterans remain undescribed. Among New Zealand’s anostostomatid wētā, Hemiandrus (ground wētā) is the most speciose genus but also the most poorly characterised and thus most in need of taxonomic and ecological work. Here we redescribe H. maculifrons and describe two new species of ground wētā previously encompassed by the specific name Hemiandrus maculifrons: Hemiandrus luna sp. nov. and H. brucei sp. nov. We also describe a morphologically similar and related species, Hemiandrus nox sp. nov.

http://zoobank.org/urn:lsid:zoobank.org:pub:71EA0879-A2F9-46B2-A105-E97A9AB25061

http://zoobank.org/References/71EA0879-A2F9-46B2-A105-E97A9AB25061  相似文献   

117.
Characterized by proximal muscle weakness and wasting, limb-girdle muscular dystrophies (LGMDs) are a heterogeneous group of clinical disorders. Previous reports have documented either autosomal dominant or autosomal recessive modes of inheritance, with genetic linkage studies providing evidence for the existence of at least 12 distinct loci. Gene products have been identified for five genes responsible for autosomal recessive forms of the disorder. We performed a genome scan using pooled DNA from a large Hutterite kindred in which the affected members display a mild form of autosomal recessive LGMD. A total of 200 markers were used to screen pools of DNA from patients and their siblings. Linkage between the LGMD locus and D9S302 (maximum LOD score 5.99 at recombination fraction .03) was established. Since this marker resides within the chromosomal region known to harbor the gene causing Fukuyama congenital muscular dystrophy (FCMD), we expanded our investigations, to include additional markers in chromosome region 9q31-q34.1. Haplotype analysis revealed five recombinations that place the LGMD locus distal to the FCMD locus. The LGMD locus maps close to D9S934 (maximum multipoint LOD score 7.61) in a region that is estimated to be approximately 4.4 Mb (Genetic Location Database composite map). On the basis of an inferred ancestral recombination, the gene may lie in a 300-kb region between D9S302 and D9S934. Our results provide compelling evidence that yet another gene is involved in LGMD; we suggest that it be named "LGMD2H."  相似文献   
118.
In the intact, unstressed ovine fetus, both plasma immunoreactive adrenocorticotrophin (ACTH) and blood cortisol concentrations increased after 121 days gestation. The mean ACTH and cortisol concentrations in intact fetuses of 90-121, 122-135 and 136-144 days gestation were for ACTH 20.4 +/- 3.9 (50) (mean +/- SEM, n), 30.2 +/- 5.6 (26) and 56.0 +/- 6.3 pg/ml (37) respectively, and for cortisol 0.07 +/- 0.01 (24), 0.17 +/- 0.03 (21) and 0.64 +/- 0.13 microgram/100 ml (15), respectively. After 121 days ACTH and cortisol concentrations were correlated positively. Cortisol infused into intact or adrenalectomized fetuses and corticosterone infused into adrenalectomized fetuses suppressed fetal plasma ACTH concentrations. In summary, ACTH and cortisol increase concomitantly after 122 days, so that it is highly probable that ACTH is the trophic stimulus for fetal adrenal maturation. The suppression of ACTH by cortisol and corticosterone suggests that these are the natural feedback regulators. It is proposed that while the mechanism for cortisol feedback may exist early in gestation, it is not until after 121 days that feedback control of ACTH becomes evident and physiologically important.  相似文献   
119.
The present study examines the effect of [Sar1, Ile8] angiotensin II ([Sar1, Ile8] ANG II) on the blood clearance rate of [Val5] angiotensin II ([Val5] ANG II) in conscious, sodium-replete sheep. Animals were infused simultaneously with [Val5] ANG II and [Sar1, Ile8] ANG II at a rate of 42 nmol/h and 6 μmol/h respectively. Blood [Val5] ANG II was quantitatively determined with care taken in separating [Val5] ANG II from [Sar1, Ile8] ANG II prior to radioimmunoassay. The blood clearance rate of [Val5] ANG II calculated from infusion rate/blood concentration was significantly different before and during [Sar1, Ile8] ANG II infusion, being 141 ± 13 L/h (n = 12) and 95 ± 10 L/h (n = 12) respectively. Plasma renin concentration remained suppressed after the commencement of [Sar1, Ile8] ANG II infusion. In-vitro studies showed no significant decrease in the rate of degradation of [Val5] ANG II in blood in the presence of [Sar1, Ile8] ANG II. Possible interpretation of this reduction of blood clearance rate of [Val5] ANG II by 45 ± 15 L/h (n = 6) was discussed.  相似文献   
120.
The renal and cardiovascular effects of ANF infusion have been examined in separate series of experiments; in conscious instrumented sheep following either hemorrhage (10 mL/kg body weight) or removal of 500 mL of plasma by ultrafiltration. Renal arterial infusion of hANF (99-126) at 50 micrograms/h increased sodium excretion from 99 +/- 30 to 334 +/- 102 (p less than 0.05) in normal animals, and from 77 +/- 31 to 354 +/- 118 mumol/min in hemorrhaged animals. Similarly in sheep following ultrafiltration, cardiac output and stroke volume were reduced by intravenous infusion of ANF (100 micrograms/h), although these effects were less marked than those observed in normal animals. The rapid modulation of natriuretic responses to ANF observed in volume expanded animals is not seen in this model of acute volume depletion suggesting that the mechanism through which the renal response to ANF is modulated in low sodium or volume states is not simply the reverse of that which produces rapid enhancement of response following blood volume expansion.  相似文献   
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