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991.
Stabilizing the Efficiency Beyond 20% with a Mixed Cation Perovskite Solar Cell Fabricated in Ambient Air under Controlled Humidity
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Perovskite solar cells have evolved to have compatible high efficiency and stability by employing mixed cation/halide type perovskite crystals as pinhole‐free large grain absorbers. The cesium (Cs)–formamidium–methylammonium triple cation‐based perovskite device fabricated in a glove box enables reproducible high‐voltage performance. This study explores the method to reproduce stable and high power conversion efficiency (PCE) of a triple cation perovskite prepared using a one‐step solution deposition and low‐temperature annealing fully conducted in controlled ambient humidity conditions. Optimizing the perovskite grain size by Cs concentration and solution processes, a route is created to obtain highly uniform, pinhole‐free large grain perovskite films that work with reproducible PCE up to 20.8% and high preservation stability without cell encapsulation for more than 18 weeks. This study further investigates the light intensity characteristics of open‐circuit voltage (Voc) of small (5 × 5 mm2, PCE > 20%) and large (10 × 10 mm2, PCE of 18%) devices. Intensity dependence of Voc shows an ideality factor in the range of 1.7‐1.9 for both devices, implying that the triple cation perovskite involves trap‐assisted recombination loss at the hetero junction interfaces that influences Voc. Despite relatively high ideality factor, perovskite device is capable of supplying high power conversion efficiency under low light intensity (0.01 Sun) whereas maintaining Voc over 0.9 V. 相似文献
992.
Setsuko Tohno Yoshiyuki Tohno Takeshi Minami Yuko Okazaki Masako Utsumi Fumio Nishiwaki Yumi Moriwake Takashi Naganuma Masa-oki Yamada Tsutomu Araki 《Biological trace element research》1997,57(1):27-37
The relative contents (RCs) of elements in the femoral arteries as well as the thoracic aorta, coronary, basilar, and radial
arteries from 26 subjects within the age range between 55 and 92 yr old, were analyzed by inductively coupled plasma atomic
emission spectrometry.
The RCs of calcium and phosphorus in the femoral arteries started to increase before the age of 60 yr. The RCs of magnesium
increased after the age of 70 yr. However, the RCs of sulfur did not change significantly within the age range between 55
and 92 yr.
With regard to localization of the mineral accumulations in the femoral arterial wall, it was found that the accumulations
of calcium and phosphorus occurred only in the tunica media, only in the tunica intima, or in both the tunica media and the
tunica intima. The manner of accumulation of calcium and phosphorus in the femoral arterial wall was different from that in
the aortic wall.
The average RCs of calcium in the 26 specimens were the highest in the femoral artery, followed in descending order by the
thoracic aorta, coronary, basilar, and radial arteries. The average RCs of phosphorus were highest in the thoracic aorta,
followed by the coronary, femoral, basilar, and radial arteries. It is noted that the accumulation of mineral elements never
occurred uniformly in all the arteries. 相似文献
993.
Yoshiyuki Tohno Setsuko Tohno Masako Utsumi Takeshi Minami Masayo Ichii Yuko Okazaki Fumio Nishiwaki Yumi Moriwake Takashi Naganuma Masa-oki Yamada Tsutomu Araki 《Biological trace element research》1997,59(1-3):167-175
To elucidate age-related changes of mineral contents in human bones, element contents of human vertebrae and auditory ossicles
were determined by inductively coupled plasma atomic-emission spectrometry. The cervical, thoracic, and lumbar vertebrae were
removed from 12 vertebral columns. The mallei of auditory ossicle were removed from 27 cadavers.
It was found that average relative contents (RCs) of calcium and phosphorus in cervical, thoracic, and lumbar vertebrae remained
almost constant within ages ranging from 46 to 99 y. In addition, it was found that the RCs of calcium and phosphorus in men’s
and women’s mallei remained constant within ages ranging from 40 to 98 yr. These results support the view that there is no
significant agedependent change of mineral contents in human bones. 相似文献
994.
Hideyuki Nagao Toshimasa Shiraishi Satoko Oshima Masanori Koike Tsutomu Iijima 《Mycoscience》1997,38(4):379-385
Verticillium dahliae race-2 can invade the resistant cultivars of tomato possessing theVe gene. This new race was recently found in several regions in Japan, and 10 isolates ofV. dahliae race-2 from these regions were used in our study. Pathogenicity tests identified these isolates as the tomato pathotype (B).
