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81.
The human motilin gene has been isolated and characterized. The gene spans about 9 kilobase pairs (kb) and the 0.7 kb motilin mRNA is encoded by five exons. The 22-amino-acid motilin sequence is encoded by exons 2 and 3. The human motilin gene was mapped to the p21.2----p21.3 region of chromosome 6 by hybridization of the cloned cDNA to DNAs from a panel of reduced human-mouse somatic cell hybrids and by in situ hybridization to human prometaphase chromosomes. RNA blotting using RNA prepared from various regions of the human gastrointestinal tract revealed high levels of motilin mRNA in duodenum and lower levels in the antrum of the stomach; motilin mRNA could not be detected by this procedure in the esophagus, cardia of the stomach, descending colon or gallbladder.  相似文献   
82.
Nakagawa T  Yano K  Hosokawa K 《Plastic and reconstructive surgery》2003,111(1):141-7; discussion 148-9
If a patient's nipple-areola complex is available for grafting after mastectomy, it is the best material to use for nipple-areola reconstruction. The authors performed delayed autologous nipple-areola complex transfer to reconstructed breasts in 10 patients (mean age, 47 years; range, 40 to 53 years). The nipple-areola complex was cryopreserved with a programmed freezer after mastectomy. Histological examination of the tissue surrounding the nipple and areola eliminated the possibility of cancer invasion. At the time of transfer, the cryopreserved nipple-areola complex was thawed in 37 degrees C water and grafted on a projection made by a denuded dermal flap on the reconstructed breast. Each patient underwent immediate breast reconstruction using an innervated pedicled transverse rectus abdominis musculocutaneous (TRAM) flap. The patients' postoperative courses were uneventful. The timing of transfer ranged from 3 months to 1 year (mean, 5.8 months) after breast reconstruction. Nipple projection was made by the "four" dermal flap in five cases, a round dermal flap in three cases, a double dermal flap in one case, and a denuded skate flap in one case. The follow-up period ranged from 5 to 36 months (mean, 21.8 months). All grafts were adapted. The final evaluation of nipple-areola complex adaptation was good in four cases, fair in four cases, and poor in two cases. Histological examination of the hematoxylin and eosin stains showed no remarkable destruction of the skin of the nipple and areola, and electron microscopic examination of the areola skin revealed no significant change. However, electron microscopic examination of the nipple skin showed serious damage to skin components, including elongation of the desmosome, widening of the intercellular space at the prickle cell and basal layers, and shrinking of prickle and basal cells. Although further development of the freezing process and cryopreservation technique is needed to prevent depigmentation of the nipple and areola, cryopreserved nipple-areola complex transfer to a reconstructed breast could be an alternative method of nipple-areola reconstruction.  相似文献   
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84.
In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted to 2,5-dichloro-2,5-cyclohexadiene-1,4-diol (2,5-DDOL), which is then metabolized to 2,5-dichlorohydroquinone. Here, we isolated from the genomic library of UT26 two genes which expressed 2,5-DDOL dehydrogenase activity when they were transformed into P. putida and Escherichia coli. Both gene products had an apparent molecular size of 28 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The first gene, named linC, located separately from the two genes (linA and linB) which we had already cloned as genes involved in the gamma-HCH degradation. The other, named linX, located about 1 kb upstream of the linA gene encoding gamma-HCH dehydrochlorinase. A gamma-HCH degradation-negative mutant, named UT72, which lacked the whole linC gene but had the intact linX gene was isolated. The linC gene given in a plasmid could complement UT72. These results strongly suggest that the linC gene but not the linX gene is essential for the assimilation of gamma-HCH in UT26. Deduced amino acid sequences of LinC and LinX show homology to those of members of the short-chain alcohol dehydrogenase family.  相似文献   
85.
86.
Angiopoietin-3, a novel member of the angiopoietin family   总被引:11,自引:0,他引:11  
Nishimura M  Miki T  Yashima R  Yokoi N  Yano H  Sato Y  Seino S 《FEBS letters》1999,448(2-3):254-256
A cDNA clone encoding angiopoietin-3 protein (Ang3), a novel member of the angiopoietin family, was identified. Ang3 cDNA was cloned from a human aorta cDNA library. Ang3 is a 503 amino acid protein having 45.1% and 44.7% identity with human angiopoietin-1 and human angiopoietin-2, respectively. Ang3 mRNA is expressed in lung and cultured human umbilical vein endothelial cells (HUVECs). Ang3 mRNA expression in HUVECs was slightly decreased by vascular endothelial cell growth factor treatment, suggesting that the regulation of Ang3 mRNA expression is different from that of Ang2.  相似文献   
87.
Alpha-ketol linolenic acid [KODA, 9,10-ketol-octadecadienoic acid, that is 9-hydroxy-10-oxo-12(Z),15(Z)-octadecadienoic acid] is a signal compound found in Lemna paucicostata after exposure to stress, such as drought, heat or osmotic stress. KODA reacts with catecholamines to generate products that strongly induce flowering, although KODA itself is inactive [Yokoyama et al. (2000) Plant Cell Physiol. 41: 110; Yamaguchi et al. (2001) Plant Cell Physiol. 42: 1201]. We examined the role of KODA in the flower-induction process of Pharbitis nil (violet). KODA was identified for the first time in seedlings of P. nil grown under a flower-inductive condition (16-h dark exposure), by means of LC-SIM and LC-MS/MS. In addition, the changes in endogenous KODA levels (evaluated after esterification of KODA with 9-anthryldiazomethane) during the flower-inductive phase in short day-induced cotyledons were closely related to flower induction. The KODA concentration sharply increased in seedlings during the last 2 h of a 16-h dark period, while the KODA level showed no significant elevation under continuous light. The increase of KODA level occurred in cotyledonal blades, but not in other parts (petiole, hypocotyls and shoot tip). When the 16-h dark period was interrupted with a 10-min light exposure at the 8th h, flower induction was blocked and KODA level also failed to increase. The degree of elevation of KODA concentration in response to 16-h dark exposure was the highest when the cotyledons had just unfolded, and gradually decreased in seedlings grown under continuous light for longer periods, reaching the basal level at the 3rd day after unfolding. Flower-inducing ability also decreased in a similar manner. These results suggest that KODA may be involved in flower induction in P. nil.  相似文献   
88.
89.
Sugar-pendant [60] fullerene derivatives have been prepared from carbohydrate-linked azides 1a-e. Both monosugar (4a-e) and bissugar derivatives (5a-e) produce singlet oxygen ((1)O(2)) under laser irradiation (355 nm) proved by the direct observation of (1)O(2) emission at 1270 nm. Monosugar derivatives exhibit photocytotoxicity varying by the attached sugar molecule.  相似文献   
90.
Burkholderia sp. strain AK-5 utilized 4-aminophenol as the sole carbon, nitrogen, and energy source. A pathway for the metabolism of 4-aminophenol in strain AK-5 was proposed based on the identification of three key metabolites by gas chromatography-mass spectrometry analysis. Strain AK-5 converted 4-aminophenol to 1,2,4-trihydroxybenzene via 1,4-benzenediol. 1,2,4-Trihydroxybenzene 1,2-dioxygenase cleaved the benzene ring of 1,2,4-trihydroxybenzene to form maleylacetic acid. The enzyme showed a high dioxygenase activity only for 1,2,4-trihydroxybenzene, with K(m) and V(max) values of 9.6 micro M and 6.8 micro mol min(-1) mg of protein(-1), respectively.  相似文献   
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