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PACS development has now reached a stage where it can clearly be stated that the technology for storage, networking and display in a fully digital environment is available. This is reflected by an already large and rapidly increasing number of PACS installations in USA, Western Europe and Japan. Such installations consist of a great variety of information systems, more or less interconnected, like PACS, HIS, RIS and other departmental systems, differing in both hardware and software. Various data - even if they only concern one person - are stored in different systems distributed in the hospital. The integration of all digital systems into a functional unit is determined by the radiologist's need of quick access to all relevant information regardless where it is stored. The interconnection and functional integration of all digital systems in the hospital determine the clinical benefits of PACS. This paper (1) describes the radiologist's requirements concerning this integration, and (2) presents some realistic solutions such as the Siemens ISI (Information System Interface), and a mobile viewing station for the wards (visitBox).  相似文献   
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A new radiolucent device for increased accuracy of CT-guided fine-needle punctures permits precise determination of the optimum angle, depth, and position of the fine needle, which can be preset from the data supplied on the CT monitor. Puncture and repeat scans for controlling the tip of the needle can be performed with the patient in a stationary position. The device is designed as a belt that holds a needle holder sheath and a goniometric scale, both of which can be moved to varying positions around the patient.  相似文献   
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S J Child  D E Hruby 《Virology》1992,191(1):262-271
When cells were infected with vaccinia virus in the presence of [3H]palmitic acid, radiolabel was incorporated into six viral proteins with apparent molecular weights of 92, 41, 37, 26, 17, and 14 kDa, all of which are expressed at late times during the infection cycle. The [3H]palmitate-labeled fatty acid moieties from the modified proteins were isolated, converted to p-nitrophenacyl derivatives, and subjected to reverse phase HPLC analysis which confirmed the identity of the fatty acid group as palmitic acid. Furthermore, the radiolabeled palmitate-protein bonds were sensitive to treatment with neutral hydroxylamine, suggesting that association of the fatty acid moieties with these proteins occurs via a thioester linkage. Previous studies by other investigators have identified the 37-kDa protein as the major antigen present in the outer membrane of extracellular enveloped virions, and demonstrated that the protein is modified by palmitic acid but is not glycosylated (G. Hiller and K. Weber J. Virol. (1985) 55, 651-659). Growth of vaccinia virus in the presence of tunicamycin indicated that the 41- and 26-kDa palmitylated proteins were also subject to modification by glycosylation, whereas like the 37-kDa protein, the 92-, 17-, and 14-kDa species did not appear to be glycosylated. Subcellular fractionation studies provided evidence that all of the viral palmitylated proteins were membrane-associated. Extraction of purified vaccinia virus with NP-40 and DTT demonstrated that the palmitylated proteins were associated with one of the viral membranes rather than the core of the virion. Viewing these results together with the previous reports of myristylated VV proteins (Franke et al. J. Virol. (1989) 63, 4285-4291), suggests that acylation of VV proteins represents a major modification pathway utilized by VV proteins during the assembly of progeny virions.  相似文献   
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In many cases, body temperature is altered in response to opioid agonists, but the direction, magnitude and time course of alteration vary with a number of factors. Body temperature may be subject to differential modification by different opioid receptor types. The authors examined the effect (i.c.v.) of the selective mu, delta and kappa opioid agonists, [D-Ala2, MePhe4, Gly5-ol] enkephalin (DAGO), [D-Pen2, D-Pen5] enkephalin and U50488H, respectively, on the body temperature of restrained and unrestrained rats. Each of the three opioid agonists produced a differentiable profile of body temperature changes. DAGO caused a primary decrease in body temperature of restrained rats and an increase in body temperature of unrestrained rats. The pretreatment dose of naloxone necessary to attenuate the hyperthermic response to DAGO of unrestrained rats was 10 times higher than that required to block the hypothermic response to DAGO in restrained rats. Low doses of both [D-Pen2, D-Pen5]enkephalin and U50488H caused a decrease in body temperature of both restrained and unrestrained rats. Hypothermic responses to U50488H were not blocked by naloxone, whereas hypothermic responses to [D-Pen2, D-Pen5]enkephalin in unrestrained rats were potentiated by naloxone. The results indicate that the three compounds modified body temperature by different means, suggesting activation of different opioid, and perhaps nonopioid, receptors. This may reflect a differential modulation of body temperature by endogenous opioids depending on the specific peptide released and the receptor type activated. Besides the physiologic implications, body temperature responses provided a sensitive pharmacologic measure for distinguishing the in vivo activity of different selective opioid agonists.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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Certain enkephalin analogues, including those which contain the conformationally restricted amino acid E-(2R,3S)-cyclopropylphenylalanine [2R,3S)-delta E Phe), have been shown to have high affinity for brain delta opioid receptors but are much less active in mouse vas deferens bioassays. To investigate whether there are differences between delta opioid receptors in brain and mouse was deferens, the ability of a selective delta opioid compound, [D-Pen2,pCl-Phe4,D-Pen5]enkephalin (pCl-DPDPE), and [D-Ala2,(2R,3S)-delta E Phe4,Leu5]enkephalin methyl ester (CP-OMe), to inhibit [3H]pCl-DPDPE binding in both rat brain and mouse vas deferens were measured. pCl-DPDPE recognized brain and mouse vas deferens binding sites with equal affinity, however, CP-OMe showed 33 fold lower affinity in mouse vas deferens compared to brain. This suggests that mouse vas deferens delta opioid receptors may be distinct from brain delta opioid receptors.  相似文献   
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The integrity of sperm DNA is crucial for the maintenance of genetic health. A major source of damage is reactive oxygen species (ROS) generation; therefore, antioxidants may afford protection to sperm DNA. The objectives of the study were, first, to measure the effects of antioxidant supplementation in vitro on endogenous DNA damage in spermatozoa using the single cell gel electrophoresis (comet) assay and, second, to assess the effect of antioxidant supplementation given prior to X-ray irradiation on induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll centrifugation in the presence of ascorbic acid (300, 600 microM), alpha tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5, 10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand breakage was measured using the comet assay. Sperm DNA was protected from DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60 microM) and urate (400 microM). These antioxidants provided protection from subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or ascorbate and alpha tocopherol together induced further DNA damage. Supplementation in vitro with the antioxidants ascorbate, urate and alpha tocopherol separately has beneficial effects for sperm DNA integrity.   相似文献   
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