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101.
Minami Y Morishita Y Yamamoto T Iijima T Fukasawa M Ishikawa S Ichimura H Noguchi M 《Acta cytologica》2004,48(2):243-248
BACKGROUND: Pulmonary papillary adenoma is a benign pulmonary neoplasm. Previously pulmonary papillary adenoma was described in terms of immunohistochemistry and ultrastructure. However, there are no previous reports describing the cytologic characteristics of pulmonary papillary adenoma. CASE: A 50-year-old male was admitted for evaluation of a coin lesion in the left upper lung field. Radiologic images showed a solid, round tumor approximately 25 mm in diameter in the left upper lung. Transbronchial needle aspiration biopsy (TBNA) was performed, and small numbers of atypical cells were collected. Adenocarcinoma was suggested clinically, and left upper segmentectomy was performed. The histologic diagnosis was pulmonary papillary adenoma. Imprint cytology of the cut surface of the tumor showed tumor cells arranged in sheets that contained scant or vesicular cytoplasm. The nuclei were oval or round, without obvious anisokaryosis, and their chromatin was fine, without hyperchromasia. Cytologically, the nuclei of the tumor cells in the imprint specimen (38.70 +/- 8.69 microns 2) were uniform in size and similar to the atypical cells in the TBNA specimen (38.29 +/- 11.56 microns 2) but significantly larger than the nuclei of the bronchial cells (23.61 +/- 5.98 microns 2) (P < .0001). CONCLUSION: The cytologic appearance of pulmonary papillary adenoma was characterized morphologically and morphometrically. The possibility of cytodiagnosis by TBNA was suggested. 相似文献
102.
103.
Ono EY Fungaro MH Sofia SH Figueira EL Gerage AC Ichinoe M Sugiura Y Ueno Y Hirooka EY 《Mycopathologia》2004,158(4):451-455
Eleven feed samples associated with six animal (horse and poultry) intoxication outbreaks (1991) in the state of Paraná, Brazil,
were evaluated for fungal and fumonisin contamination. In order to estimate the␣trend of livestock intoxication, fumonisin
contamination was monitored in corn produced both at the commercial level (1991, 1995 crop), and in an experimental field
at a local Agronomy Institute (1997 crop). The total mould count in the feed samples ranged from 2.9 × 103 to 1.9 × 107 CFU/g, with Fusarium verticillioides as the predominant species, at a high count of 2.4 × 104–6.5 × 105 CFU/g. Fumonisins (FB1 + FB2) were detected in all corn-based feed samples at levels ranging from 2.89 to 14.54 μg/g. All 27 Northern corn samples (1991 crop) were contaminated with fumonisins at levels ranging from 2.32 to 16.64 μg/g. Twenty-six (96.3%) out of 27 corn samples from the Central-Southern region (1995 crop) were positive for fumonisins (FB1+FB2), with the range of 0.07–3.66 μg/g, while all 37 Northern samples (1995 crop) were contaminated with fumonisins ranging from 0.57 to 9.97 μg/g. Twenty-one out of 37 corn samples from the Northern region (1997 crop) were positive for fumonisins, but at low level
(range of 0.05–2.67 μg/g). The results showed a decreasing trend in fumonisin contamination over the years. Nowadays animal intoxication outbreaks
rarely occur in this State, as both animal producers and feed industries have become conscious about monitoring of corn and
other raw materials at the quality control level. 相似文献
104.
105.
A 900 bp genomic region from the mouse dystrophin promoter directs lacZ reporter expression only to the right heart of transgenic mice 总被引:1,自引:0,他引:1
Shigemi Kimura Kuniya Abe Misao Suzuki Masakatsu Ogawa Kowashi Yoshioka Tadasi Kaname Teruhisa Miike Ken-ichi Yamamura 《Development, growth & differentiation》1997,39(3):257-265
In order to study the regulatory mechanism of developmental and tissue-specific expression of the muscle type dystrophin gene in mice, transgenic mice were generated carrying the 900 bp genomic fragment derived from the muscle type dystrophin promoter region fused to the bacterial lacZ gene. Six independent transgenic mouse lines showed specific reporter gene expression in the right heart, but not in skeletal or smooth muscle. The reporter gene expression was first detected in the presumptive right ventricle of the embryos at 8.5 days post coitum, and the expression continued only in the right ventricle throughout the development and at the adult stage. The results indicate that the 900 bp genomic fragment contains the regulatory element required for expression of dystrophin only in the right heart, suggesting that distinct elements are responsible for the expression in the left and right compartments of the heart, and/or in skeletal and smooth muscle cells. Based on these findings, the relationship between defects in muscle type promoter and the diseases caused by abnormal dystrophin expression is discussed. 相似文献
106.
Masashi Seto Masakatsu Ida Noriko Okita Takashi Hatta Eiji Masai Masao Fukuda 《Biotechnology letters》1996,18(11):1305-1308
Summary Polychlorinated biphenyl (PCB) transformation activity of a strong PCB degrader, Rhodococcus sp. strain RHA1, was examined in different concentrations of PCBs. A extremely strong PCB transformation activity was observed on 30 g PCB/ml. At 50 and 100 g/ml, transformation activities were diminished. In the case of bphA insertion mutant, RDA1, transformation activity in the presence of ethylbezene was poor even at 30 g/ml. This indicated that the bphA dependent system would play a major role in PCB transformation by RHA1. Greater transformation activity of RHA1 was observed in the presence of ethylbenzene than in the presence of biphenyl. 相似文献
107.
