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11.
12.

Objective

The purpose of this nonrandomized retrospective study was to report our new procedures using polyethylene glycolic acid (PGA) felt with fibrin sealant to prevent severe pancreatic fistula in patients undergoing pancreatic surgery.

Methods

From 2000 to 2008, 54 and 63 patients underwent pancreaticoduodenectomy (PD) and distal pancreatectomy (DP), respectively. Of those patients, we applied PGA felt with fibrin sealant to 18 PD patients and 26 DP patients. In PD patients, the PGA felt was wrapped around the pancreatic suture site, while in DP patients, the PGA felt was wrapped around the predictive division site. The pancreaticojejunostomy site in PD patients and the cut stump in DP patients were coated with fibrin sealant. We compared the occurrence rates for severe postoperative pancreatic fistula (POPF) that occurred after PD or DP both with and without our new procedures.

Results

Before introduction of our procedures, severe POPF developed in 14 of 36 PD patients (39%) and 10 of 37 DP patients (27%). In contrast, after introduction of our procedures, the incidence of POPF was only one in both of 18 PD (6%; P?=?0.016) and 26 DP (4%; P?=?0.017) patients.

Conclusion

In summary, our procedure using PGA felt with fibrin sealant may reduce the risk of severe POPF.  相似文献   
13.
Degradation of Meckel's cartilage in the middle portion is accompanied by hypertrophy and death of chondrocytes, calcification of the cartilaginous matrix, and chondroclastic resorption. We hypothesize that the gelatinolytic activity of matrix metalloproteinases (MMPs) largely contributes to the degradation of extracellular matrix (ECM) in the process. The activity in Meckel's cartilage of mouse mandibular arches at embryonic days 14-16 (E14-E16) was examined by a combination of in situ zymography (ISZ), using quenched fluorescent dye-labeled gelatin as a substrate, with CTT (a selective inhibitor of MMP-2 and -9) or with EDTA (a general MMP inhibitor). On E14 and E15, ISZ showed fluorescence in the perichondrium, in the intercellular septa between chondrocytes, and in the nucleus of chondrocytes. CTT attenuated fluorescence, and EDTA eliminated it. On E16, calcified cartilaginous matrix showed intense fluorescence, and dot-like fluorescence was observed in as-yet uncalcified intercellular septa, even after CTT treatment. EDTA inhibited fluorescence, but unexpectedly intense fluorescence was found in the cytoplasm of hypertrophic chondrocytes facing the resorption front. MMP-2, -9, and -13 immunoreactivity was detected in the perichondrium and chondrocytes of Meckel's cartilage. These findings suggest that MMPs and other proteinases capable of degrading gelatin play an integral role in the development, calcification, and resorption of Meckel's cartilage through ECM reconstitution.  相似文献   
14.
Conclusion: The maximum standardized uptake value (SUVmax) of early oral squamous cell carcinoma (OSCC) may have a role as an imaging biomarker for assessment of malignant potential, including cell metabolism and angiogenesis. Objective: The usefulness of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) has been proven in various cancers, including OSCC. Moreover, in several carcinomas, the SUVmax of the tumor has been shown to correlate with the histological type, tumor stage, differentiation, and prognosis. Here, we investigated whether the SUVmax of early OSCC was associated with the biological features. Methods: Twenty-seven patients with newly diagnosed early OSCC who underwent preoperative FDG-PET and curative surgical resection were included in this study. Tumor sections were stained by immunohistochemistry for glucose transporter 1 (GLUT1), L-type amino acid transporter 1 (LAT1), CD98, microvessels (CD34), cell proliferation marker (Ki-67), and cell cycle regulator (p53). The correlation between SUVmax and clinicopathological findings or the expression level of these molecules was analyzed. Results: SUVmax of primary OSCC was significantly higher in patients with T2 stage. Moreover, patients whose tumors showed vascular invasion had a tendency to show higher SUVmax. A significant correlation was observed between SUVmax and the expression of LAT1 or microvessel density.  相似文献   
15.

