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51.
In patients with prostate cancer, a positive surgical margin is associated with an increased risk of cancer recurrence and poorer outcome, yet margin status cannot be determined during the surgery. An in vivo optical imaging probe that could identify the tumor margins during surgery could result in improved outcomes. The design of such a probe focuses on a highly specific targeting moiety and a near-infrared (NIR) fluorophore that is activated only when bound to the tumor. In this study, we successfully synthesized an activatable monoclonal antibody-fluorophore conjugate consisting of a humanized anti-Prostate-Specific Membrane Antigen (PSMA) antibody (J591) linked to an indocyanine green (ICG) derivative. Prior to binding to PSMA and cellular internalization, the conjugate yielded little light; however, after binding an 18-fold activation was observed permitting the specific detection of PSMA+ tumors up to 10 days after injection of a low dose (0.25 mg/kg) of the reagent. This agent demonstrates promise as a method to image the extent of prostate cancer in vivo and could assist with real-time resection of extracapsular extension of tumor and positive lymph nodes.  相似文献   
52.
The cytologic appearance of a carcinosarcoma (malignant ameloblastoma and fibrosarcoma) of the maxilla in a 63-year-old man is described. On his first admission the diagnosis of malignant ameloblastoma was made on biopsy. After five surgical excisions, radiotherapy and chemotherapy, the diagnosis was changed to carcinosarcoma because the stromal cells of the tumor had become malignant. Aspiration biopsy cytology of the tumor, with a cystic lesion found at the left suborbital area, revealed malignant epithelial cells, indicating malignant ameloblastoma. Imprint smears of both surgically resected and autopsy material showed two types of malignant neoplastic cells, of epithelial and mesenchymal origin.  相似文献   
53.
Neutral glycosphingolipids and gangliosides were extracted from pig cortical bone and cartilage. To ensure the completeness of extraction, the cortical bone was demineralized and reextracted. Globotriaosylceramide and globoside were noted to be present at high content in the cortical bone. It contained glucosylceramide, lactosylceramide, globotriaosylceramide and globoside as neutral glycosphingolipids at a ratio of 1:0.7:3.1:2.7. In articular cartilage, the ratio was 1:0.7:0.4:0.8. GM3 and GD3 were the major gangliosides in both these tissues. GM3, GM1, GD3, GD1 and GT1 were present at ratios of 1:0.9:0.9:0.1:0.1 in the cortical bone and 1:0:1.2:0.06:0.02 in the cartilage. Neutral glycosphingolipids could be extracted from the cortical bone without the need for demineralization, while most of the gangliosides were extracted after this treatment, implying the occurrence of interactions between gangliosides and minerals in the bone.  相似文献   
54.

Background

Associations between lifetime traumatic event (LTE) exposures and subsequent physical ill-health are well established but it has remained unclear whether these are explained by PTSD or other mental disorders. This study examined this question and investigated whether associations varied by type and number of LTEs, across physical condition outcomes, or across countries.

Methods

Cross-sectional, face-to-face household surveys of adults (18+) were conducted in 14 countries (n = 38, 051). The Composite International Diagnostic Interview assessed lifetime LTEs and DSM-IV mental disorders. Chronic physical conditions were ascertained by self-report of physician''s diagnosis and year of diagnosis or onset. Survival analyses estimated associations between the number and type of LTEs with the subsequent onset of 11 physical conditions, with and without adjustment for mental disorders.

Findings

A dose-response association was found between increasing number of LTEs and odds of any physical condition onset (OR 1.5 [95% CI: 1.4–1.5] for 1 LTE; 2.1 [2.0–2.3] for 5+ LTEs), independent of all mental disorders. Associations did not vary greatly by type of LTE (except for combat and other war experience), nor across countries. A history of 1 LTE was associated with 7/11 of the physical conditions (ORs 1.3 [1.2–1.5] to 1.7 [1.4–2.0]) and a history of 5+ LTEs was associated with 9/11 physical conditions (ORs 1.8 [1.3–2.4] to 3.6 [2.0–6.5]), the exceptions being cancer and stroke.

Conclusions

Traumatic events are associated with adverse downstream effects on physical health, independent of PTSD and other mental disorders. Although the associations are modest they have public health implications due to the high prevalence of traumatic events and the range of common physical conditions affected. The effects of traumatic stress are a concern for all medical professionals and researchers, not just mental health specialists.  相似文献   
55.
Synaptic dysfunction and neuronal death are responsible for cognitive and behavioral deficits in Alzheimer's disease (AD). It is well known that such neurological abnormalities are preceded by long‐term exposure of amyloid β‐peptide (Aβ) and/or hyperphosphorylated tau prior. In addition to the neurological deficit, astrocytes as a major glial cell type in the brain, significantly participate in the neuropathogenic mechanisms underlying synaptic modulation. Although astrocytes play a significant key role in modulating synaptic transmission, little is known on whether astrocyte dysfunction caused by such long‐term Aβ exposure affects synapse formation and function. Here, we show that synapse formation and synaptic transmission are attenuated in hippocampal‐naïve neurons co‐cultured with astrocytes that have previously experienced chronic Aβ1‐40 exposure. In this abnormal astrocytic condition, hippocampal neurons exhibit decrements of evoked excitatory post‐synaptic currents (EPSCs) and miniature EPSC frequency. Furthermore, size of readily releasable synaptic pools and number of excitatory synapses were also significantly decreased. Contrary to these negative effects, release probability at individual synapses was significantly increased in the same astrocytic condition. Taken together, our data indicate that lower synaptic transmission caused by astrocytes previously, and chronically, exposed to Aβ1–40 is attributable to a small number of synapses with higher release probability.

