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71.
In the light of issues discussed during 24th Session of Codex Committee on Methods of Analysis and Sampling that was held in Budapest, 18-22 November 2002, the current activity of this Committee is presented. More detailed information about some of the most advanced or interesting documents is included, i. e. Proposed Draft General Guidelines On Sampling, Harmonized IUPAC Guidelines for Single-Laboratory Validation of Methods of Analysis, Consideration of methods for the detection and identification of food derived from biotechnology.  相似文献   
72.
Cisplatin has a significant role in the treatment of selected human tumors including advanced melanoma, but new platinum compounds are still in focus of search for better properties. Modern drug design is often based on studies detecting the abilities of tested drug to induce apoptosis and disturb cell cycle. Aim of the study was to establish the influence of a platinum complex Pt-rib-1 on cell cycle and apoptosis occurrence in mouse melanoma B16 and ClS91 cells. Pt-rib-1 is a ribavirin derivative. previously characterized and described as cytotoxic to B16 and ClS91 mouse melanoma cells in vitro. The new platinum complex (Pt-rib-1); cis- dichloro (dimethylsulphoxide) (1- beta- D-ribofuranosyl- 1,2,4-triazolo -3- carboxyamide) platinum (II) was supplied. Cisdiaminodichloroplatinum (II), (cisplatin) was used in control groups. To detect apoptotic and necrotic cells, Annexin V- conjugated with fluorescein isothiocyanate (Annexin V-FITC, Immunotech) and propidium iodide (IP, Immunotech) were used. Apoptosis detection were done using fluorescence microscopy and flow cytometry. The total DNA content within the cell indicated phase of the cell cycle. DNA content was measured using flow cytometry. Values given represent the mean from three determinations. Results were presented as mean +/- standard deviation (SD). Statistical analysis was done using t-Student test. There were 70.4% of apoptotic cells in the ClS91 culture after 24 h incubation with Pt-rib-1 at a concentration of 2.04 x 10(-3) M (4 x IC50). In B16 group, 83.2 per cent of apoptotic cells was found after 24h incubation with Pt-rib-1 at high concentration (2.30 x 10(-3) M). A 24-h experiment shows a threshold at a concentration higher than 3 x IC50 responsible for apoptosis induction in B16 and ClS91 cells. After 48 h incubation with Pt-rib-1 the per cent of apoptotic cells increased gradually with rising concentrations of Pt-rib-1 up to a final concentration of 2.04 x 10(-3) M and 0.92 x 10(-3) M in ClS91 and B16 groups, respectively. Cell accumulation was observed in S phase after 48 h incubation with Pt-rib-1. The per cent of cells in S phase increased from 31 to 51.1% and 38.8 to 50.0% in ClS91 and B16 culture, respectively. There were no B16 and ClS91 cells in G2/M phase after incubation with higher concentrations of Pt-rib-1 (from 0.2 to 2.0 x 10(-5) M/dm3). Pt-rib-1 partially exhibits action of cisplatin. which has no specific influence on cell cycle and ribavirin. probably responsible for DNA synthesis delay.  相似文献   
73.
A series of cyclophosphazene crown ether derivatives bearing aziridinyl (ethylene imine) units and also 2-naphthyl or anthraquinone groups as co-substituents has been synthesized and their cytostatic activity against the panel of eight cancer cells in vitro has been studied. The substituents used exhibit different activities: alkylation (aziridinyl groups) and intercalation (naphtyl, anthraquinone groups) against DNA. These both interactions are supposed to enhance the efficiency of the cyclophosphazene crown ether derivatives studied as cytotoxic agents.  相似文献   
74.
The opioid peptide dimmer biphalin [(Tyr-D-Ala-Gly-Phe-NH-)(2)] has high potency both in vivo and in vitro. Its antinociceptive activity depends on the route of administration: the lowest potency is after subcutaneous, and the highest after intrathecal or inracerebroventricular administration. We tested the analgesic activity of biphalin in a wide range of doses after intrathecal administration to rats. Doses as low as 0.005 nmol produced significant analgesia. Increasing the dose up to 2 nmol elevated and prolonged antinociception without any evident side effects, indicating that biphalin is an extremely potent opioid after intrathecal application with a wide therapeutic window. The highest dose tested (20 nmol) produced full analgesia and body rigidity lasting 2-3 h. After muscle tone returned to normal, antinociception lasted for several more hours. During these studies we observed a correlation between responses to biphalin and catheter placement. Postmortem verification of catheter placement revealed that in those rats in which high-dose biphalin did not produce analgesia or muscle rigidity, the catheter was positioned incorrectly or the flow of drug solution was obstructed. Therefore, a secondary conclusion is that assessment of transient rigidity after administration of a high dose of biphalin may be used as an easy method to confirm intrathecal placement of the catheter.  相似文献   
75.
