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11.
Analysis of orthologous gene expression between human pulmonary adenocarcinoma and a carcinogen-induced murine model
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![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Stearman RS Dwyer-Nield L Zerbe L Blaine SA Chan Z Bunn PA Johnson GL Hirsch FR Merrick DT Franklin WA Baron AE Keith RL Nemenoff RA Malkinson AM Geraci MW 《The American journal of pathology》2005,167(6):1763-1775
Human adenocarcinoma (AC) is the most frequently diagnosed human lung cancer, and its absolute incidence is increasing dramatically. Compared to human lung AC, the A/J mouse-urethane model exhibits similar histological appearance and molecular changes. We examined the gene expression profiles of human and murine lung tissues (normal or AC) and compared the two species' datasets after aligning approximately 7500 orthologous genes. A list of 409 gene classifiers (P value <0.0001), common to both species (joint classifiers), showed significant, positive correlation in expression levels between the two species. A number of previously reported expression changes were recapitulated in both species, such as changes in glycolytic enzymes and cell-cycle proteins. Unexpectedly, joint classifiers in angiogenesis were uniformly down-regulated in tumor tissues. The eicosanoid pathway enzymes prostacyclin synthase (PGIS) and inducible prostaglandin E(2) synthase (PGES) were joint classifiers that showed opposite effects in lung AC (PGIS down-regulated; PGES up-regulated). Finally, tissue microarrays identified the same protein expression pattern for PGIS and PGES in 108 different non-small cell lung cancer biopsies, and the detection of PGIS had statistically significant prognostic value in patient survival. Thus, the A/J mouse-urethane model reflects significant molecular details of human lung AC, and comparison of changes in orthologous gene expression may provide novel insights into lung carcinogenesis. 相似文献
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Identification of Brucella by Ribosomal-Spacer-Region PCR and Differentiation of Brucella canis from Other Brucella spp. Pathogenic for Humans by Carbohydrate Profiles 总被引:3,自引:0,他引:3
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Karen F. Fox Alvin Fox Madan Nagpal Paul Steinberg Karen Heroux 《Journal of clinical microbiology》1998,36(11):3217-3222
Molecular and chemical characteristics often provide complementary information in the differentiation of closely related organisms. The genus Brucella consists of a highly conserved group of organisms. Identification of the four species pathogenic in humans (Brucella melitensis, Brucella abortus, Brucella suis, and Brucella canis) is problematic for many clinical laboratories that depend primarily on serology and phenotypic characteristics to differentiate species. PCR amplification of the 16S-23S ribosomal DNA interspace region was evaluated for species-specific polymorphism. B. abortus, B. melitensis, B. suis, and B. canis produced identical PCR interspace profiles. However, these PCR products were unique to brucellae, allowing them to be readily distinguished from other gram-negative bacteria (including Bartonella spp. and Agrobacterium spp.). Carbohydrate profiles differentiated B. canis from the other three Brucella species due to the absence of the rare amino sugar quinovosamine in the three other species. PCR of the rRNA interspace region is useful in identification of the genus Brucella, while carbohydrate profiling is capable of differentiating B. canis from the other Brucella species. 相似文献
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O'Goiman's (1979) criticisms of the orienting response (OR) significance hypothesis are not well-founded. The hypothesis is not based solely on electrodermal data—studies reporting significance effects for heart rate and pupillary OR are cited. The hypothesis does not discard novelty but suggests that an interaction between uncertainty and significance triggers OR. Differential reactivity across OR components reflects stimulus- and individual-response factors, and does not require separate “significance registers.” Since the hypothesis specifically maintains that appraisals of stimulus significance affect the OR, not the mere fact of cognitive appraisal per se, no general “cognitive appraisal effect” was ever expected. O'Gorman confuses the difficulty of estimating the subject's spontaneous judgments of significance with the relative ease of manipulating significance in the laboratory. He considers classic OR theory more “objective” only because he fails to look closely enough at the complex judgmental processes involved in stimulus intake, model building, and matching functions. O'Gorman's contentions of different initial- and test-ORs, and of a simple additive relationship between significance and OR, lack supportive data and are challenged by available evidence. Literature is cited suggesting that: a) scanning is continuously biased toward the detection of significant stimuli; b) detection of a sgnificant stimulus feature triggers increased information scanning, increasing the possibility that previously unrecognized uncertainty will be detected, and c) lowers the criterion level of the OR “threshold,” increasing the likelihood of OR if uncertainty is detected. Evidence is cited suggesting that the significance-OR, and perhaps attention in general, is mediated by neocortical-limbic interaction, the limbic' “motivational” evaluator of stimulus input steering and switching neocortical “intellectual” analyzers of stimulus pattern. 相似文献
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In vitro assays demonstrate photoreactivating enzyme activity in extracts of Candida pseudotropicalis but not in extracts of Candida albicans, Candida stellatoidea, or Candida tropicalis. 相似文献
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Effects of handling stimuli given to the rat during pre-weaning period were investigated on plasma immunoreactive (ir) adrenocorticotropin (ACTH) level after electric footshocks or novel audiovisual stimuli in adult life. Plasma ir-ACTH levels after footshocks did not significantly differ between non-handled control and previously handled rats, while the hormone level after novel audiovisual stimuli was significantly lower in handled than in the control rats. These results demonstrate that pre-weaning handling reduces ACTH response to novel audiovisual stimuli but not to footshocks in adult life, and thus suggest the possibility that stress during pre-weaning period affects differentially the developmental plasticity of the hypothalamo-pituitary axis. 相似文献
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The nucleotide sequence and genome organization of a new member of Caliciviridae was determined. Cell culture inoculated with fecal matter from walrus was used to recover fragments of a new virus by Suppression Subtractive Hybridization (SSH). The isolate was identified as a member of the Vesivirus genus of Caliciviridae and designated the name Walrus Calicivirus (WCV). Sets of PCR primers spanning the entire putative genome were designed using known sequences of other vesiviruses. The assembled genome was 8289 nucleotides (nt) long and shared no more than 87% identity with sequences of the other members of the genus Vesivirus. The largest open reading frame (ORF1) between positions 4-5646 encoded a polyprotein. ORF2, found at position 5652-7778, encoded a putative capsid protein. ORF3 overlapped ORF2 and encoded a small basic protein. Comparative analysis of multiple caliciviral capsid proteins was performed to propose a uniform capsid structural organization for this viral family. 相似文献
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Potentiation of vasopressin secretion by footshocks in rats 总被引:2,自引:0,他引:2
Effects of footshocks (FS) on antidiuretic hormone (vasopressin, VP) in the plasma were studied in rats. Continuously applied FS of 60 s period with 5 ms pulses at 50 Hz frequency significantly increased VP as well as adrenocorticotrophic hormone (ACTH) in the plasma in a time- and shock intensity-dependent manner. Contrarily, the 50 Hz FS of 2 s period as repeated intermittently at every 15 s for over the period of 2, 10, and 30 min were much less effective for increasing plasma VP, whereas these intermittent FS increased plasma ACTH to an extremely high level. During the inter-shock intervals of 13 s between successive two shock periods rats exhibited a "freezing" behavior. Hypertonic saline or urethane injected I.P. immediately after termination of the intermittent FS significantly increased VP as well as ACTH in the plasma. These data clearly indicate that FS potentiate VP secretion and suggest the possibility that emotional stress may suppress the noxious stimuli-induced VP secretion. 相似文献