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81.
To identify mitochondrial haplogroups that confer resistance against or susceptibility to metabolic syndrome, we performed a large-scale association study on 1,337 unrelated Japanese individuals, including 871 subjects with metabolic syndrome and 466 control subjects. Metabolic syndrome was diagnosed according to modified National Cholesterol Education Program Adult Treatment Panel III guidelines, using the cutoff point for obesity as a BMI of >/=25 kg/m(2) instead of waist circumference. The genotypes for 25 polymorphisms in the coding region of the mitochondrial genome were determined, and the haplotypes were classified into 10 major haplogroups, i.e., F, B, A, N9a, M7a, M7b, G1, G2, D5, and D4. Multivariate logistic regression analysis revealed that the haplogroup N9a was significantly associated with resistance against metabolic syndrome in women with an odds ratio (OR) of 0.21 (95% CI 0.07-0.58, P = 0.0042). Women with haplogroups G1 and D5 tended to be resistant against metabolic syndrome with an OR of 0.22 (0.06-0.68, P = 0.0129) for G1 and with an OR of 0.32 (0.10-0.96, P = 0.0469) for D5, respectively. These results indicate that mitochondrial haplogroup N9a may be a protective factor against metabolic syndrome in Japanese women.  相似文献   
82.
83.
BACKGROUND: To assess tissue characterization of oral tongue cancer and prediction of subclinical cervical lymph node metastasis, we investigated whether intraoral ultrasonography could be used in conjunction with a computer-aided diagnosis (CAD) system. METHODS: The study population comprised 109 patients with presurgical, clinical T1N0 or T2N0 oral tongue squamous cell carcinoma who underwent partial glossectomy. All the patients were examined by preoperative intraoral and postoperative ex vivo ultrasonography. To evaluate the ultrasonic images quantitatively, ultrasonographic parameters from tumor contour features were computed by using the proposed CAD system. The imaging results were correlated with histopathologic findings. RESULTS: Oral tongue cancer was clearly identified in all patients by intraoral ultrasonography. Ultrasonic images of oral tongue cancer reflected the histopathologic structures. Subclinical cervical lymph node metastasis was predicted by intraoral ultrasonography. In a logistic regression analysis using the proposed CAD system, the diagnostic sensitivity, specificity, and accuracy for prediction of subclinical lymph node metastasis were 87.2%, 84.3%, and 85.3%, respectively. CONCLUSIONS: Intraoral ultrasonography in conjunction with the proposed CAD system allows tissue characterization and prediction of subclinical cervical lymph node metastasis.  相似文献   
84.
OBJECTIVE: We compared the surgical outcome of anterior decompression with spinal fusion (ASF) with the surgical outcome of laminoplasty for patients with cervical myelopathy due to ossification of the posterior longitudinal ligament. METHODS: The study group comprised 19 ASF patients (A-group) and 40 laminoplasty patients (P-group) treated from 1993 to 2002 with 1 year or longer follow-up. The Japanese Orthopedic Association scoring system was used to evaluate cervical myelopathy, and the recovery rate calculated 1 year after surgery. RESULTS: The mean recovery rate was 68.4% in the A-group and 52.5% in the P-group (P<0.05). Fifteen patients had a recovery rate less than 40%: 2 in the A-group and 13 in the P-group. One P-group patient and none of the A-group patients developed postoperative aggravation of their neurologic status. The P-group was divided into 2 subgroups: a good outcome group comprising patients whose recovery rate was 40% or higher (n=27) and a poor outcome group comprising patients whose recovery rate was less than 40% (n=13). The mean age at surgery was 59.9 years in the good outcome group and 68.0 years in the poor outcome group (P<0.05). The mean range of intervertebral mobility at maximum cord compression level before surgery was 6.9 degrees in the good outcome group and 10 degrees in the poor outcome group (P<0.05). CONCLUSIONS: These results demonstrated that the surgical outcome of ASF was superior to the surgical outcome of laminoplasty. Elderly patients treated with laminoplasty showed an especially poor surgical outcome. We suggest that hypermobility of vertebrae at the cord compression level is a risk factor for poor surgical outcome after laminoplasty. Based on these results, we recommend that ASF should be the first choice of treatment for patients with significant ossification of the posterior longitudinal ligament and a hypermobile cervical spine. When laminoplasty is used for such cases, the addition of posterior instrumented fusion would be desirable for stabilizing the spine and decreasing damage to the spinal cord.  相似文献   
85.
Undescended testis is one of the most common congenital anomalies requiring surgery. The guideline for the treatment of undescended testis was published by Japanese Society of Pediatric Urology in 2005. However, the management of undescended testis has been still controversial, particularly in case of impalpable testis including abdominal testis. In this article, we review our experience and published reports of orchiopexy for undescended testis and emphasize that the anatomical condition of undescended testis should be applied to individualized surgical treatment.  相似文献   
