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991.

BACKGROUND:

There are no reports on the long-term follow-up of patients with swine-origin influenza A virus infection that progressed to acute respiratory distress syndrome.

METHODS:

Four patients were prospectively followed up with pulmonary function tests and high-resolution computed tomography for six months after admission to an intensive care unit.

RESULTS:

Pulmonary function test results assessed two months after admission to the intensive care unit showed reduced forced vital capacity in all patients and low diffusion capacity for carbon monoxide in two patients. At six months, pulmonary function test results were available for three patients. Two patients continued to have a restrictive pattern, and none of the patients presented with abnormal diffusion capacity for carbon monoxide. All of them had a diffuse ground-glass pattern on high-resolution computed tomography that improved after six months.

CONCLUSIONS:

Despite the marked severity of lung disease at admission, patients with acute respiratory distress syndrome caused by swine-origin influenza A virus infection presented a late but substantial recovery over six months of follow-up.  相似文献   
992.
Obsessive Compulsive Disorder (OCD) involves failures in two main inhibitory processes, namely cognitive (obsessions) and behavioral (compulsions). Recent research has supported two cortical-subcortical pathways on OCD pathogenesis: (a) the frontostriatal loop (dorsolateral-caudate-striatum-thalamus) responsible for impairments of behavioral inhibition; (b) the orbitofrontal loop (orbitofrontal, medial prefrontal and cingulate) responsible for impairments with cognitive inhibitory processes. These failures in both cognitive and motor inhibitory systems may mediate several neuropsychological deficits in these patients, namely memory, attention, planning and decision making. But are those deficits related to specific hemispheric effects, namely functional imbalance between hemispheres? In this article we hypothesize that: (1) OCD patients have an inter-hemispheric functional imbalance, probably due to inadequate filtering at the thalamic level; (2) the restoration of inter-hemispheric balance, will be correlative to symptomatic improvement.  相似文献   
993.
Salivary glands of Dermatobia hominis (L., Jr.) (Diptera: Oestridae) larvae were studied under light and electron microscopy. The salivary glands of second (L2) and third instars (L3) are similar and consist of pairs of translucent tubules. The individual efferent ducts unite to form a single deferent duct, which inserts dorsally into the cephalopharingeal skeleton. Each gland has a monolayer of epithelial cells surrounded by basement membrane and connective tissue. The cellular plasma membrane is enfolded at its base, forming a labyrinthine area. The cell surface is linked to the basement membrane (BM) by hemidesmosomes and to adjacent cells by septet junctions and desmosomes. Irregular channels with several vesicles occur between the cytoplasm and BM. Golgi complex, rough and smooth endoplasmic reticulum, ribosome, lysosomes, multivesicular bodies, and myelin figures are usually present in the cells. The nucleus is large, with diffuse chromatin. The connective tissue circling the BM contains collagen fibrils, muscle fibers and tracheal tubes. Lined cuticle encloses the efferent and deferent ductal cells, which have few, widely dispersed mitochondria, free ribosomes, microtubules, and a large nucleus with diffuse chromatin.  相似文献   
994.
995.
In early-onset myasthenia gravis, the thymus contains lymph node-type infiltrates with frequent acetylcholine receptor (AChR)-specific germinal centers. Our recent evidence/two-step hypothesis implicates hyperplastic medullary thymic epithelial cells (expressing isolated AChR subunits) in provoking infiltration and thymic myoid cells (with intact AChR) in germinal center formation. To test this, we screened for complement attack in a wide range of typical generalized myasthenia patients. Regardless of the exact serology, thymi with sizeable infiltrates unexpectedly showed patchy up-regulation of both C5a receptor and terminal complement regulator CD59 on hyperplastic epithelial cells. These latter also showed deposits of activated C3b complement component, which appeared even heavier on infiltrating B cells, macrophages, and especially follicular dendritic cells. Myoid cells appeared