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101.
One hundred twenty-three children with intrauterine growth retardation were prospectively followed from birth to 9 to 10 years of age in order to characterize their specific neurodevelopmental and cognitive difficulties and to identify clinical predictors of such difficulties. Perinatal biometric data and risk factors were collected. Outcome was evaluated at age 9 to 10 by neurodevelopmental, cognitive, and school achievement assessments. Sixty-three children served as controls who were appropriate for gestational age. Significant differences in growth (P < .001), neurodevelopmental scores (P < .001), intelligence quotient (IQ) (P < .0001), and school achievements measured by the Kaufmann Assessment Battery for Children (P < .001) were found between the children with intrauterine growth retardation and controls. Children with intrauterine growth retardation demonstrated a specific profile of neurocognitive difficulties at school age, accounting for lower school achievements. The best perinatal parameter predictive of neurodevelopment and IQ was the Cephalization Index (P < .001). Somatic catch-up growth at age 2 and at age 9 to 10 correlated with favorable outcome at 9 to 10 years of age.  相似文献   
102.
We propose to use infrared coherent two-dimensional correlation spectroscopy (2DCS) to characterize the fibril structure of Ab42, the dominant composition of Ab deposit, which is crucial for investigating its toxicity and aggregation mechanism. By optimizing the pulse polarization configurations with a genetic algorithm combined with sensitivity analysis, we obtained signals with well resolved cross-peak features attributed to the couplings within and between different structural motifs. These signals may provide new constraints for refining of the currently available NMR structure. Two-dimensional correlation spectroscopy also can differentiate the turn structure of Ab42 and other Ab derivatives.  相似文献   
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BACKGROUND: Sleep disturbance is a common subjective complaint of minor traumatic brain-injured (mTBI) patients, but little is known about the characteristics of sleep disturbance in adults years after the injury. METHODS: Polysomnographic (PSG) and multiple sleep latency test (MSLT) records of 26 mTBI adult patients with normal brain computerized tomography and negative encephalographic studies, no past history of CNS pathology, no premorbid or present major psychiatric diagnosis, and no sleep apnea syndrome were compared to a matched group of apparently healthy individuals (controls). RESULTS: Sleep patterns were disturbed in the mTBI patients. Their sleep architecture was altered, with significantly higher light-sleep non-rapid eye movement (NREM) stage 2 scores compared to controls (54.5+/-13.4% vs. 46.6+/-10.4%, respectively, p=0.03) and significantly lower REM sleep scores (21.2+/-8.4% vs. 25.4+/-4.5%, respectively, p=0.05). The MSLT findings documented significant excessive daytime episodes of falling asleep. CONCLUSIONS: Sleep disturbances of adult patients with chronic mTBI may manifest characteristic alterations in both timing and architecture of their sleep patterns. Sleep lab evaluations may help identify subgroups of mTBI patients who would probably benefit from treatment.  相似文献   
107.
Distinct networks of gamma-aminobutyric acidergic interneurons connected by electrical synapses can promote different patterns of activity in the neocortex. Cannabinoids affect memory and cognition by powerfully modulating a subset of inhibitory synapses; however, very little is known about the synaptic properties of the cannabinoid receptor-expressing neurons (CB(1)-positive irregular spiking [CB(1)-IS]) in the neocortex. Using paired recordings in neocortical slices, we 1st report here that synapses of CB(1)-IS cells, but not synapses of fast-spiking (FS) cells, are suppressed by release of endocannabinoids from pyramidal neurons. CB(1)-IS synapses were characterized by a very high failure rate that contrasted with the high reliability of FS synapses. Furthermore, CB(1)-IS cells received excitatory inputs less frequently compared with FS cells and made significantly less frequent inhibitory contacts onto local pyramids. These distinct synaptic properties together with their characteristic irregular firing suggest that CB(1)-IS cells play different role in neocortical function than that of FS cells. Thus, whereas the synaptic properties of FS cells can allow them to impose high-frequency rhythmic oscillatory activity, those of CB(1)-IS cells may lead to disruption of fast rhythmic oscillations. Our results suggest that activity-dependent release of cannabinoids, by blocking CB(1)-IS synapses, may alter the role of inhibition in neocortical circuits.  相似文献   
108.
