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951.
952.
Complementation of the protein transport defect of an Escherichia coli secY mutant (secY24) by Bacillus subtilis secY homologue 总被引:6,自引:0,他引:6
Bacillus subtilis SecY homologue shares 41.3% homology with that of E. coli and remarkably higher homologous regions (more than 80%) are present in the four cytoplasmic regions [(1990) J. Biochem. 107, 603-607]. Based on the formation of the mature form of OmpA in E. coli, we have shown that the protein transport defect of the E. coli secY mutant (secY24) is complemented by the gene product from the B. subtilis secY homologue, which is expressed under the lac promoter control. However, B. subtilis SecY could not restore growth of the E. coli mutant at nonpermissive temperature. 相似文献
953.
Eizo Takashima Hiroyuki Yamada Tetsuo Yamashita Kazunobu Matsushita & Kiyoshi Konishi 《FEMS microbiology letters》2010,302(1):52-57
The qpo gene of Aggregatibacter actinomycetemcomitans encodes a triheme c -containing membrane-bound enzyme, quinol peroxidase (QPO) that catalyzes peroxidation reaction in the respiratory chain and uses quinol as the physiological electron donor. The QPO of A. actinomycetemcomitans is the only characterized QPO, but homologues of the qpo gene are widely distributed among many gram-negative bacteria, including Haemophils ducreii, Bacteroides fragilis , and Escherichia coli . One-third of the amino acid sequence of QPO from the N-terminal end is unique, whereas two-thirds of the sequence from the C-terminal end exhibits high homology with the sequence of the diheme bacterial cytochrome c peroxidase. In order to obtain sufficient protein for biophysical studies, the present study aimed to overproduce recombinant QPO (rQPO) from A. actinomycetemcomitans in E. coli . Coexpression of qpo with E. coli cytochrome c maturation ( ccm ) genes resulted in the expression of an active QPO with a high yield. Using purified rQPO, we determined the midpoint reduction potentials of the three heme molecules. 相似文献
954.
Kazuhiro Kitajima Utaru Tanaka Yoshiko Ueno Tetsuo Maeda Yuko Suenaga Satoru Takahashi Masashi Deguchi Yoshiya Miyahara Yasuhiko Ebina Hideto Yamada Masakatsu Tsurusaki Yukihisa Tamaki Kazuro Sugimura 《PloS one》2015,10(1)
Background and Purpose
To investigate the diagnostic performance of diffusion-weighted imaging (DWI) and contrast-enhanced imaging in combination with T2-weighted imaging (T2WI) for magnetic resonance imaging (MRI) evaluation of intrapelvic recurrence of gynecological malignancies.Materials and Methods
Sixty-two patients with suspected intrapelvic recurrence of gynecological malignancies underwent pelvic MRI including T2WI DWI, and contrast-enhanced imaging. Diagnostic performance for detection of local recurrence, pelvic lymph node and bone metastases, and peritoneal lesions was evaluated by consensus reading of two experienced radiologists using a 5-point scoring system, and compared among T2WI with unenhanced T1-weighted imaging (T1WI) (protocol A), a combination of protocol A and DWI (protocol B), and a combination of protocol B and contrast-enhanced imaging (protocol C). Final diagnoses were obtained by histopathological examinations, radiological imaging and clinical follow-up for at least 6 months. Receiver operating characteristic (ROC) analysis and McNemar test were employed for statistical analysis.Results
Locally recurrent disease, lymph node recurrence, peritoneal dissemination and bone metastases were present in 48.4%, 29.0%, 16.1%, and 6.5% of the patients, respectively. The patient-based sensitivity, specificity, accuracy, and area under the ROC curve (AUC) for detection of intrapelvic recurrence were 55.0, 81.8, 64.5% and 0.753 for protocol A, 80.0, 77.3, 79.0% and 0.838 for protocol B, and 80.0, 90.9, 83.9% and 0.862 for protocol C, respectively. The sensitivity, accuracy, and AUC were significantly better for protocols B and C than for protocol A (p<0.001). There was no significant difference between protocols B and C.Conclusion
MRI using a combination of DWI and T2WI gives comparatively acceptable results for assessment of intrapelvic recurrence of gynecological malignancies. 相似文献955.
