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991.
Brát R Skorpil J Bárta J Suk M Schichel T 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2004,148(1):51-53
This case report demonstrates successful cardiopulmonary and cerebral resuscitation (CPCR) of a young male explored 15 hours following a suicide attempt (carbamazepine intoxication) in deep hypothermia (19 degrees C) with circulatory arrest. An extracorporeal circuit was used to rewarm the patient's blood. Weaning from extracorporeal circulation (ECC) was successful and without complications as was recovery from multiorgan dysfunction, severe rhabdomyolysis and carbamazepine intoxication. An excellent outcome was achieved without any neurological deficit at the time of discharge from the hospital. 相似文献
992.
Baick JW Yoon JH Namgoong S Söll D Kim SI Eom SH Hong KW 《Journal of microbiology (Seoul, Korea)》2004,42(2):111-116
It is known that Bacillus subtilis glutamyl-tRNA synthetase (GluRS) mischarges E. coli tRNA1 Gln with glutamate in vitro. It has also been established that the expression of B. subtilis GluRS in Escherichia coli results in the death of the host cell. To ascertain whether E. coli growth inhibition caused by B. subtilis GluRS synthesis is a consequence of Glu-tRNA1 Ghn formation, we constructed an in vivo test system, in which B. subtilis GluRS gene expression is controlled by IPTG. Such a system permits the investigation of factors affecting E. coli growth. Expression of E. coli glutaminyl-tRNA synthetase (GlnRS) also ameliorated growth inhibition, presumably by competitively preventing tRNA1 Gln misacylation. However, when amounts of up to 10 mM L-glutamine, the cognate amino acid for acylation of tRNA1 Gln, were added to the growth medium, cell growth was unaffected. Overexpression of the B. subtilis gatCAB gene encoding Glu-tRNAGln amidotransferase (Glu-AdT) rescued cells from toxic effects caused by the formation of the mischarging GluRS. This result indicates that B. subtilis Glu-AdT recognizes the mischarged E. coli GlutRNA1 Gln, and converts it to the cognate Gln-tRNA1 Gln species. B. subtilis GluRS-dependent Glu-tRNA1 Gln formation may cause growth inhibition in the transformed E. coli strain, possibly due to abnormal protein synthesis. 相似文献
993.
DuBok?ChoiEmail author KiAn?Cho Wol?Suk?Cha Seong?Ryeol?Ryu 《Biotechnology and Bioprocess Engineering》2004,9(3):171-178
Glucose alone was found to be the most effective carbon source for producing compactin. An initial glucose concentration of
40 g/L gave the highest compactin concentration of 250 mg/L. Among the various nitrogen sources, when 5 g/L of pharmamedia
and soybean meal as the sole nitrogen source were used, respectively, the compactin concentration was higher than 250 mg/L.
Especially, in the case of the mixture of 6 g/L of pharmamedia and 8 g/L of soybean meal, the compactin concentration was
400 mg/L. To select the best surfactant for effective compactin production, various surfactants were investigated. When Triton
X-100 was used, the maximum compactin concentration was 445 mg/L. With the initial concentration ranging from 1.5 to 2.0 g/L,
the compactin concentration was the highest at 465–450 g/L. The cell concentration was similar to that of the control without
the addition of Triton X-100. On the other hand, when the above 4.0 g/L of Triton X-100 were used, the cell concentration
decreased. Using the based results the continuous fed-batch cultures by adding the Triton X-100 were carried out for 10 days
in an air-lift bioreactor. When 1.5 g/L of Triton X-100 was added to the culture broth at 0, 4, and 8 days of culture, respectively,
the compactin production was increased with the increase of culture time. The maximum compactin concentration after 10 days
of culture was 1,200 mg/L, which was about 2.0-fold higher than that of the control without the addition of Triton X-100. 相似文献
994.
