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991.
A new lignan characterised as (-)-4-hydroxy-2,6-di-(4′-hydroxy-3′-methoxy)phenyl-3,7-dioxabicyclo-(3.3.0)octane along with n-10-nonacosanol, scopoletin, syringic acid, β-sitosterol and its glucoside, has been isolated from the aerial parts of Lonicera hypoleuca. The stereochemistry of the lignan has been established by its spectroscopic analysis and those of its derivatives, and by its conversion to (+)-pinoresinol. β-Sitosterol-β-D-glucoside displayed good spasmolytic activity. 相似文献
992.
Connexin 50 mutation in a family with congenital "zonular nuclear" pulverulent cataract of Pakistani origin 总被引:16,自引:0,他引:16
Vanita Berry Donna Mackay Shagufta Khaliq Peter J. Francis Abdul Hameed Khalid Anwar S. Qasim Mehdi Richard J. Newbold Alex Ionides Alan Shiels Tony Moore Shomi S. Bhattacharya 《Human genetics》1999,105(1-2):168-170
Inherited cataract is a clinically and genetically heterogeneous disease that most often presents as a congenital autosomal
dominant trait. Here we report linkage of a three-generation family of Pakistani origin with autosomal dominant cataract "zonular
nuclear" pulverulent type (CZNP) on chromosome 1q21.1. Genome wide-linkage analysis excluded all the known cataract loci except
on chromosome 1q. Significantly positive 2-point lod score values (Z=3.01 at θ=0) were obtained for markers D1S305 and D1S2721, which are known to flank the gene for connexin 50 (Cx50) or gap
junction protein alpha-8 (Gja8). Previously a mutation in this gene has been reported in a British family with zonular pulverulent cataract (CZP).Here we
describe a second mutation (E48K) in connexin 50 that confirms the involvement of this gene in cataractogenesis.
Electronic Publication 相似文献
993.
Ruojie Zhang Zipei Zhang Taha Kumosani Sawsan Khoja Khalid Omer Abualnaja David Julian McClements 《Food biophysics》2016,11(2):154-164
Nanoemulsion-based delivery systems are finding increasing use in food, pharmaceutical, agrochemical, and personal care applications due to their ability to increase the stability and/or activity of lipophilic functional components. In this study, a low-energy homogenization method (spontaneous emulsification) was used to encapsulate β-carotene in nanoemulsions. The main objective was to optimize lipid phase composition to form stable nanoemulsions that would effectively enhance β-carotene bioavailability. Lipid phase composition was varied by mixing long chain triglycerides (LCT) with medium chain triglycerides (MCT) or flavor oil (orange oil). LCT was added to promote bioaccessibility, whereas MCT or orange oil was added to facilitate nanoemulsion formation. Our hypothesis was that an optimum level of LCT is required to form stable nanoemulsions with good bioaccessibility characteristics. Stable nanoemulsions could be formed at LCT-to-orange oil ratios of 1:1 (d 32 = 109 nm) and at LCT-to-MCT ratios of 1:2 (d 32 = 145 nm). Thus, higher LCT loading capacities and smaller droplet sizes could be obtained using orange oil. The influence of oil composition on the potential gastrointestinal fate of the nanoemulsions was studied using a simulated gastrointestinal tract (GIT) consisting of mouth, stomach, and small intestine phases. The transformation and bioaccessibility of β-carotene in the GIT was highly dependent on lipid phase composition. In particular, β-carotene bioaccessibility increased with increasing LCT level due to greater solubilization in mixed micelles. These results are useful for optimizing the design of nanoemulsion-based delivery systems for encapsulation and release of lipophilic nutraceuticals and pharmaceuticals. 相似文献
994.
Abdelnasser S. S. Ibrahim Ahmed M. El-Toni Ali A. Al-Salamah Khalid S. Almaary Mohamed A. El-Tayeb Yahya B. Elbadawi Garabed Antranikian 《Bioprocess and biosystems engineering》2016,39(5):793-805
Alkaline protease from alkaliphilic Bacillus sp. NPST-AK15 was immobilized onto functionalized and non-functionalized rattle-type magnetic core@mesoporous shell silica (RT-MCMSS) nanoparticles by physical adsorption and covalent attachment. However, the covalent attachment approach was superior for NPST-AK15 protease immobilization onto the activated RT-MCMSS-NH2 nanoparticles and was used for further studies. In comparison to free protease, the immobilized enzyme exhibited a shift in the optimal temperature and pH from 60 to 65 °C and pH 10.5–11.0, respectively. While free protease was completely inactivated after treatment for 1 h at 60 °C, the immobilized enzyme maintained 66.5 % of its initial activity at similar conditions. The immobilized protease showed higher k cat and K m , than the soluble enzyme by about 1.3-, and 1.2-fold, respectively. In addition, the results revealed significant improvement of NPST-AK15 protease stability in variety of organic solvents, surfactants, and commercial laundry detergents, upon immobilization onto activated RT-MCMSS-NH2 nanoparticles. Importantly, the immobilized protease maintained significant catalytic efficiency for ten consecutive reaction cycles, and was separated easily from the reaction mixture using an external magnetic field. To the best of our knowledge this is the first report about protease immobilization onto rattle-type magnetic core@mesoporous shell silica nanoparticles that also defied activity-stability tradeoff. The results clearly suggest that the developed immobilized enzyme system is a promising nanobiocatalyst for various bioprocess applications requiring a protease. 相似文献
995.
