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991.
Surgery Today - Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. A group...  相似文献   
992.
Graefe's Archive for Clinical and Experimental Ophthalmology - The aim of this study was to analyze choroidal structures in healthy subjects and patients with/without diabetic macular edema...  相似文献   
993.
Regenerative medicine approaches aiming at treating degenerating intervertebral discs, a major cause of back pain, are increasingly tested in ex‐vivo disc explant models mimicking in‐vivo conditions. For assessing the efficacy of regenerative therapies, cell viability is commonly measured requiring specific labels to stain cells. Here, we demonstrate and evaluate how cellular auto‐fluorescence can be utilized to non‐invasively assess viability in disc tissue in‐situ using label‐free two‐photon microscopy. Live and dead bovine disc cells (0% and 100% cell viability) from the nucleus pulposus were seeded into collagen gels and auto‐fluorescence was characterized. Subsequently, nucleus pulposus explants were cultured for 6 days in media with different glucose supplementation (0, 0.25, 0.5, and 1 g/L) to induce different degrees of cell death. Then, samples were split and viability was assessed using label‐free two‐photon microscopy and conventional staining. Results show that live and dead nucleus pulposus cells systematically emit auto‐fluorescent light with distinct characteristics. Cell viability values obtained with label‐free microscopy did not significantly differ from those acquired with staining. In summary, monitoring auto‐fluorescence facilitates accurate cell viability assessment in nucleus tissue requiring no additional dyes. Thus, this technique may be suitable for pre‐clinical testing of regenerative therapies in nucleus pulposus cultures. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:545–550, 2014.  相似文献   
994.

Background

Patient and graft survival after successful kidney transplantation (KT) have improved despite an increase in the number of challenging cases. Various factors have evolved during the long history of kidney transplantation.

Methods

Between 1988 and 2012, a total of 292 living donor and 56 deceased donor KTs were performed at Niigata University Hospital. Long-term patient and graft survival and changes in background during a 20-year period in a single center were retrospectively analyzed.

Results

Excellent patient survival rates of 95.1% at 20 years for living donor KT and 96.2% at 15 years for deceased donor KT were observed. Graft survival rates at 1, 5, 10, 15, and 20 years were 96.8%, 95.4%, 83.1%, 61.8%, and 56.2% in living donor KT, respectively. In contrast, graft survival rates at 1, 5, 10, and 15 years in deceased donor KT were 89.0%, 80.3%, 77.3%, and 33.8%, respectively. These survival rates have dramatically improved since 2002 (91.7% for living and 80.9% for deceased donor KT at 10 years post-transplantation). The number of elderly recipients (older than 60 years) and the percentage of grafts donated from spouses have increased. The rejection rate decreased and the cytomegalovirus antigenemia–positive rate increased during the 20-year period assessed. The percentage of pre-emptive KTs progressively increased, with graft survival in this group tending to be better than non-preemptive KTs. The causes of graft loss were chronic allograft dysfunction (54.7%), acute rejection (11.1%), and malignancies (9.4%). After living donor KT, the principal predictors of graft loss were if the recipient was younger than 30 years, if the donor was older than 50 years, and if the rejection episodes occurred after living donor KT. In contrast, the only risk factor in the case of deceased donor KT occurred after transplantation from donors who were older than 50 years.

Conclusions

A summary of the long-term outcome of KT over 20 years in a single center has been reported. Along with the changes in patient backgrounds, immunosuppressive drugs, and our knowledge of transplantation, patient and graft survival outcomes have also changed. Investigation into such outcomes during a different transplantation era is required to fully appreciate advances in KT.  相似文献   
995.
Vascular complications of distal femoral fractures are rare but can have disastrous consequences if not recognised and treated promptly. We present the case of a 55-year-old woman who developed a pseudoaneurysm of the superficial femoral artery after osteosynthesis to repair a supracondylar femoral fracture. Eight weeks after surgery, swelling of the right thigh persisted and was accompanied by severe pain. Enhanced computed tomography revealed a pseudoaneurysm in the medial aspect of the affected thigh. Open surgical repair was performed by direct arterial suture. Although the true aetiology of the development of the pseudoaneurysm is unknown, a bony fragment from the reduction manoeuvre may have damaged the adventitia of the superficial femoral artery. In cases of continuous thigh swelling after osteosynthesis to repair a supracondylar femoral fracture, a diagnosis of pseudoaneurysm should be considered and treatment should be initiated immediately.  相似文献   
996.
Pancreatic graft thrombosis is the primary cause of nonimmunologic graft loss, with an incidence ranging from 5% to 15%. Therefore, developing a screening test to detect graft thrombosis after pancreatic transplantation is important. We created a screening test to assess graft thrombosis after pancreatic transplantation using contrast-enhanced ultrasonography (CEUS) with Sonazoid in addition to Doppler ultrasonography. A total of seven patients were examined using CEUS after undergoing pancreatic transplantation. All patients were observed to have a clear blood flow from the horizontal region to the peripheral region of the splenic vein in the pancreatic graft, and only one of the seven patients exhibited a blood flow in the horizontal portion of the splenic vein on Doppler ultrasonography performed immediately after pancreatic transplantation. Results from CEUS with Sonazoid showed the blood flow in the splenic vein and parenchyma of the pancreatic graft in detail, despite the slow and lateral blood flow in the splenic vein of the pancreatic graft immediately after transplantation.  相似文献   
997.

