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121.
Štroch Michal Karlický Václav Ilík Petr Ilíková Iva Opatíková Monika Nosek Lukáš Pospíšil Pavel Svrčková Marika Rác Marek Roudnický Pavel Zdráhal Zbyněk Špunda Vladimír Kouřil Roman 《Photosynthesis research》2022,154(1):21-40
Photosynthesis Research - The acclimation of higher plants to different light intensities is associated with a reorganization of the photosynthetic apparatus. These modifications, namely, changes... 相似文献
122.
Gazivoda T Wittine K Lovrić I Makuc D Plavec J Cetina M Mrvos-Sermek D Suman L Kralj M Pavelić K Mintas M Raić-Malić S 《Carbohydrate research》2006,341(4):433-442
The 5,6-di-O-tosylated derivative of l-ascorbic acid was synthesized by selective protection and deprotection of 2,3- and 5,6-dihydroxy functional groups involving 5,6-ditosylation in the final step, while the novel 6-acetoxy, 6-hydroxy, and 6-chloro derivatives of 4,5-didehydro-l-ascorbic acid were obtained by reaction of ditosylated compound with nucleophilic reagents. The analysis of 3JH-4-H-5 homonuclear coupling constants shows that all l-ascorbic acid derivatives except for epoxy and 4,5-didehydro compounds exist in high population as gauche conformers across C-4-C-5 bonds, while 3JC-3-H-5 heteronuclear coupling constants in 4,5-didehydro derivatives indicate cis geometry along C-4-C-5 double bond. The X-ray crystal structure analysis of 2,3-di-O-benzyl-5,6-epoxy- and 5,6-isopropylidene-l-ascorbic acid shows that the oxygen atoms attached at positions 2 and 3 of the lactone ring are disposed in a synperiplanar fashion. Besides that, the dioxolane ring adopts half-chair conformation. The molecules of epoxy derivative are joined into infinite chains by one weak hydrogen bond of C-H...O type. Two O-H...O, and C-H...O hydrogen bonds link the molecules of 5,6-di-O-isopropylidene compound into two-dimensional network. 6-Chloro derivative of 2,3-di-O-benzyl-l-ascorbic acid showed the best cytostatic effects against all tested malignant tumor cells (IC50: approximately 18 microM). 相似文献
123.
Cervenka L Peskova I Foltynova E Pejchalova M Brozkova I Vytrasova J 《Current microbiology》2006,53(5):435-439
Seventeen spice and medicinal plant extracts (methanol and chloroform) were assayed for their antimicrobial activity against
Arcobacter butzleri, A. cryaerophilus, and A. skirrowii. In general, all of the tested extracts were able, to a different extent, to inhibit the growth of the selected Arcobacter species. Cinnamon, bearberry, chamomile, sage and rosemary extracts showed strong antimicrobial activity toward arcobacter
strains tested. Overall, the methanol extracts showed better activity than the chloroform extracts (P < 0.05); however, enhanced antibacterial activity of chloroform extracts of cinnamon and rosemary has been observed in comparison
with their methanol counterparts. The inhibitory dose of the most active extracts (the diameter of zone of inhibition ≥ 20
mm) was determined using the disc-diffusion method as well. 相似文献
124.
Knezović I Dekaris I Gabrić N Cerovski J Barisić A Bosnar D Rastegorac P Parać A 《Collegium antropologicum》2006,30(2):405-408
A clinical trial was undertaken to evaluate the efficacy of hypertonic solution (5% NaCl) in patients who have bullous keratopathy (BK). The aim of the study was to define the stage of the disease and the thickness of cornea in micrometers, which would be the threshold for therapeutic approach. This was a prospective study on 70 eyes of 55 patients. Patients were divided in two groups at the beginning of the study. The first group (n=33 eyes) included patients with initial stage of BK: only stromal component of corneal oedema was present. The second group (n=37 eyes) included patients with advanced stage of BK: the epithelial component of the disease with bullae on the corneal surface had already developed. Visual acuity, central and peripheral thickness of cornea and morphology of the disease was recorded before therapy, 7 days and 4 weeks after administration of hypertonic solution. Our results shown that the efficacy of hypertonic solution correlates with the severity of clinical picture in patients with BK. When 5% NaCl hypertonic solution was applied in the early stage of the disease, when only stromal component of corneal oedema was presented, visual acuity and pachymetry readings were significantly improved. The threshold pachymerty measurement of corneal thickness justifying the application of hypertonic solution was 613-694 microm (in the central corneal area), and 633-728 microm (at corneal periphery). It seems reasonable to apply hypertonic solution to the patients who have BK and whose pachymetric values are below mentioned range. In terminal stages of BK, when superficial bullae (epithelial component) had already developed, treatment with NaCl was not effective and patients had to be submitted to penetrating keratoplasty. 相似文献
125.
Inmaculada Farran Iva McCarthy-Suárez Francisco Río-Manterola Cristina Mansilla Juan José Lasarte Ángel M. Mingo-Castel 《Planta》2010,231(4):977-990
We previously showed that recombinant extra domain A from fibronectin (EDA) purified from Escherichia coli was able to bind to toll-like receptor 4 (TLR4) and stimulate production of proinflammatory cytokines by dendritic cells.