  相似文献   
56.
Spectrin repeat (SR)-containing proteins are important for regulation of integrity of biomembranes, not only the plasma membrane but also those of intracellular organelles, such as the Golgi, nucleus, endo/lysosomes, and synaptic vesicles. We identified a novel SR-containing protein, named GSRP-56 (Golgi-localized SR-containing protein-56), by a yeast two-hybrid method, using a member of the transient receptor potential channel family, TRPV2, as bait. GSRP-56 is an isoform derived from a giant SR-containing protein, Syne-1 (synaptic nuclear envelope protein-1, also referred to as Nesprin-1 or Enaptin), predicted to be produced by alternative splicing. Immunological analysis demonstrated that this isoform is a 56-kDa protein, which is localized predominantly in the Golgi apparatus in cardiomyocytes and C2C12 myoblasts/myotubes, and we found that two SR domains were required both for Golgi targeting and for interaction with TRPV2. Interestingly, overexpression of GSRP-56 resulted in a morphological change in the Golgi structure, characterized by its enlargement of cis-Golgi marker antibody-staining area, which would result partly from fragmentation of Golgi membranes. Our findings indicate that GSRP-56 is a novel, particularly small Golgi-localized member of the spectrin family, which possibly play a role in maintenance of the Golgi structure.  相似文献   
57.
Axotomy-induced neuronal death occurs in neonatal motoneurons, but not in adult rat. Here we demonstrated that during the course of postnatal development, nerve injury induced down-regulation of the glial cell line-derived neurotrophic factor (GDNF) receptor GFRalpha1 in axotomized hypoglossal motoneurons of rat are gradually converted to the adult up-regulation pattern of response. The compensatory expression of GFRalpha1 specifically in the injured motoneurons of neonates by adenovirus succeeded in rescuing the injured neurons without an application of growth factors. To the contrary, the nuclear antisense RNA for GFRalpha1 expression accelerates the axotomy-induced neuronal death in pups. These findings suggest that the receptor expression response after nerve injury is critical for the determination of injured motoneuron fate.  相似文献   
58.
Malignant mesothelioma (MM) is an asbestos-related malignancy characterized by rapid growth and poor prognosis. In our previous study, we have demonstrated that several cancer stem cell (CSC) markers correlated with CSC properties in MM cells. Among these markers, we focused on two: CD24, the common CSC marker, and CD26, the additional CSC marker. We further analyzed the CSC properties of CD24 and CD26-positve MM cells. We established RNAi-knockdown cells and found that these markers were significantly correlated with chemoresistance, proliferation, and invasion potentials in vitro. Interestingly, while Meso-1 cells expressed both CD24 and CD26, the presence of each of these two markers was correlated with different CSC property. In addition, downstream signaling of these markers was explored by microarray analysis, which revealed that their expressions were correlated with several cancer-related genes. Furthermore, phosphorylation of ERK by EGF stimulation was significantly affected by the expression of CD26, but not CD24. These results suggest that CD24 and CD26 differentially regulate the CSC potentials of MM and could be promising targets for CSC-oriented therapy.  相似文献   
59.

Aims

The mechanisms underlying magnesium (Mg) uptake by plant roots remain to be fully elucidated. In particular, there is little information about the effects of Mg deficiency on Mg uptake activity. A Mg uptake kinetic study is essential for better understanding the Mg uptake system.

Methods

We performed a Mg uptake tracer experiment in rice plants using 28?Mg.

Results

Mg uptake was mediated by high- and low-affinity transport systems. The K m value of the high-affinity transport system was approximately 70 μM under Mg-deficient conditions. The Mg uptake activity was promoted by Mg deficiency, which in turn fell to the basal level after 5- min of Mg resupply. The induced uptake rate was inhibited by ionophore treatment, suggesting that an energy-dependent uptake system is enhanced by Mg deficiency.

Conclusions

The Mg uptake changes rapidly with Mg conditions in rice, as revealed by a 28?Mg tracer experiment. This technique is expected to be applicable for Mg uptake analyses, particularly in mutants or other lines.
  相似文献   
60.
ABSTRACT

Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a “hypomanic state.” The median (interquartile range) YMRS score was 2.0 (0–5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09–4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15–5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients.  相似文献   
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