We examined the vegetative compatibility of 8 of these 10 Japanese isolates ofV. dahliae race-2 to estimate their genetic relatedness with the testers of Japanese vegetative compatibility group previously proposed
(VCGJ) usingnit mutants. Compatiblenit1 and NitM mutants were obtained from allV. dahliae race-2 isolates. Selected representativenit1 and NitM mutants of eachV. dahliae race-2 isolates were paired with VCGJ testers. All isolates ofV. dahliae race-2 showed a strong reaction with VCGJ2, i.e., tomato pathotype. All isolates ofV. dahliae race-2 except for isolate To22 reacted weakly to VCGJ1 and J3. Japanese isolates ofV. dahliae race-2 were assigned as VCGJ2 and were hence vegetatively closely related with those ofV. dahliae race-1. The origin of Japanese isolates ofV. dahliae race-2 was discussed. 相似文献
995.
Grossmann Gertie; Suzuki Yasuhiro; Robertson Bengt; Kobayashi Tsutomu; Berggren Per; Li Wen-Zhi; Song Guo-Wei; Sun Bo 《Journal of applied physiology》1997,82(6):2003-2010
Grossmann, Gertie, Yasuhiro Suzuki, Bengt Robertson, TsutomuKobayashi, Per Berggren, Wen-Zhi Li, Guo-Wei Song, and Bo Sun.Pathophysiology of neonatal lung injury induced by monoclonal antibody to surfactant protein B. J. Appl.Physiol. 82(6): 2003-2010, 1997.Near-termnewborn rabbits were exposed via the airways to a monoclonal antibodyto surfactant protein B and ventilated for 0-120 min. Controlanimals received nonspecific rabbit or mouse immunoglobulin G, saline,or no material via the airways. Administration of the antibody at 40mg/kg elicited an immediate, significant fall in lung-thorax complianceassociated with progressive intra-alveolar edema and/oralveolar collapse and necrosis and desquamation of airway epithelium,and hyaline membranes. The vascular-to-alveolar leak of human albuminand human immunoglobulin G, injected intravenously at birth anddetermined in lung lavage fluid 60-120 min after instillation ofthe antibody, was 1.8% for the left lung, with no difference betweenthe markers. The average leak in control animals ventilated for 120 minwas <0.3% (P < 0.05). Cytospin preparations of lung lavage fluid from animals exposed to the antibodyshowed significantly increased recruitment of neutrophilic granulocytes. The pathology and pathophysiology of neonatal lung injuryinduced by the monoclonal antibody to surfactant protein B probablyreflect a combination of direct inactivation of surfactant and aninflammatory response triggered by the immune reaction. 相似文献
996.
Goto Masahiro Ono Tsutomu Nakashio Fumiyuki Hatton T. Alan 《Biotechnology Techniques》1996,10(3):141-144
Summary The extraction behavior of native and heated-denatured -chymotrypsin has been investigated with two different reversed micellar systems. A large difference in the degree of extraction was observed for the native relative to the denatured -chymotrypsin. In particular, mixed reversed micelles formulated with DOLPA (dioleyl phosphoric acid) and AOT show a high selectivity for the active -chymotrypsin. 相似文献
997.
Hiroshi Ueno Tsutomu Hohdatsu Yasukazu Muramatsu Hiroyuki Koyama Chiharu Morita 《Microbiology and immunology》1996,40(9):617-620
It was found that Bartonella henselae (B. henselae) may induce clinical disorders in cats in natural conditions from a comparison of the serological status for B. henselae with the serostatus for feline immunodeficiency virus (FIV) and several clinical characteristics in 170 domestic cats. Seropositivity for B. henselae was not significantly different between FIV antibody-positive and -negative cats (18.4% vs 16.0%). The incidence of clinical characteristics were compared among four cat groups distinguished by the reactivity of sera against B. henselae and FIV. The incidence of lymph node swelling was lower in only FIV antibody-positive cats (3.0%), but higher in B. henselae antibody-positive cats (13.6%) and significantly higher in both B. henselae and FIV antibody-positive cats (42.9%) compared with the incidence of lymph node swelling in cats which were negative for both antibodies (5.5%). The same relation was also observed for the incidence of gingivitis among the 4 cat groups, suggesting that coinfection of B. henselae and FIV may be associated with gingivitis and lymphadenopathy in cats. 相似文献
998.
