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181.
The aim of this study was to investigate the possible effects of the seasonal and physiological variations on the Cu, Zn,
Mg, Fe, Se, Ca, K, Na, Cl, and P concentrations and their relationships with the estradiol and progesterone levels in Sakiz-Ivesi
sheep. For this purpose 34 healthy Sakiz-Ivesi crossbreed sheep were divided into two groups. The first group (n=22) was mated and the second group (n=12) was not mated. They were raised under pasture conditions and without any dietary supplementation. Their serum samples
were collected four times a year at each season and under each physiologic condition. The periods are 1=early pregnancy (October),
2=late pregnancy (January), 3=lactation (April), and 4=dry season (July).
The results of this study indicated that (1) Mg concentrations in serum vary with seasonal variations but not physiological
variations, (2) Fe and K concentrations in serum vary only with physiological variations, (3) the Cu concentration changes
not only pregnancy but also through some other hormonal changes not caused by pregnancy, (4) Ca, P, and Se concentrations
could vary with both physiologic and seasonal variations, (5) Zn, Na, and Cl were almost identical for both groups and altered
depending on neither season of the year nor the physiologic status, (6) both increased estradiol level and increased progesterone
level can raise Cu levels in serum, and (7) increased serum Ca concentrations are related with increased estradiol and decreased
P and Mg levels.
These observations suggest that seasonal and physiologic variations and sexual cycle have to be taken into consideration for
a correct ***DIRECT SUPPORT *** A02Q2015 00006 interpretation of elements status. If sheep are maintained at pasture conditions,
the nutritional requirements must be supplemented during certain periods. Otherwise, it is apparent that this will cause a
decline in the total performance of sheep and, consequently, economic lost. 相似文献
182.
Rohrich RJ Griffin JR Ansari M Beran SJ Potter JK 《Plastic and reconstructive surgery》2004,114(6):1405-16; discussion 1417-9
A retrospective analysis was performed on 1334 patients who underwent nasal reconstruction between 1986 and 2001. The senior author performed all reconstructions in this series after Mohs' histographic excisions. Only secondary reconstructions were performed without a preceding Mohs' excision. Methods of reconstruction, number of operations per patient, locations of defects, and complications were recorded. Using preoperative and postoperative photographs, aesthetic results were reviewed. Basal cell carcinoma was the most common lesion, followed by squamous cancer and melanoma. The average age of the patients was 51 years. Cancers most commonly arose on the dorsum, ala, and tip. Of 1334 cases, a 1.9 percent recurrence rate was documented. The average time between surgery and clinical recognition of recurrence was 39 months. All recurrent lesions were reexcised by the Mohs' technique. Eighty-one percent of reconstructions were completed in three or fewer stages. Seventy-five percent of reconstructions were completed in two stages. Primary dermabrasion or primary laserbrasion using carbon dioxide or erbium lasers was used in nearly every case. Early secondary dermabrasion or laserbrasion was used in a few cases where indicated. A 1.2 percent revision rate was noted (16 patients). Thirteen partial flap necroses required revision. Three patients experienced dehiscence at the donor site of paramedian forehead flaps. A preferred philosophy toward nasal reconstruction is described. The goal is to achieve optimal cosmetic and functional results while minimizing stages and resection of healthy tissue. Six core principles are advocated that guide efficient and successful nasal reconstruction: (1) maximal conservation of native tissue is advised; (2) reconstruction of the defect, not the subunit, is advised; (3) complementary ablative procedures, such as primary dermabrasion, enhance the final result and decrease the number of revisionary procedures; (4) primary defatting also decreases the number of revisionary procedures; (5) when possible, the use of axial pattern flaps is preferred; and (6) good contour is the aesthetic endpoint. 相似文献
183.
Chloe?KB?Mortimer Tansy?M?Peters Saheer?E?Gharbia Julie?MJ?Logan Catherine?ArnoldEmail author 《BMC microbiology》2004,4(1):31
Background
The fliC and fljB genes in Salmonella code for the phase 1 (H1) and phase 2 (H2) flagellin respectively, the rfb cluster encodes the majority of enzymes for polysaccharide (O) antigen biosynthesis, together they determine the antigenic profile by which Salmonella are identified. Sequencing and characterisation of fliC was performed in the development of a molecular serotyping technique. 相似文献184.
