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1.
A. Bagga 《International Journal of Anthropology》1987,2(2):157-165
The terminations of the Main Line—C on the plams of 390 schizophrenic male patients were analysed and classified into four
modal types according to the direction of their path following Plato's classification (1970). Schizophrenic patients classified
into three major sub-categories namely Paranoid (256 palms) Hebephrenic (256 palms), Catatonic (202 palms) and Undifferentiated
(66 palms), were taken from the same ethnic group from Yerawada Mental Hospital, Pune and Sassoon General Hospital, Pune (India).
Comparisons were made with the respective normal caste control. The frequency of these four model types exhibit strong variations
among themselves and between the patients belonging to the sub-categories of schizophrenia. Considerable increase has been
observed on the Left Palm of the Paranoid and Catatonic patients for the incidence of Radial and Proximal types. The incidence
of Ulnar type showed consistent decrease bilaterally, among all the sub-categories. Absent types showed a steep increase in
all the sub-categories of Schizophrenic. 相似文献
2.
Complementary to our previous project on the molecular phylogeny of Camphorosmeae, the leaf anatomy of ca. 35 species including all non-Australian and selected Australian species was studied by use of light microscopy. Nine anatomical leaf types were described, compared to previous classifications, and discussed with regard to their putative evolution on the background of phylogenetic trees. Particular emphasis was given to the relationships between the C3 and C4 leaf types: Chenolea type (C3), Eokochia type (C3), Neokochia type (C3), Sedobassia type (C3/C4 intermediate), Bassia prostrata type (C4), B. muricata type (C4), B. eriantha type, B. lasiantha type (C4), Camphorosma type (C4). The main results and conclusions were: (1) Two unusual new C3 leaf types: Chenolea with microfenestrate chlorenchyma, Eokochia with unique complex vascular bundles; (2) Sedobassia interpreted as anatomically C3/C4 intermediate by kranz-like bundle sheath cells is the first C3/C4 intermediate in Camphorosmeae and found in a derived position; (3) Neokochia type detected as the likely starting point for all four C4 leaf types and for the C3/C4 intermediate; (4) hypodermis of C4 types originated from outermost chlorenchyma layer of C3 types and lost multiple times during further evolution; (5) atriplicoid Bassia. lasiantha type without water storage tissue evolved from kochioid B. muricata type; (6) two independent gains of C4 photosynthesis, one in Bassia and one in Camphorosma; (7) depending on the lineage, leaf architecture remains comparatively stable (Australian Camphorosmeae) or shows an unexpected plasticity (Bassia scoparia group). 相似文献
3.
The time course of the endplate current is determined by the rate and equilibrium constants for acetylcholine receptor (AChR) activation. We measured these constants in single-channel currents from AChRs with mutations at the neurotransmitter-binding sites, in loop C. The main findings are: (a) Almost all perturbations of loop C generate heterogeneity in the channel open probability (“modes”). (b) Modes are generated by different affinities for ACh that can be either higher or lower than in the wild-type receptors. (c) The modes are stable, in so far as each receptor maintains its affinity for at least several minutes. (d) Different agonists show different degrees of modal activity. With the loop C mutation αP197A, there are four modes with ACh but only two with partial agonists. (e) The affinity variations arise exclusively from the αδ-binding site. (f) Substituting four γ-subunit residues into the δ subunit (three in loop E and one in the β5–β5′ linker) reduces modal activity. (g) At each neurotransmitter-binding site, affinity is determined by a core of five aromatic residues. Modes are eliminated by an alanine mutation at δW57 but not at the other aromatics. (h) Modes are eliminated by a phenylalanine substitution at all core aromatics except αY93. The results suggest that, at the αδ agonist site, loop C and the complementary subunit surface can each adopt alternative conformations and interact with each other to influence the position of δW57 with respect to the aromatic core and, hence, affinity. 相似文献
4.
