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121.
A capsule containing an aromatase inhibitor (4-androsten-4-ol-3,17-dione) was subcutaneously implanted in four oligozoospermic beagle dogs and one azoospermic beagle dog with high plasma estradiol-17beta (E2) concentrations (15-19 pg/ml) and low plasma testosterone (T) concentrations (0.6-0.8 ng/ml) for 8 weeks and the effect of the aromatase inhibitor on spermatogenic dysfunction was assessed. Plasma E2 and T concentrations and semen quality were examined at 1 week intervals from 3 weeks before to 12 weeks after the start of treatment. Testicular biopsies were done twice (capsule implantation and removal). Plasma E2 concentrations of all dogs decreased (9-14 pg/ml) and plasma T concentrations increased (2.0-2.6 ng/ml) from 3 weeks after capsule implantation to capsule removal. The mean number of spermatozoa ejaculated by all four oligozoospermic dogs between 4 and 9 weeks after implantation was higher (127 x 10(6) to 205 x 10(6)) than before implantation (20 x 10(6) to 38 x 10(6)) (P < 0.05 and 0.01). Very low numbers (2 x 10(4) to 4 x 10(4)) of immotile spermatozoa were observed between 7 and 8 weeks after implantation in the semen collected from the dog with azoospermia. Before implantation, a few spermatozoa were seen in only one-fifth of the seminiferous tubules in this dog; 8 weeks after implantation, the mean diameter and mean number of round spermatids in the seminiferous tubules in all five dogs were higher than before implantation (P < 0.05). Implantation of the capsule containing the aromatase inhibitor in infertile dogs with abnormally high plasma E2 concentrations improved their spermatogenic function, concurrent with decreased plasma E2 and increased plasma T. 相似文献
122.
Morita N Iizuka K Okita K Oikawa T Yonezawa K Nagai T Tokumitsu Y Murakami T Kitabatake A Kawaguchi H 《American journal of physiology. Endocrinology and metabolism》2004,287(6):E1064-E1069
Contraction of skeletal muscle generates pressure stimuli to intramuscular tissues. However, the effects of pressure stimuli, other than those created by electricity or nerve impulse, on physiological and biochemical responses in skeletal muscles are unknown. The purpose of this study is to examine the effects of a pure pressure stimulus on metabolic responses in a skeletal muscle cell line. Atmospheric pressure was applied to L6 myoblasts using an original apparatus. Succinate dehydrogenase (SDH) activity was evaluated by colorimetric assay using tetrazolium monosodium salt. The amounts of 2-deoxy-[(3)H]glucose uptake and lactate release were measured. SDH activity was 2.6- to 2.9-fold higher in pressurized L6 cells than in nonpressurized L6 cells (P < 0.01), and 2-deoxy-[(3)H]glucose uptake was 2.2-fold higher (P < 0.001). In addition, the amount of released lactate decreased from 6.8 to 3.7 mumol/dish when pressure was applied (P < 0.001). In contrast, the intracellular lactate contents of the pressurized cells were higher than those of nonpressurized cells (P < 0.01). However, the total amount of released lactate and intracellular lactate was lower in the pressurized cells than in nonpressurized cells. These findings demonstrate that a pure pressure stimulus enhances aerobic metabolism in L6 skeletal muscle cells and raise the possibility that elevated intramuscular pressure during muscle activity may be an important factor in stimulating oxidative metabolic responses in skeletal muscles. 相似文献
123.
