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991.
Implantation of specifically designed left ventricular (LV) lead is a relatively complex procedure that depends on the anatomy of the coronary veins, available instrumentation, and experience of the operator. In patients with dilated cardiomyopathy (DCM) tortuosity of the selected branch of coronary sinus (CS) leads to difficult or failed LV placement. A case study of a 45-year-old woman with DCM requiring lead placement is presented here. To plan for proper LV lead positioning, CS angiography was obtained through right femoral vein approach with preshaped long sheath (SJM, SL3) and occlusive balloon. For successful implant of LV lead, with no viable alternatives available, the tortuosity of the lateral and posterolateral branch were overcome by advancing and inflating the balloon in the main CS to deflect LV lead into the target branch. A unipolar LV lead (Medtronic 4193) was finally placed in a true posterolateral position with excellent sensing and pacing threshold without phrenic nerve stimulation.  相似文献   
992.
993.
Several epidemiologic studies have found that smokers with chronic obstructive pulmonary disease (COPD), an inflammatory disease of the lung, have an increased risk of lung cancer compared with smokers without COPD. We have shown a causal role for COPD-like airway inflammation in lung cancer promotion in the CCSP(Cre)/LSL-K-ras(G12D) mouse model (CC-LR). In contrast, existing epidemiologic data do not suggest any definite association between allergic airway inflammation and lung cancer. To test this, CC-LR mice were sensitized to ovalbumin (OVA) and then challenged with an OVA aerosol weekly for 8 weeks. This resulted in eosinophilic lung inflammation associated with increased levels of T helper 2 cytokines and mucous metaplasia of airway epithelium, similar to what is seen in asthmatic patients. However, this type of inflammation did not result in a significant difference in lung surface tumor number (49 ± 9 in OVA vs. 52 ± 5 in control) in contrast to a 3.2-fold increase with COPD-like inflammation. Gene expression analysis of nontypeable Haemophilus influenzae (NTHi)-treated lungs showed upregulation of a different profile of inflammatory genes, including interleukin 6 (IL-6), compared with OVA-treated lungs. Therefore, to determine the causal role of cytokines that mediate COPD-like inflammation in lung carcinogenesis, we genetically ablated IL-6 in CC-LR mice. This not only inhibited intrinsic lung cancer development (1.7-fold) but also inhibited the promoting effect of extrinsic COPD-like airway inflammation (2.6-fold). We conclude that there is a clear specificity for the nature of inflammation in lung cancer promotion, and IL-6 has an essential role in lung cancer promotion.  相似文献   
994.

Background and Aims

Determining the stage of liver fibrosis and the grade of necroinflammation is important in predicting the prognosis and treatment response of patients with chronic viral hepatitis. Liver biopsy is associated with several technical problems and complications; therefore, its repetitive performance as a procedure in evaluating treatment response and in following up patients is not recommended. This study was performed to determine the correlation of serum hyaluronic acid (HA) levels with the stage and grade of histopathologic liver changes in patients with chronic hepatitis B and C.

Methods

This analytical cross-sectional study was performed on 69 patients with chronic hepatitis B or C in Mashhad, Iran, who were referred to our clinic and underwent liver biopsy and blood sampling simultaneously in 2006-2007. None of the patients were on medication that would affect the serum levels of (HA) and patients with signs of arthropathy were excluded from the study.

Results

Out of the 69 patients i this study, 48 (69.6%) were male and 21 (30.4%) were female. The causative virus in 29 patients (42%) was hepatitis C and in the rest (n = 40, 58%) hepatitis B. The severity of liver fibrosis (stage) had a direct correlation (r = 0.25, P = 0.042) with the levels of (HA) and an inverse correlation with the platelet level (r = 0.37, P = 0.002). The degree of liver necroinflammation (grade) did not have a significant correlation with the levels of (HA) and alanine transaminase (r = -0.01, P = 0.9; r = 0.21, P = 0.09 respectively); instead, there was an inverse correlation with platelet levels (r = 0.36, P = 0.003).