颞线作为头骨表面咀嚼肌颞肌的附着痕迹,其形态变异对探讨人类体质特征及咀嚼功能具有一定意义。为了解颞线在现代人群中的变异情况,本文选取亚洲、非洲和欧洲278例近现代成年人头骨为研究材料,通过对颞线的颞弧形态、宽度、发育程度、粗糙度及末端位置的观察和分析,明确颞线的分类及其定义标准,获取颞线各种表现形式的侧别、性别和地区间变异的数据,为体质人类学的研究提供参考资料。研究结果显示:1)颞线无显著侧别间差异;2)颞弧形态和发育程度无显著性别和地区间差异;3)顶部颞线宽度及粗糙度有显著性别间差异:男性顶部颞线整体较宽,粗糙型个体大多为男性;4)额部和顶部颞线宽度及粗糙度有显著地区间差异:超宽条带状颞线只出现在云南和华北地区标本,欧洲地区标本脊状颞线和粗糙型比例较高,非洲地区脊状颞线比例较高但粗糙型较低;5)颞线末端止于枕骨的类型极少;6)颞线宽度在额部和顶部及其与颞弧形态显著相关,颞线发育程度在额部与顶部显著相关。 相似文献
5.
Pyankov VI Voznesenskaya EV Kuz'min AN Ku MS Ganko E Franceschi VR Black CC Edwards GE 《Photosynthesis research》2000,63(1):69-84
Most species of the genus Salsola (Chenopodiaceae) that have been examined exhibit C4 photosynthesis in leaves. Four Salsola species from Central Asia were investigated in this study to determine the structural and functional relationships in photosynthesis of cotyledons compared to leaves, using anatomical (Kranz versus non-Kranz anatomy, chloroplast ultrastructure) and biochemical (activities of photosynthetic enzymes of the C3 and C4 pathways, 14C labeling of primary photosynthesis products and 13C/12C carbon isotope fractionation) criteria. The species included S. paulsenii from section Salsola, S. richteri from section Coccosalsola, S. laricina from section Caroxylon, and S. gemmascens from section Malpigipila. The results show that all four species have a C4 type of photosynthesis in leaves with a Salsoloid type Kranz anatomy, whereas both C3 and C4 types of photosynthesis were found in cotyledons. S. paulsenii and S. richteri have NADP- (NADP-ME) C4 type biochemistry with Salsoloid Kranz anatomy in both leaves and cotyledons. In S. laricina, both cotyledons and leaves have NAD-malic enzyme (NAD-ME) C4 type photosynthesis; however, while the leaves have Salsoloid type Kranz anatomy, cotyledons have Atriplicoid type Kranz anatomy. In S. gemmascens, cotyledons exhibit C3 type photosynthesis, while leaves perform NAD-ME type photosynthesis. Since the four species studied belong to different Salsola sections, this suggests that differences in photosynthetic types of leaves and cotyledons may be used as a basis or studies of the origin and evolution of C4 photosynthesis in the family Chenopodiaceae.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
6.
C. Hoff C. C. Plato R. M. Garruto J. Dutt 《American journal of physical anthropology》1981,55(4):455-461
Genetic distance techniques and cluster analysis were used to determine which dermatoglyphic parameters were most useful in assessing genetic relationships between native American populations. The dermatoglyphic parameters used for this analysis were those most completely reported in the papers examined in a literature survey we had carried out previously, and include digital patterns, modal types of the C-line and D-line terminations, and palmar patterns in the hypothenar, thenar/I, and interdigital areas. The populations examined were separated by sex and divided into seven major geographical groups: Eskimo; North American Indian; Maya and non-Maya (Central America); Amazonian; Quechua, and Aymara (South America). Mean frequencies of dermatoglyphic traits were computed for each group and pairwise “genetic” distances calculated using Cavalli-Sforza and Edward's D-test. Dendrograms were then generated from these D-values using Q-mode cluster analysis. Using the hypothenar, thenar/I and III and IV interdigital areas, the results of this analysis demonstrated a good fit to an expected phylogenetic tree. When digital patterns, patterns in the II interdigital area, and the modal types of the C-line were included in the analysis, the same phylogenetic relationships were observed. However, inclusion of the modal types of the D-line with the other parameters tended to introduce some distortion and a greater separation between sexes within the same populations. 相似文献
7.