Satow T Ikeda A Yamamoto J Begum T Thuy DH Matsuhashi M Mima T Nagamine T Baba K Mihara T Inoue Y Miyamoto S Hashimoto N Shibasaki H 《American journal of physiology. Gastrointestinal and liver physiology》2004,287(2):G459-G470
We investigated the role of the cerebral cortex, particularly the face/tongue area of the primary sensorimotor (SMI) cortex (face/tongue) and supplementary motor area (SMA), in volitional swallowing by recording movement-related cortical potentials (MRCPs). MRCPs with swallowing and tongue protrusion were recorded from scalp electrodes in eight normal right-handed subjects and from implanted subdural electrodes in six epilepsy patients. The experiment by scalp EEG in normal subjects revealed that premovement Bereitschaftspotentials (BP) activity for swallowing was largest at the vertex and lateralized to either hemisphere in the central area. The experiment by epicortical EEG in patients confirmed that face/tongue SMI and SMA were commonly involved in swallowing and tongue protrusion with overlapping distribution and interindividual variability. BP amplitude showed no difference between swallowing and tongue movements, either at face/tongue SMI or at SMA, whereas postmovement potential (PMP) was significantly larger in tongue protrusion than in swallowing only at face/tongue SMI. BP occurred earlier in swallowing than in tongue protrusion. Comparison between face/tongue SMI and SMA did not show any difference with regard to BP and PMP amplitude or BP onset time in either task. The preparatory role of the cerebral cortex in swallowing was similar to that in tongue movement, except for earlier activation in swallowing. Postmovement processing of swallowing was lesser than that of tongue movement in face/tongue SMI; probably suggesting that the cerebral cortex does not play a significant role in postmovement processing of swallowing. SMA plays a supplementary role to face/tongue SMI both in swallowing and tongue movements. 相似文献
124.
Tanitame A Oyamada Y Ofuji K Kyoya Y Suzuki K Ito H Kawasaki M Nagai K Wachi M Yamagishi J 《Bioorganic & medicinal chemistry letters》2004,14(11):2857-2862
In this study, we report the design, synthesis and structure-activity relationships of novel indazole derivatives as DNA gyrase inhibitors with Gram-positive antibacterial activity. Our results show that selected compounds from this series exhibit potent antibacterial activity against Gram-positive bacteria including multi-drug resistant strains that is methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE). 相似文献
125.
Current cell-free protein expression systems are capable of synthesizing proteins with high speed and accuracy; however, the yields are low due to their instability over time. Escherichia coli based systems are not always sufficient for expression of eukaryotic proteins. This report reviews a high-throughput protein production method based on the cell-free system prepared from eukaryote, wheat embryos. We first demonstrate a method for preparation of this extract that exhibited a high degree of stability and activity. To maximize translation yield and throughput, we address and resolve the following issues: (1) optimization of the ORF flanking regions; (2) PCR-based generation of DNA for mRNA production; (3) expression vectors for large-scale protein production; and (4) a translation reaction that does not require a membrane. The combination of these elemental processes with robotic automation resulted in high-throughput protein synthesis. 相似文献
126.
Kon T Tanigawa T Hayamizu K Shen M Tsuji T Naito Y Yoshikawa T 《Redox report : communications in free radical research》2004,9(6):325-330
Singlet oxygen is regarded as contributing to the pathogenesis of various diseases including light-induced skin disorders and inflammatory response. In this study, the correlation between singlet oxygen quenching activity (SOQA) of human serum and blood biochemistry or life-style was evaluated. Healthy volunteers were recruited and carried out a measurement of SOQA by using electron paramagnetic resonance (EPR) and a questionnaire survey about a smoking. It was demonstrated that major quenchers of singlet oxygen in serum are proteins, and small molecular anti-oxidants relatively play a minor role. SOQA of whole sera showed no correlation with protein concentration, but positively correlated with SOQA of small molecular fraction. In vitro studies demonstrated that the decrease of sulfhydryl groups by NO or superoxide significantly attenuated SOQA of albumin. Together, these results may imply that the underlying oxidative condition in each individual influences both small molecular antioxidant states and the sulfhydryl content of serum proteins. SOQA of sera from women with a smoking history was significantly lower compared to non-smoking women, suggesting that the smoking habit impaired the defense mechanism against singlet oxygen. 相似文献
127.