Yutaka Fujiwara Shogo Kobayashi Hiroaki Nagano Masashi Kanai Etsuo Hatano Masanori Toyoda Tetsuo Ajiki Yuki Takashima Kenichi Yoshimura Akinobu Hamada Hironobu Minami Tatsuya Ioka 《PloS one》2015,10(12)
Background
Biliary tract cancer (BTC) patients who have undergone surgical resection with major hepatectomy cannot tolerate the standard gemcitabine regimen (1,000 mg/m2 on days 1, 8, and 15 every 4 weeks) due to severe toxicities such as myelosuppression. Our dose-finding study of adjuvant gemcitabine therapy for biliary tract cancer following major hepatectomy determined that the recommended dose is 1,000 mg/m2 on days 1 and 15 every 4 weeks. Here, we evaluate the pharmacokinetics and pharmacodynamics of gemcitabine in these subjects.Methods
We evaluated BTC patients scheduled to undergo surgical resection with major hepatectomy followed by gemcitabine therapy. A pharmacokinetic evaluation of gemcitabine and its main metabolite, 2′,2′-difluorodeoxyuridine (dFdU), was conducted at the initial administration of gemcitabine, which was given by intravenous infusion over 30 min at a dose of 800–1,000 mg/m2. Physical examination and adverse events were monitored for 12 weeks.Results
Thirteen patients were enrolled from August 2011 to January 2013, with 12 ultimately completing the pharmacokinetic study. Eight patients had hilar cholangiocarcinoma, three had intrahepatic cholangiocarcinoma, and one had superficial spreading type cholangiocarcinoma. The median interval from surgery to first administration of gemcitabine was 65.5 days (range, 43–83 days). We observed the following toxicities: neutropenia (n = 11, 91.7%), leukopenia (n = 10, 83.3%), thrombocytopenia (n = 6, 50.0%), and infection (n = 5, 41.7%). Grade 3 or 4 neutropenia was observed in 25% (n = 3) of patients. There were differences in clearance of gemcitabine and dFdU between our subjects and the subjects who had not undergone hepatectomy.Conclusion
Major hepatectomy did not affect the pharmacokinetics of gemcitabine or dFdU.Trial Registration
UMIN-CTR in (JPRN) UMIN000005109 相似文献956.
Yoshinobu Yokoyama Takuya Miyagi Hayato Hikita Teppei Yoshioka Kaori Mukai Takatoshi Nawa Ryotaro Sakamori Kazuyoshi Ohkawa Naoki Hiramatsu Takeshi Takahashi Hiroshi Suemizu Akihide Ryo Tomohide Tatsumi Tetsuo Takehara 《PloS one》2015,10(12)
Background & Aims
At least eight genotypes of Hepatitis B virus (HBV) have been identified. HBV genotype C is the most common genotype in Japan, although the incidence of HBV genotype A is increasing. The reason underlying the differences in viral multiplication of the HBV genotypes is unclear, especially in vivo. The purpose of this study was to elucidate the differences in HBV load and the persistence of viremia in vivo between genotypes A and C.Methods
Immunodeficient NOG mice were transfected by hydrodynamic injection with the HBV expression plasmids pHBA1.2 or pHBC1.2, which contain overlength (1.2-mer) copies of the genomes of HBV genotype A or C, respectively.Results
One day after transfection, the number of HBcAg-positive hepatocytes and serum HBV DNA levels were similar between mice transfected with pHBA1.2 and pHBC1.2. Serum levels of HBV DNA, HBsAg and HBeAg in mice transfected with pHBA1.2 were maintained over 5 months. In contrast, those in mice with pHBC1.2 gradually decreased over time and reached undetectable levels within 3 months after transfection. HBcAg-stained hepatocytes were detected in mice transfected with pHBA1.2, but not pHBC1.2, 5 months post-transfection. Double-staining immunohistochemistry revealed that the number of cleaved caspase3-stained, HBcAg-positive hepatocytes in the pHBC1.2-transfected mice was higher than in the pHBA1.2-transfected mice 3 days post-transfection. Moreover, the plasmid DNA and covalently closed circular DNA levels were decreased in the livers of pHBC1.2-transfected mice. These results suggested that hepatocytes expressing HBV genotype C were eliminated by apoptosis in the absence of immune cells more often than in hepatocytes expressing HBV genotype A.Conclusions
Immunodeficient mice transfected with HBV genotype A develop persistent viremia, whereas those transfected with HBV genotype C exhibit transient viremia accompanied by apoptosis of HBV-expressing hepatocytes. This differences may affect the clinical courses of patients infected with HBV genotypes A and C. 相似文献957.
958.
Koyama Takashi Sato Shinichi Kanbayashi Takashi Kondo Hideaki Watanabe Hiroyuki Nishino Seiji Shimizu Tetsuo Ito Hiroshi Ono Kyoichi 《Sleep and biological rhythms》2015,13(1):57-67
Sleep and Biological Rhythms - A simplified diagnostic/monitoring instrument for use in primary screening for sleep-disordered breathing (SDB) has been desired. This study was designed to assess... 相似文献
959.
960.
Diterpenoid phytoalexin factor,a bHLH transcription factor,plays a central role in the biosynthesis of diterpenoid phytoalexins in rice
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