Amino acid sequence versus morphological data and the interordinal relationships of mammals 总被引:2,自引:0,他引:2
To a large extent, the mutual affinities of the mammalian orders continue
to puzzle systematists, even though comparative anatomy and amino acid
sequencing offer a massive data base from which these relationships could
potentially be adduced. In the present paper the consistency index--the
number of character states less the number of characters in a data set,
divided by the total number of changes in the character states on a
cladogram--was used to examine the relative resolving powers of recently
published morphological and molecular- sequence data. Consistency indices
were calculated for previously published alpha crystallin A chain and
myoglobin amino acid-sequence cladograms and for four original amino
acid-sequence cladograms (alpha crystallin A, myoglobin, and alpha and beta
hemoglobin); these were found to be comparable to the consistency indices
of morphologically based cladograms. Qualitative comparisons between the
morphologically based and molecularly based trees were also made; only
moderate congruence between the two was observed. Moreover, there was a
general lack of congruence between the cladograms specified by each of the
four proteins. Amino acid-sequence and morphological data agreed on the
placement of edentates as an early eutherian offshoot and on the grouping
of hyracoids, proboscideans, and sirenians. Otherwise there was only
limited congruence: morphology strongly supported the grouping of
lagomorphs and rodents and the alliance of pholidotes and edentates, but
sequence analyses did not. The placement of tubulidentates differed widely
among proteins. Morphology indicated the close association of sirenians
with proboscideans; proteins suggested a pairing of sirenians with
hyracoids. Sequence data did not identify many (morphologically
well-diagnosed) orders as monophyletic (e.g., Lagomorpha).(ABSTRACT
TRUNCATED AT 250 WORDS)
相似文献
185.
Molecular phylogenetics of Stenodermatini bat genera: congruence of data from nuclear and mitochondrial DNA 总被引:2,自引:1,他引:1
Van den Bussche RA; Baker RJ; Wichman HA; Hamilton MJ 《Molecular biology and evolution》1993,10(5):944-959
Within the tribe Stenodermatini the systematics of the complex of species
allied with the genus Artibeus has generated several alternative
phylogenetic hypotheses. The most recent treatment recognized four genera
(Artibeus, Dermanura, Enchisthenes, and Koopmania) and suggested that the
most recent common ancestor of these four genera would include the common
ancestor of all other currently recognized Stenodermatini genera except
Sturnira. To test this hypothesis, we examined an EcoRI-defined nuclear
satellite DNA repeat and 402 bp of DNA sequence variation from the
mitochondrial cytochrome b gene. Phylogenetic conclusions based on Southern
blot analyses, in situ hybridization, and mitochondrial DNA sequence data
indicate that Enchisthenes is not closely related to Dermanura, Artibeus,
or Koopmania and that Dermanura, Artibeus, and Koopmania shared a common
ancestor after diverging from the remainder of the Stenodermatini. If our
conclusions are correct, then justification for recognizing Dermanura and
Koopmania as generically distinct from Artibeus must be based on the
magnitude of difference that distinguishes each rather than on the
conclusion that to place them as congeneric with Artibeus creates a
paraphyletic taxon.
相似文献
186.
Multidimensional heteronuclear NMR studies have been applied to the
resonance assignment and conformational analysis of 13C-enriched
Neu5Acalpha2-3Galbeta1-4Glc. It is demonstrated that three-dimensional
ROESY-HSQC experiments provide through-space distance restraints which
cannot be observed with conventional homonuclear 1H techniques due to
resonance overlap. In particular, connectivities demonstrating the
existence of the "anti" conformation about the Galbeta1-4Glc glycosidic
linkage are unambiguously observed. It is shown that 13C isotopic
enrichment of the trisaccharide at a level >95% enables straightforward
measurement of trans-glycosidic 1H-13C and 13C-13C coupling constants and a
Karplus-type relation is derived for the latter. In total 15 conformational
restraints were obtained for the trisaccharide in aqueous solution, all of
which were in excellent agreement with theoretical parameters computed from
a 5 ns molecular dynamics simulation of the glycan.
相似文献
187.