Abstract Two endocrine cell types, PbH+ and PAS+ cells, were recognized in the pars intermedia (PI) of the roach, Leuciscus rutilus, by light and electron microscopy. They can be distinguished by the appearance of their secretory granules. The PAS+ cells stain with toluidine blue in semithin sections as opposed to the PbH+ cells. After 5 days' treatment with metopirone the PbH+ cells are highly activated whereas the PAS+ cells show no response. The PbH+ cells are assumed to produce MSH. In roaches adapted to diluted sea water (10%) the transfer to fresh water for 1—1 1/2 hours or reserpine injections for the same period had no notable effect on neither cell type. Three kinds of axons innervate the PI. Two of these, which have granules averaging 111 nm and 151 nm in diameter, originate in the nucleus preopticus (NPO). The third type of axons has granules of an average size of 74 nm and is probably aminergic. The glia cells in this part of the neurohypophysis (NH) are granular pituicytes, which are innervated by all three axon types. The border between the NH and the PI is composed of a double basement membrane from which a network extends into the NH. This network, the basement membrane and the capillaries are the main sites for the terminations of the axons although nerve fibers also invade the endocrine tissue. Only axon type 3 was observed to synapse frequently with the PbH+ cells. 相似文献
8.
The pollen grains of 32 species, 1 subspecies and 4 varieties of Vitis and 1 species of
Muscadinia were scanned with Hitachi S-800 scanning electron microscope and described in the present paper. In Vitis, the pollen morphology is found to be valuable for the identification of species,
though it is of little significance in supraspecific classification and systematic consideration. The ornamentation of Vitis could be divided into four types: ( 1 ) The pollen grains are oblate or rarely
spheroidal (P/E =0.97 ~ 1.08) in shape, with colpi wide enough to show dense granulae inside.
The pollen grains of V. coignetiae Pull. Ex Planch. belong to this type. (2) The pollen grains are
prolate to subprolate (P/E = 1.25 ~ 1.76 ), with sparse granulae within the colpi. This type includes l0 species, 1 subspecies and 3 varieties, such as V. hui Cheng etc. (3) The pollen grains
of V. romanetii Roman du Caill. ex Planch. and V. davidii (Roman du Caill. ) Foex. var. ferruginea Merr. et Chun are prolate (P/E= 1.87 ~ 2.1), with colpi narrow and linear-shaped, but
rhombic in the equational region. (4) The pollen grains are prolate or perprolate (P/E= 1.30 ~ 2.
0), with narrow and linear-shaped colpi. The species with this type of pollen grains are Muscadiniarotundifolia (Michx.) Small and 20 species of Vitis. 相似文献
9.
Kye Chung Park Mark McNeill C. Rikard Unelius Hyun-Woo Oh David M. Suckling 《Journal of insect physiology》2013,59(12):1222-1234
Antennal olfactory receptor neurons (ORNs) for pheromone and plant volatile compounds were identified and characterized in male and female clover root weevil, Sitona lepidus (Gyllenhal), using the single sensillum recording technique with five pheromone-related compounds, and 40 host and non-host plant volatile compounds. Overall, seven different types of olfactory sensilla containing specialized ORNs were identified in each sex of S. lepidus. Among them, three different types of sensilla in the males and two types in the females housed ORNs specialized for pheromone-related compounds. The ORNs in males were specialized for 4-methyl-3,5-heptanedione or one or more of four stereoisomers of 5-hydroxy-4-methyl-3-heptanone. In contrast, female sensilla did not contain ORNs sensitive to 4-methyl-3,5-heptanedione while they contained ORNs sensitive to and specialized for the stereoisomers of (4S,5S)-5-hydroxy-4-methyl-3-heptanone. In addition to the pheromone-related ORNs, four types of olfactory sensilla contained ORNs responsive to plant volatile compounds in male S. lepidus, and five types in females. Most of the ORNs identified in S. lepidus showed a high degree of specificity to specific volatile compounds although some of the active compounds showed overlapping response spectra in the ORNs across different types of sensilla. The most active plant volatile compounds were the four green leaf volatile compounds, (E)-2-hexenol, (Z)-2-hexenol, (Z)-3-hexenol and (E)-2-hexenal, and isomers of two monoterpenols, (±)-linalool and (±)-α-terpineol, all eliciting strong responses from relatively large numbers of ORNs in male and female S. lepidus. Our study indicates that S. lepidus has a set of highly sensitive and selective ORNs for pheromone and plant volatile compounds. Further work is needed to elucidate the behavioral implications of these findings. 相似文献
10.