S. Kobayashi Tsutomu Iwata Makiko Saito R. Iwasaki Hiroshi Matsumoto Shinichi Naritaka Yoichi Kono Yasuhide Hayashi 《Human genetics》1996,97(4):424-430
Alterations of the Bruton's tyrosine kinase(Btk) gene are responsible for X-linked agammaglobulinemia (XLA). Although mutations in various regions were reported mainly in the Caucasian population, correlation between the locations of mutation and the clinical phenotypes remains unclear. We report 12 abnormalities of theBtk gene found in 12 unrelated families out of 14 XLA families in Japan and their clinical features. We utilized Southern blotting and single-strand conformation polymorphism (SSCP) analysis. Gene rearrangement in the kinase domain was identified in two patients by Southern blotting. Seven point mutations, two small deletions, and one small insertion were detected by SSCP and sequencing. The SSCP analysis also provided information about the carriers in these families. We found some clinical heterogeneity in the affected family members with the same gene mutation. Moreover, there is considerable inconsistency between the locations of gene aberrations and the immunological phenotypes. Some patients with a nonsense mutation, which may result in the lack of kinase domain, have detectable B cells and immunoglobulins. These identified alterations will provide valuable clues to theBtk protein function and the pathogenesis of XLA. 相似文献
999.
Takashi Tokino Tsutomu Urano Tomohisa Furuhata Mieko Matsushima Takashi Miyatsu Shin Sasaki Yusuke Nakamura 《Human genetics》1996,97(5):625-631
We have isolated human cDNA and genomic clones of a gene termed p57KIP2, which is related to the p21WAF1 and p27KIP1 genes that encode inducible inhibitors of cyclin-dependent kinase activity. The p57 gene contains three GC-rich introns of
166 bp, 566 bp, and 83 bp, and two of the four exons correspond to coding regions. Alternative splicing generates the heterogeneity
in the translational initiations. As this gene has been localized to chromosomal band 11p15.5, a region thought to be the
location of a tumor suppressor gene(s) for carcinomas of the breast, bladder, and liver, we have examined a large number of
tumors for genetic alterations of p57. Although no somatic mutation has been detected, we have found several normal variations
in this gene, including four types of 12-bp in-frame deletions in the proline/alanine repeating domain, in which nearly 40
motifs, viz., 5′-CCGGCC-3′, are tandemly repeated.
Received: 9 August 1995 相似文献
1000.
We investigated the molecular basis for Ca-dependent inactivation of the cardiac L-type Ca channel. Transfection of HEK293 cells with the wild-type α1C or its 3′ deletion mutant (α1C−3′del) produced channels that exhibited prominent Ca-dependent inactivation. To identify structural regions of α1C involved in this process, we analyzed chimeric α1 subunits in which one of the major intracellular domains of α1C was replaced by the corresponding region from the skeletal muscle α1S subunit (which lacks Ca-dependent inactivation). Replacing the NH2 terminus or the III–IV loop of α1C with its counterpart from α1S had no appreciable effect on Ca channel inactivation. In contrast, replacing the I–II loop of α1C with the corresponding region from α1S dramatically slowed the inactivation of Ba currents while preserving Ca-dependent inactivation. A similar but less pronounced result was obtained with a II–III loop chimera. These results suggest that the I–II and II–III loops of α1C may participate in the mechanism of Ca-dependent inactivation. Replacing the final 80% of the COOH terminus of α1C with the corresponding region from α1S completely eliminated Ca-dependent inactivation without affecting inactivation of Ba currents. Significantly, Ca-dependent inactivation was restored to this chimera by deleting a nonconserved, 211–amino acid segment from the end of the COOH terminus. These results suggest that the distal COOH terminus of α1S can block Ca-dependent inactivation, possibly by interacting with other proteins or other regions of the Ca channel. Our findings suggest that structural determinants of Ca-dependent inactivation are distributed among several major cytoplasmic domains of α1C. 相似文献