Problem Management Plus (PM+): pilot trial of a WHO transdiagnostic psychological intervention in conflict‐affected Pakistan 下载免费PDF全文
996.
Sengupta Amitabha Wu Qiongli Grundke-Iqbal Inge Iqbal Khalid Singh Toolsee J. 《Molecular and cellular biochemistry》1997,167(1-2):99-105
Tau protein from Alzheimer disease (AD) brain is hyperphosphorylated by both proline-dependent protein kinases (PDPKs) and non-PDPKs. It is presently unclear how PDPKs and non-PDPKs interact in tau hyperphosphorylation. Previously we have shown that non-PDPKs can positively modulate the activity of a PDPK (GSK-3) in tau phosphorylation (Singh et al. (1995) FEBS Lett. 358, 267-272). In this study we have investigated whether (A) non-PDPKs can also modulate the activity of the PDPK, cdk5, (B) a PDPK can modulate the activities of another PDPK, as well as non-PDPKs. We found that, like GSK-3, the activity of cdk5 is stimulated if tau were first prephosphorylated by any of several non-PDPKs (A-kinase, C-kinase, CK-1, CaM-kinase II). Prephosphorylation of tau by cdk5 stimulated both the rate and extent of a subsequent phosphorylation catalyzed by GSK-3. Under these conditions thr 231 phosphorylation was especially enhanced (9-fold). No significant stimulation of phosphorylation was obser ved when the order of these kinases was reversed (i.e. GSK-3 followed by cdk5). By contrast, prephosphorylation of tau by cdk5 served to inhibit subsequent phosphorylation catalyzed by C-kinase and CK-1, but not by A-kinase or CaM-kinase II. Our results suggest that in tau hyperphosphorylation in AD brain, cdk5-catalyzed phosphorylation may serve to up-regulate the activity of GSK-3 and down-regulate the activities of C-kinase and CK-1. (Mol Cell Biochem 167: 99-105, 1997) 相似文献
997.
Involvement of Trihydroxyconjugated Bile Salts in Cholesterol Assimilation by Bifidobacteria 总被引:6,自引:0,他引:6
To determine the conditions of cholesterol assimilation,
various strains of Bifidobacterium species were cultured in the
presence of cholesterol and bile salts. During culturing, Bifidobacterium
breve ATCC 15700 assimilates cholesterol in the presence of oxgall at pH
values lower than 6. This strain was selected to study the influence of
conjugated (taurocholic acid) and deconjugated (cholic acid) bile salts on
cholesterol assimilation. B. breve ATCC 15700 assimilated cholesterol
(up to 51%) when cultures were undertaken in the presence of
taurocholic acid, whereas less than 13% of the initial amount of
cholesterol was measured in the cells in the presence of cholic acid.
Cultured in the presence of six individual di- or trihydroxyconjugated bile
salts, bifidobacteria strains assimilated cholesterol. This assimilation
appeared to be more important in the presence of trihydroxyconjugated bile
salts (tauro- and glycocholic acids). It is concluded that
trihydroxyconjugated bile salts are involved in the assimilation of
cholesterol by bifidobacteria.
Received: 20 June 1996 / Accepted: 19 July 1996 相似文献
998.
Summary Feasibility for bacterial leaching of two different copper ores from Pakistan was investigated with locally isolated, acidophilic thiobacilli in shake flask culture at 28±2°C. After a lag period of 16 d,Thiobacillus thiooxidans solubilized up to 19% of copper present in chalcopyrite ore in 14 d before entering stationary phase. In oxidized copper ore amended with chalcopyrite ore and supplemented with sulphur to provide an energy source forT. ferrooxidans, the pH dropped as a result of bacterial growth and was accompanied by copper solubilization. The highest copper release, 61% of total, occurred in flasks having oxidized copper ore, sulphur and calcopyrite (111, by weight) and inoculated withT. ferrooxidans. Supplementation used in these tests resulted in nearly six times more solubilization as compared to tests conducted without supplementation.
