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41.
Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...  相似文献   
42.

Background

Endoscopic ultrasound (EUS)-guided drainage is widely used to manage pancreatic pseudocysts. Several studies have reported the use of EUS-guided drainage for pancreatic fistula and stasis of pancreatic juice caused by stricture of the pancreatic duct after pancreatic resection.

Methods

At the authors’ hospital, 262 patients underwent surgery involving pancreatic resection from April 2005 to March 2010. In 90 of these patients (34%), a grade B or C postoperative pancreatic fistula developed that required additional treatment. The authors performed EUS-guided transmural drainage (EUS-TD) for six patients (2.1%) with a pancreatic fistula or dilation of the main pancreatic duct visible by EUS. Percutaneous drainage was provided for 18 patients (6.8%). The success rates for EUS-TD and percutaneous drainage were compared in a retrospective analysis.

Results

In all six cases, EUS-TD was performed successfully without complications. Five of the six patients were successfully treated with only one trial of EUS-TD. The final technical success rate was 100% for both EUS-TD and percutaneous drainage. Both the short- and long-term clinical success rates for EUS-TD were 100% and those for percutaneous drainage were 61.1 and 83%, respectively. The differences in these rates were not significant (short-term success, P?=?0.091 vs. long-term success, P?=?0.403). However, the time to clinical success was significantly shorter with EUS-TD (5.8?days) than with percutaneous drainage (30.4?days; P?=?0.0013) in the current series.

Conclusions

The EUS-TD approach appears to be a safe and technically feasible alternative to percutaneous drainage and may be considered as first-line therapy for pancreatic fistulas visible by EUS.  相似文献   
43.
Septal hyper-contractility is thought to be the principal cause of significant left ventricular outflow tract obstruction (LVOT) and systolic anterior motion (SAM) of the mitral valve by making the distance between the mitral valve and papillary muscle shorter. A seven-year-old patient with severe hypertrophic obstructive cardiomyopathy underwent direct interventricular septal myectomy/myotomy using the resection/crush method to modify hyper-contractility. The procedure successfully reduced the pressure gradient from 180 mmHg to 7.6 mmHg, and systolic anterior movement of the mitral leaflet disappeared. Mitral regurgitation improved from grade 2 to grade 0. Postoperative echocardiographic vector velocity imaging (VVI) study revealed a reduced twist angle, depicting attenuated ventricular contraction power from a maximum twist 17.9° to 7.9°. Perioperative VVI revealed that interventricular septal myectomy/myotomy is useful, not only in reducing LVOT obstruction, but also in reducing hyper-contractility, which increases the distance from the mitral valve to the papillary muscle and relieves SAM.  相似文献   
44.
The prognosis of patients with distant metastases of pulmonary pleomorphic carcinoma is poor. We report a case of pulmonary pleomorphic carcinoma patient who underwent surgical resection of small bowel metastasis. A 69-year-old man developed anemia secondary to melena 6 months after right upper lobectomy for pulmonary pleomorphic carcinoma and small bowel metastasis was detected endoscopically. He underwent laparoscopic ileocecal resection and has survived for 2 years after lung cancer resection without any other recurrence or metastasis.  相似文献   
45.
The recovery of all of the islets contained in a pancreas is the goal of islet isolation for transplantation. This study reveals an environment that injures the isolated islets during digestion and proposes a new model for optimal islet isolation. Islets were isolated from Wistar rat pancreases by stationary collagenase digestion while the digestion time was varied at 15, 30, 60, and 120 min. The digested pancreas and islets were analyzed histologically and adenosine nucleotides were measured. Overnight cultured islets (40 islets) were cocultured for 30 min with the supernatants obtained from pancreatic collagenase digestion at different digestion periods in order to assess the toxic environment. The peak yields of islets were obtained at 30 min of digestion. The histological study of digested pancreas showed that the exocrine cells lost their cellular integrity at 120 min of digestion, but the islet cells were left intact. Accordingly, the ATP levels of the pancreatic tissue decreased during the digestion period. The coculture experiment demonstrated that the islets cultured with the supernatants from the collagenase digestion showed digestion time-dependent disruption of the cellular integrity of islets in accordance with a rapid decrease of ATP levels in the islets. The addition of serine protease inhibitors into this coculture clearly showed protection of islets, which maintained high ATP levels in association with intact membrane integrity as assessed by AO/PI staining. Morphological deterioration of islets as well as a marked ATP decrease was evident in the entire digested pancreas as well as in islets cocultured in the supernatants from the collagenase digestion. Various factors toxic to the islets can therefore be analyzed in future experiments using this coculture model for obtaining a good yield of viable islets.  相似文献   
46.
We evaluated the neural substrates of cross-modal binding and divided attention during audio-visual speech integration using functional magnetic resonance imaging. The subjects (n = 17) were exposed to phonemically concordant or discordant auditory and visual speech stimuli. Three different matching tasks were performed: auditory-auditory (AA), visual-visual (VV) and auditory-visual (AV). Subjects were asked whether the prompted pair were congruent or not. We defined the neural substrates for the within-modal matching tasks by VV-AA and AA-VV. We defined the cross-modal area as the intersection of the loci defined by AV-AA and AV-VV. The auditory task activated the bilateral anterior superior temporal gyrus and superior temporal sulcus, the left planum temporale and left lingual gyrus. The visual task activated the bilateral middle and inferior frontal gyrus, right occipito-temporal junction, intraparietal sulcus and left cerebellum. The bilateral dorsal premotor cortex, posterior parietal cortex (including the bilateral superior parietal lobule and the left intraparietal sulcus) and right cerebellum showed more prominent activation during AV compared with AA and VV. Within these areas, the posterior parietal cortex showed more activation during concordant than discordant stimuli, and hence was related to cross-modal binding. Our results indicate a close relationship between cross-modal attentional control and cross-modal binding during speech reading.  相似文献   
47.

