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41.
Genotype 2 hepatitis C virus (HCV) accounts for up to 30% of chronic HCV infections in Japan. The standard of care for patients with genotype 2 HCV – peginterferon and ribavirin for 24 weeks – is poorly tolerated, especially among older patients and those with advanced liver disease. We conducted a phase 3, open‐label study to assess the efficacy and safety of an all‐oral combination of the NS5B polymerase inhibitor sofosbuvir and ribavirin in patients with chronic genotype 2 HCV infection in Japan. We enrolled 90 treatment‐naïve and 63 previously treated patients at 20 sites in Japan. All patients received sofosbuvir 400 mg plus ribavirin (weight‐based dosing) for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after therapy (SVR12). Of the 153 patients enrolled and treated, 60% had HCV genotype 2a, 11% had cirrhosis, and 22% were over the aged 65 or older. Overall, 148 patients (97%) achieved SVR12. Of the 90 treatment‐naïve patients, 88 (98%) achieved SVR12, and of the 63 previously treated patients, 60 (95%) achieved SVR12. The rate of SVR12 was 94% in patients with cirrhosis and in those aged 65 and older. No patients discontinued study treatment due to adverse events. The most common adverse events were nasopharyngitis, anaemia and headache. Twelve weeks of sofosbuvir and ribavirin resulted in high rates of SVR12 in treatment‐naïve and previously treated patients with chronic genotype 2 HCV infection. The treatment was safe and well tolerated by patients, including the elderly and those with cirrhosis.  相似文献   
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Hadas R 《Lancet》2012,379(9832):2142-2143
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Strategies that increase homing to the bone marrow and engraftment efficacy of ex?vivo expended CD34(+) cells are expected to enhance their clinical utility. Here we report that nicotinamide (NAM), a form of vitamin B-3, delayed differentiation and increased engraftment efficacy of cord blood-derived human CD34(+) cells cultured with cytokines. In the presence of NAM, the fraction of CD34(+)CD38(-) cells increased and the fraction of differentiated cells (CD14(+), CD11b(+), and CD11c(+)) decreased. CD34(+) cells cultured with NAM displayed increased migration toward stromal cell derived factor-1 and homed to the bone marrow with higher efficacy, thus contributing to their increased engraftment efficacy, which was maintained in competitive transplants with noncultured competitor cells. NAM is a known potent inhibitor of several classes of ribosylase enzymes that require NAD for their activity, as well as sirtuin (SIRT1), class III NAD(+)-dependent-histone-deacetylase. We demonstrated that EX-527, a specific inhibitor of SIRT1 catalytic activity, inhibited differentiation of CD34(+) cells similar to NAM, while specific inhibitors of NAD-ribosylase enzymes did not?inhibit differentiation, suggesting that the NAM effect is SIRT1-specific. Our findings suggest?a critical function of SIRT1 in the regulation of hematopoietic stem cell activity and imply the?clinical utility of NAM for ex?vivo expansion of functional CD34(+) cells.  相似文献   
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Stress and episodic memory impairment have previously been associated. Acute stress disorder (ASD) is a maladaptive stress response, which develops in some individuals following traumatic life events. Recently, the authors demonstrated a specific deficit in associative memory for emotionally neutral stimuli in ASD and posttraumatic stress disorder (PTSD). This study further tested the relationship between this memory impairment and the course of ASD. We assessed new learning and memory for item and associative information in patients diagnosed with ASD (n=14) and matched trauma naïve controls (n=14). Memory performance and posttraumatic symptoms were examined for approximately 1 and 10 week periods following the traumatic experience. In the two experiments, participants studied a list of stimuli pairs (verbal or visual) and were then tested for their memory of the items (item recognition test), or for the association between items in each pair (associative recognition test). In both experiments, ASD patients showed a marked associative memory deficit compared to the control group. After 10 weeks, ASD symptoms were resolved in most patients. Interestingly, their performance on associative recognition for verbal stimuli improved, while the associative deficit for visual stimuli remained unchanged. Potential mechanisms underlying such an associative memory deficit in post-trauma patients are discussed.  相似文献   
46.
