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Immune activation is implicated in the etiology of preterm labor, but little is known about macrophage number or distribution in the uterus or cervix at term. This study tested the hypothesis that macrophages migrate into the reproductive tract before the onset of parturition. Paraffin-embedded sections from the mid-uterine horn and cervix of C3/HeN mice on Days 15 and 18 of pregnancy, the day of birth (Day 19), and 1 day postpartum were stained with a pan-macrophage marker to analyze cell numbers and distribution. During pregnancy, uterine macrophages were dispersed in endometrium, usually associated with vasculature and subluminal epithelium. In myometrium, macrophages were clustered in stromal connective tissue; near term and postpartum, cells appeared to surround the muscle bundles. Total macrophage numbers were increased on Day 15 relative to those in nonpregnant controls, declined before birth, and increased postpartum. In the cervix, macrophages congregated in subepithelium, often perivascular or near ganglia. Macrophage numbers in the cervix peaked on Day 18, then declined to nonpregnant levels by the day after birth. Thus, macrophage numbers in the uterus were inversely related to those in the cervix. These findings raise the possibility that macrophages and their products may be involved in uterine contractility and cervical remodeling during the processes of parturition. 相似文献
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The effects of 50 microM lanthanum (La3+) on the contractile force, rate and coronary flow of rat hearts perfused with solutions containing 2.5, 5, 7.5 mM calcium (Ca2+) have been investigated. La3+ produced a rapid and marked decrease in contractile force within 1-3 min ("early La(3+)-effect"). The inhibition of contractility by La3+ was reduced progressively when the Ca2+ ion concentration in the perfusion fluid was raised from 2.5 to 7.5 mM. However, after 10-80 min of La3+ perfusion the contractile force was increased significantly ("late La(3+)-effect"). Elevation of Ca2+ during exposure to La3+ increased its effect. During the late La(3+)-effect, a marked decrease in heart rate and a significant increase in time to reach peak tension, time for half relaxation and twitch duration was observed. High concentrations of perfusate Ca2+ decreased the chronotropic response to La3+, in contrast, elevated Ca2+ potentiated La(3+)-induced increase in time to reach peak tension, time for half relaxation and twitch duration. La3+ produced a significant decrease in coronary flow. High Ca2+ augmented the decrease coronary flow. The findings indicate that La3+ may produce marked effects on myocardial function. High extracellular Ca2+ reduces the La(3+)-induced initial decrease in force of contraction, but potentiates the late increase in contractile force by La3+. Elevated external Ca2+ also increases the effects of La3+ on twitch parameters, heart rate and coronary flow. 相似文献
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Xuehong Ren Akin Akdag Hasan B. Kocer S.D. Worley R.M. Broughton T.S. Huang 《Carbohydrate polymers》2009,78(2):220-226
A new N-halamine precursor, 3-(2,3-dihydroxypropyl)-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione (TTDD diol), was synthesized and bonded onto cotton fabrics. Fabrics with variable amounts of chlorine loading were prepared by using several concentrations of TTDD diol. A second N-halamine precursor, 3-(3-triethoxysilylpropyl)-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione (TTDD siloxane), was also synthesized and bound to cotton for comparison purposes. The coated cotton fabrics contained two types of N–Cl moieties after chlorination of the amine and amide groups. Swatches with variable chlorine loadings were challenged with Staphylococcus aureus and Escherichia coli O157:H7 as a function of contact time. The biocidal test results showed that the chlorine loadings and surface hydrophobicities influenced the antimicrobial efficacies. The chlorinated swatches have also been employed to oxidize the simulant of chemical mustard to the less toxic sulfoxide derivative. 相似文献
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Erkan Yurtcu Akin Yilmaz Zubeyde Ozkurt Emine Kolukisa Murat Yilmaz Hatice Keles Mehmet Ali Ergun Ilhan Yetkin Adnan Menevse 《Biochemical genetics》2009,47(3-4):295-300
Obesity is a complex disease caused by both genetics and environmental factors. Melanocortin-4 receptor (MC4R) (MIM 155541) gene polymorphisms were reported to be the cause of monogenic obesity in humans. We studied three polymorphisms (Val50Met, Val103Ile, and Ser58Cys) and a mutation (Asn274Ser) of the MC4R gene in 203 obese patients and in 110 healthy subjects in the Turkish population. A high incidence of Val103Ile and Val50Met polymorphisms as well as the Asn274Ser mutation was found in the obese patients, whereas no significant correlation was found regarding the Ser58Cys polymorphism. We conclude that there is a concordance between the polymorphisms (Val103Ile, Val50Met, Ser58Cys) that were first studied in the Turkish population with obesity. 相似文献
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Jianxia Kang Yuanli Song Akin Sevinc Leslie W.-M. Fung 《Cellular & molecular biology letters》2010,15(1):46-54
Spectrin tetramerization is important for the erythrocyte to maintain its unique shape, elasticity and deformability. We used
recombinant model proteins to show the importance of one residue (G46) in the erythroid α-spectrin junction region that affects
spectrin tetramer formation. The G46 residue in the erythroid spectrin N-terminal junction region is the only residue that
differs from that in non-erythroid spectrin. The corresponding residue is R37. We believe that this difference may be, at
least in part, responsible for the 15-fold difference in the equilibrium constants of erythroid and non-erythroid tetramer
formation. In this study, we replaced the Gly residue with Ala, Arg or Glu residues in an erythroid α-spectrin model protein
to give G46A, G46R or G46E, respectively. We found that their association affinities with a β-spectrin model protein were
quite different from each other. G46R exhibited a 10-fold increase and G46E exhibited a 16-fold decrease, whereas G46A showed
little difference, when compared with the wild type. The thermal and urea denaturation experiments showed insignificant structural
change in G46R. Thus, the differences in affinity were due to differences in local, specific interactions, rather than conformational
differences in these variants. An intra-helical salt bridge in G46R may stabilize the partial domain single helix in α-spectrin,
Helix C’, to allow a more stable helical bundling in the αβ complex in spectrin tetramers. These results not only showed the
importance of residue G46 in erythroid α-spectrin, but also provided insights toward the differences in association affinity
between erythroid and non-erythroid spectrin to form spectrin tetramers. 相似文献
50.
A gram-negative, moderately halophilic bacterium was isolated from ?amalt? Saltern area, located in the Aegean Region of Turkey. Analysis of its 16S rRNA gene sequence and physiological characteristics showed that this strain belonged to the genus Halomonas ; hence, it was designated as Halomonas sp. strain AAD12. The isolate tolerated up to 800 mg?L(-1) phenol; however, at elevated concentrations, phenol severely retarded cell growth. The increase in lag phase with increasing phenol concentrations indicated that the microorganism was undergoing serious adaptative changes. To understand the physiological responses of Halomonas sp. strain AAD12 to phenol, a 2-dimensional electrophoresis approach combined with mass spectrometric analysis was used. This approach showed that the expression of 14 protein spots were altered as phenol concentration increased from 200 to 800 mg?L(-1). Among the identified proteins were those involved in protein biosynthesis, energy, transport, and stress metabolism. So far, this is the first study on phenolic adaptation of a gram-negative, moderately halophilic bacteria using proteomic tools. The results provided new insights for understanding the general mechanism used by moderately halophilic bacteria to tolerate phenol and suggested the potential for using these microorganisms in bioremediation. 相似文献