Conclusions

Our study results correspond with those of other international studies; thus suggesting that the (HA) serum level is a useful marker in determining the severity of fibrosis in patients with chronic viral hepatitis. To form a definite conclusion, further studies on large groups should be performed.  相似文献   
995.
In the effort to identify and manage sex offenders, the differences between legal and medical/psychiatric terminology and approaches are readily apparent. This article discusses the different definitions and approaches of the two fields and considers both the behaviors that create risk to others and the strategies for reducing that risk. Particular attention is paid to the subcategory of paraphilic sex offenders. Treatment goals, modalities, and efficacies are discussed, as are evolving legal strategies for risk control and the need for interaction between law and medicine/psychiatry in order to accomplish common goals of risk management.  相似文献   
996.
997.
998.
The sphenoid bony landmarks are important for endoscopic orientation in skull base surgery but show a wide range of variations. We aimed to describe an instructional model for the endoscopic parasellar anatomy in sphenoid sinuses with ill-defined bony landmarks. Five preserved injected cadaveric heads and four sides of dry skulls were studied endoscopically via transethmoid, transsphenoidal approach. The parasellar region was exposed by drilling along the maxillary nerve (V2) canal [the length of the foramen rotundum (FR) between the middle cranial fossa and the pterygopalatine fossa]. This was achieved by drilling in the inferior part of the lateral wall of posterior ethmoids immediately above the sphenopalatine foramen. Cavernous V2 was traced to the paraclival internal carotid artery (ICA). Cavernous sinus (CS) apex was exposed by drilling a triangle bounded by V2 and its canal inferiorly, bone between FR and superior orbital fissure (SOF) anteriorly, and ophthalmic nerve (V1) superiorly. Drilling was continued toward the annulus of Zinn (AZ) and optic nerve superiorly and over the intracavernous ICA posteriorly. Endoscopic measurements between V2, SOF, AZ, and opticocarotid recess were obtained. Endoscopic systematic orientation of parasellar anatomy is presented that can be helpful for approaching sphenoid sinus with ill-defined bony landmarks.  相似文献   
999.
The prevalence of primary cardiac tumour ranges from 0.0017-0.28% and papillary fibroelastoma is rare but not uncommon benign cardiac neoplasm. Currently, with the advent of higher-resolution imaging technology especially transoesophageal echocardiography such cases being recognized frequently. The clinical presentation of these tumours varies from asymptomatic to severe ischaemic or embolic complications. We herein, present a 50-year-old female patient with a papillary fibroelastoma of the aortic valve arising from the endocardium of the right coronary cusp very close to the commissure between the right and non-coronary cusps. The patient presented with angina-like chest pain and was investigated using echocardiography and CT angiographic modalities in addition to the usual investigations. The differential diagnosis considered was a thrombus, myxoma, Lambl's excrescence and infective vegetation. The surgical management included a prompt resection of the tumour on cardiopulmonary bypass avoiding injury to the aortic valve. The patient recovered well. A review of the literature suggests that the cardiac papillary fibroelastoma is a rare but potentially treatable cause of embolic stroke and other fatal complications, therefore, a strong suspicion; appropriate use of imaging modality, preoperative anticoagulation and urgent surgical resection is warranted. Also, possibility of this diagnosis should be kept in mind while managing cardiac or valvular tumours.  相似文献   
1000.
Mutations within the coding region of hepatitis B surface antigen (HBsAg) have been found naturally in chronic carriers. To characterize the mutations of HBsAg from Iranian chronic carriers who were vaccine and/or medication naive. The surface genes from 360 patients were amplified and directly sequenced. The distribution of amino acid substitutions was classified according to different immune epitopes of the surface protein. All isolates belonged to genotype D . 222 (61.6%) of 360 patients contained at least one amino acid substitution. 404 (74.5%) of 542 amino acid changes occurred in different immune epitopes of HBsAg, of which 112 (27.7%) in 32 residues of B‐cell epitopes (62 in the ‘a’ determinant); 111 (27.4%) in 32 residues of T helper; and 197 (48.7%) in 32 residues inside cytotoxic T lymphocyte (CTL) epitopes. One Th (186–197) and two CTL (28–51 and 206–215) epitopes were found to be hotspot motifs for the occurrence of 213 (52.7%) substitutions. 20 stop codons were identified in different epitopes. There was a significant association between amino acid substitutions and anti‐HBe seropositivity; however, the correlation between such changes with viral load and ALT levels was not significant. In chronic hepatitis B virus(HBV) carriers, positive selection in particular outside the ‘a’ determinant appeared to exert influence on the surface proteins. These changes could be immune escape mutations naturally occurring due to the host immune surveillance especially at the T‐cell level.  相似文献   
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