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991.
The aim of this study was to examine the influence of different fat diets on muscarinic acetylcholine receptor binding. Nineteen male Sprague–Dawley rats were divided into four groups and fed a diet of either high saturated fat, n-6 polyunsaturated fatty acid (PUFA), n-3 PUFA or low fat (control) for 8 weeks. Using quantitative autoradiography, [3H]pirenzepine binding to muscarinic M1/M4 receptors and [3H]AF-DX384 binding to M2/M4 receptors were measured throughout the brain in all four groups. The main findings were that compared to the low fat control group, M2/M4 receptor binding was significantly reduced in the dorsolateral, dorsomedial and ventromedial parts of the caudate putamen (61–64%, p < 0.05), anterior cingulate cortex (59%, p < 0.01), dentate gyrus and CA1–3 fields of the hippocampus (32–43%, p < 0.01) of rats on a high n-6 PUFA diet; however, no differences in M1/M4 receptor binding densities between the four groups were observed. These results suggest that a diet high in n-6 PUFA, but not of n-3 PUFAs or saturated fat, may selectively alter M2/M4 receptor-mediated signal transduction in the rat brain.  相似文献   
992.
993.
Niemann-Pick disease type C (NPC), a severe neurovisceral lysosomal disorder, is due to mutations on the NPC1 gene or, in a minority of families, the NPC2 gene. Few investigations have been devoted to the NPC2 protein, for which only 13 different disease-causing mutations (including three novel ones in this report) have been described. Among the currently known NPC2 mutant alleles, six resulted in a premature stop codon. Only five missense mutations, c.115G>A (p.V39M), c.140G>T (p.C47F), c.199T>C (p.S67P), c.278G>T (p.C93F), and (this report) c.295T>C (p.C99R) were identified. In the present study, we generated cDNA constructs harboring each of these missense mutations and, upon overexpression in human fibroblasts with a nonsense NPC2 mutation, characterized the mutated proteins by immunoblotting, immunocytofluorescence microscopy, and complementation. Mutation p.V39M, described in the homozygous state in two patients with an adult-onset neurological disease, resulted in the synthesis of apparently functional recombinant proteins correctly targeted to lysosomes. Although a mild functional impact could possibly be overlooked in our overexpression system, comparative studies with NPC1 mutants indicated that mild mutations might not necessarily affect localization of the protein or its quantity in the native state. Conversely, mutations p.C47F, p.C93R, p.C99R but also, less predictably, p.S67P, led to the synthesis of misfolded recombinant proteins that colocalized with an endoplasmic reticulum marker. The four latter proteins were normally secreted but were unable to correct cholesterol storage in NPC2(-/-) cells. Functional characterization of the mutant proteins showed an excellent genotype-phenotype correlation in the three cases for whom a clinical history was available.  相似文献   
994.
995.

Background

The importance of dendritic cells (DCs) in the initiation of the Th2-mediated inflammatory response to allergens is well known and more recently it has been proposed that DCs have a pivotal role in maintaining tolerance to allergens. The aim of this study was to investigate whether the success of sublingual immunotherapy (SLIT) in allergic asthma is mediated by the induction of changes of DCs functions.

Methods

Ten children with allergic asthma sensitive to house dust mite were studied before and after 12 months of SLIT. Immature DCs were derived from peripheral blood monocytes cultured for 6 days in presence of interleukin (IL)-4 and GM-CSF and stimulated with lipopolysaccharide for the last 24 hours to induce maturation.

Results

After 12 months of SLIT, mature DCs derived from SLIT-treated patients showed a statistically significant defect of CD86 up-regulation, an increase of IL-10, and a reduction of IL-12 production.