Resumen Se ha estudiado la posibilidad de realizar un lixiviado mediante bacterias de dos minerales de cobre del Pakistan. Las bacterias utilizadas son cepas, aísladas localmente, de tiobacilos acidófilos que se hacen crecer en un medio líquido en agitación a 28±2°C. Después de una fase lag de 16 dThiobacillus thiooxidans solubilizó hasta 19% del cobre presente en la calcopirita en 14 d, antes de alcanzar la fase estacionaria. El mineral de cobre oxidado se modificó con calcopirita y se suplementó con azufre afín de sumministrar una fuente de energía paraT. ferrooxidans, a resultas del crecimiento bacteriano el pH disminuyó solubilizándose cobre. La mayor cantidad de cobre sulubilizado se cencontró en frascos con mineral de cobre oxidado, azufre y calcopirita (111 en peso) e inoculados conT. ferrooxidans. La adición de suplementos incrementó 6 veces la solubilización comparada con la obtenida en ensayos sin adición de suplementos.
Résumé On a testé la faisabilité de la lixiviation bactérienne de deux minerais différents de cuivre du Pakistan au moyen de thiobacilli acidophiles,isolés localement, en culture en flaçons agités à 28 ±2°C. Après une période de latence de 16 jours,Thiobacillus thiooxidans a solubilisé jusqu'à 19% du cuivre présent dans le minerai de chalcopyrite en 14 jours avant d'entrer en phase stationnaire de croissance. Dans un minerai de cuivre amendé par le minerai de chalcopyrite et additionné de soufre de manière à fournir une source d'énergie pourT. ferrooxidans, le pH a baissé comme suite de la croissance bactérienne, ce qui a entraîné la solubilisation du cuivre. La libération la plus élevée de cuivre, 61% au total, a eu lieu dans les flaçons qui avaient à oxyder le minerai de cuivre, le soufre et la chalcopyrite oans les proportions de 111 en poids, et qui avaient été inoculés parT. ferrooxydans. La supplémentation effectuée dans ces tests a eu pour effet de dissoudre six fois plus de cuivre que dans les tests conduits sans supplémentation.相似文献
999.
Mohammad Shafeeq D. Kokub Z. M. Khalid A. M. Khan Kauser A. Malik 《World journal of microbiology & biotechnology》1989,5(4):505-510
Summary A bacterium isolated from an oil spillage sample and identified asPseudomonas aeruginosa degraded hexadecane and heptadecane by 47% and 58% with 9% and 12% of total carbon from the respective substrates being liberated as CO2. With octadecane and nonadecane as substrates, 73% and 60% were biodegraded while 27% and 25% of total carbon was evolved as CO2, respectively. Production of biosurfactant by this bacterium was studied using hexadecane 5% (v/v) as substrate. The surface tension of spent culture medium, as well as the supernatant, was 30 mN/m compared to 71 mN/m for water. When the supernatant was mixed with hexadecane (15, v/v) a stable emulsion was formed which deteriorated only by 10% after one month.
This work was carried out at the Biotechnology Laboratories of the Nuclear Institute for Agriculture & Biology (NIAB), Faisalabad. 相似文献
Dégradation de différents hydrocarbures et production de biosurfactants parPseudomonas aeruginosa isolé d'eaux côtières
Résumé Une bactérie, isolée d'un échantillon d'hydrocarbures épandus, et identifiée commePseudomonas aeruginosa, dégrade l'hexaet l'heptadécane à raison respective de 47 et de 58% du carbone total avec 9 et 12% des substrats respectifs libérés sous la forme de CO2. Avec l'octa- et le nonadécane comme substrats, la biodégradation atteint respectivement 73 et 60% avec 27 et 25% du carbone total transformé en CO2. On a étudié la production de biosurfactant par cette bactérie en utilisant l'hexadécane à 5% (v/v) comme substrat. La tension superficielle de la liqueur mixte, comme celle de son surnageant atteint 30 mN/m par comparaison à 71 mN/m pour l'eau. Lorsque le surnageant est mélangé à l'hexadécane (15, v/v), on forme une émulsion stable qui ne se détériore que de 10% au bout d'un mois.
This work was carried out at the Biotechnology Laboratories of the Nuclear Institute for Agriculture & Biology (NIAB), Faisalabad. 相似文献
1000.
Khalid F. AlHabib Kadhim Sulaiman Jassim Al Suwaidi Wael Almahmeed Alawi A. Alsheikh-Ali Haitham Amin Mohammed Al Jarallah Hussam F. Alfaleh Prashanth Panduranga Ahmad Hersi Tarek Kashour Zohair Al Aseri Anhar Ullah Hani B. Altaradi Kazi Nur Asfina Robert C. Welsh Salim Yusuf 《PloS one》2016,11(1)