Classic stem cell theory states that the growth of heteroploid cell populations is due to the proliferation of 'main stemline'cells with modal DNA content and chromosome number. Cells with non-modal DNA content and chromosome number are thought to be blocked and/or destroyed at mitosis. To test this, we studied two chromo-somally stable cell populations (mouse bone marrow and WCHE-5 cells) and one heteroploid, chromosomally diverse cell line (MCa-11). The heteroploid MCa-11 cells showed significant [3 H]dT labelling for cells with DNA contents below the modal Go /G1 peak and above the modal G2 peaks ( P <0.001). This was consistent with the presence of cells with the non-modal DNA content that were engaged in replicative DNA synthesis. A percentage labelled mitosis analysis showed that MCa-11 cells with non-modal DNA content and chromosome number were able to complete mitosis, although with prolonged pre-karyokinetic time. These results suggest that many non-modal cells present in heteroploid cell populations are capable of continued proliferation. 相似文献
11.
Yasumitsu Nakai 《Cell and tissue research》1971,119(2):164-178
Summary In the frog median eminence, fixed with glutaraldehyde and osmium tetroxide, four types of nerve endings can be generally distinguished. These endings are in contact with the pericapillary spaces of primary portal vessels and can be identified by the internal structure and the size of their granules and vesicles. Type 1 contains large granules (1500–2400 Å in diameter) and small clear vesicles (300–500 Å in diameter), type 2 intermediate granules (about 1100–1700 Å in diameter) and small clear vesicles, type 3 small granules (about 600–1000 Å in diameter) and small clear vesicles, type 4 only numerous small clear vesicles. The mixed types containing the large, intermediate and small dense granules in the same ending are infrequently found.After KMnO4 or LiMnO4 fixation the granules and vesicles mentioned above are observed as follows. The large granules in the type 1 nerve ending appear mostly pale or less-dense. The intermediate granules in the type 2 also appear mostly pale or less-dense, but some frequently show granules of high density. The small granules in the type 3 consistently contain the dense substance and these endings can be subdivided into two different types according to the populations of different sizes of dense granules [type 3a (900–1000 Å) and type 3b (500–800 Å)]. Dense-cored and cleared-synaptic vesicles are frequently present with together in the type 3 endings. The small vesicles (300–400 Å), in the type 4, appear generally pale (type 4a), but some nerve endings contain small dense cored-vesicles (type 4b).The author wishes to thank Prof. H. Fujita for his advice and criticism. 相似文献
12.
Streptococcus pneumoniae group 9 includes four capsular polysaccharide types: 9A, 9L, 9N and 9V. We have generated four mouse monoclonal antibodies against group 9 polysaccharide using heat-treated S. pneumoniae strains of different capsular polysaccharides types as immunogens. The specificities of the monoclonal antibodies were determined by ELISA using capsular polysaccharide directly coated to the wells as antigens and by dot blotting with heat-treated bacteria. Two groups of monoclonal antibodies were found. The first group included two monoclonal antibodies which were found to be capsular type specific. The second group was monoclonal antibodies that bound to epitopes shared by two or three pneumococcal group 9 types. The monoclonal antibody 204,A-4 (IgM) was found to be specific for S. pneumoniae type 9N. The binding of the type 9V specific monoclonal antibody 206,F-5 (IgG1) was found to be dependent upon O-acetyl groups. Monoclonal antibody 205,F-3 (IgM) reacted also with type 9V, but was found to cross-react with types 9A and 9L. The binding of this monoclonal antibody to polysaccharide 9V was not dependent upon O-acetyl moieties. The fourth monoclonal antibody (214,G-5, isotype IgM) did not show any correlation between reactivity with isolated polysaccharides and dot blotting with relevant bacteria. The monoclonal antibody reacted with polysaccharides 9A and 9L in ELISA, but not with the homologous bacteria. 相似文献
13.
