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71.
72.

Background  

Phylogenetic analysis of human complete mitochondrial DNA sequences has largely contributed to resolving phylogenies and antiquity of different lineages belonging to the majorhaplogroups L, N and M (East-Asian lineages). In the absence of whole mtDNA sequence information of M lineages reported in India that exhibits highest diversity within the sub-continent, the present study was undertaken to provide a detailed analysis of this haplogroup to precisely characterize the lineages and unravel their intricate phylogeny.  相似文献   
73.
Monoclonal antibodies (MoAbs) were generated following immunization of Balb/C mice with adenovirus type 5 grown in Hep2 cell line. Six clones reactive to hexon antigen of the virus were stabilized, of which 4 had mu-heavy chain specificity and 2 were of gamma-heavy chain type. Three of the clones (ADV-1, ADV-3 and ADV-5) had a high ELISA reactivity to the hexon antigen but exhibited differential specificity to the adenovirus types tested. In Western blotting, ADV-1 and ADV-3 reacted with all the adenovirus types tested (types 3,4,5,7 and 8) with reactions at 116 kDa region (hexon antigen), in addition, ADV-3 also had reactivity at 80 kDa region, the penton antigen. Reactivity to these adenoviral types by the 2 MoAbs was demonstrable by dot ELISA. ADV-5 had a type specific reaction only to adenovirus type 5 in dot ELISA with specificity in the hexon region in Western blotting. The reactivity of these 3 clones was not observed to the normal Hep2 tissue culture antigens and to the 3 enteroviruses tested (polio, coxsackie A9 and echo 4).  相似文献   
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Hatha , Lekh R. (U. Kansas, Lawrence.) Contributions to our knowledge of ambrosia fungi. II. Endomycopsis fasciculat nom. nov. (Ascomycetes). Amer. Jour. Bot. 50(5): 481–487. Illus. 1963.—Endomyceu bispora Verrall (1943) is a later homonym of E. bisporus Beck (1922) (= Endomycopsis bispora [Beck] Dekker), and the former is now described under the new name Endomycopsis fasciculata Batra. The ambrosia beetle Gnathotrichus materiarius (Fitch) lives symbiotically with Endomycopsis fasciculata which serves as the major source of food for the larvae and probably for the adults. The fungus forms an extensive palisade lining throughout the larval or pupal cells and the main tunnel dug by the mother. All stages of the fungus can be obtained from the same tunnel and the fungus seems to be homothallic. The asci are typically 2-spored and aseosporcs are eucullate. The fungus does not assimilate nitrate as the sole source of nitrogen. Detailed morphology and nutritional requirements of E. fasciculata are discussed.  相似文献   
77.
Acute normovolemic hemodilution (ANH) is efficient in reducing allogenic blood transfusion needs during elective surgery. Tissue oxygenation is maintained by increased cardiac output and oxygen extraction and, presumably, a more homogeneous tissue perfusion. The aim of this study was to investigate blood flow distribution and oxygenation of skeletal muscle. ANH from hematocrit of 36 +/- 3 to 20 +/- 1% was performed in 22 splenectomized, anesthetized beagles (17 analyzed) ventilated with room air. Normovolemia was confirmed by measurement of blood volume. Distribution of perfusion within skeletal muscle was determined by using radioactive microspheres. Tissue oxygen partial pressure was assessed with a polarographic platinum surface electrode. Cardiac index (3.69 +/- 0.79 vs. 4.79 +/- 0.73 l. min-1. m-2) and muscle perfusion (4.07 +/- 0.44 vs. 5.18 +/- 0.36 ml. 100 g-1. min-1) were increased at hematocrit of 20%. Oxygen delivery to skeletal muscle was reduced to 74% of baseline values (0.64 +/- 0.06 vs. 0.48 +/- 0.03 ml O2. 100 g-1. min-1). Nevertheless, tissue PO2 was preserved (27.4 +/- 1.3 vs. 29.9 +/- 1. 4 Torr). Heterogeneity of muscle perfusion (relative dispersion) was reduced after ANH (20.0 +/- 2.2 vs. 13.9 +/- 1.5%). We conclude that a more homogeneous distribution of perfusion is one mechanism for the preservation of tissue oxygenation after moderate ANH, despite reduced oxygen delivery.  相似文献   
78.
