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991.
CONTEXT: The clinical, neuroradiological, and biological characteristics of the so-called acquired hepatocerebral degeneration have not yet been fully determined and its frequency remains largely uncertain. OBJECTIVES: To prospectively study the prevalence of extrapyramidal symptoms in patients with moderate to severe cirrhosis of various causes, to delineate the main neurological features of the condition, and to establish correlations with neuroradiological and biological findings. PATIENTS AND METHODS: During a 1-year period, all consecutive patients with cirrhosis who were potential candidates for liver transplantation were screened for extrapyramidal features. When extrapyramidal features were present, further workup included a detailed neurological examination, magnetic resonance imaging of the brain, a comprehensive battery of neuropsychological tests, extensive blood tests, and, in some cases, cerebrospinal fluid analysis. SETTING: A community-based hospital. RESULTS: From 51 patients screened, 11 (21.6%) exhibited moderate to severe parkinsonism sometimes associated with focal dystonia. Typical features included rapid progression over months, symmetric akinetic-rigid syndrome, postural but not resting tremor, and early postural and gait impairment. Neuropsychiatric manifestations were minimal. Some patients were responsive to levodopa therapy. In all patients, magnetic resonance imaging scans showed striking hyperintensities on T1-weighted images typically involving the substantia nigra and the globus pallidus bilaterally. Whole blood and cerebrospinal fluid manganese concentrations were severalfold above the reference range. CONCLUSIONS: Cirrhosis-related parkinsonism may represent a unique, consistent, and common subset of acquired hepatocerebral degeneration, whose features are permanent and entirely different from acute hepatic encephalopathy episodes. This form of parkinsonism can be clearly distinguished from other forms of parkinsonism of middle to advanced age, based on a suggestive association of clinical, neuroradiological, and biological abnormalities. Our findings support the concept of the toxic effects of manganese being the major determinant of basal ganglia dysfunction leading to the predominantly extrapyramidal central nervous system manifestations of cirrhosis observed in these patients.  相似文献   
992.
Conventional suture repair of peripheral nerves results in a fibrotic reaction that is detrimental to nerve regeneration. As an alternative procedure known as "laser-assisted" repair, a laser can be used, along with a reduced number of sutures, to reanastomose served peripheral nerves. To explore the long-term implications of this technique, the right sciatic nerves of Sprague-Dawley rats were surgically cut and reanastomosed either by means of four epineurial sutures or two epineurial sutures and CO2 laser welds. Tensile strength, electrophysiology, histology, and functional studies were performed up to 11 months postoperatively. Tensile strength measurements indicate no long-term disadvantage with the laser-assisted technique, although the short-term tensile strength is lower than with conventional suture repair. The conduction velocities of the repaired nerves were similar for both techniques; however, laser-assisted repaired nerves were found to have lower stimulation thresholds and reduced branching compared to the suture repaired nerves. The measured functional recovery was similar for both repair techniques.  相似文献   
993.
Aim: Because New Caledonia is geographically isolated from the nearest cardiac surgical centre, surgical closure of ductus arteriosus is not performed in very low‐birthweight (VLBW) infants who have a persistent patent ductus in spite of having undergone treatment with ibuprofen. This study aimed at investigating the possible effect of persistent patent ductus in VLBW infants. Methods: The study included 177 VLBW infants born at 25–31 weeks of gestation from January 2006 to May 2011. Mortality and major morbidities were compared between infants with a persistent patent ductus (n = 33) and those without it (n = 104). Statistical associations between potential neonatal risk factors and significant morbidities were identified using multivariate regression analyses. Results: Rates of mortality and major morbidities, including the rate of bronchopulmonary dysplasia, necrotizing enterocolitis, intraventricular haemorrhage grades I–II and III–IV, periventricular leucomalacia, late‐onset infections and failure of hearing screening, were insignificantly higher in VLBW infants with a persistent patent ductus than in those without it. Conclusion: This study adds further evidence that persistent patent ductus arteriosus has no significant effect on mortality and morbidity in VLBW infants born at ≥25 weeks’ gestational age.  相似文献   
994.
Maternal occupational pesticide exposure during pregnancy and/or paternal occupational pesticide exposure around conception have been suggested to increase risk of leukemia in the offspring. With a view to providing insight in this area we pooled individual level data from 13 case‐control studies participating in the Childhood Leukemia International Consortium (CLIC). Occupational data were harmonized to a compatible format. Pooled individual analyses were undertaken using unconditional logistic regression. Using exposure data from mothers of 8,236 cases, and 14,850 controls, and from fathers of 8,169 cases and 14,201 controls the odds ratio (OR) for maternal exposure during pregnancy and the risk of acute lymphoblastic leukemia (ALL) was 1.01 [95% confidence interval (CI) 0.78, 1.30] and for paternal exposure around conception 1.20 (95% 1.06, 1.38). For acute myeloid leukemia (AML), the OR for maternal exposure during pregnancy was 1.94 (CI 1.19, 3.18) and for paternal exposure around conception 0.91 (CI 0.66, 1.24.) based on data from 1,329 case and 12,141 control mothers, and 1,231 case and 11,383 control fathers. Our finding of a significantly increased risk of AML in the offspring with maternal exposure to pesticides during pregnancy is consistent with previous reports. We also found a slight increase in risk of ALL with paternal exposure around conception which appeared to be more evident in children diagnosed at the age of 5 years or more and those with T cell ALL which raises interesting questions on possible mechanisms.  相似文献   
995.
Turner syndrome is a rare genetic disorder, affecting approximately one in 2500 live-born female, due to total or partial absence of the X chromosome. Typical clinical features are short stature and premature ovarian failure and less constantly phenotypic particularities such as congenital malformations, acquired cardiovascular, otological (hearing impairment), autoimmune and metabolic pathologies. The phenotype is highly variable with slight or even normal phenotype. Several studies have shown that growth hormone treatment improves adult height. The possibility of pregnancies after oocyte donation highlights the high risk of these pregnancies requiring a careful follow-up, especially in terms of cardiovascular issues. Although the quality of life seems similar to the normal population, the presence of cardiovascular and otological diseases, and delayed feminisation are associated with an impaired quality of life. Early diagnosis and regular screening for potentials associated complications are essential in the medical follow-up of these patients. The recent publication of recommendations should lead to an optimization and harmonisation of the medical practices and follow-up from paediatric age to adulthood, a lowering morbidity and self-esteem improvement. The interest of ovarian cryopreservation at an early age in these patients is under investigation.  相似文献   
996.
997.
998.
Bubble-enhanced heating (BEH) can be exploited to increase heating efficiency in treatment of liver tumors with non-invasive high-intensity focused ultrasound (HIFU). The objectives of this study were: (i) to demonstrate the feasibility of increasing the heating efficiency of sonication exploiting BEH in pig liver in vivo using a clinical platform; (ii) to determine the acoustic threshold for such effects with real-time, motion-compensated magnetic resonance-guided thermometry; and (iii) to compare the heating patterns and thermal lesion characteristics resulting from continuous sonication and sonication including a burst pulse. The threshold acoustic power for generation of BEH in pig liver in vivo was determined using sonication of 0.5-s duration (“burst pulse”) under real-time magnetic resonance thermometry. In a second step, experimental sonication composed of a burst pulse followed by continuous sonication (14.5 s) was compared with conventional sonication (15 s) of identical energy (1.8 kJ). Modification of the heating pattern at the targeted region located at a liver depth between 20 and 25 mm required 600–800 acoustic watts. The experimental group exhibited near-spherical heating with 40% mean enhancement of the maximal temperature rise as compared with the conventional sonication group, a mean shift of 7 ± 3.3 mm toward the transducer and reduction of the post-focal temperature increase. Magnetic resonance thermometry can be exploited to control acoustic BEH in vivo in the liver. By use of experimental sonication, more efficient heating can be achieved while protecting tissues located beyond the focal point.  相似文献   
999.
Bensoussan L, Viton J-M, Schieppati M, Collado H, Milhe de Bovis V, Mesure S, Delarque A. Changes in postural control in hemiplegic patients after stroke performing a dual task.

