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31.
D C Birdsell G E Gavelin G M Kemsley K S Hein 《Plastic and reconstructive surgery》1981,68(5):742-745
An experiment was designed to compare the "holding power" or "staying power" of absorbable (polyglycolic acid and polyglactin 910) and nonabsorbable (nylon) suture. The aim of this experiment was to determine what provides the lasting strength of the bond between soft tissues that are approximated or plicated. When correcting the rectus diastasis during abdominoplasty, we used nylon sutures in 15 patients and absorbable synthetic sutures in 15 other patients. We then marked the closed folds of the rectus sheath with small metal vascular clips. Two days later and approximately 6 months after operation an upright anteroposterior abdominal x-ray was taken and the position of the metal clips was compared in the test groups. Although there was usually slight separation of the clips after 6 months, no significant difference between the two groups was noted, thereby indicating that holding power is not related to type of suture material but more likely to fibroplasia. 相似文献
32.
Estrogen dependent ciliogenesis in the chick oviduct 总被引:1,自引:0,他引:1
Both the hormone dependency and the morphological details of estrogen-dependent ciliogenesis in the shell gland of the chick oviduct were investigated. Ciliogenesis was initiated on day 3 of estrogen treatment, and progressively more cells became differentiated until, on day 10, 55% ciliation occurred with 17-estradiol (1 mg/day) and 75% ciliation occurred with diethylstilbestrol (1 mg/day). Simultaneous administration of progesterone with diethylstilbestrol (1 mg each/day for 10 days) caused a 50% depression in the number of ciliated cells on day 10. The rate of ciliogenesis was found to be affected by progesterone and the type of estrogen administered. The minimum stimulatory dose of estradiol was found to be between 0.01 mg/day and 0.05 mg/day. Ciliogenic cells were first recognized by the appearance of pro-basal bodies in the apical portion of the cell. Pro-basal body maturation and cilium formation were the same as those described for the chick trachea. Ciliogenesis in the chick was found to be homologous to estrogen-dependent ciliogenesis in various mammalian oviducts. 相似文献
33.
H E Hein 《Experimental parasitology》1975,38(3):271-278
Young chickens inoculated with multiple low doses of mixed oocysts of Eimeria acervulina, E. brunetti, and E. maxima had a high level of resistance to reinfection with a mixed challenge dose on Day 28, Day 84, or Day 140. Immunity was enhanced when the number of immunizing doses was increased from three to four. Resistance was also high in birds maintained on a proprietary mixture of amprolium, ethopabate, and sulphaquinoxaline (Pancoxin-Merck, Sharp and Dohme Ltd.) during immunization, although immunity to E. acervulina was lower in these birds. Oocyst production was lower in birds given mixed infections as compared with that of birds given pure infections with similar doses of oocysts. Competition between species did not inhibit the development of immunity in birds given low doses of mixed oocysts. 相似文献
34.
Helen E. Hein 《Experimental parasitology》1976,40(2):250-260
Resistance to reinfection varied with the species of Eimeria and with the number of oocysts in the inoculum. Chickens immunized with doses of 20,000 and 80,000 oocysts of E. acervulina, 312 and 1250 oocysts of E. brunetti or E. necatrix, or 1250 and 5000 oocysts of E. maxima at 2 and 4 weeks of age, respectively, were almost completely immune to a challenge dose at 6 weeks of age. Resistance was slightly less in chickens immunized with 1250 and 5000 oocysts of E. acervulina or 312 and 1250 oocysts of E. maxima. Birds given three immunizing infections of 1250, 5000, and 20,000 oocysts of E. maxima were completely immune 8 weeks after the last dose. Resistance was slightly less in birds immunized with similar doses of E. brunetti or E. necatrix. Doses of 20,000, 80,000, and 320,000 oocysts appeared necessary to confer a high level of immunity to E. acervulina. More than three low doses of oocysts appear necessary to induce a complete and enduring immunity against a high challenge for E. acervulina, E. brunetti, and E. necatrix. Higher immunizing doses would not be satisfactory due to the pathogenic effects of the coccidia after the initial infection. 相似文献
35.
K D Hein M E Wechsler R M Schwartzstein D J Morris 《Plastic and reconstructive surgery》1999,103(6):1706-1708
Adult respiratory distress syndrome occurred in a patient who had received dextran as a routine antithrombotic agent during and after free TRAM breast reconstruction. Although most patients who receive dextran have no adverse reaction, particularly after hapten inhibition by dextran 1 infusion, the serious nature of this complication in an elective operation calls into question the continuing routine use of dextran in microsurgery. 相似文献
36.