Because EDA could be used as an adjuvant for vaccine development, we aimed to express it from the tobacco plastome, a promising
strategy in molecular farming. To optimize the amount of recombinant EDA (rEDA) in tobacco leaves, different downstream sequences
were evaluated as potential fusion tags. Plants generated by tobacco plastid transformation accumulated rEDA at levels up
to 2% of the total cellular protein (equivalent to approximately 0.3 mg/g fresh weight) when translationally fused to the
first 15 amino acids of green fluorescence protein (GFP). The recombinant adjuvant could be purified from tobacco leaves using
a simple procedure, involving ammonium sulfate precipitation and anion exchange chromatography. Purified protein was able
to induce production of tumour necrosis factor-α (TNF-α) either by bone marrow-derived dendritic cells or THP-1 monocytes.
The rEDA produced in tobacco leaves was also able to induce upregulation of CD54 and CD86 maturation markers on dendritic
cells, suggesting that the rEDA retains the proinflammatory properties of the EDA produced in E. coli and thus could be used as an adjuvant in vaccination against infectious agents and cancer. Taken together, these results
demonstrate that chloroplasts are an attractive production vehicle for the expression of this protein vaccine adjuvant. 相似文献
126.
Inflammatory myofibroblastic tumor (IMT) is a pseudosarcomatous lesion occurring in soft tissue and organs. It is known under a wide number of terms, such as inflammatory pseudotumor, plasma cell granuloma, pseudosarcomatous myofibroblastic proliferation. IMT is most commonly located in the lung, while laryngeal location is rarely described. Due to its biology it can be misdiagnosed as a malignant tumor. We present a case of IMT of larynx, recognized in time and treated with laser ablation. Our case demonstrates the importance of timely IMT recognition in order to avoid overtreatment. This diagnosis should also alert clinicians to close follow-up of these patients. 相似文献
127.
Marinović M Cicvarić T Juretić I Grzalja N Medved I Ahel J 《Collegium antropologicum》2010,34(Z2):243-245
Because of a possible delayed wound healing, critical colonization and infection of wounds present a problem for surgeons. Colonized and infected wounds are a potential source for cross-infection. Molndal technique of wound dressing has proven to be effective in prevention of infection. Also the wound heal better and faster. In our study we wanted to describe the benefits of the Molndal technique wound dressing after laparoscopic cholecistectomy compared to traditional wound dressing technique. Molndal technique consisted of wound dressing with Aquacel Ag--Hydrofiber (ConvaTec, Dublin, Ireland). Traditional technique was performed using gauze compresses and hypoallergic adhesives. We analyzed the results of 100 patients after laparoscopic cholecystectomy. 50 patients were treated by Molndal technique and 50 patients by the traditional technique of wound dressing. In the group treated by Molndal technique only 1 (2%) patient has revealed a wound infection, proven by positive microbiological examination and suppuration, mostly in the subumbilical incision. In the traditional technique group 7 (14%) patients developed wound infection also predominantly in the subumbilical incision. The difference was statistically significant (p < 0.01). Our results are clearly showing that Molndal technique is effective in preventing the infection of subumbilical incision wound and is to by recommend for regular use at designated site after laparoscopic cholecistectomy. 相似文献
128.
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130.
Jana Jersáková Sílvia Castro Nicole Sonk Kathrin Milchreit Iva Schödelbauerová Till Tolasch Stefan Dötterl 《Evolutionary ecology》2010,24(5):1199-1218
Polyploidy has played a key role in plant evolution and diversification. Despite this, the processes governing reproductive
isolation among cytotypes growing in mixed-ploidy populations are still largely unknown. Theoretically, coexistence of diploid
and polyploid individuals in sympatric populations is unlikely unless cytotypes are prezygotically isolated through assortative
pollination. Here, we investigated the pre-mating barriers involved in the maintenance of three co-occurring cytotypes from
the genus Gymnadenia (Orchidaceae): tetraploid and octoploid G. conopsea and tetraploid G. densiflora. We assessed differences in flowering phenology, floral morphology, and visual and olfactory cues, which could lead to assortative
mating. Gas chromatography coupled with electroantennographic detection was used to identify scent compounds with physiological
activity in the two main pollinators, Deilephila porcellus and Autographa gamma. The importance of olfactory cues was also assessed in the field by analysing the moths’ responses to the olfactory display
of the plants, and by following the pollinator’s behaviour on artificial arrays. Our complex approach demonstrated that the
coexistence of Gymnadenia cytotypes in mixed-ploidy populations was only partly explained by differences in floral phenology, as cytotypes with overlapping
flowering (i.e., octoploid G. conopsea and tetraploid G. densiflora) might freely exchange pollen due to only 1 mm differences in spur lengths and the lack of assortative behaviour of pollinators.
While floral colour among the cytotypes was similar, floral scent differed significantly. Though both pollinator species seemed
to physiologically detect these differences, and the floral scent alone was sufficient to attract them, pollinators did not
use this cue to discriminate the cytotypes in the field. The absence of pre-mating barriers among cytotypes, except partial
temporal segregation, suggests the existence of other mechanisms involved in the cytotypes’ coexistence. The genetic differences
in ITS sequences among cytotypes were used to discuss the cytotype’s origin. 相似文献