Nobuko Watanabe Kumiko Nagamatsu Toshiyuki Mizuno Masakatsu Matsumoto 《Luminescence》2005,20(2):63-72
Bicyclic dioxetanes bearing 5-(t-butyldimethylsiloxy)inden-2-yl, 3, or 5-(t-butyldimethylsiloxy)benzo(b)thiazol-2-yl, 4, were synthesized. On treatment with large excess of tetrabutylammonium fluoride in DMSO, dioxetane, 3, decomposed rapidly with accompanying emission of red (vermilion) light (lambda(max) (CL) = 637 nm). Comparing the chemiluminescent properties for 3 with those for related dioxetane, 1, in which pi-conjugation system is not fixed in plane, both CIEEL-decay rate and chemiluminescent efficiency were found to be improved for 3. Chemiluminescent decomposition of dioxetane, 4, was similarly induced to emit crimson light (lambda(max) (CL) = 725 nm), though the chemiluminescent efficiency was low. 相似文献
108.
Makoto Koizumi Rika Koga Hitoshi Hotoda Toshinori Ohmine Hidehiko Furukawa Toshinori Agatsuma Takashi Nishigaki Koji Abe Toshiyuki Kosaka Shinya Tsutsumi Junko Sone Masakatsu Kaneko Satoshi Kimura Kaoru Shimada 《Bioorganic & medicinal chemistry》1998,6(12):2469-2475
We have found that a hexadeoxyribonucleotide (5′TGGGAG3′, R-95288), Koizumi, M. et al. Bioorganic & Medicinal Chemistry, 1997, 5, 2235, bearing a 3,4-dibenzyloxybenzyl (3,4-DBB) group at the 5′-end and a 2-hydroxyethylphosphate at the 3′-end, has high anti-HIV-1 activity and the least cytotoxicity in vitro and in vivo. In order to synthesize more potent hexadeoxyribonucleotides, we substituted phosphodiester (P---O) bonds in the 6-mer with the least phosphorothioate (P---S), phosphoramidate (P---N), or methylphosphonate (P---Me) bonds. When more than two P---N or P---Me bonds were introduced into a 6-mer, the phosphate-modified 6-mers had weak or no anti-HIV-1 activity, in spite of quadruplex structure formation. However, when P---S bonds were substituted for P---O bonds, anti-HIV-1 activity of their 6-mers did not dramatically decrease, compared with compounds substituted with P---N or P---Me bonds. The results suggest that the formation of a quadruplex structure is not always sufficient for anti-HIV-1 activity of the 6-mer, and that net negative charges derived from P---O or P---S bonds in the quadruplex are important for anti-HIV-1 activity. Moreover, among various phosphate-modified ODNs, we found that the anti-HIV-1 activity of ODN PS7 with only one P---S bond was the same as that of R-95288, both having a high stability in human plasma. 相似文献
109.
In zebrafish, apart from mononuclear melanophores, bi‐ and trinuclear melanophores are frequently observed; however, the manner in which multinucleation of these cells occurs during fish development remains unknown. Here, we analyzed the processes underlying multinucleation of zebrafish melanophores. Transgenic zebrafish in which melanophore nuclei were labeled with a histone H2B‐red fluorescent reporter protein were used to evaluate the distribution of mono‐, bi‐, and trinuclear melanophores in both the trunk and fin. Half of the melanophores examined were binuclear and approximately 1% were trinuclear. We compared cell size, cell motility, and survival rate between mono‐ and binuclear melanophores grown in a culture dish, and we found that cell size and survival rate were significantly larger in binuclear melanophores. We then analyzed the behavior of melanoblasts and melanophores from transgenic zebrafish using in vivo and in vitro live‐cell imaging. We detected division and differentiation of melanoblasts, as well as melanoblast nuclear division without subsequent cellular division. In addition, we observed cellular and nuclear division in melanophores, although these events were very infrequent in vitro. On the basis of our findings, we present a scheme for melanophore multinucleation in zebrafish. 相似文献
110.
The effect of solar radiation and monochromatic UV radiationon the motility of the filamentous cyanobacterium Phormidiumuncinatum was determined. Solar radiation (mid-day, in midsummerat a location near Lisboa, Portugal) was found to impair motilitywithin about 30 min. This effect is neither a result of a temperatureincrease nor of visible light. The spectral sensitivity determinedusing the Okazaki Largé Spectrograph shows the maximaleffectiveness of radiation of 300 nm. The short time requirementfor the response and the lack of any photoreactivation of motilityargues against DNA being the UV target. Investigations usingreagents diagnostic of superoxide free radicals and singletoxygen failed to confirm the involvement of photodynamic effectsas the molecular mechanism causing UV inhibition of motility.
3Present address: Biology Department, Faculty of Science, Universityof Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan (Received March 15, 1986; Accepted April 25, 1986) 相似文献