Purpose

To examine the usefulness of the early phase [11C]BF-227 positron emission tomography (PET) for (1) conferring additional diagnostic value by providing perfusion-like information and (2) obtaining the appropriate anatomical standardization (AS) using three-dimensional stereotactic surface projection (3D-SSP) method.

Methods

This study included 20 mild cognitive impairment (MCI), 19 Alzheimer’s disease (AD), and 17 normal cognitive (NC) subjects. Early- and late-phase BF-227 PET images were obtained 0–10 and 40–60 min after the injection, respectively. AS for late-phase BF-227 images were performed by 2 methods: (1) method A, for AS of late-phase BF-227 images using 8F-fluorodeoxyglucose (FDG) images of the same subject and (2) method B, for AS of late-phase BF-227 images using early phase BF-227 images.

Results

Method B was successfully used for AS in all cases. The Z score maps of 3D-SSP analyses of FDG PET and early phase BF-227 PET for AD and MCI groups showed a typical AD-like pattern. Regional analyses revealed that the early phase BF-227 PET showed significant differences between AD and NC, and MCI and NC.

Conclusion

The early phase BF-227 PET images showed significant abnormal findings for the AD and MCI groups. AS of late-phase BF-227 images using early phase BF-227 images were successful, and enabled appropriate 3D-SSP analyses.  相似文献   
48.
Acute type A aortic dissection in the presence of a previously repaired atherosclerotic descending thoracic aortic aneurysm is rarely reported. We experienced a patient who underwent an ascending aortic replacement with reconstruction of the aortic arch 16 months after repair of a descending thoracic aortic aneurysm. We succeeded in the redo operation with comprehensive techniques involving selective cerebral perfusion, deep hypothermia, early antegrade systemic circulation for cerebral protection, and femoro-femoral bypass with occlusion of the descending aorta for lower systemic perfusion as well as renal perfusion. The patient recovered and is doing well one year after the redo operation.  相似文献   
49.
Levels of HtrA1 protein in cartilage have been reported to elevate in joints of human osteoarthritis patients. To understand roles of HtrA1 in normal osteogenesis as well as in pathogenesis of arthritis, we examine HtrA1 expression pattern during bone and cartilage development and in articular cartilage affected by experimental arthritis. HtrA1 is not expressed in mesenchymal or cartilage condensations before initiation of ossification. When ossification begins in the condensations, the expression of HtrA1 starts in chondrocytes undergoing hypertrophic differentiation near the ossification center. Hypertrophic chondrocytes found in adult articular cartilage and epiphyseal growth plates also express HtrA1. When arthritis is induced by injection of anti-collagen antibodies and lipopolysaccharide, resting chondrocytes proceed to terminal hypertrophic differentiation and start expressing HtrA1. These data suggest that hypertrophic change induces HtrA1 expression in chondrocytes both in normal and pathological conditions. HtrA1 has been reported to inhibit TGF-beta signaling. We show that HtrA1 digests major components of cartilage, such as aggrecan, decorin, fibromodulin, and soluble type II collagen. HtrA1 may, therefore, promote degeneration of cartilage by inducing terminal hypertrophic chondrocyte differentiation and by digesting cartilage matrix though its TGF-beta inhibitory activity and protease activity, respectively. In bone, active cuboidal osteoblasts barely express HtrA1, but osteoblasts which flatten and adhere to the bone matrix and osteocytes embedded in bone are strongly positive for HtrA1 production. The bone matrix shows a high level of HtrA1 protein deposition akin to that of TGF-beta, suggesting a close functional interaction between TGF-beta and HtrA1.  相似文献   
50.
Background and aim  A retrospective analysis was performed on 32 patients with histologically confirmed xanthogranulomatous cholecystitis (XGC) and 21 patients with gallbladder carcinoma who underwent surgical treatment between 1998 and 2007. Methods  All patients underwent preoperative CT scanning. The CT features analyzed were: the presence of intramural hypoattenuated nodules or bands, mucosal line, the patterns of wall thickening and enhancement, and the presence of stones in the gallbladder. The variables of the CT findings with XGC were analyzed using multivariate logistic regression analysis. Results  Intramural hypoattenuated nodules were observed in 21 patients (65%) with XGC, but in only six patients (29%) with gallbladder carcinoma (< 0.01). The mucosal line was observed in 27 patients (84%) with XGC and in only four patients (19%) with gallbladder carcinoma (< 0.0001). Gallstones were noted in 24 patients (75%) with XGC and five patients (24%) with gallbladder carcinoma (< 0.001). There was no significant difference in the pattern of gallbladder wall thickening (diffuse or focal) and the presence of changes outside the gallbladder. Multivariate logistic regression analysis revealed from the CT features that the enhanced continuous mucosal line (= 0.0013) and the presence of gallstones (= 0.0072) were independently correlated with XGC. Conclusion  CT features of the enhanced continuous mucosal line in a thickened gallbladder wall, together with gallstones in a patient with chronic gallbladder disease, are highly suggestive of XGC. Accurate diagnosis of XGC may therefore indicate the need to select a less aggressive surgical approach.  相似文献   
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