The neurotransmitter dopamine (DA) plays a critical role in both priming‐and cue‐induced reinstatement of extinguished drug‐seeking behavior, but its role in stress‐induced reinstatement is less clear. Our laboratory has recently demonstrated that systemic administration of the DA D1‐like receptor antagonist, SCH 23390, attenuates acute food deprivation (FD) stress‐induced reinstatement. The current study was designed to elucidate the brain regions critical to the effect of SCH 23390 on FD stress‐induced reinstatement. Rats were trained to press a lever to self‐administer heroin (0.1 mg/kg/inf) over a period of 10 days. Following training, heroin was removed leading to an extinction of lever pressing. Next, rats were tested for reinstatement twice, under extinction conditions: once following 21–48 h FD; and once under sated conditions. Prior to testing, SCH 23390 was administered into the nucleus accumbens (NAc) shell (0.0, 0.3, 0.6 μg/side), NAc core (0.0, 0.3, 0.6 μg/side), dorsomedial prefrontal cortex (dmPFC; 0.0, 0.2, 2.0 μg/side), ventromedial prefrontal cortex (vmPFC; 0.0, 2.0 μg/side) or basolateral amygdala (BLA; 0.0, 1.0, 2.0 μg/side). An attenuation of FD‐induced reinstatement of heroin seeking was seen in rats injected with SCH 23390 into the NAc shell, dmPFC or BLA, but not into the NAc core or the vmPFC. These findings support the hypothesis that DA transmission through the DA D1‐like receptors plays a critical role in stress‐induced reinstatement of heroin seeking.  相似文献   
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Salmonella enterica serovar Virchow is highly prevalent in humans and farm animals in Israel. In addition to high rates of resistance to multiple antibiotics, this serovar exhibits a high incidence of resistance to nalidixic acid. More than 90% of Salmonella serovar Virchow isolates of human and poultry origin obtained from 1997 to 2004 were resistant to nalidixic acid (MIC > or = 128 microg/ml), with reduced susceptibility to ciprofloxacin (MIC between 0.125 and 0.250 microg/ml). Most isolates belonged to two predominant, closely related pulsed-field gel electrophoresis image types. Investigation of the mechanisms of quinolone resistance revealed that this pathogen probably emerged from a parental clone that overproduced the AcrAB efflux pump and had a single point mutation in gyrA leading to the Asp87Tyr substitution. The close resemblance between human and poultry isolates points to poultry as a likely source of Salmonella serovar Virchow in the food chain.  相似文献   
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OBJECTIVE: To examine the feasibility of diagnosing congenital cardiac defects between 11 and 14 weeks' gestation in a high-risk population. METHODS: Fetal echocardiography was first offered at 11 to 14 weeks' gestation to all patients at risk for congenital heart defects. Echocardiography performed at 11 to 14 weeks with normal results was repeated at 14 to 16 and 20 to 24 weeks. Final diagnoses of cardiac anomalies that had been observed at 11 to 14 weeks were established at 14 to 16 weeks or later Fetal echocardiography performed at 14 to 16 weeks with normal results was repeated at 20 to 24 weeks. Ascertainment of cardiac anomalies was obtained by postnatal echocardiography or pathologic examination of the fetal heart after termination of pregnancy. Most of the examinations were performed transvaginally until 16 weeks. The transabdominal approach was used at this stage only when patients refused the transvaginal examination or because of technical difficulties. Three hundred ninety-two fetal echocardiographic examinations were performed between 11 and 14 weeks' gestation; 438 examinations were performed between 14 and 16 weeks; and 777 examinations were performed between 20 and 24 weeks. The major indications for fetal echocardiography at 11 to 14 weeks were maternal diabetes and previous pregnancy with congenital heart defects. RESULTS: Six of 7 major fetal cardiac anomalies were detected. The only major cardiac anomaly that was not detected between 11 and 14 weeks was correctly diagnosed at 22 weeks. Only 1 of 5 minor fetal cardiac anomalies was detected between 11 and 14 weeks. Another 2 minor fetal cardiac anomalies were detected at 23 weeks. Four incorrect diagnoses of minor cardiac anomalies were excluded on repeated fetal echocardiography between 20 and 24 weeks. CONCLUSIONS: The initial attempt to diagnose congenital heart defects should be offered at 11 to 14 weeks' gestation.  相似文献   
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