Objective

To determine the effects of an attentional task on hemiplegic patients’ postural control performances.

Design

Retrospective study.

Setting

Department of physical and rehabilitation medicine at a university hospital.

Participants

Twenty-three hemiplegic patients and 23 healthy age- and sex-matched control subjects.

Interventions

Not applicable.

Main Outcome Measures

Sway area and sway path of the center of pressure were measured during 30 seconds in standing subjects and patients under 3 conditions: eyes open (EO), EO while performing a simple arithmetic task (EO-AT), and eyes closed (EC).

Results

In the hemiplegic patients, the body sway area increased significantly with EC (P<.001) and during the EO-AT task (P<.017) in comparison with EO. Sway area with EO-AT remained, however, significantly smaller than with EC (P<.014). In the healthy subjects, the body sway did not differ significantly between the EO-AT and EO tasks (P<.42). The increase observed in the sway area and path in the hemiplegic population during the EO-AT task correlated significantly with age.

Conclusions

The postural performances of hemiplegic patients decreased during both the arithmetic task and the EC task. The cognitive task had no effect on healthy subjects’ postural performances. This study is the first to show the combined effects of age and dual task on the postural performances of hemiplegic subjects.  相似文献   
1000.
It has been suggested that a high intake of dietary fibre helps regulate energy intake and satiety. The present study aimed to examine whether dietary fibre influenced the liking and wanting components of the food reward system, the metabolic state or subsequent intake. Five sessions involving 32 normal-weight subjects (16 men and 16 women, 30.6 ± 7.6 year) were held. The sessions differed in the composition of the bread eaten during breakfasts (dietary fibre content varied from 2.4 to 12.8 g/100 g). Several factors such as the palatability, weight, volume, energy content and macronutrient composition of the breakfasts were adjusted. Energy expenditure, the respiratory quotient (R), olfactory liking for four foods, wanting for six other foods, and hunger sensations were evaluated before and after the breakfast, as well as before a morning snack. The results showed no significant differences after ingestion of the various breads. Interestingly, R correlated with olfactory liking and with wanting, which highlights in an original manner the influence of the metabolic state on hedonic sensations for food. In conclusion, dietary fibre was found to have no effect on olfactory liking and wanting, and had no detectable effect on satiety sensations or on subsequent energy intake.  相似文献   
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