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71.
Elimination of granule cells (GCs) in the olfactory bulb (OB) is not a continual event but is promoted during a short time window in the postprandial period, typically with postprandial sleep. However, the neuronal mechanisms for the enhanced GC elimination during the postprandial period are not understood. Here, we addressed the question of whether top‐down inputs of centrifugal axons from the olfactory cortex (OC) during the postprandial period are involved in the enhanced GC elimination in the OB. Electrical stimulation of centrifugal axons from the OC of anesthetized mice increased GC apoptosis. Furthermore, pharmacological suppression of top‐down inputs from the OC to the OB during the postprandial period of freely behaving mice by γ‐aminobutyric acid (GABA)A receptor agonist injection in the OC significantly decreased GC apoptosis. Remarkable apoptotic GC elimination in the sensory‐deprived OB was also suppressed by pharmacological blockade of top‐down inputs. These results indicate that top‐down inputs from the OC to the OB during the postprandial period are the crucial signal promoting GC elimination, and suggest that the life and death decision of GCs in the OB is determined by the interplay between bottom‐up sensory inputs from the external world and top‐down inputs from the OC.  相似文献   
72.
We report three presenile patients who were initially suspected of having Alzheimer's disease (AD) or being in the prodromal stage of AD, regardless of visuoperceptual dysfunctions in daily living, because they lacked the core features and prodromal non‐motor symptoms of dementia with Lewy bodies. Subsequently, progression to dementia with Lewy bodies was suspected based on neuropsychological and neuroimaging findings; additionally, one of the three patients suffered from visual hallucinations. Neuropsychological examinations such as subjective contours, cube copying and block design in the Wechsler Adult Intelligence Scale‐III revealed visuoperceptual dysfunction in all three patients even when other cognitive functions were rather preserved. Brain magnetic resonance imaging revealed no significant brain atrophy, including in the parieto‐occipital area and the hippocampus, while brain 18F‐fluorodeoxyglucose positron emission tomography demonstrated right dominant metabolic reductions in the occipital lobe, including the primary visual cortex, in all three patients. We suggest the possibility of progression to dementia with Lewy bodies, but not AD or posterior cortical atrophy. Regardless of the presence of core features and prodromal non‐motor symptoms, this progression is suggested when there are difficulties only in higher‐level visual processing such as subjective contours and block design in the Wechsler Adult Intelligence Scale‐III, no significant atrophy of the parieto‐occipital area and hippocampus on brain magnetic resonance imaging, and hypometabolism in the occipital lobe including the primary visual cortex on brain 18F‐fluorodeoxyglucose positron emission tomography.  相似文献   
73.
We report on 2 patients with acute leukemia who had an 11q23 chromosomal aberration as an additional change after treatment with etoposide and mitoxantrone, agents that affect topoisomerase II (Topo II). One patient with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (L2) received chemotherapy, including 1,000 mg of etoposide and 75 mg of mitoxantrone. She relapsed 10 months later. Analysis at time of relapse showed a chromosomal aberration of del(11)(q23) as an additional cytogenetic change. The other patient was diagnosed with acute monoblastic leukemia (M5a) and received two autologous peripheral blood stem-cell transplantations. Her cumulative doses of etoposide and mitoxantrone were 6,000 mg and 42 mg, respectively. She also relapsed, and analysis at that time revealed del(11)(q23) as an additional chromosomal aberration. The mixed lineage leukemia/(myeloid-lymphoid leukemia (MLL) gene was not rearranged in either case, making these cases distinct from previously described therapy-related leukemias caused by Topo II Inhibitors. Based on these two cases, it may be that Topo II inhibitors can cause clonal evolution affecting chromosome band 11q23. © 1996 Wiley-Liss, Inc.  相似文献   
74.
A 40-year-old man presented at our hospital with anaemia that had been undiagnosed for 2 years. Blood tests, endoscopy, and contrast-enhanced computed tomography were performed, but a definitive diagnosis could not be made. A subsequent bone marrow biopsy revealed basophilic stippling in transformed red blood cells, which led to a differential diagnosis of lead poisoning. Additional tests revealed elevated levels of lead in the blood. Basophilic stippling is generally found on a peripheral blood smear in lead poisoning patients; however, in this case, basophilic stippling was found only on the bone marrow smear and not in the blood smear. Even if basophilic stippling is not found in the peripheral blood, lead poisoning cannot be excluded.  相似文献   
75.
The highly polysialylated form of neural cell adhesion molecule (PSA-NCAM) is important for neurite outgrowth. With this molecule as a marker of plastic change in neurons, we investigated its temporal expression in rat brain after transient middle cerebral artery (MCA) occlusion. In sham-control brain, only subependymal neurons showed a positive immunoreactivity for PSA-NCAM. After 90 min of transient MCA occlusion, neurons in the piriform cortex began to be positively stained at 1 h, while neurons in the cortex and caudate of the MCA territory became positive after 8 h. The stainings persisted for 1 and 3 days after reperfusion. The present results indicate that neurons in the cerebral cortex and caudate have the capability of plastic change in the adult brain, and that those in the piriform cortex rapidly undergo plastic change probably in response to transneuronal injury.  相似文献   
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78.
We report a case of retroperitoneal tumor which turned out to be liposarcoma by the histological evaluation of its recurrent tumor, although the initial tumor was diagnosed as malignant fibrous histiocytoma (MFH). A retroperitoneal tumor in a 62-year-old man was removed and pathologically diagnosed as MFH. Five years after the initial surgery, computed tomography (CT) demonstrated a recurrent tumor near the spleen. The tumor was resected together with the spleen, tail of pancreas, and connective tissue due to adhesion and diagnosed as well-differentiated liposarcoma with sclerosing component. Generally dedifferentiated liposarcoma is difficult to distinguish from MFH and the presence of a well-differentiated liposarcoma component in the adjacent adipose tissue leads to the diagnosis of dedifferentiated liposarcoma. The clinical course of the present case indicated that the initial tumor was dedifferentiated liposarcoma and the recurrent tumor developed from the surrounding well-differentiated liposarcoma.  相似文献   
79.
Purpose Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical significance of Aurora-A status. Experimental Design A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical staining was used to detect Aurora-A expression. Results Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7, and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%, and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A expression was an independent and significant factor to predict a poor prognosis. Conclusions Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative activity in NSCLC.  相似文献   
80.
Three flavonoids, quercetin 3- O-glucoside-2'-gallate (QGG), quercetin 3- O-rhamnoside-2'-gallate (QRG) and kaempferol 3- O-glucoside-2'-gallate (KGG) were isolated from Japanese Polygonum species. The effect of these flavonoids on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of cytochrome c. The tyrosyl or serine/threonine phosphorylation of neutrophil proteins and the translocation of p4(phox) and p67(phox) to the cell membrane were detected using specific monoclonal antibodies. The flavonoids used in this experiment significantly suppressed stimulus-induced superoxide generation in a concentration-dependent manner. FMLP-induced tyrosyl phosphorylation or PMA-induced serine/threonine phosphorylation and the translocation of the cytosolic proteins p47(phox) and p67(phox) to the cell membrane were suppressed in parallel to the suppression of the stimulus-induced superoxide generation.  相似文献   
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