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81.
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83.
Microfracture repair tissue in young adult humans and in rabbit trochlea is frequently of higher quality than in corresponding ovine or horse models or in the rabbit medial femoral condyle (MFC). This may be related to differences in subchondral properties since repair is initiated from the bone. We tested the hypothesis that subchondral bone from rabbit trochlea and the human MFC are structurally similar. Trochlea and MFC samples from rabbit, sheep, and horse were micro‐CT scanned and histoprocessed. Samples were also collected from normal and lesional areas of human MFC. The subchondral bone of the rabbit trochlea was the most similar to human MFC, where both had a relatively thin bone plate and a more porous and less dense character of subchondral bone. MFC from animals all displayed thicker bone plates, denser and less porous bone and thicker trabeculae, which may be more representative of older or osteoarthritic patients, while both sheep trochlear ridges and the horse lateral trochlea shared some structural features with human MFC. Since several cartilage repair procedures rely on subchondral bone for repair, subchondral properties should be accounted for when choosing animal models to study and test procedures that are intended for human cartilage repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:63–70, 2015.
  相似文献   
84.
Transient left ventricular (LV) cavitary dilation during dipyridamole-thallium imaging was reported in 45 of 510 (9%) consecutive patients referred for dipyridamole-thallium imaging. Clinical and hemodynamic effects observed during dipyridamole infusion were not predictive of transient cavitary dilation on the thallium images. Coronary angiography was performed in 32 of the 45 patients: 75% had either left main, 3-vessel or "high-risk" 2-vessel coronary artery disease. Although 25 of 45 patients (56%) with transient cavitary dilation were either asymptomatic or had only grade 1/4 effort angina, 16 of 25 patients (64%) not referred for coronary revascularization sustained a cardiac event during a mean follow-up of 12 months. Most events were cardiac deaths (75%) and 87% of events occurred within 4 months of the test. Noncardiac surgery was performed in 187 of the 510 patients. The postoperative cardiac event rate was 2% in the 101 patients with normal scans or fixed defects, 19% in 75 patients with reversible perfusion defects and 58% in 12 patients with reversible cavitary dilation (p less than 0.0001). Thus, transient LV dilation during dipyridamole-thallium imaging is a marker of severe underlying coronary artery disease, denotes a poor prognosis and predicts a high risk of postoperative cardiac complications in patients who undergo noncardiac surgery.  相似文献   
85.
Two cases are reported of atypical relapses of pneumocystosis in AIDS patients treated with aerosol pentamidine for 14 and 22 months. These pneumopathies are unusual because of their pitted aspect and recurrent spontaneous pneumothoraxes in spite of repeated drainage. They are difficult to diagnose because bronchoalveolar lavage fluid is negative for Pneumocystis carinii, despite their presence in lung biopsies. Histological lesions vary, being granulomatous, necrotizing and invasive, with involvement of the pleura and lymph nodes. Although a highly effective therapy against P. carinii pneumonia, aerosol pentamidine may play a role in these atypical episodes: either by causing bronchial obstructions beyond which the pneumocytotic lesions cannot be reached by lavage and become necrotic, or by favoring the extrapulmonary spread of P. carinii.  相似文献   
86.
Lung transplantation (LTx) is a valid therapeutic option for selected patients with end‐stage lung disease. Soluble HLA‐G (sHLA‐G) has been associated with increased graft survival and decreased rejection episodes in solid organ transplantation. HLA‐G haplotypes named UTRs, defined by SNPs from both the 5′URR and 3′UTR, have been reported to reliably predict sHLA‐G level. The aim of this retrospective study was to determine the impact of HLA‐G alleles and UTR polymorphism from LTx recipients on anti‐HLA allo‐immunization risk, overall survival and chronic rejection (CLAD). HLA‐G SNPs were genotyped in 124 recipients who underwent LTx from 1996 to 2010 in Marseille, 123 healthy individuals and 26 cystic fibrosis patients not requiring LTx. sHLA‐G levels were measured for 38 LTx patients at D0, M3 and M12 and for 123 healthy donors. HLA‐G*01:06~UTR2 was associated with a worse evolution of cystic fibrosis (p = 0.005) but not of long‐term survival post‐LTx. HLA‐G*01:04~UTR3 haplotype was associated with lower levels of sHLA‐G at D0 and M3 (p = 0.03), impaired long‐term survival (p = 0.001), increased CLAD occurrence (p = 0.03) and the production of de novo donor‐specific antibodies (DSA) at M3 (p = 0.01). This study is the first to show the deleterious association of different HLA‐G alleles and UTRs in LTx.  相似文献   
87.
We implanted stents in three patients who had traumatic abdominal aortic dissections, complicated by right limb ischemia in one case. The circulating false channel extended to the left iliac artery in one case and to both iliac arteries in the last case. Diagnosis and radiological follow-up included ultrasound, computed tomography, and arteriography. Two patients were treated with Wallstents, one with a Palmaz stent. The occlusion of the false channel was obtained in all patients without any significant residual stenosis. No early or late complication was noted in any of the patients. The longest follow-up was 2 years. We conclude that stent placement is an efficient method for the treatment of noniatrogenic inframesenteric aortic dissections. Received: 0/00/00/Accepted: 0/00/00  相似文献   
88.

Objectives

To measure the frequency of infraorbital nerve enlargement (IONE) on magnetic resonance imaging (MRI) in European patients suffering from an IgG4-related ophthalmic disease (IgG4-ROD) as compared to patients suffering from non-IgG4-related ophthalmic disease (non-IgG4-ROD).

Methods

From January 2006 through April 2015, 132 patients were admitted for non-lymphoma, non-thyroid-related orbital inflammation. Thirty-eight had both pre-therapeutic orbital MRI and histopathological IgG4 immunostaining. Fifteen patients were classified as cases of IgG4-ROD and 23 patients as cases of non-IgG4-ROD. Two readers performed blinded analyses of MRI images. The main criterion was the presence of an IONE, defined as the infraorbital nerve diameter being greater than the optic nerve diameter in the coronal section.

Results

IONE was present in 53% (8/15) of IgG4-ROD cases whereas it was never present (0/23) in cases of non-IgG4-ROD (P < 0.0001). IONE was only present in cases where, on MRI, the inflammation of the inferior quadrant was present and in direct contact with the ION canal.

Conclusions

In European patients suffering from orbital inflammation, the presence of IONE on an MRI is a specific sign of IgG4-ROD. Recognition of this pattern may facilitate the accurate diagnosis for clinicians and allow for the adequate management and appropriate care of their patients.

Key points

? IONE on an MRI is a specific sign of IgG4-ROD. ? IONE recognition allows for a quicker diagnosis and appropriate management. ? IONE appears when inflammation is in direct contact with the ION canal.
  相似文献   
89.
90.
Intra spinal primary melanoma is a rare entity. We report a new case, atypical in relation to its primary radicular location, and to its early metastatic intradural and extra-medullary location, six months later. MRI is the more valuable examination, showing a spontaneously hyper-intense lesion on T1-weighted MR images, intense enhancement after gadolinium administration, and decreased signal on T2-weighted MR images, thus suggesting a diagnosis of melanocytic or hemorrhagic lesion. Signal abnormalities are not specific and definitive diagnosis is established after histological analysis.  相似文献   
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