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41.
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43.
Madhava Das Mehrotra 《Mycopathologia》1964,24(3):259-264
Summary The utilization of mixtures of monosaccharides byBlakeslea trispora
Thaxter,Choanephora circinans (Naganish &Kawakami)Hesseltine &Benjamin,Gilbertella persicaria var.indica
Mehrotra &Mehrotra andHelicostylum piriforme
Bainier was studied. The effect of sorbose on the utilization of other sugars present in the mixtures was also studied. It was found that all the mixtures of sugars in combination with asparagine or ammonium chloride were valueless for all the organisms exceptHelicostylum piriforme. Growth ofHelicostylum piriforme on the mixtures with asparagine as the nitrogen source was better than on the mixtures with ammonium chloride as the source of nitrogen. Asparagine being a favourable source counteractecd sorbose inhibition, while ammonium chloride failed to do so. On the other hand, both of the nitrogen sources failed to counteract sorbose inhibition in the rest of the organisms. None of the organisms could finish sorbose and rhamnose from any of the mixtures within the specified period. 相似文献
44.
Misra AP Mathad VT Raj K Bhaduri AP Tiwari R Srivastava A Mehrotra PK 《Bioorganic & medicinal chemistry》2001,9(11):2763-2772
Structural modifications in iridoid glycosides and evaluation of their efficacy on adhering capability (in vitro) of immature hamster uterine epithelial cells to the substratum have been studied. Out of 31, eight compounds in vitro, five compounds in utero and two in vivo showed adhesion/implantation preventing activity, respectively. The results provide an indication for further exploration in the line of development of anti-adhesive agents. 相似文献
45.
Response of benzoate along with phenol to different anaerobic inocula has been investigated in batch reactors. In Phase I, the anaerobic biodegradability of benzoate and phenol were evaluated using (a) washed acclimatized granular sludge (WAGS) collected from a passive phenol fed bench-scale up-flow anaerobic sludge blanket reactor (UASBR) and (b) unacclimatized flocculent sludge (UFS) from a UASB based sewage treatment plant (STP). The effect of varying concentrations of benzoate has been investigated in Phase II using acclimatized granular sludge (AGS) from a bench-scale UASBR. Extent of degradation of benzoate was more than the phenol. Increasing benzoate COD from 2500 to 11,700mg/L, resulted in decrease in (i) rate constant, k from 0.79 to 0.11/d and (ii) ultimate biochemical methane potential (microb, g CH4-COD formed/g benzoate COD) from 84% to 60%. Temporal trend conforming to logistic S-curve indicated stressed conditions at higher benzoate concentration. Benzoate degradation was found to be sensitive to nature as well as quantity i.e. food to microorganism (F/M) of inocula used. 相似文献
46.
Albino rats were administered estogen, progesterone or testosterone daily for 4 weeks to study the ponderal, histological and biochemical changes in the cervix and vagina. Stimulatory signs with increased weight, thickening, keratinization and desquamation of the surface epithelium, loose and edematous stroma were descernible in both the organs under estrogen and to some extent under testosterone but not under progesterone. However, progesterone altered the squamous type of vaginal epithelium to thin layers made up of uboidal cells. Metaplastic changes characterized the epithelium under testosterone. Biochemical responses of the 2 organs were often found to differ quantitatively and qualitatively under identical hormonal conditions. Statistical analyses are presented. Possible reasons for the differential behavior of the 2 organs are discussed. 相似文献
47.
48.
Reactions of alkanolamines [R1R2NXOH; R1 = H, CH3, C2H5; R2 = H, CH3, C2H5 and X = -CH2CH2-, -CH2CH2CH2-, -CH2CHCH3, -C6H4CH2CH2-] with aluminium isopropoxide in different molar ratios (1 to 3) yield compounds of the type Al(OPri)3?n(OXNR1R2)n, where ‘n’ can be 1, 2 and 3. Most of the derivatives are distillable liquids, soluble in common organic solvents and susceptible to hydrolysis even by atmospheric moisture. The new derivatives are characterized by elemental analysis, IR and 1H NMR spectra. Molecular weight measurements of Al(OPri)3?n(OXNR1R2)n reveal them to be tetrameric in nature. 相似文献
49.
Drew M. Dolino Swarna S. Ramaswamy Vasanthi Jayaraman 《Journal of visualized experiments : JoVE》2014,(91)
Luminescence Resonance Energy Transfer, or LRET, is a powerful technique used to measure distances between two sites in proteins within the distance range of 10-100 Å. By measuring the distances under various ligated conditions, conformational changes of the protein can be easily assessed. With LRET, a lanthanide, most often chelated terbium, is used as the donor fluorophore, affording advantages such as a longer donor-only emission lifetime, the flexibility to use multiple acceptor fluorophores, and the opportunity to detect sensitized acceptor emission as an easy way to measure energy transfer without the risk of also detecting donor-only signal. Here, we describe a method to use LRET on membrane proteins expressed and assayed on the surface of intact mammalian cells. We introduce a protease cleavage site between the LRET fluorophore pair. After obtaining the original LRET signal, cleavage at that site removes the specific LRET signal from the protein of interest allowing us to quantitatively subtract the background signal that remains after cleavage. This method allows for more physiologically relevant measurements to be made without the need for purification of protein. 相似文献
50.
Fourier transform ir spectra have been recorded for three 310‐helical and one α‐helical pentapeptides containing dehydrophenylalanine, in a thin solid film, in order to find marker bands for various secondary structures encountered in peptides containing dehydroaminoacids. The peptide solutions were deposited and dried as thin film on zinc selenide crystal surface. This convenient sampling method has provided reliable estimates of peptide secondary structure in solid state. Detailed vibrational assignments in the spectral region between 1200–1700 cm−1 are reported. In this region, peptide amide I, II, and III vibrations occur. Spectra–structure correlation has been presented based on the amide modes. Comparison of the ir spectra with available crystal structure data provides qualitative support for assignments of ir bands to 310‐helical structure and α‐helical structure in dehydrophenylalanine containing pentapeptides. Band frequency assignments for 310‐helical conformation are consistent for all three peptides. All the assignments agree closely with the theoretical predictions. The spectral differences between 310‐helical peptides and the α‐helical peptide have been highlighted. These findings demonstrate that a method based on ir spectroscopy can be developed for a useful approximation of three‐dimensional structure of dehydropeptides in solid state. © 1999 John Wiley & Sons, Inc. Biopoly 50: 595–601, 1999 相似文献