Sung?Hwan?Woo Jeung?Suk?Cho Baek?Seok?Lee Eun?Ki?KimEmail author 《Biotechnology and Bioprocess Engineering》2004,9(4):256-260
Melanin was decolorized by lignin peroxidase fromPhanerochaete chrysosporium. This decolorization reaction showed a Michaelis-Mentens type relationship between the decolorization rate and concentration
of two substrates: melanin and hydrogen peroxide. Kinetic constants of the decolorization reaction were 0.1 OD475/min (V
max) and 99.7 mg/L (K
m) for melanin and 0.08 OD475/min (V
max) and 504.9 μM (K
m) for hydrogen peroxide, respectively. Depletion of hydrogen peroxide interrupted the decolorization reaction, indicating
the essential requirement of hydrogen peroxide. Pulsewise feeding of hydrogen peroxide continued the decolorizing reaction
catalyzed by lignin peroxidase. These results indicate that enzymatic decolorization of melanin has applications in the development
of new cosmetic whitening agents. 相似文献
995.
Shiru?Jia Hongyu?Ou Guibing?Chen DuBok?ChoiEmail author KiAn?Cho Mitsuyasu?Okabe Wol?Suk?Cha 《Biotechnology and Bioprocess Engineering》2004,9(3):166-170
Gluconobacter oxydans that produces the cellulose was isolated. In order to confirm the chemical features of cellulose, various spectrophtometeric
analysis were carried out using electron microscopy, X-ray diffractogram, and CP/MAS13C NMR. The purified cellulose was found to be identical to that ofAcetobacter xylinum. For effective production of cellulose, the various carbon and nitrogen sources, mixture of calcium and magnesium ions, and
biotin concentration were investigated in flask cultures. Among the various carbon sources, glucose and sucrose were found
to be best for the production of cellulose, with maximum concentration of 2.41 g/L obtained when a mixture of 10 g/L of each
glucose and sucrose were used. With regard to the nitrogen sources, when 20 g/L of yeast extract was used, the maximum concentration
of bacterial cellulose was reached. The concentration of cellulose was increased with mixture of 2 mM of each Ca2+ and Mg2+. The optimum biotin concentration for the production of cellulose was in the range of 15 to 20 mg/L. At higher biotin concentration
(25–35 mg/L), the bacterial cellulose production was lower. 相似文献
996.
The role of cholesterol differs in the two compartments of the testis. In the interstitial tissue, cholesterol is necessary for the synthesis of testosterone, whereas in the seminiferous tubules, membrane cholesterol content in developing germ cells will influence the gametes' fertility. Here we evaluate the hormone-sensitive lipase (HSL) modulation of the cholesterol metabolism in each compartment of the testis. Two HSL immunoreactive bands of 104- and 108-kDa were detected in Western blots performed with polyclonal anti-human HSL antibodies in the interstitial tissue (ITf)- and seminiferous tubule (STf)-enriched fractions generated from testes harvested at 30-day intervals during puberty and, in the adult mink, during the annual seasonal reproductive cycle. Epididymal spermatozoa expressed a 104-kDa HSL isoform, and HSL was active in these cells. Immunolabeling localized HSL to interstitial macrophages; Sertoli cells, where its distribution was stage specific; spermatids; and the equatorial segment of spermatozoa. Total HSL protein levels, specific enzymatic activity, and free cholesterol (FC):esterified cholesterol (EC) ratios varied concomitantly in STf and ITf and reached maximal values in the adult during the period of maximal spermatogenic activity. In STf, HSL-specific activity correlated with FC:EC ratios but not with triglyceride levels. In STf, high HSL-specific activity occurred concomitantly with high FSH serum levels. In ITf, HSL-specific activity was high during periods of low serum prolactin levels and high serum testosterone levels. The results suggest that 1) modulation of cholesterol metabolism in individual testicular compartments may be regulated by HSL isoforms expressed by distinct cells; 2) interstitial macrophages may be part of a system involved in the synthesis of steroid hormones and in the recycling of sterols in the interstitium, whereas in the tubules, recycling could be ensured by Sertoli cells; 3) there is distinctive substrate preference for testicular HSL; and 4) HSL may be the only cholesterol esterase in this location. 相似文献
997.
