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1.
Mice given daily i.p. injections of immunoglobulins against ovine LH on Days 3-7 of pregnancy were devoid of implantation sites on Day 8 whereas mice treated with antibodies to hCG had embryos of normal number and appearance on Day 8. These antibody treatments reduced the mean +/- s.d. serum progesterone concentrations from 65.4 +/- 15.3 ng/ml (control globulins) to 8.6 +/- 4.9 ng/ml (anti-LH) and 9.2 +/- 3.1 ng/ml (anti-hCG) on Day 8 and had no differential effect on serum oestrogen levels on Day 4. However, the mice treated with anti-hCG did not litter; resorption of the embryos took place between Days 10 and 14 of pregnancy. Indirect immunofluorescence and quantitative immunoenzymic assays showed the presence of anti-ovine LH and anti-hCG reacting antigens in the mouse feto-placental unit. On Day 6, the values of reacting antigens (mean +/- s.d. absorbance units/10 micron section of embryo) were 0.050 +/- 0.002 with control globulins, 0.059 +/- 0.002 with anti-hCG-Ig and 0.196 +/- 0.018 with anti-LH-Ig; the corresponding values on Day 12 were 0.075 +/- 0.009, 0.402 +/- 0.02 and 0.416 +/- 0.015. The quantitative disposition of the reacting antigens to the two types of anti-gonadotrophins seems to bear a temporal relationship to their respective antifertility action. The pregnancy terminating action of immunoglobulins to ovine LH (Days 6, 7 & 8) and hCG (Days 8, 9 & 10) was counteracted by administration of 2 mg medroxyprogesterone acetate on Days 6, 9 and 12, indicating the importance of progesterone in the maintenance of pregnancy in the mouse.  相似文献   
2.
A leaf tip hooded mutant was isolated in the progenies of the irradiated seeds of a commercial tobacco variety, namely Delcrest. The mutant character was determined as monogenic recessive. Along with leaf tip hooding, certain other characters such as increase in size of leaves, number and clasping arrangement of leaves on stem, and delayed flowering, were found to be closely associated and this was attributed to the pleiotropic effect of the leaf tip hooding gene.  相似文献   
3.
A new reaction of selenomethionine with o-benzoquinone is described. This reaction can be used to distinguish between methionine and selenomethionine.  相似文献   
4.
Abstract

Concentrations of heavy metals (Cd, Co, Cr, Cu and Fe) in surface sediments and their partitioning behaviour between exchangeable, reducible (Fe-Mn oxide bound) and organic/residual phases of the sediments in a typical backwater system of Kerala, viz. the southern upstream part of Cochin Estuarine System (South India), have been studied. Spatial and temporal variations of trace metals are discussed with special reference to pH, dissolved oxygen, salinity, organic carbon and texture of sediment. Metal concentrations in the tide gated part of the estuary were found to be significantly higher when compared to metal concentrations reported from the unrestricted part of the Cochin estuarine system and also those from many of the unpolluted estuaries worldwide. The higher levels of heavy metals in the study area and their characteristic distribution and partitioning behaviour in the surficial sediments were attributed to the presence of a salinity barrier across the backwater system and also by the massive use of pesticides and chemical fertilizers in the vast area of agricultural land near the backwater system.  相似文献   
5.
The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.  相似文献   
6.
7.

INTRODUCTION:

Non-syndromic tooth agenesis is a congenital anomaly with significant medical, psychological, and social ramifications. There is sufficient evidence to hypothesize that locus for this condition can be identified by candidate genes.

AIM OF THE STUDY:

The aim of this study was to test whether MSX1 671 T > C gene variant was involved in etiology of non-syndromic tooth agenesis in Raichur patients.

MATERIALS AND METHODS:

Blood samples were collected with informed consent from 50 subjects having non-syndromic tooth agenesis and 50 controls. Genomic deoxyribonucleic acid (DNA) was extracted from the blood samples, polymerase chain reaction (PCR) was performed, and restriction fragment length polymorphism (RFLP) was performed for digestion products that were evaluated.

RESULTS:

The results showed positive correlation between MSX1671 T > C gene variant and non-syndromic tooth agenesis in Raichur patients.

CONCLUSION:

MSX1 671 T > C gene variant may be a good screening marker for non-syndromic tooth agenesis in Raichur patients.  相似文献   
8.

BACKGROUND:

Mental retardation (MR) is a heterogeneous dysfunction of the central nervous system exhibiting complex phenotypes and has an estimated prevalence of 1-3% in the general population. However, in about 50% of the children diagnosed with any form of intellectual disability or developmental delay the cause goes undetected contributing to idiopathic intellectual disability.

MATERIALS AND METHODS:

A total of 122 children with developmental delay/MR were studied to identify the microscopic and submicroscopic chromosome rearrangements by using the conventional cytogenetics and multiplex ligation dependent probe amplification (MLPA) analysis using SALSA MLPA kits from Microbiology Research Centre Holland [MRC] Holland.

RESULTS:

All the recruited children were selected for this study, after thorough clinical assessment and metaphases prepared were analyzed by using automated karyotyping system. None was found to have chromosomal abnormality; MLPA analysis was carried out in all subjects and identified in 11 (9%) patients.

CONCLUSION:

Karyotype analysis in combination with MLPA assays for submicroscopic micro-deletions may be recommended for children with idiopathic MR.  相似文献   
9.
10.
Chemerin, a chemoattractant ligand for chemokine-like receptor 1 (CMKLR1) is predicted to share similar tertiary structure with antibacterial cathelicidins. Recombinant chemerin has antimicrobial activity. Here we show that endogenous chemerin is abundant in human epidermis, and that inhibition of bacteria growth by exudates from organ cultures of primary human skin keratinocytes is largely chemerin-dependent. Using a panel of overlapping chemerin-derived synthetic peptides, we demonstrate that the antibacterial activity of chemerin is primarily mediated by Val66-Pro85, which causes direct bacterial lysis. Therefore, chemerin is an antimicrobial agent in human skin.  相似文献   
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