Background

The Golgi apparatus is at a crossroads between anterograde and retrograde trafficking. It exhibits a twisted ribbon-like network in the juxtanuclear region of vertebrate cells. Vesicle-associated membrane protein 4 (VAMP4) is a unique v-SNARE expressed exclusively in trans-Golgi networks (TGN), where it regulates retrograde trafficking from the early endosome to the TGN with its cognate SNARE partners Syntaxin 6, Syntaxin 16, and Vti1a.

Highlight

To examine whether VAMP4 plays a role in maintaining the Golgi ribbon structure, we depleted VAMP4 expression using a small interfering RNA. Depletion of VAMP4 led to fragmentation of the Golgi ribbon in HeLa cells. Immunohistochemical analysis showed that, in the absence of VAMP4, although the Golgi stack length was shortened, Golgi stacking was normal. Furthermore, depletion of the cognate SNARE partners of VAMP4 also disrupted the Golgi ribbon structure. Microscopy-based analyses showed that Golgi fragmentation did not impair anterograde traffic.

Conclusion

Our findings suggest that VAMP4 and its cognate SNAREs are required for maintaining the Golgi ribbon structure by balancing membrane transport between the endosome and TGN.  相似文献   
16.
OBJECTIVE: Previous studies indicate that hypertrophic chondrocytes can transdifferentiate or dedifferentiate and redifferentiate into bone cells during the endochondral bone formation. Mandibular condyle in aged c-src-deficient mice has incremental line-like striations consisting of cartilaginous and non-cartilaginous layers, and the former contains intact hypertrophic chondrocytes in uneroded lacunae. The purpose of this study is to determine the phenotype changes of uneroded hypertrophic chondrocytes. DESIGN: Immunohistochemical and ultrastructural examinations of the pericellular matrix of hypertrophic chondrocytes in the upper, middle, and lower regions of the mandibular condyle were conducted in aged c-src-deficient mice, using several antibodies of cartilage/bone marker proteins. RESULTS: Co-localisation of aggrecan, type I collagen, and dentin matrix protein-1 (DMP-1) or matrix extracellular phosphoprotein (MEPE) was detected in the pericellular matrix of the middle region. Ultrastructurally, granular substances in the pericellular matrix of the middle region were the remains of upper region chondrocytes, which were mixed with thick collagen fibrils. In the lower region, the width of the pericellular matrix and the amount of collagen fibrils were increased. Versican, type I collagen, DMP-1, and MEPE were detected in the osteocyte lacunae. Additionally, DMP-1 and MEPE were detected in the pericellular matrix of uneroded hypertrophic chondrocytes located in the lower, peripheral region of the mandibular condyle in younger c-src-deficient mice, but not in the aged wild-type mice. CONCLUSIONS: These results indicate that long-term survived, uneroded hypertrophic chondrocytes, at least in a part, acquire osteocytic characteristics.  相似文献   
17.
Collagenous Alzheimer amyloid plaque component (CLAC) is a unique non-Abeta amyloid component of senile plaques (SP) derived from a transmembrane collagen termed CLAC-precursor. Here we characterize the chronological and spatial relationship of CLAC with other features of SP amyloid in the brains of patients with Alzheimer's disease (AD), Down syndrome (DS), and of PSAPP transgenic mice. In AD and DS cerebral cortex, CLAC invariably colocalized with Abeta42 but often lacked Abeta40- or thioflavin S (thioS)-reactivities. Immunoelectron microscopy of CLAC-positive SP showed labeling of fibrils that are more loosely dispersed compared to typical amyloid fibrils in CLAC-negative SP. In DS cerebral cortex, diffuse plaques in young patients were negative for CLAC, whereas a subset of SP became CLAC-positive in patients aged 35 to 50 years, before the appearance of Abeta40. In DS cases over 50 years of age, Abeta40-positive SP dramatically increased, whereas CLAC burden remained at a constant level. In PSAPP transgenic mice, CLAC was positive in the diffuse Abeta deposits surrounding huge-cored plaques. Thus, CLAC and Abeta40 or thioS exhibit mostly separate distribution patterns in SP, suggesting that CLAC is a relatively early component of SP in human brains that may have inhibitory effects against the maturation of SP into beta-sheet-rich amyloid deposits.  相似文献   