Development of apoptosis-resistant dihydrofolate reductase-deficient Chinese hamster ovary cell line
Apoptosis-resistant dihydrofolate reductase-deficient CHO cell line (dhfr(-) CHO-bcl2) was developed by introduction of the bcl-2 gene into the dhfr(-) CHO cell line (DUKX-B11, ATCC CRL-9096) and subsequent selection of clones stably overexpressing Bcl-2 in the absence of selection pressure. When the dhfr(-) CHO-bcl2 cell line was used as a host cell line for development of a recombinant CHO (rCHO) cell line expressing a humanized antibody, it displayed stable expression of the bcl-2 gene during rCHO cell line development and no detrimental effect of Bcl-2 overexpression on specific antibody productivity. Taken together, the results obtained demonstrate that the use of an apoptosis-resistant dhfr(-) CHO cell line as the host cell line saves the effort of establishing an apoptosis-resistant rCHO cell line and expedites the development process of apoptosis-resistant rCHO cells producing therapeutic proteins. 相似文献
998.
Min B Kitabatake M Polycarpo C Pelaschier J Raczniak G Ruan B Kobayashi H Namgoong S Söll D 《Journal of bacteriology》2003,185(12):3524-3526
Two types of aspartyl-tRNA synthetase exist: the discriminating enzyme (D-AspRS) forms only Asp-tRNA(Asp), while the nondiscriminating one (ND-AspRS) also synthesizes Asp-tRNA(Asn), a required intermediate in protein synthesis in many organisms (but not in Escherichia coli). On the basis of the E. coli trpA34 missense mutant transformed with heterologous ND-aspS genes, we developed a system with which to measure the in vivo formation of Asp-tRNA(Asn) and its acceptance by elongation factor EF-Tu. While large amounts of Asp-tRNA(Asn) are detrimental to E. coli, smaller amounts support protein synthesis and allow the formation of up to 38% of the wild-type level of missense-suppressed tryptophan synthetase. 相似文献
999.
Inducible cyclooxygenase (COX-2) has been implicated in the processes of inflammation and carcinogenesis. Thus, the potential COX-2 inhibitors have been considered as anti-inflammatory or cancer chemopreventive agents. In this study, the methanolic extract of the cortex of Eugenia caryophyllata Thunberg (Myrtaceae) was found to potently inhibit the prostaglandin E(2) production in lipopolysaccharide (LPS)-activated mouse macrophage RAW264.7 cells (98.3% inhibition at the test concentration of 10 microg/ml). Further, hexane-soluble layer was the most active partition compared to ethyl acetate, n-butanol, and water-soluble parts. By bioassay-guided fractionation of hexane-soluble partition, eugenol was isolated and exhibited a significant inhibition of PGE(2) production (IC(50) = 0.37 microM). In addition, eugenol suppressed the cyclooxygenase-2 (COX-2) gene expression in LPS-stimulated mouse macrophage cells. On the line of COX-2 playing an important role in colon carcinogenesis further study was designed to investigate the effect of eugenol on the growth and COX-2 expression in HT-29 human colon cancer cells. Eugenol inhibited the proliferation of HT-29 cells and the mRNA expression of COX-2, but not COX-1. This result suggests that eugenol might be a plausible lead candidate for further developing the COX-2 inhibitor as an anti-inflammatory or cancer chemopreventive agent. 相似文献
1000.
Total ear reconstruction using the omental free flap technique was performed on five patients who presented with a devascularized temporoparietal region. The main indication for this technique was unavailability of the contralateral temporoparietal fascia in those requesting autogenous auricular reconstruction. There were no microvascular failures in the procedures conducted. In one case there was a partial loss of the transferred omentum, which resulted from an inadequate omental tailoring. A normal convoluted auricle was obtained after multistage debulking operations and meticulous postoperative molding. The average follow-up period was 3.4 years. Final aesthetic results were graded as satisfactory in four patients and poor in one patient. 相似文献