Amel Guezguez Fréderic Paré Yannick D. Benoit Nuria Basora Jean-François Beaulieu 《Experimental cell research》2014
The small intestine consists of two histological compartments composed of the crypts and the villi. The function of the adult small intestinal epithelium is mediated by four different types of mature cells: enterocytes, goblet, enteroendocrine and Paneth. Undifferentiated cells reside in the crypts and produce these four types of mature cells. The niche-related Wnt and Bmp signaling pathways have been suggested to be involved in the regulation and maintenance of the stem cell microenvironment. In our laboratory, we isolated the first normal human intestinal epithelial crypt (HIEC) cell model from the human fetal intestine and in this study we investigated the expression of a panel of intestinal stem cell markers in HIEC cells under normal culture parameters as well as under conditions that mimic the stem cell microenvironment. The results showed that short term stimulation of HIEC cells with R-spondin 1 and Wnt-3a±SB-216763, a glycogen synthase kinase 3β (GSK3β) inhibitor, induced β-catenin/TCF activity and expression of the WNT target genes, cyclin D2 and LGR5. Treatment of HIEC cells with noggin, an antagonist of BMP signaling, abolished SMAD2/5/8 phosphorylation. Inducing a switch from inactive WNT/active BMP toward active WNT/inactive BMP pathways was sufficient to trigger a robust intestinal primordial stem-like cell signature with predominant LGR5, PHLDA1, PROM1, SMOC2 and OLFM4 expression. These findings demonstrate that even fully established cultures of intestinal cells can be prompted toward a CBC stem cell-like phenotype. This model should be useful for studying the regulation of human intestinal stem cell self-renewal and differentiation. 相似文献
14.
Cytogenetic studies were performed on two types of Japanese hagfish (Eptatretus okinoseanus) that eliminate about 45% (type A) and 55% (type B) of their DNA from presumptive somatic cells during the differentiation of somatic cells. The observations revealed inter- and intraindividual variations in the number of chromosomes in germ cells of both types of hagfishes. Although the modal number of chromosomes in the germ cells was 54 in both types, the percentage of cells with the modal number was rather low (38.6% [51/132] in five specimens of type A and 22.7% [25/110] in eight specimens of type B). In addition, one of seven type B specimens clearly had a modal number of 62 chromosomes. Another specimen of type B had a bimodal distribution of chromosome numbers, with peaks of 54 and 59 chromosomes. The observation of interindividual variations was supported by data on the amount of DNA in germ cells of type B specimens. However, these variations were rarely observed in somatic cells. These results suggest that supernumerary (B) chromosomes are maintained in germ cells and are eliminated together with some other chromosomes and/or chromatin from somatic cells. 相似文献
15.
Enhanced reactive lysis of paroxysmal nocturnal hemoglobinuria erythrocytes by C5b-9 does not involve increased C7 binding or cell-bound C3b 总被引:8,自引:0,他引:8
S I Rosenfeld D E Jenkins J P Leddy 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(1):506-511
The most complement (C)-sensitive type of erythrocytes (E) occurring in paroxysmal nocturnal hemoglobinuria (type III PNH E) have previously been found to exhibit approximately twofold to fourfold greater lysis than normal human E when exposed to isolated human C5b6, C7, C8, and C9 (reactive lysis), in the absence of a known source of C3- or C5-convertases or fluid-phase C3. In further studies on the mechanism of this phenomenon, we now report that C5b6-dependent binding of 125I-C7 to two samples of PNH E (greater than 95% type III) is equal to that found with normal human E at each of several C5b6 inputs tested. Lysis developed by excess C8 and C9, however, was consistently greater for the PNH E. Thus, the exaggerated sensitivity of type III PNH E to reactive lysis cannot be explained by abnormally high uptake of C5b6 or C7 from the fluid phase. Rather, the data indicate that cell-bound C5b67 sites are converted to effective hemolytic sites with greater efficiency on type III PNH E than on normal human E, assuming that the distribution of cell-bound C7 throughout both cell populations is similar. In related studies we have addressed the proposal by other investigators that C3b putatively bound to PNH E in vivo might account for their increased sensitivity to reactive lysis in vitro, by analogy to prior observations on C3b-potentiated reactive lysis of sheep E. The latter hypothesis was made more appealing by the recent discovery that type III PNH E lack an integral membrane protein, decay-accelerating factor (DAF), which in normal E accelerates the decay of membrane-bound C3 convertases. Against this hypothesis, however, is our present finding that preincubation of PNH E with four different goat or rabbit polyclonal antibodies to human C3 failed to inhibit the subsequent reactive lysis of these cells. Under these same conditions, the C3b-dependent increment in reactive lysis of sheep EAC4b3b was abrogated by pretreatment with similar dilutions of these anti-C3 antibodies, generally in association with agglutination. Furthermore, sheep EAC4b3b displayed increased 125I-C7 binding in proportion to augmented lysis, in contrast to the findings with PNH E. Therefore, deficiency of DAF in type III PNH E does not adequately explain their supranormal sensitivity to reactive lysis unless DAF can modulate the terminal lytic steps by a mechanism distinct from its effect on C3 convertase decay. Alternatively, type III PNH E could have a more general abnormality in which DAF deficiency is one manifestation and increased sensitivity to reactive lysis is another. 相似文献
16.