18.
An 87-year-old man was found loss of consciousness after falling. He was found in a state of shock. Computed tomography showed rupture of aneurysm of the ascending aorta and aortic arch with acute aortic dissection. Echocardiography revealed aortic valve regurgitation and cardiac tamponade. As the result of emergency operation, a large hematoma in the mediastinum and pleural cavity as well as massive serous pericardial effusion were found. The dissection was seen in aneurysm of the ascending aorta and aortic arch with an intimal tear located in the aortic arch. After aortic valve replacement was performed, the ascending aorta and aortic arch were replaced, and reconstruction of 3 cervical vessel branches was performed under deep hypothermic circulatory arrest with selective cerebral perfusion. Despite the complex clinical state and serious condition in the elderly patient, emergency surgery saved the life of the patient without complications.  相似文献   
19.
The interpretation of conventional radiographic views for sinusitis in children has given rise to considerable controversy. Thirty-three children (66 sides of sinuses) aged from 4 to 15 years who were suspected of having chronic sinusitis were studied to determine the accuracy of conventional X-ray examination, comparing the results with those of CT. Coronal CT was taken after conventional X-ray examination (Waters and occipito-frontal views), and the time interval between these two examinations was 0 to 14 days (average 5.1 days). The rate of correspondence in diagnosis of sinus pathology between conventional X-ray views and CT was 74.3% in the maxillary sinus and 40.9% in the ethmoid. The rate of overestimation with conventional X-ray views was 24.2% in the maxillary sinus and 56.1% in the ethmoid, while that of underestimation was 1.5% and 3.0% in the maxillary and the ethmoid sinus respectively. The incidence of false positives according to conventional X-ray views was 8.0% in the maxillary sinus and 33.3% in the ethmoid. Our results indicate that Waters view is sufficient to diagnose maxillary sinus pathology in children. However, additional radiologic examinations, such as CT, are necessary in investigating the pathologic conditions of the ethmoid sinus, since diagnostic significance of occipito-frontal view for ethmoid pathology is doubtful in children. A routine preoperative CT is recommended, which allows a detailed evaluation of pathologic changes and anatomical relations of the ethmoid before embarking a surgical intervention for the ethmoid sinus in children.  相似文献   
20.
Many publications have repeatedly indicated that there seems to be a correlation between neoplastic disease and certain types of psychological situations. However, such studies subjected malignant tumors in head and neck region are scanty so far. We applied Cornell Medical Index Health Questionnaire (CMI) and Maudsley Personality Inventory (MPI) to collect medical and psychiatric data from 86 patients (56 males and 30 females) with head and neck malignant tumors and 115 control patients (73 males and 42 females) with head and neck diseases other than malignant tumors. Analysis of CMI data using Diagnostic Sheet, Fukamachi's method and Modification of Abe's method, and analysis of each of Extroversion-Introversion scale scores, Neuroticism scale scores and Lie scale scores of MPI led the following conclusion. 1) Both male and female patients with head and neck malignant tumors showed to be more depressive than their control patients were. Especially, between the two patient groups in males, there was a statistically significant (p less than 0.05) difference. 2) Regarding neurosis, autonomic nerve dysfunctioning and extroversion-introversion, none of these factors seemed to be related with the morbidity of head and neck malignant tumors. Further exploration of this issue, with a special attention to the relationship between depression and head and neck malignancy should be conducted, if possibly, from a prospective point of view.  相似文献   
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