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991.
Here, we report a juvenile (18-year-old male) case of epilepsy-associated, isocitrate dehydrogenase wild-type/histone 3 wild-type diffuse glioma with a rare BRAF mutation and a focal atypical feature resembling diffuse astrocytoma. The patient presented with refractory temporal lobe epilepsy. Subsequently, magnetic resonance imaging revealed a hyperintense lesion in the right temporal lobe on fluid attenuated inversion recovery images. The patient underwent right lateral temporal lobectomy and amygdalohippocampectomy. Histopathologically, the tumor showed isomorphic, diffuse, infiltrative proliferation of glial tumor cells and intense CD34 immunoreactivity. The tumor cells were immunonegative for isocitrate dehydrogenase 1 (IDH1) R132H and BRAF V600E. Notably, the tumor cells showed the lack of nuclear staining for α-thalassemia/mental retardation syndrome, X-linked (ATRX). In addition, the Ki-67 labeling index, using a monoclonal antibody MIB-1, was elevated focally at tumor cells with p53 immunoreactivity. Molecular analyses identified a BRAFA598T mutation, the first case reported in a glioma. BRAFA598T is predicted to result in loss of kinase action; however, inactive mutants can stimulate mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) signaling through CRAF activation. Thus, according to the recent update of the consortium to inform molecular and practical approaches to central nervous system tumor taxonomy (cIMPACT-NOW update 4), our case is also compatible with diffuse glioma with the mitogen-activated protein kinase (MAPK) pathway alteration. Thorough immunohistochemical and molecular studies are necessary for diagnosis of epilepsy-associated, diffuse gliomas. Partial resemblance in histopathological and molecular genetic features to diffuse astrocytoma also calls for attention.  相似文献   
992.
Age and sex dependent differences in the clinical reference values for erythrocyte count (RBC), hemoglobin quantity (Hb), hematocrit (Ht) and other erythrocyte parameters including MCV (mean corpuscular volume), MCH (mean corpuscular hemoglobin), MCHC (mean corpuscular hemoglobin concentration) and RDW (red cell distribution width), were calculated by the iterative truncation method with correction (Usui's method) using the results from tests on 6,300 patients' specimens obtained at Kyoto University Hospital. For RBC, Hb and Ht, the data obtained from the individuals below 13 years old showed the normal or sometimes log-normal distribution, but adjustment by the Xn-type variable transformation was often necessary to obtain the normal distribution for the data taken from the populations containing individuals over the age of 14. For the clinical reference values of RBC, Hb and Ht, no sex difference was observed below the age of 12. The values for males were significantly higher than those of females in the age range 13-79, and the values showed no significant sex-dependent difference at ages above 80. In females, age-dependent change of values for RBC, Hb and Ht was less prominent than in males; especially the upper limit values for females were very stable for all ages. MCV and MCH gradually increased with age both in males and females, and the MCHC remained constant in all age populations of male and female. The reference value for RDW was generated by the percentile method instead of the iterative truncation method because of the strong deviation in the distribution pattern, and the RDW values showed a gradual increase with age in both males and females.  相似文献   
993.
A case of malignant mixed mullerian tumor of the ovary in a 57 year old woman is reported along with the results of an immunohistochemical study. The tumor, measuring 16·10·9cm, was composed predominantly of adenocarcinoma with a smaller amount of anaplastic carcinoma as an epithelial component and chondrosarcoma, liposarcoma, fibrosarcoma and rhabdomyoblasts as mesenchymal elements. Immunohistochemistry using paraffin sections demonstrated cytokeratin (CK) and epithelial membrane antigen (EMA), generally regarded as epithelial markers, not only in the epithelial component but also in chondrosarcoma cells. Vimentin and desmin, generally regarded as mesenchymal markers, were exhibited partly in carcinoma cells as well as in mesenchymal elements. Positive staining for S 100 protein was obtained not only in chondrosarcoma and liposarcoma cells, but also partly in adenocarcinoma cells. This intricate immunohistochemical picture reflected the histologic findings. It is noteworthy that both carcinoma cells and chondrosarcoma cells demonstrated simultaneous expression of CK, EMA, vimentin, desmin and S 100 protein. This somewhat unusual antigen expression by tumor cells may indicate a change in the nature of tumor cells due to microenvironmental factors. Acta Pathol Jpn 40: 845 850, 1990.  相似文献   
994.
Of purinergic receptors, P2X7 receptor (P2X7R, defined as a full‐length receptor) has unique characteristics, and its activation leads to ion channel activity and pore formation, causing cell death. Previously, we demonstrated that P2X7R expressed by nonstimulated astrocyte cultures obtained from SJL‐strain mice exhibits constitutive activation, implying its role in maintenance of cellular homeostasis. To obtain novel insights into its physiological roles, we examined whether constitutive activation of P2X7R is regulated by expression of its splice variants in such resting astrocytes, and whether their distinct expression profiles in different mouse strains affect activation levels of astrocytic P2X7Rs. In SJL‐ and ddY‐mouse astrocytes, spontaneous YO‐PRO‐1 uptake, an indicator of pore activity of P2X7R, was detected, but the uptake by the formers was significantly greater than that by the latter. Between the two mouse strains, there was a difference in their sensitivity of YO‐PRO‐1 uptake to antagonists, but not in the expression levels and sequences of P2X7R and pannexin‐1. Regarding expression of splice variants of P2X7R, expression of P2X7R variant‐3 (P2X7R‐v3) and ‐4 (P2X7R‐v4), but not variant‐2 and ‐k, was lower in SJL‐mouse astrocytes than in ddY‐mouse ones. On transfection of P2X7R‐v3 and ‐v4 into SJL‐mouse astrocytes, the pore activity was attenuated as in the case of the HEK293T cell‐expression system. These findings demonstrate that basal activity of P2X7R expressed by resting astrocytes is negatively regulated by P2X7R‐v3 and ‐v4, and that their distinct expression profiles result in the different activation levels of astrocytic P2X7Rs in different mouse strains. GLIA 2014;62:440–451  相似文献   
995.