OBJECTIVE: To evaluate the value of percentage cell counts and cell indices in testicular fine needle aspiration cytology (FNAC) in male infertility and their correlation with histologic categories as seen in open testicular biopsies. STUDY DESIGN: Differential cell counts were performed, and cell indices, including spermatic index, Sertoli cell index and sperm-Sertoli cell index, were calculated in testicular fine needle aspiration (FNA) smears in 30 azoospermic males whose open testicular biopsies were classified as normal spermatogenesis in 10 cases, maturation arrest in 5, hypospermatogenesis in 6, Sertoli cell only syndrome in 5 and tubular/peritubular sclerosis in 4. RESULTS: In normal spermatogenesis, FNA smears showed up to 40% Sertoli cells, and spermatozoa were the predominant spermatogenetic cell type. There was a progressive increase in Sertoli cell percentage and Sertoli cell index and reduction in spermatozon percentage, spermatic index and sperm-Sertoli cell index with increasing severity of reduction in spermatogenesis in different histologic categories. The differences between mean counts and indices in normal spermatogenesis and other histologic categories were statistically significant (P < .01). CONCLUSION: The percent cell counts and cell indices in testicular FNAC correlate with histologic categories and are useful in evaluating male infertility.  相似文献   
79.
Climate change, humans, and the extinction of the woolly mammoth   总被引:1,自引:0,他引:1  
Woolly mammoths inhabited Eurasia and North America from late Middle Pleistocene (300 ky BP [300,000 years before present]), surviving through different climatic cycles until they vanished in the Holocene (3.6 ky BP). The debate about why the Late Quaternary extinctions occurred has centred upon environmental and human-induced effects, or a combination of both. However, testing these two hypotheses—climatic and anthropogenic—has been hampered by the difficulty of generating quantitative estimates of the relationship between the contraction of the mammoth's geographical range and each of the two hypotheses. We combined climate envelope models and a population model with explicit treatment of woolly mammoth–human interactions to measure the extent to which a combination of climate changes and increased human pressures might have led to the extinction of the species in Eurasia. Climate conditions for woolly mammoths were measured across different time periods: 126 ky BP, 42 ky BP, 30 ky BP, 21 ky BP, and 6 ky BP. We show that suitable climate conditions for the mammoth reduced drastically between the Late Pleistocene and the Holocene, and 90% of its geographical range disappeared between 42 ky BP and 6 ky BP, with the remaining suitable areas in the mid-Holocene being mainly restricted to Arctic Siberia, which is where the latest records of woolly mammoths in continental Asia have been found. Results of the population models also show that the collapse of the climatic niche of the mammoth caused a significant drop in their population size, making woolly mammoths more vulnerable to the increasing hunting pressure from human populations. The coincidence of the disappearance of climatically suitable areas for woolly mammoths and the increase in anthropogenic impacts in the Holocene, the coup de grâce, likely set the place and time for the extinction of the woolly mammoth.  相似文献   
80.
Synthesis of new 6-ureido-4-anilinoquinazolines have been accomplished and their in vitro antimalarial activity against chloroquine-sensitive P. falciparum have been examined. Out of 64 compounds evaluated, the IC50 of 16 compounds which have displayed MIC of 0.25 μg/mL were also recorded. One of the compounds (24g) had IC50 value of 2.27 ng/mL which was equipotent to the standard drug chloroquine used in the bioassay. The in vivo evaluation of a few compounds among the series led to discovery of one analog (30g) displaying 40% curative activity (28 days) against mdr P. yoeilli nigeriensis at an oral dose of 100 mg/kg × 4days.  相似文献   
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