C-reactive protein (CRP) was increased in patients with atrial fibrillation (AF). The aim of this study was to evaluate CRP after inducing AF in 39 patients undergoing electrophysiologic study (EPS). After a diagnostic EPS, programmed atrial stimulation with 3 extra stimuli from the right atrium was performed in all patients. CRP was measured before and 6 and 24 hours after the procedure. Patients in whom AF was induced were monitored for 24 hours. AF was induced in 18 of 39 patients. Twenty-one patients without a tachyarrhythmia constituted the control group. Groups were similar with regard to age, gender, incidences of hypertension and diabetes, and history of coronary artery disease. On average, AF lasted 4.8 hours, and spontaneous conversion to sinus rhythm was observed in all patients. There were no statistically significant differences with respect to baseline and 6-hour CRP values between groups. However, mean CRP at 24 hours was significantly higher in patients with AF compared with controls (10 +/- 11 and 3.9 +/- 4.2 mg/L; p = 0.04). In conclusion, induction of AF during EPS led to increased CRP. This finding suggested that increased CRP may be the consequence of AF.  相似文献   
109.
This study aims to examine the usefulness of spontaneous upper limb movements (ULM) as an early marker for predicting neurodevelopmental outcome in infants with intrauterine-growth retardation (IUGR). The assessment of general movements (GMs) during the first 20 weeks is an accepted method for early detection of brain dysfunction. During this period, spontaneous upper limb movements were examined in 32 infants with IUGR and 32 appropriate-for-gestational-age-matched controls. ULM (arms, forearms and hands) were scored as optimal or suboptimal by sequential videotape recordings in the writhing (term-2 weeks: score 0-5); early fidgety (9-11 weeks: score 0-6); and late fidgety (14-16 weeks: score 0-6) periods, and correlated with neurodevelopmental score at 2 years of age. The mean ULM score was lower in the IUGR infants than the controls (p<0.05) and in the IUGR group was lower in the infants with abnormal outcome (p<0.05). Significant correlations were found between ULM and 2-year neurodevelopmental scores in the IUGR group. The ULM during late-fidgety period was most predictive for 2-year neurodevelopmental score. No difference was found in the mean ULM score between the pre-term and term IUGR infants. We conclude that ULM score can serve as an early predictor for neurodevelopmental outcome at 2 years of age in infants with IUGR.  相似文献   
110.
Ibuprofen-induced ductus closure improves pulmonary mechanics and increases alveolar surface area in premature baboons compared with baboons with a persistent patent ductus arteriosus (PDA). Ibuprofen-treatment has no effect on the expression of genes that regulate pulmonary inflammation but does increase the expression of alpha-ENaC (the transepithelial sodium channel that is critical for alveolar water clearance). Although ligation eliminates the PDA, it does not improve pulmonary mechanics or increase alveolar surface area. We used preterm baboons (delivered at 67% of term gestation and ventilated for 14 d) to study whether the lack of beneficial effects, after PDA ligation, might be due to alterations in pulmonary gene expression. We found no differences in ventilation or oxygenation indices between animals that were ligated (n = 7) on day of life 6 and those that had a persistent PDA (n = 12) during the entire 14 d study. In contrast with no intervention, PDA ligation produced a significant increase in the expression of genes involved with pulmonary inflammation (COX-2, TNF-α, and CD14) and a significant decrease in alpha-ENaC sodium channel expression. We speculate that these changes may decrease the rate of alveolar fluid clearance and contribute to the lack of improvement in pulmonary mechanics after PDA ligation.  相似文献   
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