Sanchez D; Ganfornina MD; Gutierrez G; Bastiani MJ 《Molecular biology and evolution》1998,15(4):415-426
Arthropodan hemocyanins, prophenoloxidases (PPOs), and insect hexamerins
form a superfamily of hemolymph proteins that we propose to call the AHPH
superfamily. The evolutionary and functional relationships of these
proteins are illuminated by a new embryonic hemolymph protein (EHP) that is
expressed during early stages of development in the grasshopper embryo. EHP
is a 78-kDa soluble protein present initially in the yolk sac content, and
later in the embryonic hemolymph. Protein purification and peptide
sequencing were used to identify an embryonic cDNA clone coding for EHP. In
situ hybridization identifies hemocytes as EHP-expressing cells. As deduced
from the cDNA clone, EHP is a secreted protein with two potential
glycosylation sites. Sequence analysis defines EHP as a member of the AHPH
superfamily. Phylogenetic analyses with all the currently available AHPH
proteins, including EHP, were performed to ascertain the evolutionary
history of this protein superfamily. We used both the entire protein
sequence and each of the three domains present in the AHPH proteins. The
phylogenies inferred for each of the domains suggest a mosaic evolution of
these protein modules. Phylogenetic and multivariate analyses consistently
group EHP with crustacean hemocyanins and, less closely, with insect
hexamerins, relative to cheliceratan hemocyanins and PPOs. The grasshopper
protein rigorously preserves the residues involved in oxygen binding,
oligomerization, and allosteric regulation of the oxygen transport
proteins. Although insects were thought not to have hemocyanins, we propose
that EHP functions as an oxygen transport or storage protein during
embryonic development.
相似文献
188.
Submerged cultures of the low-production strain ofTolypocladium inflatum DSM 63544 formed a mixture of cyclosporins (CS) consisting of CS-A, CS-B, "CS-3" and "CS-4". Glucose, sucrose and maltose
were highly favored for biomass production but provided a different physiological state necessary for CS biosynthesis. Not
only the magnitude of CS production but also the proportion of individual components of the CS mixture were affected by the
C source. Intensive CS synthesis was in correlation with the formation of CS-3. Lower yields of CS were accompanied by an
increased proportion of CS-A in the CS complex. The best specific production of CS was achieved on the glucose medium, the
highest yield of CS-A on the maltose medium. There was no remarkable relationship between the biomass formation and the intensity
of CS synthesis. 相似文献
189.
Analytical and preparative high-performance liquid chromatography of 3 phenazines and furonaphthoquinone derivative on resersed-phase
column are described. The mobile phase was methanol and water. The injected amount of the mixture was about 30 mg for a preparative
chromatographic run requiring 80 min. Substances were detected directly in the column effluent by UV detection. 相似文献
190.
Characterization of an amsacrine-resistant line of human leukemia cells. Evidence for a drug-resistant form of topoisomerase II 总被引:5,自引:0,他引:5
L A Zwelling M Hinds D Chan J Mayes K L Sie E Parker L Silberman A Radcliffe M Beran M Blick 《The Journal of biological chemistry》1989,264(28):16411-16420
HL-60/AMSA is a human leukemia cell line that is 100 times more resistant to the cytotoxic actions of the antineoplastic, topoisomerase II-reactive DNA intercalating acridine derivative amsacrine (m-AMSA) than is its parent HL-60 line. HL-60/AMSA cells are minimally resistant to etoposide, a topoisomerase II-reactive drug that does not intercalate. Previously we showed that HL-60 topoisomerase II activity in cells, nuclei, or nuclear extracts was sensitive to m-AMSA and etoposide, while HL-60/AMSA topoisomerase II was resistant to m-AMSA but sensitive to etoposide. Now we show that purified topoisomerase II from the two cell lines exhibits the same drug sensitivity or resistance as that in the nuclear extracts although the magnitude of the m-AMSA resistance of HL-60/AMSA topoisomerase II in vitro is not as great as the resistance of the intact HL-60/AMSA cells. In addition HL-60/AMSA cells are cross-resistant to topoisomerase II-reactive intercalators from the anthracycline and ellipticine families and the pattern of sensitivity or resistance to the cytotoxic actions of the various topoisomerase II-reactive drugs is paralleled by topoisomerase II-reactive drug-induced DNA cleavage and protein cross-link production in cells and the production of drug-induced, topoisomerase II-mediated DNA cleavage and protein cross-linking in isolated biochemical systems. In addition to its lowered sensitivity to intercalators, HL-60/AMSA differed from HL-60 in 1) the susceptibility of its topoisomerase II to stimulation of DNA topoisomerase II complex formation by ATP, 2) the catalytic activity of its topoisomerase II in an ionic environment chosen to reproduce the environment found within the living cell, and 3) the observed restriction enzyme pattern on a Southern blot probed with a cDNA for human topoisomerase II. These data indicate that an m-AMSA-resistant form of topoisomerase II contributes to the resistance of HL-60/AMSA to m-AMSA and to other topoisomerase II-reactive DNA intercalating agents. The drug resistance is associated with additional biochemical and molecular alterations that may be important determinants of cellular sensitivity or resistance to topoisomerase II-reactive drugs. 相似文献