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741.
  • The femoropopliteal (FP) artery is a common site for endovascular interventions.
  • S.M.A.R.T.® stent is effective in treating FP lesions with results comparable to other treatment options.
  • Without head‐to‐head randomized controlled trials, the ideal treatment strategy for FP lesions remains unknown.
  相似文献   
742.
Background: colorectal cancer (CRC) is one of the most common cancers in developed countries. Annually, over one million of new cases in the world are recorded. Majority of CRCs occur sporadically with dominant phenotype of chromosomal instability (CIN). Permanent exposure to DNA damaging agents such as ionizing radiation result in DNA double-stranded breaks, which create favorable conditions for chromosomal aberration to arise. Homologous recombination repair (HRR) is the leading process engaged in maintaining of the genome integrity. RAD51 protein was recognized as crucial in HRR. Single nucleotide polymorphisms are the primary source of genetic variation which presence in the RAD51 promoter region can affect on its expression and consequently modulate HR efficiency. Objectives: The aim of this study was to analyze the distribution of genotypes and allele frequencies of -4791A/T and -4601A/G RAD51 gene polymorphisms, followed by an assessment of their relationship with the risk of CRC. Material and methods: The study included 115 patients with confirmed CRC. Control group was consisted of 118 cancer-free individuals with a negative family history. The genotypes were identified by PCR-RFLP method. Conclusion: This study revealed statistically significant association between appearance of G/A genotype in position -4601 of RAD51 gene and CRC risk.  相似文献   
743.
744.
745.
The current paper presents a case of unique presentation of idiopathic uveal effusion syndrome. The 28 years old patient with combined bilateral choroidal and retinal detachment, recurrent in the left eye, underwent surgical procedures. He was treated with lamellar sclerectomy under the scleral flap in both eyes and another sclerectomy in the left eye later on. The apposition of the retina was achieved in both eyes and visual acuity improved significantly. Three months later, the patient developed anterior ischemic optic neuropathy in the right eye. In left eye after cataract phacoemulsification, persisted cystoid macular edema appeared.  相似文献   
746.
Elevated levels of glucocorticoids exert neurotoxic effects, and the hippocampus is particularly sensitive to the effects of glucocorticoids. Because some data have indicated that an increased action of glucocorticoids in the perinatal period enhances the susceptibility of brain tissue to adverse substances later in life, the main purpose of the present study was to compare necrotic/apoptotic corticosterone action in hippocampal organotypic cultures obtained from control animals with the effect of this steroid in tissue from prenatally stressed rats. Because the adverse effects of glucocorticoid action on nerve cell viability appear to result mainly from an increase in the intensity of the effects of glutamate and changes in growth factor and pro-inflammatory cytokine synthesis, the involvement of these factors in corticosterone action were also determined. In stress-like concentration (1 μM), corticosterone, when added to hippocampal cultures for 1 and 3 days, alone or jointly with glutamate, did not induce necrosis. In contrast, in 3-day cultures, corticosterone (1 μM) increased caspase-3 activity and the mRNA expression of the pro-apoptotic Bax. Moreover, corticosterone’s effect on caspase-3 activity was stronger in hippocampal cultures from prenatally stressed compared to control rats. Additionally, 24 h of exposure to corticosterone and glutamate, when applied separately and together, increased Bdnf, Ngf, and Tnf-α expression. In contrast, after 72 h, a strong decrease in the expression of both growth factors was observed, while the expression of TNF-α remained high. The present study showed that in stress-like concentrations, corticosterone exerted pro-apoptotic but not necrotic effects in hippocampal organotypic cultures. Prenatal stress increased the pro-apoptotic effects of corticosterone. Increased synthesis of the pro-inflammatory cytokine TNF-α may be connected with the adverse effects of corticosterone on brain cell viability.  相似文献   
747.

Objectives

The purpose of this study is to assess the preoperative evaluation of an adnexal mass using the GI-RADS classification and to verify whether CA-125 measurement can offer any additional benefits to the GI-RADS-based prediction of ovarian tumor malignancy.

Material and methods

In this study, we assessed a total of 215 women with an adnexal tumor using the GI-RADS classification combined with CA-125 measurement. All adnexal masses underwent histological verification.

