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排序方式: 共有376条查询结果,搜索用时 14 毫秒
21.
Adolf Baumgartner Jingly Fung Weier Heinz-Ulrich G Weier 《The journal of histochemistry and cytochemistry》2006,54(12):1363-1370
In research as well as in clinical applications, fluorescence in situ hybridization (FISH) has gained increasing popularity as a highly sensitive technique to study cytogenetic changes. Today, hundreds of commercially available DNA probes serve the basic needs of the biomedical research community. Widespread applications, however, are often limited by the lack of appropriately labeled, specific nucleic acid probes. We describe two approaches for an expeditious preparation of chromosome-specific DNAs and the subsequent probe labeling with reporter molecules of choice. The described techniques allow the preparation of highly specific DNA repeat probes suitable for enumeration of chromosomes in interphase cell nuclei or tissue sections. In addition, there is no need for chromosome enrichment by flow cytometry and sorting or molecular cloning. Our PCR-based method uses either bacterial artificial chromosomes or human genomic DNA as templates with alpha-satellite-specific primers. Here we demonstrate the production of fluorochrome-labeled DNA repeat probes specific for human chromosomes 17 and 18 in just a few days without the need for highly specialized equipment and without the limitation to only a few fluorochrome labels. 相似文献
22.
The influence of polymorphism of -493G/T MTP gene promoter and metabolic syndrome on lipids, fatty acids and oxidative stress 总被引:1,自引:0,他引:1
Zák A Jáchymová M Tvrzická E Vecka M Duffková L Zeman M Slabý A Stanková B 《The Journal of nutritional biochemistry》2008,19(9):634-641
The aim of this study was to investigate the effect of the microsomal triglyceride transfer protein (MTP) -493G/T polymorphism on clinical and biochemical parameters in relation to the presence of metabolic syndrome (MS). A group of 270 participants, 143 men and 127 women [50 men/36 women fulfilled the International Diabetes Federation (IDF) criteria of MS], was categorized on the basis of the MTP -493G/T polymorphism: GG homozygotes (Group GG) and carriers of the T allele (Group TT+TG). In men with MS, the presence of the T allele was associated with elevated concentrations of plasma insulin (by 48%, P<.01) and nonesterified fatty acids (by 49%, P<.05); homeostasis model assessment for insulin resistance index was higher by 64% (P<.05). Carriers of the T allele were further characterized by elevated plasma concentrations of total cholesterol (by 14%, P<.05) and by increased triglycerides in plasma (by 95%, P<.01) and in very low-density lipoprotein (by 106%, P<.01). They also had lower concentrations of n-6 polyunsaturated fatty acids in plasma phospholipids (by 3.5%, P<.05), lower Delta5-desaturase activities (by 18%, P<.05) and elevated concentrations of conjugated dienes in low-density lipoprotein (by 29%, P<.01). No significant differences between Groups GG and TT+TG were found in men without MS and in women with and without MS. Our results imply evidence for interactive effects of genetic, metabolic and gender-specific factors on several components of metabolic syndrome, which can increase the risk for cardiovascular disease. 相似文献
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Jonathan R. Deeds Daniel E. Terlizzi Jason E. Adolf Diane K. Stoecker Allen R. Place 《Harmful algae》2002,1(2)
The goal of this study was to test for, and partially characterize, toxic activity associated with the dinoflagellate Karlodinium micrum. Since 1996, three fish kill events associated with blooms of K. micrum have occurred at HyRock Fish Farm, an estuarine pond aquaculture facility raising hybrid striped bass on the Chesapeake Bay, MD, USA. Using an assay based on the lysis of rainbow trout erythrocytes, cultures of a Chesapeake Bay isolate of K. micrum have been shown to produce toxic substances which are released upon cell disturbance or damage. The LC50 for hemolysis of a sonicated cell suspension was 2.4×104 cells ml−1, well within the range of cell concentrations observed associated with fish kills. The toxic activity from K. micrum cells and culture filtrates was traced to two distinct fractions that co-elute with polar lipids. The LC50 for hemolysis of the larger of these two fractions (Tox A) was 284 ng ml−1 while the LC50 of the second, smaller, fraction (Tox B) was 600 ng ml−1. For comparison, the LC50 for the standard hemolysin saponin was 3203 ng ml−1. At concentrations of 800 and 2000 ng ml−1, respectively, Tox A was further shown to be ichthyotoxic to zebrafish (Danio rerio) larvae (80% mortality), and cytotoxic to a mammalian GH(4)C(1) cell line (100% LDH release). At a concentration of 600 ng ml−1 Tox B was shown to be cytotoxic to a mammalian GH(4)C(1) cell line (>30% LDH release), but not ichthyotoxic to zebrafish (D. rerio) larvae up to a concentration of 250 ng ml−1. Although treatment with either algicidal copper or potassium permanganate caused significant lysis of K. micrum cells (>70%), toxic activity was released after treatment with copper and eliminated following treatment with potassium permanganate. This observation in cultures is consistent with observations made at HyRock Fish Farm where significantly higher mortality was observed following treatment of a K. micrum bloom with copper sulfate compared to treatment with potassium permanganate. This study represents the first direct evidence of the toxicity of K. micrum isolated from the Chesapeake Bay. 相似文献
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27.
Underground Vendobionta From Namibia 总被引:2,自引:0,他引:2
The late Precambrian fossils from Namibia have generally been regarded as soft-bodied organisms whose three-dimensional preservation resulted from smothering in fluidized sand. The sedimentological context of Pteridinium and Namalia within a sandstone bed, however, allows us to distinguish between two taphocoenoses: (1) winnowed, laterally collapsed, current-transported specimens accumulated as a lag deposit of turbidite-like flows, and (2) specimens 'floating' in the top part of an event bed with their vanes extending upwards to the upper bedding surface. The second taphocoenosis is interpreted as an in situ preserved 'infaunal' community. The immobile underground life habit and the bizarre modes of growth of Pteridinium and Namalia do not fit any extinct or modern group of multicellular organisms. Similar statements can be made for Ernietta and Rangea , thus reviving the Vendobionta hypothesis. 相似文献
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29.
Adolf Portmann 《Zoomorphology》1926,5(3):406-423
Ohne ZusammenfassungBuchstabenerklärung zu den Abbildungen
A
After
-
Av
vordere Aorta
-
Ah
hintere Aorta
-
Au
Augen
-
Da
äußere Dottersack
-
Di
innerer Dottersack
-
De
Dotterepithel
-
Do
oberes Dottergefäß
-
Du
unteres Dottergefäß
-
GC
Cerebralganglion
-
GO
Optisches Ganglion
-
GP
Pedalganglion
-
GV
Visceralganglion
-
Gi
Giftdrüse (meist Speicheldrüse genannt)
-
K
Kiemen
-
KH
Kiemenherzen
-
L
Leber
-
M
Mund
-
Md
Mitteldarm
-
Mh
Mantelhöhle
-
Ml
Mantel
-
SD
Sinus des äußeren Dottersacks
-
Sh
hinterer Sinus
-
SK
Kopfsinus
-
SSt
Statocystensinus
-
St.
Statocysten
-
Sch
Schlundkopf
-
Ss
Schalensack
-
T
Tentakel
-
Ti
Tintendrüse
-
Tr
Trichter
-
V
Ventrikel
-
Vd
Vorderdarm
-
VH
Hohlvene
-
VM
Mantelvene
-
VS
Venenschenkel 相似文献
30.