Aoki KF Ueda N Yamaguchi A Kanehisa M Akutsu T Mamitsuka H 《Bioinformatics (Oxford, England)》2004,20(Z1):i6-14
MOTIVATION: The study of carbohydrate sugar chains, or glycans, has been one of slow progress mainly due to the difficulty in establishing standard methods for analyzing their structures and biosynthesis. Glycans are generally tree structures that are more complex than linear DNA or protein sequences, and evidence shows that patterns in glycans may be present that spread across siblings and into further regions that are not limited by the edges in the actual tree structure itself. Current models were not able to capture such patterns. RESULTS: We have applied a new probabilistic model, called probabilistic sibling-dependent tree Markov model (PSTMM), which is able to inherently capture such complex patterns of glycans. Not only is the ability to capture such patterns important in itself, but this also implies that PSTMM is capable of performing multiple tree structure alignments efficiently. We prove through experimentation on actual glycan data that this new model is extremely useful for gaining insight into the hidden, complex patterns of glycans, which are so crucial for the development and functioning of higher level organisms. Furthermore, we also show that this model can be additionally utilized as an innovative approach to multiple tree alignment, which has not been applied to glycan chains before. This extension on the usage of PSTMM may be a major step forward for not only the structural analysis of glycans, but it may consequently prove useful for discovering clues into their function. 相似文献
128.
Roberto?H?Higa Roberto?C?Togawa Arnaldo?J?Montagner Juliana?CF?Palandrani Igor?KS?Okimoto Paula?R?Kuser Michel?EB?Yamagishi Adauto?L?Mancini Goran?NeshichEmail author 《BMC bioinformatics》2004,5(1):107
Background
The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user. 相似文献129.
Ohhata T Tachibana M Tada M Tada T Sasaki H Shinkai Y Sado T 《Genesis (New York, N.Y. : 2000)》2004,40(3):151-156
One of the two X chromosomes becomes inactivated during early development of female mammals. Recent studies demonstrate that the inactive X chromosome is rich in histone H3 methylated at Lys-9 and Lys-27, suggesting an important role for these modifications in X-inactivation. It has been shown that in the mouse Eed is required for maintenance of X-inactivation in the extraembryonic lineages. Interestingly, Eed associates with Ezh2 to form a complex possessing histone methyltransferase activity predominantly for H3 Lys-27. We previously showed that G9a is one of the histone methyltransferases specific for H3 Lys-9 and is essential for embryonic development. Here we examined X-inactivation in mouse embryos deficient for G9a. Expression of Xist, which is crucial for the initiation of X-inactivation, was properly regulated and the inactivated X chromosome was stably maintained even in the absence of G9a. These results demonstrate that G9a is not essential for X-inactivation. 相似文献
130.
Osakabe N Yamagishi M Natsume M Yasuda A Osawa T 《Experimental biology and medicine (Maywood, N.J.)》2004,229(1):33-39
Proanthocyanidins derived from cacao (CLP) have various antipathophysiological functions. We have tested whether dietary supplementation with CLP prevents cataract formation in rats with diabetes induced by streptozotocin (STZ), using histological, histochemical, and biochemical analyses. Starting at 7 days after the streptozotocin challenge, the animals were fed either a normal diet or a diet containing 0.5% w/w CLP over 10 weeks. There were no significant differences in plasma and urine glucose concentrations, plasma fructose amines, and plasma thiobarbituric reactive substances (TBARS) between the two dietary groups. Antioxidant status as assessed by measuring lipid peroxide production in plasma in response to azocompounds was lower in the STZ-rats fed control diet than in animals fed CLP. Opacity was first detected in the lenses of the control dietary group 5 weeks after STZ injection and cataracts had developed in the majority of these animals by 10 weeks. These changes were rarely seen in the STZ/CLP diet group. Histological examinations of the eyes of the STZ-treated normal diet group revealed focal hyperplasia of the lens epithelium and liquefaction of cortical fibers. There were similar but considerably less severe changes in the animals fed CLP. Hydroxynonenal (HNE), a marker of oxidative stress, was detected immunohistochemically in the lenses of the STZ-treated normal diet group, but not of those receiving CLP. Our findings suggest that CLP inhibits diabetes-induced cataract formation possibly by virtue of its antioxidative activity. 相似文献