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51.
We report a case of an angiographically documented fistula between the circumflex coronary artery and a left atrial appendage thrombus in a patient with mitral stenosis, flow from which can be demonstrated solely by a color doppler transesophageal echocardiogram. Evaluation of catheter derived hemodynamics and angiographic flow patterns reveals a heretofore undescribed physiologic property of coronary to atrial shunts in patients with mitral stenosis. © 1996 Wiley-Liss, Inc.  相似文献   
52.
Surface treatments are normally carried out after machining. Surface treatment is a costly and time-consuming process. Hence, it makes sense to reduce the requirement of surface treatment as much as possible. Electrical Discharge Machining (EDM) is a frequently used machining process. EDM produces a recast layer on the surface of machined components. The tribological performance of this recast layer is not very well understood. The properties of the recast layer formed as a result of EDM depend upon the discharge current, electrodes and dielectrics. This work aims to study the effects of each on the tribological performance — in terms of the wear depth, friction coefficient, friction force and contact surface temperature of recast layers. Subsequent improvement in the quality of surfaces will significantly reduce the cost and time required to treat surfaces after machining. Hence, various combinations of discharge current, dielectrics and electrodes have been used to characterize and deduce their effects. The tribo-tests are performed in the boundary lubrication regime under pin-on-disc configuration to analyze sliding friction, contact surface temperature and the wear of the recast layers formed on AISI 304L. The surface morphology of the test pins has been performed by Scanning Electron Microscopy (SEM) before and after the tests. The results show that indeed it is possible to control the tribological performance of the recast layers by varying EDM parameters. This approach promises to be a useful methodology to improve the tribological performance of the layers formed after EDM and reduce the time and costs required for surface treatments post machining.  相似文献   
53.
We report, to the best of our knowledge the first case of prosthetic mitral valve mucormycosis caused by Mucor species in an 18-year-old female after mitral valve replacement. She was successfully treated with surgery and antifungal treatment. Mucormycosis was documented by direct demonstration, isolation and histopathological findings of the fungus from embolus and prosthetic mitral valve thrombus.  相似文献   
54.
BACKGROUND: Patients suffering from rosacea may experience frequent blushing and flushing, erythema, telangiectasia, and/or rhinophyma. In an attempt to find effective treatments, many studies have been performed. OBJECTIVE: It is important to be able to evaluate the quality of clinical trials where agents have been used to treat rosacea, and to compare the effectiveness of the different therapies used for this indication. METHODS: The reports on the efficacy and safety of the different drug therapies were evaluated using predetermined criteria. We searched MEDLINE (1966-2002) for studies where rosacea was treated with the various therapies. The criteria used to assess the quality of the studies were: randomization, blinding (double, single, or open), aims clearly defined, prior sample size calculation, whether inclusion and/or exclusion criteria were outlined, baseline comparison of patient characteristics and demographics, interventions and efficacy parameters defined, compliance assessed, statistical analysis performed including intention-to-treat evaluation of efficacy of therapy. RESULTS: Using the above-mentioned criteria, each study was rated in order to determine the quality of the clinical trial. The maximum score a study could attain was 20. To determine if high-quality studies are cited more often than the lower-quality papers, the number of times a study had been cited since its publication was measured. We found 13 of the 42 studies scored greater than 14; these studies were rated as high-quality studies. There was no significant association between high-quality papers and the number of times they had been cited, suggesting that other factors are also taken into consideration when a given study is cited. CONCLUSION: It is important for investigators and clinicians to be aware of the parameters that count towards designing a high-quality protocol since such studies are more likely to reflect efficacy rates that are accurate. Furthermore, it is essential that when a study is written up, the pertinent information regarding the design of the trial and the manner in which it was conducted are conveyed to the reader.  相似文献   
55.
Orofaciodigital syndrome (OFD) can have variable phenotype and presents with oral anomalies, facial dysmorphism, and digital malformations like syndactyly, and polydactyly. Other presentations also include renal and cardiac defects, and central nervous system anomalies like hydrocephalus and cerebellar abnormalities. OFD1 is a X‐linked dominant form of the syndrome presenting in females with mutations in CXorf5 or OFD1 gene. We describe a young child with sparse hairs, milia over face and absence of corpus callosum. Next generation sequencing showed frameshift pathogenic variant in the exon 13 of the OFD1 gene, consistent with diagnosis of OFD1.  相似文献   
56.