Characteristics of the plasma membrane of Sporothrix scheckii cells as revealed by freeze-fracture techniques have been classified into eight types (Y1, Y2a, Y2b, Y3a, Y3b, Y4a, Y4b, and Y5) in yeastlike cells grown under the following two conditions: brain heart infusion agar medium at 27 degrees C, and brain heart infusion agar medium at 37 degrees C. Type Y1 cells are yeastlike cells having smooth plasma membranes without any invagination. Typical characteristics of the other types are as follows: type Y2a, smooth plasma membranes with few trenchlike invaginations; type Y2b, wavy plasma membranes with few oval or irregularly formed invaginations; type Y3a, plasma membranes with many randomly distributed trenchlike invaginations; type Y3b, plasma membranes with many cocoonlike or irregularly formed invaginations; type Y4a, plasma membranes with longer trenchlike invaginations; type Y4b, plasma membranes with irregularly formed, enlarged invaginations; and type Y5, smooth or wavy plasma membranes with aggregations of intramembranous particles and with many vacuoles between cell walls and plasma membranes or in the cytoplasm in some cells. By counting the proportion of each type of yeastlike cell under the two conditions and with different cultivation periods, it appears that plasma membrane types change as aging progresses in the following order: type Y1, Y2a, Y3a, Y4a, and Y5 in conidia and type Y1, Y2b, Y3b, Y4b, and Y5 in yeastlike vegetative cells. These observations provide us with an important advantage when studying the effects of antifungal agents on the plasma membrane of Sporothrix scheckii, as it is important to know the natural course of changes in membrane structure during aging. 相似文献
17.
Activation of complement component C5: comparison of C5 convertases of the lectin pathway and the classical pathway of complement 总被引:1,自引:0,他引:1
Although the initiating complex of lectin pathway (called M1 in this study) generates C3/C5 convertases similar to those assembled by the initiating complex (C1) of the classical pathway, activation of complement component C5 via the lectin pathway has not been examined. In the present study kinetic analysis of lectin pathway C3/C5 convertases assembled on two surfaces (zymosan and sheep erythrocytes coated with mannan (E(Man))) revealed that the convertases (ZymM1,C4b,C2a and E(Man)M1,C4b,C2a) exhibited a similar but weak affinity for the substrate, C5 indicated by a high K(m) (2.73-6.88 microm). Very high affinity C5 convertases were generated when the low affinity C3/C5 convertases were allowed to deposit C3b by cleaving native C3. These C3b-containing convertases exhibited K(m) (0.0086-0.0075 microm) well below the normal concentration of C5 in blood (0.37 microm). Although kinetic parameters, K(m) and k(cat), of the lectin pathway C3/C5 convertases were similar to those reported for classical pathway C3/C5 convertases, studies on the ability of C4b to bind C2 indicated that every C4b deposited on zymosan or E(Man) was capable of forming a convertase. These findings differ from those reported for the classical pathway C3/C5 convertase, where only one of four C4b molecules deposited formed a convertase. The potential for four times more amplification via the lectin pathway than the classical pathway in the generation of C3/C5 convertases and production of pro-inflammatory products, such as C3a, C4a, and C5a, implies that activation of complement via the lectin pathway might be a more prominent contributor to the pathology of inflammatory reactions. 相似文献
18.
