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81.
ABSTRACT

Background: Intracranial vertebral artery dissection (VAD) and moyamoya disease (MMD) are rare cerebrovascular diseases, both of which have an ethnic predominance in the East Asian population. Disruption of the internal elastic lamina and subsequent rupture of the medial layer result in intracranial VAD. MMD is a chronic occlusive cerebrovascular disease of unknown etiology, in which the medial layer and internal elastic lamina of the intracranial arteries are significantly compromised. Recent genetic studies found ring finger protein 213 (RNF213) to be an important susceptibility gene for MMD in East Asian patients, but the association between VAD and RNF213 has not been investigated. .

Methods: We investigated polymorphism of the RNF213 gene (c.14576G>A) in genomic DNA of 24 patients with intracranial VAD in comparison with 58 patients with definitive MMD and 48 healthy controls.

Results: Although RNF213 gene polymorphism (c.14576G>A) was evident in 69% of the MMD patients (40/58), none of the patients with intracranial VAD had this characteristic polymorphism (0/24, p < 0.001). The incidence of RNF213 c.14576G>A polymorphism was 4.2% in healthy controls (2/48). After adjustment by age and sex, the incidence of RNF213 c.14576G>A was significantly lower in intracranial VAD patients (p = 0.021) than that in MMD patients.

Conclusions: In contrast to MMD patients, the prevalence of RNF213 c.14576G>A polymorphism was significantly lower in patients with intracranial VAD. The RNF213 gene polymorphism may preferentially affect the cerebrovascular lesion in the anterior circulation, which is originated from the primitive internal carotid arteries. The genetic background underlying intracranial VAD should be elucidated in future studies.