Nerve conduction studies in adrenomyeloneuropathy.   总被引:4,自引:1,他引:4       下载免费PDF全文
OBJECTIVE--Adrenomyeloneuropathy (AMN) is an X linked metabolic disorder presenting with progressive spastic paraparesis in the third to fifth decade of life. Although peripheral neuropathy is also present in most patients, prominent pyramidal signs may make its clinical recognition difficult. The objective was to characterise the peripheral neuropathy in patients with AMN by nerve conduction studies. METHODS--Nerve conduction studies were performed in 99 men known to have AMN and in 38 heterozygous women, all of whom had neurological disabilities. RESULTS--Of the 13 variables obtained, at least one was abnormal in 82% of patients. The abnormalities were more common in men than in women (87% v 67%); in legs than in arms (77% v 38%); in motor than in sensory conduction (80% v 39%); and in latency (distal and F wave) and velocity compared with amplitude (80% v 29%). Twenty six patients had at least one nerve variable value in the demyelinating range. Four variables (sural velocity, peroneal amplitude, peroneal velocity, and peroneal F wave) were correlated with the expanded disability status scale; five variables (peroneal velocity, tibial H reflex, median distal latency, median conduction velocity, and median F wave latency) were correlated with serum very long chain fatty acids (VLCFAs); and two variables (sural amplitude and peroneal distal latency) were more likely to be abnormal in patients with normal adrenal function than in patients with Addison's disease. CONCLUSIONS--Nerve conduction studies in patients with AMN are often abnormal and suggest a mixture of axonal loss and multifocal demyelination. Their correlation with disability status and serum VLCFAs suggests that measures from nerve conduction studies may be useful in evaluating future treatments.  相似文献   
57.
58.
Background: Intensive blood pressure (BP) lowering may offer protective effects against major adverse cardiac event (MACE) but is also associated with a greater risk of a serious adverse event (SAE). The risk-benefit profile of intensive versus standard BP control has not been comprehensively assessed. Methods: Four studies were identified from a systematic literature search for randomized controlled trials comparing intensive versus standard BP lowering that reported both MACE and SAE endpoints. A previously described statistical approach was applied to characterize the efficacy-safety tradeoff of BP control. The bivariate outcome was computed to quantitatively assess the net clinical benefit (NCB) of intensive BP lowering as compared to standard treatment, with positive values indicating increased risks and negative values indicating decreased risks. Results: Data from the SPRINT trial demonstrated that intensive strategy was superior in MACE but inferior in SAE, thereby eroding the NCB (bivariate outcome: 0.33% [?0.50% to 1.21%]). Intensive strategy from the SPS3 trial fulfilled non-inferiority in both MACE and SAE but did not reach a favorable NCB (?1.31% [?2.25% to 0.01%]). The ACCORD trial suggested that intensive strategy was non-inferior in MACE but inferior in SAE (?0.19% [?0.79% to 1.37%]). Results from the VALISH trial were inconclusive for SAE but suggested non-inferiority in MACE (?1.19% [?3.24% to 0.68%]). Conclusions: Compared to the standard blood pressure target, pooled data from randomized controlled trials suggest that intensive strategy did not achieve a net clinical benefit when weighing the benefit of MACE reduction against the risk of SAE under the bivariate framework.Abbreviations: Blood pressure (BP), diastolic blood pressure (DBP), major adverse cardiac event (MACE), net clinical benefit (NCB), serious adverse event (SAE), systolic blood pressure (SBP).  相似文献   
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60.
Mycoplasma pneumoniae, a self-replicating cell wall-deficient prokaryote, has a differentiated terminal organelle that is essential for cytadherence and gliding motility. P30, an important protein associated with the terminal organelle, is required for the cytadherence and virulence of M. pneumoniae. P30 is a transmembrane protein with an intracytoplasmic N terminus and an exposed C terminus. In the present study, we amplified and sequenced the full-length p30 gene of Mycoplasma pneumoniae directly from 18 Indian asthmatic patients. Sequence diversity was observed in the p30 genes from 16 clinical samples when the sequences were compared with the sequence of strain M-129. We also successfully expressed a fragment of the p30 gene (P30B) that includes the complete C-terminal proline-rich amino acid sequences in different Escherichia coli expression systems. The maltose binding protein (MBP)-P30B fusion protein was recognized by M. pneumoniae-infected patient sera in immunoblots, and the protein was immunogenic in mice. We further analyzed the reactivity of the MBP-P30B fusion protein with patient sera in an enzyme-linked immunosorbent assay (ELISA) and compared it with the reactivity obtained with a commercial kit (the Serion ELISA Classic kit). The sensitivity and the specificity of the in-house ELISA were 78.57% and 89.47%, respectively. This study suggests that the P30 protein can be used as an antigen along with other adhesin proteins for the immunodiagnosis of M. pneumoniae infection.  相似文献   
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