The present functional magnetic resonance imaging (fMRI) study investigates the neural correlates of reachability judgements. In a block design experiment, 14 healthy participants judged whether a visual target presented at different distances in a virtual environment display was reachable or not with the right hand. In two control tasks, they judged the colour or the relative position of the visual target according to flankers. Contrasting the activations registered in the reachability judgement task and in the control tasks, we found activations in the frontal structures, and in the bilateral inferior and superior parietal lobe, including the precuneus, and the bilateral cerebellum. This fronto‐parietal network including the cerebellum overlaps with the brain network usually activated during actual motor production and motor imagery. In a following event‐related design experiment, we contrasted brain activations when targets were rated as ‘reachable’ with those when they were rated as ‘unreachable’. We found activations in the left premotor cortex, the bilateral frontal structures, and the left middle temporal gyrus. At a lower threshold, we also found activations in the left motor cortex, and in the bilateral cerebellum. Given that reaction time increased with target distance in reachable space, we performed a subsequent parametric analysis that revealed a related increase of activity in the fronto‐parietal network including the cerebellum. Unreachable targets did not show similar activation, and particularly in regions associated to motor production and motor imagery. Taken together, these results suggest that dynamical motor representations used to determine what is reachable are also part of the perceptual process leading to the distinct representation of peripersonal and extrapersonal spaces.  相似文献   
996.
Spatacsin (SPG11) is a major mutated gene in autosomal recessive spastic paraplegia with thin corpus callosum (ARHSP‐TCC) and is responsible for juvenile Parkinsonism. To elucidate the role of spatacsin in the pathogenesis of α‐synucleinopathies, an immunohistochemical investigation was performed on the brain of patients with Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) using anti‐spatacsin antibody. In PD, Lewy bodies (LBs) in the brain stem were positive for spatacsin. These LBs showed intense staining in their peripheral portions and occasionally in the central cores. Lewy neurites were also spatacsin‐positive. In DLB, cortical LBs were immunolabeled by spatacsin. In MSA, glial cytoplasmic inclusions (GCI) and a small fraction of neuronal cytoplasmic inclusions (NCI) were positive for spatacsin. The widespread accumulation of spatacsin observed in pathologic α‐synuclein‐containing inclusions suggests that spatacsin may be involved in the pathogenesis of α‐synucleinopathies.  相似文献   
997.
998.
Please cite this paper as: Heparanase activation induces epidermal hyperplasia, angiogenesis, lymphangiogenesis and wrinkles. Experimental Dermatology 2010; 19 : 965–972. Abstract: To clarify the difference between cutaneous responses to single and repeated barrier disruption, changes of epidermal gene expression were examined by using RT‐PCR. In repeatedly barrier‐disrupted skin, heparanase was specifically up‐regulated in epidermis. In addition, there was a marked decrease in heparan sulfate (HS) chains of perlecan in basement membrane at the dermal–epidermal junction (DEJ) compared with singly disrupted skin. HS chains form a reservoir for heparan sulfate‐binding growth factors. In repeatedly barrier‐disrupted skin, expression of vascular endothelial growth factor‐A (VEGF‐A), an angiogenic factor, was induced in epidermis, whereas thrombospondin‐1 (TSP‐1), an angiogenesis inhibitor, was down‐regulated, and concomitantly blood vessels were elongated and enlarged in dermis. Expression of VEGF‐C, a lymphangiogenesis factor, was augmented in epidermis of repeatedly barrier‐disrupted skin, concomitantly with an increase in the number and size of lymphatic vessels. Topical application of a synthetic heparanase inhibitor, 1‐[4‐(1H‐benzoimidazol‐2‐yl)phenyl]‐3‐[4‐(1H‐benzoimidazol‐2‐yl)phenyl]urea, to skin after barrier disruption significantly suppressed wrinkle formation, degradation of HS chains in the basement membrane, epidermal hyperplasia and the changes of blood and lymphatic vessels. These results suggest that chronic barrier disruption activates heparanase and induces gene expression changes, leading to increased growth factor interaction between epidermis and dermis, and facilitating various cutaneous changes, including wrinkle formation.  相似文献   
999.
We report a case of preeclampsia associated with hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome and concomitant nonbiliary acute pancreatitis and cholecystitis in the first postpartum day. A thorough investigation ruled out known etiologies of both pancreatitis and cholecystitis. Following conservative treatment, the patient's HELLP syndrome, pancreatitis, and cholecystitis resolved on the third postpartum day. Preeclampsia is associated with microvascular abnormalities that may involve the splanchnic circulation. These abnormalities may cause not only HELLP syndrome but also pancreatitis and cholecystitis. Recognizing that ischemia can damage not only the liver but also the pancreas and gallbladder, could result in improvements in the diagnosis and management of pancreatitis in patients with preeclampsia.  相似文献   
1000.
A 56-year-old man presented with a painless mass in the left scrotum. The mass was first noticed when he was a junior high school student,and it had been left for about 40 years. The intrascrotal tumor of 7 cm in diameter was elastic soft and smooth. The serum levels of α -fetoprotein, β -human chorionic gonadotropin and lactate dehydrogenase were within each individual normal range. He was diagnosed as having a left testicular tumor (cT1N0M0) and underwent left high orchiectomy. Histopathological diagnosis was mature teratoma without any malignant germ cell components. No evidence of recurrence has been observed for 4 years after the operation.  相似文献   
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