particularly vulnerable to complement; few expressed the early complement regulators CD55, CD46, or CR1, and none were detectably CD59(+). Indeed, when exposed to infiltrates, and especially to germinal centers, myoid cells frequently labeled for C1q, C3b (25 to 48%), or even the terminal C9, with some showing obvious damage. This early/persistent complement attack on both epithelial and myoid cells strongly supports our hypothesis, especially implicating exposed myoid cells in germinal center formation/autoantibody diversification. Remarkably, the similar changes place many apparent AChR-seronegative patients in the same spectrum as the AChR-seropositive patients.  相似文献   
996.
Wound healing studies are intricate, mainly because of the multifaceted nature of the wound environment and the complexity of the healing process, which integrates a variety of cells and repair phases, including inflammation, proliferation, reepithelialization and remodelling. There are a variety of possible preclinical models, such as in mice, rabbits and pigs, which can be used to mimic acute or impaired for example, diabetic and nutrition‐related wounds. These can be induced by many different techniques, with excision or incision being the most common. After determining a suitable model for a study, investigators need to select appropriate and reproducible methods that will allow the monitoring of the wound progression over time. The assessment can be performed by non‐invasive protocols such as wound tracing, photographic documentation (including image analysis), biophysical techniques and/or by invasive protocols that will require wound biopsies. In this article, we provide an overview of some of the most often needed and used: (a) preclinical/animal models including incisional, excisional, burn and impaired wounds; (b) methods to evaluate the healing progression such as wound healing rate, wound analysis by image, biophysical assessment, histopathological, immunological and biochemical assays. The aim is to help researchers during the design and execution of their wound healing studies.  相似文献   
997.
Plant biodiversity is a source of potential natural products for the treatment of many diseases. One of the ways of discovering new drugs is through the cytotoxic screening of extract libraries. The present study evaluated 196 extracts prepared by maceration of Brazilian Atlantic Forest trees with organic solvents and distilled water for cytotoxic and antimetastatic activity. The MTT assay was used to screen the extract activity in MCF‐7, HepG2 and B16F10 cancer cells. The highest cytotoxic extract had antimetastatic activity, as determined in in vitro assays and melanoma murine model. The organic extract of the leaves of Athenaea velutina (EAv) significantly inhibited migration, adhesion, invasion and cell colony formation in B16F10 cells. The phenolic compounds and flavonoids in EAv were identified for the first time, using flow injection with electrospray negative ionization‐ion trap tandem mass spectrometry analysis (FIA‐ESI‐IT‐MSn). EAv markedly suppressed the development of pulmonary melanomas following the intravenous injection of melanoma cells to C57BL/6 mice. Stereological analysis of the spleen cross‐sections showed enlargement of the red pulp area after EAv treatment, which indicated the activation of the haematopoietic system. The treatment of melanoma‐bearing mice with EAv did not result in liver damage. In conclusion, these findings suggest that A velutina is a source of natural products with potent antimetastatic activity.  相似文献   
998.
Next‐generation sequencing technology aided the identification of the underlying genetic cause in a female newborn with a severe neuromuscular disorder. The patient presented generalized hypotonia, congenital bone fractures, lack of spontaneous movements and poor respiratory effort. She died within the first days of life. Karyotyping and screening for several genes related with neuromuscular diseases all tested negative. A male sibling was subsequently born with the same clinical presentation. Whole‐exome sequencing was performed with variant filtering assuming a recessive disease model. Analysis focused on genes known to be related firstly with congenital myopathies, extended to muscle diseases and finally to other neuromuscular disorders. No disease‐causing variants were identified. A similar disorder was described in patients with recessive variants in two genes: TRIP4 (three families) and ASCC1 (one family), both encoding subunits of the nuclear activating signal cointegrator 1 (ASC‐1) complex. Our patient was also found to have a homozygous frameshift variant (c.157dupG, p.Glu53Glyfs*19) in ASCC1 , thereby representing the second known case. This confirms ASCC1 involvement in a severe neuromuscular disease lying within the spinal muscular atrophy or primary muscle disease spectra.  相似文献   
