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101.
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Delayed treatment of stroke with recombinant tissue plasminogen activator (r‐tPA) induces overexpression of matrix metalloproteinase 9 (MMP‐9) which leads to breakdown of the blood–brain barrier (BBB) and causes more injuries to the brain parenchyma. In this study, the effect of ascorbic acid (AA), an antioxidant agent, on the delayed administration of r‐tPA in a rat model of permanent middle cerebral artery occlusion (MCAO) was investigated. Forty male rats were randomly divided into four groups: untreated control rats (ischaemic animals), AA‐treated (500 mg/kg; 5 hr after stroke) rats, r‐tPA‐treated (5 hr after stroke 1 mg/kg) rats and rats treated with the combination of AA and r‐tPA. Middle cerebral artery occlusion was induced by occluding the right middle cerebral artery (MCA). Infarct size, BBB, brain oedema and the levels of MMP‐9 were measured at the end of study. Neurological deficits were evaluated at 24 and 48 hr after stroke. Compared to the control or r‐tPA‐treated animals, AA alone (p < 0.001) or in combination with r‐tPA (p < 0.05) significantly decreased infarct volume. Ascorbic acid alone or r‐tPA + AA significantly reduced BBB permeability (p < 0.05), levels of MMP‐9 (p < 0.05 versus control; p < 0.01 versus r‐tPA) and brain oedema (p < 0.001) when compared to either the control or the r‐tPA‐treated animals. Latency to the removal of sticky labels from the forepaw was also significantly decreased after the administration of AA + r‐tPA (p < 0.05) at 24 or 48 hr after stroke. Based on our data, acute treatment with AA may be considered as a useful candidate to reduce the side effects of delayed application of r‐tPA in stroke therapy.  相似文献   
103.
The critical role of metal ions and in particular iron in oxidative stress and protein aggregation offers chelation therapy as a sensible pharmaceutical strategy in oxidative stress‐induced neuronal damages. In this research, we conjugated an iron‐chelating agent, deferasirox, to cationized human serum albumin molecules in order to develop a novel brain delivery system for the management of neurodegenerative disorders due to the significant role of oxidative stress‐induced neuronal injury in such diseases. Cationized albumin is known to be able to transport to brain tissue via adsorptive‐mediated transcytosis. The developed structures were molecularly characterized, and their conjugation ratio was determined. PC12 cell line was utilized to evaluate the neuroprotective features of these newly developed molecules in the presence of hydrogen peroxide neuronal damage and to identify the mechanisms behind the observed neuronal protection including apoptotic and autophagic pathways. Furthermore, a rat model of Alzheimer's disease was utilized to evaluate the impact of conjugated structures in vivo. Data analysis revealed that the conjugated species were able to hinder apoptotic cell death while enhancing autophagic process. The developed conjugated species were also able to attenuate amyloid beta‐induced learning deficits when administered peripherally.  相似文献   
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Cardiac masses diagnosis and treatment are a true challenge, although they are infrequently encountered in clinical practice. They encompass a broad set of lesions that include neoplastic (primary and secondary), non-neoplastic masses and pseudomasses. The clinical presentation of cardiac tumors is highly variable and depends on several factors such as size, location, relation with other structures and mobility. The presumptive diagnosis is made based on a preliminary non-invasive diagnostic work-up due to technical difficulties and risks associated with biopsy, which is still the diagnostic gold standard. The findings should always be interpreted in the clinical context to avoid misdiagnosis, particularly in specific conditions (e.g., infective endocarditis or thrombi). The modern multi-modality imaging techniques has a key role not only for the initial assessment and differential diagnosis but also for management and surveillance of the cardiac masses. Cardiovascular magnetic resonance (CMR) allows an optimal non-invasive localization of the lesion, providing multiplanar information on its relation to surrounding structures. Moreover, with the additional feature of tissue characterization, CMR can be highly effective to distinguish pseudomasses from masses, as well as benign from malignant lesions, with further differential diagnosis of the latter. Although histopathological assessment is important to make a definitive diagnosis, CMR plays a key role in the diagnosis of suspected cardiac masses with a great impact on patient management. This literature review aims to provide a comprehensive overview of cardiac masses, from clinical and imaging protocol to pathological findings.  相似文献   
106.
Aneurysm of the inferior vena cava is a rare anomaly with a very few reported cases worldwide. We report the case of a 26-years-old man with acute severe abdominal pain and hypovolemic shock following an episode of syncope. Ultrasonography showed a fusiform aneurysmal dilation of the infra-hepatic inferior vena cava (IVC), with a large saccular portion at its posterolateral wall and mural thrombosis. Abdominal computed tomography scan revealed extension to the right renal vein and adhesion to the right kidney. The saccular aneurysm and the right kidney were resected, and anatomopathological examination revealed a cavernous hemangioma. All symptoms disappeared after surgery. This is the first reported case of symptomatic congenital saccular aneurysm of the IVC due to mural vascular malformation and with involvement of the right kidney leading to nephrectomy.  相似文献   
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BackgroundComplementary and alternative medicines have been used to increase comfort and relaxation in mothers during labor. Comforting and preparing the mother in labor can create a positive birth experience. The aim of this study was to evaluate the effect of acupressure on childbirth satisfaction and the experience of giving birth in women with full-term pregnancy, before the onset of labor.MethodsIn 2016, a randomized clinical trial study was conducted in Shahid Akbar Abadi Hospital, Tehran, Iran, enrolling 120 pregnant women at 39–40 gestational weeks with no signs of the onset of labor. They were divided randomly into acupressure, sham acupressure, and control groups. Acupressure points including SP6, BL 60, and BL 32 were pressured bilaterally. Interventions were performed by the researcher, the mother and her relative (husband). Childbirth satisfaction was measured 24 h after delivery. The collected data were analyzed by SPSS software and comparing tests were Chi-squared, Kruskal-Wallis, ANOVA tests (P ≤ 0.05).ResultsThe total childbirth satisfaction did not differ significantly among the three groups (P = 0.460), but the acupressure group had a higher level of satisfaction than the other two groups. Moreover, statistical tests regarding the expectations of the childbirth experience showed a significant difference among the groups (P = 0.033). The actual birth was closest to the expectations of subjects in the acupressure group.ConclusionThis study demonstrated that acupressure may be used as a method in order to attempt to provide a good birth experience and satisfaction of childbirth.  相似文献   
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All‐ceramic crowns for teeth are widely used for restoring teeth. Stone casts have been made from conventional impression methods; however, newer techniques have made this process easier and faster for both the patient and the practitioner. Laboratory CAD/CAM technology mainly involves scanning the die stone, while other systems permit impression or intraoral scanning; however, one major concern remaining is the marginal fit of the restorations made using different methods for recording the prepared teeth. This study aims to review studies evaluating the marginal fit of all‐ceramic crowns manufactured by CAD/CAM systems using different extra‐ and intra‐oral scanners compared to conventional impressions.  相似文献   
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