The ipsilateral connections of motor areas of galagos were determined by injecting tracers into primary motor cortex (M1), dorsal premotor area (PMD), ventral premotor area (PMV), supplementary motor area (SMA), and frontal eye field (FEF). Other injections were placed in frontal cortex and in posterior parietal cortex to define the connections of motor areas further. Intracortical microstimulation was used to identify injection sites and map motor areas in the same cases. The major connections of M1 were with premotor cortex, SMA, cingulate motor cortex, somatosensory areas 3a and 1, and the rostral half of posterior parietal cortex. Less dense connections were with the second (S2) and parietal ventral (PV) somatosensory areas. Injections in PMD labeled neurons across a mediolateral belt of posterior parietal cortex extending from the medial wall to lateral to the intraparietal sulcus. Other inputs came from SMA, M1, PMV, and adjoining frontal cortex. PMV injections labeled neurons across a large zone of posterior parietal cortex, overlapping the region projecting to PMD but centered more laterally. Other connections were with M1, PMD, and frontal cortex and sparsely with somatosensory areas 3a, 1-2, S2, and PV. SMA connections were with medial posterior parietal cortex, cingulate motor cortex, PMD, and PMV. An FEF injection labeled neurons in the intraparietal sulcus. Injections in posterior parietal cortex revealed that the rostral half receives somatosensory inputs, whereas the caudal half receives visual inputs. Thus, posterior parietal cortex links visual and somatosensory areas with motor fields of frontal cortex.  相似文献   
76.
The Hamilton Rating Scale for Depression (HRSD) is the most frequently used measure of outcome in antidepressant efficacy trials. More than a decade ago, a consensus panel recommended that remission be defined on the 17-item version of the HRSD as a cutoff 相似文献   
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We examined the influence of CP 154,526, a selective antagonist of corticotropin-releasing factor (CRF)1 receptors, in the locomotor, sensitizing, discriminative stimulus and rewarding effects of cocaine, as well as on the cocaine-induced reinstatement of cocaine-seeking behavior in male Wistar rats. CP 154,526 in doses of 5, 10 and 20 mg/kg, which did not affect basal locomotor activity, dose-dependently reduced the hyperactivation evoked by cocaine. To assess the effects of CP 154,526 on the expression of cocaine sensitization, the rats were injected with either saline or cocaine (10 mg/kg) for 5 days, and were then challenged with cocaine (10 mg/kg) after pretreatment with saline or CP 154,526 on day 5 of withdrawal. The cocaine-induced hyperactivity in sensitized rats was reduced by CP 154,526 (10 and 20 mg/kg). In rats trained to discriminate cocaine (10 mg/kg) from saline, pretreatment with CP 154,526 (5-20 mg/kg) did not affect the cocaine (1.25-10 mg/kg)-induced discriminative stimulus effects. In a self-administration model, the rats were trained to self-administer cocaine (0.5 mg/kg/infusion) in the FR 5 schedule of reinforcement. Administration of CP 154,526 (10-20 mg/kg) did not alter the rewarding effects of cocaine, assessed as the number of active-lever presses and infusions; however, following a 10-day extinction phase, CP 154,526 (5-20 mg/kg) significantly decreased in a dose-dependent manner the cocaine (10 mg/kg) priming-induced reinstatement of cocaine-seeking behavior. The present study implies that CRF1 receptors control the expression of cocaine hyperactivation and sensitization as well as the cocaine-induced relapse behavior, but do not play any role in cocaine discrimination and self-administration. These findings may suggest that CRF1 receptor antagonists should be considered as possible medications in the treatment of cocaine addiction.  相似文献   
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