Sprague-Dawley rats were given 0.02 ml of methylprednisolone (0.06 g/g body wt) 6, 9, or 12 days postnatally. When compared with saline-treated controls, the following effects on dendritic development in layers 3 and 5 of the parietal cortex were observed: (1) no significant alteration in number of basal dendrites; (2) initial increase (at 3 wk of age) in branchings near the perikaryon in the group treated at 12 days; (3) decrease in number of branches at distances ≥270 μm from the perikaryon in layers 3 and 5 in all steroid-treated groups when sacrificed at 6 wk; (4) decrease in number of intersections in layer 5 in all steroid-treated groups when sacrificed at 6 wk; and (5) decrease in number of terminations in layers 3 and 5 in all steroid-treated groups when sacrificed at 6 wk. 相似文献
19.
M Nawa 《Microbiology and immunology》1984,28(7):765-776
A newly established cell line, GK, derived from the kidney tissue of Mongolian gerbils, produced plaques by infection of prototype and wild-type dengue virus strains. Both prototype and wild strains of type 2 virus grew in GK cells and formed plaques at 35.5 C and at 31 C, while types 1, 3, and 4 wild strains grew and formed plaques only at 31 C. In GK cells, plaque formation and the growth of dengue viruses depended on the high (35.5 C) and low (31 C) incubation temperatures. Virus yields in GK cells of all the 14 dengue virus strains tested, including four prototype and ten wild-type viruses, were 5 to 1,000-times lower than those in C6/36 cells. After five serial passages in GK cells, types 2, 3, and 4 prototype viruses and type 2 wild strain increased virus yields, and one strain of prototype virus and one strain of wild-type virus decreased mouse neurovirulence. 相似文献
20.
Abstract. 1. Invertebrate data identified to coarse groupings according to taxonomy or ecology are easier to obtain than species-level data. However, it is unclear if such data are suitable for detecting environmental change.
2. We compared the performance of four types of data (species, family, trophic group, and body size) to quantify the responses of beetle assemblages with three types of environmental change on the Atherton Tableland in north-eastern Queensland, Australia. Clearing of rainforest creates two levels of environmental change: first the extreme, forest loss, and second, the more subtle change associated with forest fragmentation. A strong rainfall gradient across the study landscape also influences the biota, imposing a third type of environmental change, independent of rainforest modification.
3. Almost 20 000 beetles were sampled from six replicate sites in each of pasture, small rainforest remnants, and both the edges and interiors of large rainforest remnants.
4. All four types of data showed significant multivariate differences in assemblage composition between pasture and rainforest sites. Species-level data in multivariate analyses showed an effect of fragmentation on small remnants and also showed variation which corresponded with the spatial aridity gradient across sites. Both of these patterns were only weakly evident or were non-existent at the level of family, trophic group, or body size class. No level of taxonomic resolution gave consistently stronger results when univariate tests were applied to individual component taxa.
5. We conclude that data above the species level may not have the sensitivity required to detect more subtle forms of environmental change. 相似文献
2. We compared the performance of four types of data (species, family, trophic group, and body size) to quantify the responses of beetle assemblages with three types of environmental change on the Atherton Tableland in north-eastern Queensland, Australia. Clearing of rainforest creates two levels of environmental change: first the extreme, forest loss, and second, the more subtle change associated with forest fragmentation. A strong rainfall gradient across the study landscape also influences the biota, imposing a third type of environmental change, independent of rainforest modification.
3. Almost 20 000 beetles were sampled from six replicate sites in each of pasture, small rainforest remnants, and both the edges and interiors of large rainforest remnants.
4. All four types of data showed significant multivariate differences in assemblage composition between pasture and rainforest sites. Species-level data in multivariate analyses showed an effect of fragmentation on small remnants and also showed variation which corresponded with the spatial aridity gradient across sites. Both of these patterns were only weakly evident or were non-existent at the level of family, trophic group, or body size class. No level of taxonomic resolution gave consistently stronger results when univariate tests were applied to individual component taxa.
5. We conclude that data above the species level may not have the sensitivity required to detect more subtle forms of environmental change. 相似文献