Study design

Imaging study of thoracic spine.

Objective

The purpose of this study was to investigate dynamic alignment and range of motion (ROM) at all segmental levels of thoracic spine.

Summary of background data

Thoracic spine is considered to have restricted ROM because of restriction by the rib cage. However, angular movements of thoracic spine can induce thoracic compressive myelopathy in some patients. Although few previous studies have reported segmental ROM with regard to sagittal plane, these were based on cadaver specimens. No study has reported normal functional ROM of thoracic spine.

Methods

Fifty patients with cervical or lumbar spinal disease but neither thoracic spinal disease nor compression fracture were enrolled prospectively in this study (34 males, 16 females; mean age 55.4 ± 14.7 years; range 27–81 years). After preoperative myelography, multidetector-row computed tomography scanning was performed at passive maximum flexion and extension position. Total and segmental thoracic kyphotic angles were measured and ROM calculated.

Results

Total kyphotic angle (T1/L1) was 40.2° ± 11.4° and 8.5° ± 12.8° in flexion and extension, respectively (P < 0.0001). The apex of the kyphotic angle was at T6/7 in flexion. Total ROM (T1/L1) was 31.7° ± 11.3°. Segmental ROM decreased from T1/2 to T4/5 but increased gradually from T4/5 to T12/L1. Maximum ROM was at T12/L1 (4.2° ± 2.1°) and minimum at T4/5 (0.9° ± 3.0°).

Conclusions

Thoracic spine showed ROM in sagittal plane, despite being considered a stable region. These findings offer useful information in the diagnosis and selection of surgical intervention in thoracic spinal disease.  相似文献   
998.

Purpose

To evaluate the anatomical variations in the middle hepatic vein tributaries (V5/V8) for determining the reconstruction strategy in right lobe living donor liver transplantation (LDLT).

Methods

The V5/V8 variations were examined in 268 patients and were classified into three and two types, respectively. The reconstruction rate (RR), patency rate (PR) and clinical outcomes were retrospectively evaluated in 46 right lobe LDLT cases.

Results

In terms of V5 variations, the RR and PR were significantly higher for type 2 than type 3 (82.6 vs. 44.4 % and 73.7 vs. 25.0 %, respectively). The alanine aminotransferase level on postoperative day (POD) 5 in the V5 patent group was significantly lower than in the occluded group (123 vs. 191 IU/dL). Regarding V8 variations, the RR and PR were significantly higher for type 1 than type 2 (44.4 vs. 17.6 % and 75.0 vs. 33.3 %, respectively). The aspartate aminotransferase level on POD 3 was significantly lower in the V8 patent group than in the occluded group (50 vs. 121 IU/dL).

Conclusion

For right lobe grafts with single large V5 (type 2) or V8 (type 1) variations, reconstruction is necessary. Our new classification of the MHV tributaries is useful for determining the reconstruction strategy to use in right lobe LDLT.  相似文献   
999.
Esophageal cancer is frequently associated with squamous cell carcinoma in the head and neck. Both cigarette smoking and alcohol consumption are risk factors for multiple cancers of the head and neck, as well as the esophagus. Routine screening and close follow-up for second cancers are important in patients with esophageal cancer or head and neck cancer. For this purpose, endoscopy with Lugol’s staining, as well as narrow-band imaging combined with magnifying endoscopy, is a powerful tool for the early detection of esophageal cancer. Multimodal therapy is essential for patients with double cancers. When considering surgical treatment, the curability of both cancers must be carefully evaluated. If both tumors are potentially curable, each lesion should be treated individually. In patients with metachronous double cancers, the prior treatment of the first primary carcinoma often affects the treatment of the second cancer. Close cooperation among medical staff members is essential for complicated surgeries for double cancers. Techniques that are appropriate for each case must be adopted, such as careful dissection, staged operations, muscular flaps and microvascular anastomosis.  相似文献   
1000.
It is suggested that masticatory dysfunction affects the central nervous system; however, the underlying mechanism remains unknown. Brain‐derived neurotrophic factor (BDNF) and its receptor, TrkB, are known to play important roles in memory and learning. In this study, we examined the effects of mastication on memory, the expression levels of BDNF and TrkB, and the number of neurons in the hippocampus of mice. Male C57 BL/6J mice (3 weeks old) were randomly divided into the control group (N = 7) fed chow pellets and the experimental group (N = 7) fed a liquid diet, which reduces mastication during eating. At 14 weeks of age, we performed a passive avoidance test and found that memory and learning ability were impaired in the experimental group compared with the control group. After the behavioral experiment, brains were harvested and analyzed morphologically and biochemically. In the hippocampus of the experimental group, the expression levels of BDNF were significantly higher, whereas those of TrkB were lower than those of the control group. In the cerebral cortex, these levels remained unchanged between the two groups. The ratio of phospho‐p44/42 ERK/pan ERK, a downstream molecule of BDNF/TrkB signaling, in the experimental group was significantly lower than that of the control group in the cortex and hippocampus. The number of pyramidal neurons in the hippocampus was lower in the experimental group than in the control group. These findings suggest that reduced mastication induced by a liquid diet in early childhood may impair memory and learning ability, accompanied by neuronal loss in the hippocampus. © 2014 Wiley Periodicals, Inc.  相似文献   
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