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81.
PurposeNon-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO3 (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.MethodsFourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.ResultsBC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016).ConclusionUTE MRI and UTE subtraction can depict CC bright.  相似文献   
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Multiple system atrophy (MSA) is an oligodendrogliopathy of presumably sporadic origin, characterized by prominent α‐synuclein inclusions with neuronal multisystem degeneration, although a few Mendelian pedigrees have been reported. Here we report two familial cases of MSA of unknown genetic background. One patient was diagnosed as a possible MSA‐C (cerebellar dysfuntion) case, and the other as clinically possible MSA‐P (parkinsonism), which turned out to be definite MSA, based on a detailed autopsy. The neuropathology showed extensive deposition of α‐synuclein in the glia as well as in the neurons located in the cerebral cortices and hippocampal systems, although neither multiplication of the SNCA gene or mutations in COQ2 gene were identified in the family concerned.  相似文献   
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The anticonvulsant activity of 2-[N-(4-chlorophenyl)-N-methylamino]-4H-pyrido[3.2-e]-1,3-thiazin-4-one (YM928), a novel alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist, was studied in animal models of generalized seizure. YM928 exerted significant anticonvulsant effects in the maximal electroshock (MES) seizure test (ED50 = 7.4 mg/kg p.o.), pentylenetetrazol (PTZ)-induced seizure test (ED50 = 9.6 mg/kg p.o.), AMPA-induced seizure test (ED50 = 5.5 mg/kg p.o.), and strychnine-induced seizure test (ED50 = 14.0 mg/kg p.o.) in mice. Effects in rats were detected in the MES seizure test (ED50 = 4.0 mg/kg p.o.) and PTZ-induced seizure test (ED50 = 6.2 mg/kg p.o.). The profile of YM928 was compared with that of established antiepileptics. Valproate showed beneficial effects in all tests used. In contrast, carbamazepine, phenytoin, lamotrigine, phenobarbital, diazepam, ethosuximide, and gabapentin were not active against seizures induced by at least one stimulant. In the rotarod test, YM928 impaired motor coordination (TD50 = 22.5 mg/kg p.o.). The protective index (TD50 value of the rotarod test/ED50 value of MES seizure) was 3.0, suggesting that YM928 can exert antiepileptic effects with only minor motor disturbances. YM928 at doses of 2, 4, and 8 mg/kg p.o. did not significantly affect the threshold of electroshock seizure in rats after 16 days of repeated administration. These data indicate that YM928 does not induce tolerance after subchronic administration. These results indicate that YM928 is a broad-spectrum anticonvulsant that would prove useful for the treatment of generalized seizure in human epileptic patients.  相似文献   
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Tripartite motif protein 29 (TRIM29) is one of the TRIM family proteins, some of which function as E3 ubiquitin ligases. In this study, we investigated the usefulness of TRIM29 for diagnosis of prostate cancer. Prostate tissues including carcinoma and non-carcinoma tissues obtained by needle biopsy and radical prostatectomy were used. Immunohistochemistry was performed according to standard procedures using an antibody against TRIM29. Immunohistochemical staining with an antibody against 34βE12, which recognizes cytokeratins 1, 5, 10 and 14, was performed as a control. Basal cells of normal prostatic glands were stained with anti-TRIM29 antibody in all cases, whereas prostate cancer tissues had no or little staining with anti-TRIM29 antibody. TRIM29 is selectively expressed in basal cells of the normal prostate gland, and immunohistochemical staining with anti-TRIM29 antibody showed the same expression pattern as that with 34βE12 in prostate cancer and its benign mimics. Our data indicate that TRIM29 may be useful for distinguishing prostate cancers from benign tissues.  相似文献   
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Metabolic alteration is increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types, and metabolically targeted therapies could become important strategies for reducing fibrosis. In present study, target enzymes that are involved in changes in phospholipid metabolism during fibroblast-to-myofibroblast transition induced by transforming growth factor beta 1 (TGF-β1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-β1 stimulation, 17 lipids decreased and 17 increased. The latter included the phospholipids phosphatidylcholine (PC), phosphatidylserine (PS), and phosphatidylethanolamine (PE). Furthermore, among the rate-limiting enzymes that regulate these phospholipids, phosphatidylserine decarboxylase (PISD), which controls conversion of PS to PE and is localized in mitochondria, decreased in response to TGF-β1. Knockdown of PISD alone without TGF-β1 stimulation increased expression of α-smooth muscle actin mRNA and production of total collagen. Taken together, these results indicate that PISD is involved in the mechanism of fibrogenesis by regulating phospholipid metabolism.  相似文献   
90.

Objectives

Digital subtraction radiography (DSR) is a suitable technique for detecting incipient bone changes. However, in DSR, one or more follow-up radiographs must be taken. The aim of this study was to assess the possibility of reducing the exposure time for the radiographs that follow the initial one.

Methods

Maxillary premolar and molar radiographic images of a dry skull were taken with a digital radiography system. The initial radiographs, without bone chips, were taken at 0.32 and 0.16 s. Then, five bone chips (weight range 7–15 mg) were placed on the maxillary molar buccal side of the dry skull. Secondary radiographs were taken at 0.32-, 0.16-, 0.08-, 0.04-, and 0.02-s exposure times. For each bone chip, radiographs were taken three times. The secondary and initial images were subtracted to yield subtraction images. Four observers were asked to evaluate bone change visibility in the subtraction images. The Friedman test was used for statistical analysis.

Results

Significant differences were seen at each of the settings for the 0.32-s group (p = 1.24e?030) and 0.16-s group (p = 7.52e?009). By comparing the different groups, observer evaluations indicated that visibility changed when the secondary radiograph was taken at 1/8 of the exposure time of the initial radiograph. In both groups, the visibility of the 0.02-s subtraction image was significantly lower than that of the other subtraction images.

Conclusion

In DSR, the exposure time of the secondary radiograph can be reduced to 1/4 of the exposure time of the initial radiograph.  相似文献   
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