Xiao Lin Tianqiao Song Sebastian Fairhead Kamil Witek Agathe Jouet Florian Jupe Agnieszka I. Witek Hari S. Karki Vivianne G. A. A. Vleeshouwers Ingo Hein Jonathan D. G. Jones 《Molecular Plant Pathology》2020,21(11):1502-1512
Potato late blight, caused by the oomycete pathogen Phytophthora infestans, significantly hampers potato production. Recently, a new Resistance to Phytophthora infestans (Rpi) gene, Rpi-amr1, was cloned from a wild Solanum species, Solanum americanum. Identification of the corresponding recognized effector (Avirulence or Avr) genes from P. infestans is key to elucidating their naturally occurring sequence variation, which in turn informs the potential durability of the cognate late blight resistance. To identify the P. infestans effector recognized by Rpi-amr1, we screened available RXLR effector libraries and used long read and cDNA pathogen-enrichment sequencing (PenSeq) on four P. infestans isolates to explore the untested effectors. Using single-molecule real-time sequencing (SMRT) and cDNA PenSeq, we identified 47 highly expressed effectors from P. infestans, including PITG_07569, which triggers a highly specific cell death response when transiently coexpressed with Rpi-amr1 in Nicotiana benthamiana, suggesting that PITG_07569 is Avramr1. Here we demonstrate that long read and cDNA PenSeq enables the identification of full-length RXLR effector families and their expression profile. This study has revealed key insights into the evolution and polymorphism of a complex RXLR effector family that is associated with the recognition by Rpi-amr1. 相似文献
37.
Jamin B. Hein Dimitriya H. Garvanska Isha Nasa Arminja N. Kettenbach Jakob Nilsson 《The Journal of cell biology》2021,220(5)
Tight regulation of the APC/C-Cdc20 ubiquitin ligase that targets cyclin B1 for degradation is important for mitotic fidelity. The spindle assembly checkpoint (SAC) inhibits Cdc20 through the mitotic checkpoint complex (MCC). In addition, phosphorylation of Cdc20 by cyclin B1–Cdk1 independently inhibits APC/C–Cdc20 activation. This creates a conundrum for how Cdc20 is activated before cyclin B1 degradation. Here, we show that the MCC component BubR1 harbors both Cdc20 inhibition and activation activities, allowing for cross-talk between the two Cdc20 inhibition pathways. Specifically, BubR1 acts as a substrate specifier for PP2A-B56 to enable efficient Cdc20 dephosphorylation in the MCC. A mutant Cdc20 mimicking the dephosphorylated state escapes a mitotic checkpoint arrest, arguing that restricting Cdc20 dephosphorylation to the MCC is important. Collectively, our work reveals how Cdc20 can be dephosphorylated in the presence of cyclin B1-Cdk1 activity without causing premature anaphase onset. 相似文献
38.
Lyndon D. Estes Hein Beukes Bethany A. Bradley Stephanie R. Debats Michael Oppenheimer Alex C. Ruane Roland Schulze Mark Tadross 《Global Change Biology》2013,19(12):3762-3774
Crop model‐specific biases are a key uncertainty affecting our understanding of climate change impacts to agriculture. There is increasing research focus on intermodel variation, but comparisons between mechanistic (MMs) and empirical models (EMs) are rare despite both being used widely in this field. We combined MMs and EMs to project future (2055) changes in the potential distribution (suitability) and productivity of maize and spring wheat in South Africa under 18 downscaled climate scenarios (9 models run under 2 emissions scenarios). EMs projected larger yield losses or smaller gains than MMs. The EMs’ median‐projected maize and wheat yield changes were ?3.6% and 6.2%, respectively, compared to 6.5% and 15.2% for the MM. The EM projected a 10% reduction in the potential maize growing area, where the MM projected a 9% gain. Both models showed increases in the potential spring wheat production region (EM = 48%, MM = 20%), but these results were more equivocal because both models (particularly the EM) substantially overestimated the extent of current suitability. The substantial water‐use efficiency gains simulated by the MMs under elevated CO2 accounted for much of the EM?MM difference, but EMs may have more accurately represented crop temperature sensitivities. Our results align with earlier studies showing that EMs may show larger climate change losses than MMs. Crop forecasting efforts should expand to include EM?MM comparisons to provide a fuller picture of crop–climate response uncertainties. 相似文献
39.
Larissa Wakefield Valerie Cornish Hilary Long Akane Kawamura Xiaoyan Zhang David W. Hein 《Biomarkers》2013,18(1):106-118
Arylamine N-acetyltransferase (NAT) genes in humans and in rodents encode polymorphic drug metabolizing enzymes. Human NAT1 (and the murine equivalent mouse Nat2) is found early in embryonic development and is likely to have an endogenous role. We report the detailed expression of the murine gene (Nat2) and encoded protein in mouse embryos, using a transgenic mouse model bearing a lacZ transgene inserted into the coding region of mouse Nat2. In mouse embryos, the transgene was expressed in sensory epithelia, epithelial placodes giving rise to visceral sensory neurons, the developing pituitary gland, sympathetic chain and urogenital ridge. In Nat2+/+ mice, the presence and activity of Nat2 protein was detected in these tissues and their adult counterparts. Altered expression of the human orthologue in breast tumours, in which there is endocrine signalling, suggests that human NAT1 should be considered as a potential biomarker for neuroendocrine tissues and tumours. 相似文献
40.
Esther Hafkamp-de Groen Agnes M. M. Sonnenschein-van der Voort Johan P. Mackenbach Liesbeth Duijts Vincent W. V. Jaddoe Henri?tte A. Moll Albert Hofman Johan C. de Jongste Hein Raat 《PloS one》2013,8(11)