Results

Of a total of 215 lesions, we classified 2 lesions as GI-RADS 2 (0.9%), 118 lesions as GI-RADS 3 (54.9%), 86 lesions as GI-RADS 4 (40.0%) and 9 lesions as GI-RADS 5 (4.2%). For GI-RADS 4–5 lesions, the sensitivity, specificity, PPV, NPV, ACC and OR were as follows: 94.3, 72.2, 52.6, 97.5, 77.7%, and 43.3 (CI 12.0–146), respectively. The corresponding parameters resulting from combining the GI-RADS classification with the CA-125 marker were as follows: 66.0, 93.8, 77.8, 89.4, 87.0%, and 29.6 (CI 12.6–69.6), respectively, with p?<?0.001. For Ca-125?>?30 IU/mL alone, the results were as follows: 70.0, 80.3, 53.8, 89.1, 77.7%, and 9.5 (4.6–19.6), respectively, with p?<?0.0001.Additionally, 47.8% of the patients had no symptoms, 36.5% had back pain, 5.2% had an increased abdominal size, 4.3% had menstrual irregularities and 2.6% had constipation. There were 152 benign and 18 malignant cases in the low risk group (GIRADS 1–3 and GIRADS 4?+?CA-125?<?30 IU/mL) and 10 benign and 35 malignant tumors in the high-risk group (GIRADS 4?+?CA125?>?30 IU/mL and GIRADS 5).

Conclusions

GI-RADS classification had good performance in discriminating ovarian tumors. The additional measurement of CA-125 improves the system specificity, PPV and ACC for preoperative adnexal tumor assessment.
  相似文献   
748.
Experienced video game players exhibit superior performance in visuospatial cognition when compared to non‐players. However, very little is known about the relation between video game experience and structural brain plasticity. To address this issue, a direct comparison of the white matter brain structure in RTS (real time strategy) video game players (VGPs) and non‐players (NVGPs) was performed. We hypothesized that RTS experience can enhance connectivity within and between occipital and parietal regions, as these regions are likely to be involved in the spatial and visual abilities that are trained while playing RTS games. The possible influence of long‐term RTS game play experience on brain structural connections was investigated using diffusion tensor imaging (DTI) and a region of interest (ROI) approach in order to describe the experience‐related plasticity of white matter. Our results revealed significantly more total white matter connections between occipital and parietal areas and within occipital areas in RTS players compared to NVGPs. Additionally, the RTS group had an altered topological organization of their structural network, expressed in local efficiency within the occipito‐parietal subnetwork. Furthermore, the positive association between network metrics and time spent playing RTS games suggests a close relationship between extensive, long‐term RTS game play and neuroplastic changes. These results indicate that long‐term and extensive RTS game experience induces alterations along axons that link structures of the occipito‐parietal loop involved in spatial and visual processing.  相似文献   
749.

Objective

We sought to determine whether the presence or surgical removal of certain nodes in a connectivity network constructed from intracranial electroencephalography recordings determines postoperative seizure freedom in surgical epilepsy patients.

Methods

We analyzed connectivity networks constructed from peri-ictal intracranial electroencephalography of surgical epilepsy patients before a tailored resection. Thirty-six patients and 123 seizures were analyzed. Their Engel class postsurgical seizure outcome was determined at least one year after surgery. Betweenness centrality, a measure of a node’s importance as a hub in the network, was used to compare nodes.

Results

The presence of larger quantities of high-betweenness nodes in interictal and postictal networks was associated with failure to achieve seizure freedom from the surgery (p?<?0.001), as was resection of high-betweenness nodes in three successive frequency groups in mid-seizure networks (p?<?0.001).

Conclusions

Betweenness centrality is a biomarker for postsurgical seizure outcomes. The presence of high-betweenness nodes in interictal and postictal networks can predict patient outcome independent of resection. Additionally, since their resection is associated with worse seizure outcomes, the mid-seizure network high-betweenness centrality nodes may represent hubs in self-regulatory networks that inhibit or help terminate seizures.

Significance

This is the first study to identify network nodes that are possibly protective in epilepsy.  相似文献   
750.
Several types of specialized glucose transporters (GLUTs) provide constant glucose transport from the maternal circulation to the developing fetus through the placental barrier from the early stages of pregnancy. GLUT1 is a prominent protein isoform that regulates placental glucose transfer via glucose-facilitated diffusion. The GLUT1 membrane protein density and permeability of the syncytial basal membrane (BM) are the main factors limiting the rate of glucose diffusion in the fetomaternal compartment in physiological conditions. Besides GLUT1, the GLUT3 and GLUT4 isoforms are widely expressed across the human placenta. Numerous medical conditions and molecules, such as hormones, adipokines, and xenobiotics, alter the GLUT’s mRNA and protein expression. Diabetes upregulates the BM GLUT’s density and promotes fetomaternal glucose transport, leading to excessive fetal growth. However, most studies have found no between-group differences in GLUTs’ placental expression in macrosomic and normal control pregnancies. The fetomaternal GLUTs expression may also be influenced by several other conditions, such as chronic hypoxia, preeclampsia, and intrahepatic cholestasis of pregnancy.  相似文献   
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