999.
Loss of function mutations within the vesicular trafficking protein Ras analogy in brain 39B (RAB39B) are associated with rare X‐linked Parkinson’s disease (PD). Physiologically, RAB39B is localized to Golgi vesicles and recycling endosomes and is required for glutamatergic receptor maturation but also for alpha‐Synuclein (aSyn) homeostasis and the inhibition of its aggregation. Despite evidence linking RAB39B to neurodegeneration, the involvement of the protein in idiopathic neurodegenerative diseases remains undetermined. Here, analysis of the spatial distribution and expression of RAB39B was conducted in post‐mortem human brain tissue from cases of dementia with Lewy bodies (DLB, n = 10), Alzheimer’s disease (AD, n = 12) and controls (n = 12). Assessment of cortical RAB39B immunoreactivity using tissue microarrays revealed an overall reduction in the area of RAB39B positive gray matter in DLB cases when compared to controls and AD cases. Strikingly, RAB39B co‐localized with beta‐amyloid (Aβ) plaques in all cases examined and was additionally present in a subpopulation of Lewy bodies (LBs) in DLB. Biochemical measures of total RAB39B levels within the temporal cortex were unchanged between DLB, AD and controls. However, upon subcellular fractionation, a reduction of RAB39B in the cytoplasmic pool was found in DLB cases, alongside an increase of phosphorylated aSyn and Aβ in whole tissue lysates. The reduction of cytoplasmic RAB39B is consistent with an impaired reserve capacity for RAB39B‐associated functions, which in turn may facilitate LB aggregation and synaptic impairment. Collectively, our data support the involvement of RAB39B in the pathogenesis of DLB and the co‐aggregation of RAB39B with Aβ in plaques suggests that age‐associated cerebral Aβ pathology may be contributory to the loss of RAB39B. Thus RAB39B, its associated functional pathways and its entrapment in aggregates may be considered as future targets for therapeutic interventions to impede the overall pathological burden and cellular dysfunction in Lewy body diseases.  相似文献   
1000.
Global warming can stimulate mosquitoes to proliferate and the consumption of repellents and insecticides. These formulations can have N,N-diethyl-m-toluamide (DEET) and permethrin, which were reported in water bodies, requiring sensitive methods for quantification. We propose changing the dispersive liquid-liquid microextraction (DLLME), a green extraction technique, by inverting the sequence of injection of the extractant-dispersant solvents to allow better interaction with samples, aiming to improve the reproducibility of analytical results. In the inverse dispersive liquid-liquid microextraction (I-DLLME), samples of deionized water or freshwater enriched with DEET and permethrin isomers (trans = PERM-1) and (cis = PERM-2) were injected over the extractant-dispersant solvents using a micro-syringe. Both DLLME and I-DLLME were optimized using a factorial design and multi-response optimization (desirability function) to establish the condition that provides higher enrichment factor (EF) and reproducibility, denoted by lower relative standard deviations (RSD). Preconcentrated samples were analyzed using a High-Performance Liquid Chromatography with Diode Array Detector (HPLC-DAD) method. Under the optimum I-DLLME-HPLC-DAD condition (50 μL of chloroform as dispersant, 600 μL of acetonitrile as extractant, 0.007 mol/L of NaCl, and pH = 3), the EF for DEET, PERM-1 and PERM-2 were respectively 67, 170 and 179 with considerable gains in reproducibility (RSDs≤12%, n = 6). Quantification limits for DEET, PERM-1 and PERM-2 for deionized water and freshwater were respectively 50.0, 4.42 and 2.88 μg/L, and 33.06, 12.62 and 6.45 μg/L, without matrix effect. The apparent recovery for freshwater varied between 93% and 103% (RSDs 2.3–12%). The I-DLLME-HPLC-DAD method scored 0.61, considering the 12 principles of green analytical chemistry from a unified 0–1 scale.  相似文献   
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