Abbreviations: VAD: vertebral artery dissection; MMD: moyamoya disease; RNF213: ring finger protein 213; CAD: carotid artery dissection  相似文献   
82.
Journal of Clinical Monitoring and Computing - Balloon test occlusion (BTO) is a useful examination for evaluating ischemic tolerance to internal carotid artery (ICA) occlusion. The aim of this...  相似文献   
83.
84.
BACKGROUND: Despite much concern about adult obesity among Pacific Islanders, childhood obesity has seldom been investigated. AIM: Based on the anthropometry of Tongan children aged 5-19 years, this study aims to elucidate age and sex differences in obesity prevalence calculated from BMI and its relation to body fat estimated by skinfold thicknesses. SUBJECTS AND METHODS: 895 students, aged 5-19 years, in the most modernized island and a remote island, were measured for stature, body weight, circumferences at waist, hip and mid-upper arm, and skinfold thicknesses at biceps, triceps and subscapular. The prevalence of overweight and obesity was calculated using the reference data of the International Obesity Task Force (IOTF) and the Centers for Disease Control and Prevention (CDC). RESULTS: The prevalence of obesity of Tongan adolescent girls defined by the IOTF and CDC references was 19.4% and 22.8%, respectively, being considerably higher than that of not only juvenile girls but also adolescent boys. Among adolescents, the girls' BMI was positively correlated with fat mass whereas in boys it was not. The sex difference in adolescents was parallel to that in adults, being attributable to gender differences in daily behavioural patterns. CONCLUSIONS: Among Tongan adolescents, obesity prevalence in girls was much higher than in boys, in association with fat accumulation in the former.  相似文献   
85.
A wireless recording system was developed to study the electroencephalogram (EEG) in unrestrained, male Landrace piglets. Under general anesthesia, ball-tipped silver/silver chloride electrodes for EEG recording were implanted onto the dura matter of the parietal and frontal cortex of the piglets. A pair of miniature preamplifiers and transmitters was then mounted on the surface of the skull. To examine whether other bioelectrical activities interfere with the EEG measurements, an electrocardiogram (ECG) or electromyogram (EMG) of the neck was simultaneously recorded with the EEG. Next, wire electrodes for recording movement of the eyelid were implanted with EEG electrodes, and EEG and eyelid movements were simultaneously measured. Power spectral analysis using a Fast Fourier Transformation (FFT) algorithm indicates that EEG was successfully recorded in unrestrained piglets, at rest, during the daytime in the absence of interference from ECG, EMG or eyelid movements. These data indicate the feasibility of using our radiotelemetry system for measurement of EEG under these conditions.  相似文献   
86.
E-cadherin and catenins play key roles in cell adhesion and motility. Little is known about the changes in expression of these molecules in the progression of ovarian carcinomas. In the present study, the immunohistochemical expression of E-cadherin and α-, β-, and γ-catenins was examined in 77 cases of ovarian carcinoma. In addition, the expression of these molecules was evaluated in 26 matched pairs of primary and metastatic lesions of advanced ovarian carcinomas. Of the 77 primary lesions, positive staining for E-cadherin and α-, β-, and γ-catenin was observed in 75 (97%), 63 (82%), 71 (92%) and 57 (74%) cases, respectively. Positivity for E-cadherin and α-, β-, and γ-catenin was significantly decreased in stage III and IV tumors compared with stage I and II tumors, suggesting that expression of the cadherin-catenin complex is reduced with the advancing stages of a tumor. Interestingly, expression of E-cadherin and α-, β-, and γ-catenin in the lesions of peritoneal dissemination was significantly increased compared with the primary lesions. These findings suggest that expression of the cadherin-catenin complex changes markedly and that reexpression may occur during the peritoneal dissemination of ovarian carcinoma cells.  相似文献   
87.
The supplementary motor area (SMA) is a secondary motor area that is involved in various complex hand movements. In animal studies, short latency and probably direct excitatory inputs from SMA to the primary motor cortex (M1) have been established. Although human imaging studies revealed functional connectivity between SMA and M1, its electrophysiological nature has been less studied. This study explored the connection between SMA and M1 in humans using a single-pulse transcranial magnetic stimulation (TMS) over SMA. First, TMS over SMA did not alter the corticospinal tract excitability measured by the size of motor evoked potential elicited by single-pulse TMS over M1. Next, we measured short-interval intracortical facilitation (SICF), which reflects the function of a facilitatory circuit within M1, with or without a single-pulse TMS over SMA. When the intensity of the second pulse in the SICF paradigm (S2) was as weak as 1.0 active motor threshold for a hand muscle, SMA stimulation significantly enhanced the SICF. Furthermore, this enhancement by SMA stimulation was spatially confined and had a limited time window. On the other hand, SMA stimulation did not alter short-interval intracortical inhibition or contralateral silent period duration, which reflects the function of an inhibitory circuit mediated by gamma-aminobutyric acid A (GABAA) or GABAB receptors, respectively. We conclude that a single-pulse TMS over SMA modulates a facilitatory circuit within M1.  相似文献   
88.
Uterine decidualization is crucial for successful implantation and the establishment of pregnancy. In the present study, the expression of insulin-like growth factor-binding protein (IGFBP)-related protein 1 (IGFBP-rP1) in the human uterus and endometrial stromal cells (ESCs) and its physiological significance in decidualization were examined. IGFBP-rP1 protein was localized in the glandular epithelium and stromal cells, and blood vessels in the endometrium. Cultured stromal cells expressed IGFBP-rP1 and secreted it into the medium. IGFBP-rP1 was localized mostly in the cytoplasm near the nucleus. Knocking down the endogenous IGFBP-rP1 expression in stromal cells, by a small interfering (si)RNA, diminished the expression of prolactin and IGFBP-1 which serve as decidual markers. These results suggest that IGFBP-rP1 may play a role in decidualization of ESCs.  相似文献   
89.
The lineage commitment of CD4+ T cells is coordinately regulated by signals through the T cell receptor and cytokine receptors, yet how these signals are integrated remains elusive. Here we find that mice lacking Dock2, a Rac activator in lymphocytes, developed allergic disease through a mechanism dependent on CD4+ T cells and the interleukin 4 receptor (IL-4R). Dock2-deficient CD4+ T cells showed impaired antigen-driven downregulation of IL-4Ralpha surface expression, resulting in sustained IL-4R signaling and excessive T helper type 2 responses. Dock2 was required for T cell receptor-mediated phosphorylation of the microtubule-destabilizing protein stathmin and for lysosomal trafficking and the degradation of IL-4Ralpha. Thus, Dock2 links T cell receptor signals to downregulation of IL-4Ralpha to control the lineage commitment of CD4+ T cells.  相似文献   
90.
Selective loss of dopaminergic neurons is the final common pathway in Parkinson's disease. Expression of Parkin associated endothelin-receptor like receptor (Pael-R) in mouse brain was achieved by injecting adenoviral vectors carrying a modified neuron-specific promoter and Cre recombinase into the striatum. Upregulation of Pael-R in the substantia nigra pars compacta of mice by retrograde infection induced endoplasmic reticulum (ER) stress leads to death of dopaminergic neurons. The role of ER stress in dopaminergic neuronal vulnerability was highlighted by their decreased survival in mice deficient in the ubiquitin-protein ligase Parkin and the ER chaperone ORP150 (150 kDa oxygen-regulated protein). Dopamine-related toxicity was also a key factor, as a dopamine synthesis inhibitor blocked neuronal death in parkin null mice. These data suggest a model in which ER- and dopamine-related stress are major contributors to decreased viability of dopaminergic neurons in a setting relevant to Parkinson's disease.  相似文献   
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