Conclusion

SLIT induces changes in DCs functions that might be responsible for an impairment of T cell activation or drive T cells towards a regulatory activity, thus restoring immune tolerance to allergens.  相似文献   
996.
Aim: Equipment (Pea Pod) offering new possibilities to assess infant body composition has recently become available and has already been used in several studies. In the Pea Pod, body density is converted to body composition using one of two models (‘Fomon’ or ‘Butte’) with different water content in fat‐free mass (hydration factor, HF). In healthy full‐term infants, we assessed HF and its biological variability in 12 newborns and calculated body composition using the two models at 1 and 12 weeks in 108 infants. Body weight and volume were assessed in Pea Pod, and body water was assessed using isotope dilution. Results: Hydration factor was 80.9% with low biological variability (0.8% of average HF). Body fat (%) was significantly lower at 1 and 12 weeks when calculated using the ‘Butte’ model than when using the ‘Fomon’ model. The difference was more pronounced at one than at 12 weeks. Conclusion: Our HF value agrees with that in the ‘Fomon’ model, its low biological variability can be reconciled with the statement that Pea Pod is accurate in newborns and ‘Fomon’ is the best available model for studies in Pea Pod.  相似文献   
997.
BACKGROUND: Although cervical cancer is clinically staged, surgery has long been considered the best means to assess extrapelvic disease and remains the gold standard for the detection of both intraperitoneal spread and small volume nodal metastases. The objective of this study was to determine short- and long-term outcomes for patients with locally advanced cervical cancer who underwent pretherapeutic laparoscopic staging. METHODS: From 1997 to 2004, 184 patients with stages IB2-IVA cervical cancer underwent pretherapeutic laparoscopic staging procedure including transperitoneal abdomino-pelvic exploration and extraperitoneal bilateral infrarenal paraaortic lymph node dissection. Patients were then treated with definitive radiotherapy tailored according to the staging results. RESULTS: The median age and BMI were respectively 45.8 years old and 27.1 kg/m2. Most lesions were squamous (n=172) and clinical stage was evenly distributed. Median operative time was 155 min with an average of 20.8 lymph nodes removed. Postoperative hospital stay averaged 1.4 days. Major complications included 1 intraoperative ureteral injury and 1 postoperative bowel obstruction from an umbilical trocar site hernia. The final pathology revealed that 44 patients (24.3%) had metastatic disease within paraaortic lymph nodes. With a median follow-up of 26.8 months (average 32.9), 67 patients (36.4%) had recurrent disease. Overall 5-year survival rate was 58.3%. Successful resection of positive lymph node correlated with a survival advantage. CONCLUSIONS: Pretherapeutic laparoscopic assessment of patients with locally advanced cervical cancer offers valuable information for individualized treatment planning with minimal morbidity. This appears to be a therapeutic effect with resection of positive nodes followed by a tailored chemoradiation therapy.  相似文献   
998.
999.
PurposeHaploinsufficiency of PSMD12 has been reported in individuals with neurodevelopmental phenotypes, including developmental delay/intellectual disability (DD/ID), facial dysmorphism, and congenital malformations, defined as Stankiewicz-Isidor syndrome (STISS). Investigations showed that pathogenic variants in PSMD12 perturb intracellular protein homeostasis. Our objective was to further explore the clinical and molecular phenotypic spectrum of STISS.MethodsWe report 24 additional unrelated patients with STISS with various truncating single nucleotide variants or copy-number variant deletions involving PSMD12. We explore disease etiology by assessing patient cells and CRISPR/Cas9-engineered cell clones for various cellular pathways and inflammatory status.ResultsThe expressivity of most clinical features in STISS is highly variable. In addition to previously reported DD/ID, speech delay, cardiac and renal anomalies, we also confirmed preaxial hand abnormalities as a feature of this syndrome. Of note, 2 patients also showed chilblains resembling signs observed in interferonopathy. Remarkably, our data show that STISS patient cells exhibit a profound remodeling of the mTORC1 and mitophagy pathways with an induction of type I interferon-stimulated genes.ConclusionWe refine the phenotype of STISS and show that it can be clinically recognizable and biochemically diagnosed by a type I interferon gene signature.  相似文献   
1000.
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.  相似文献   
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