86.
BACKGROUND: In vitro, the extracellular signal-regulated kinase (ERK) is an intracellular convergence point of multiple stimuli, which affect the cell cycle. However, the role of ERK in cell cycle regulation in vivo is unknown. METHODS: To address this issue, ERK activity was blocked both in vitro in mesangial cells (MC) and in vivo in experimental glomerulonephritis (GN) by a pharmacological inhibitor (U0126) of the ERK-activating kinase. RESULTS: In stimulated MC, inhibition of ERK reduced cyclin-dependent kinase 2 (CDK2) phosphorylation, CDK2 activity and cyclin E/A expression, whereas downregulation of CDK inhibitor p27(Kip1) expression was inhibited. In vivo, U0126 was given to rats in the acute phase of anti-Thy 1.1 GN. We previously showed that glomerular cell proliferation was reduced by 67% upon treatment with the inhibitor compared to nephritic controls. Now, we detected a significant increase in renal CDK2-activity/phosphorylation in the nephritic controls, that was significantly and dose-dependently reduced by ERK inhibition. CDK2 activation was accompanied by an increase in renal expression of cyclins E/A and the enhanced binding of these cyclins to CDK2 in the nephritic controls. These changes were blunted by U0126 treatment. Finally, we noted an increased expression and CDK2-binding of p27(KIP1) protein in the nephritic controls which was decreased in U0126 treated rats. CONCLUSIONS: Our observations provide the first evidence that ERK is an intracellular regulator of renal CDK2 activity in vivo in a glomerulonephritis model.  相似文献   
87.
OBJECTIVE: It is controversial whether a systematic mediastinal lymph node dissection (MLND) needs to be performed in all patients with stage I lung cancer. The present study was done to examine the new sentinel lymph nodes hypothesis based on the lobe of the primary tumor. METHODS: In our first study, the lymph node (LN) metastases were assessed in 291 stage I non-small cell lung cancer (NSCLC) patients who had a major lung resection with a systematic mediastinal lymph node dissection. We evaluated the validity of using our new sentinel lymph nodes method based on the lobe of the primary tumor as follows: the pretracheal (#3), tracheobronchial (#4), and hilar nodes (#10) for right upper lobe tumors; #4, subcarinal (#7), and #10 for middle lobe tumors; the subaortic (#5), paraaortic (#6), and #10 for left upper lobe tumors; and the #7, #10, and interlobar nodes (#11) for tumors in either lower lobes. In the second study, we performed a lobectomy with new sentinel node sampling in 64 patients with preoperative complications. If all of the sampling nodes showed no metastases on frozen section diagnosis, systematic node dissections were not performed. RESULTS: Six of 291 patients in the first study had skip metastases that did not involve the new sentinel nodes; 5 of the 6 patients had macroscopic pleural invasion. Thus, we defined pleural invasion as an exclusion criterion for the second study. In the second study, the median follow-up time was 39 months. Metastatic lymph nodes were detected in 11 of 64 patients. Fifty-three patients (83%) had no metastasis in the sampled nodes, and, therefore, a mediastinal lymph node dissection was not done. The morbidity rate in the sampling group was 36%, and there was no mortality. In the sampling group, local recurrences were observed in two patients, distant metastases in eight, and carcinomatous pleuritis in one; the overall 5-year survival rate was 82%. CONCLUSIONS: We found that it is possible to perform a less invasive lymphadenectomy for patients with stage I lung cancer using intra-operative sampling of new sentinel lymph nodes.  相似文献   
88.
We report two cases of atraumatic iliopsoas hematoma. First patient was a 76-year-old man admitted to our hospital from appetite loss. Blood transfusion did not improve his anemia. Five days after admission, suddenly he went into shock. CT scan revealed ileopsoas hematoma. He died from hemorrhagic shock in spite of conservative therapy. Second patient was a 70-year-old man admitted because of acute heart failure. Continuous hemodiafiltration was required to relieve anuria. The next day, he developed left leg and hip pain. CT scan revealed ileopsoas hematoma and he received CT guided aspiration drainage for decompression, but almost 7 days were needed to achieve successful pain control. In a case of iliopsoas hematoma, early diagnosis and adequate choise of therapy are necessary to improve prognosis of patients.  相似文献   
89.
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques.  相似文献   
90.

Background

Mesenchymal stem cells (MSCs) are being developed as a new clinically relevant stem cell type to be recruited into and to repair injured tissue. A number of studies have focused on the therapeutic potential of MSCs by virtue of their immunomodulatory properties. Systemically administered MSCs can also migrate to sites of malignancies. Because of this latter phenomenon, we transfected human MSCs to secrete anti–high mobility group box (HMGB) 1 proteins. They were then injected into mice bearing human colon cancer to evaluate their efficacy as an antineoplastic agent.

Materials and methods

The ABOX gene was used in this model, which encodes part of the HMGB1 protein and acts as an HMGB1 antagonist. It was cotransduced by electroporation with a FLAG-tag to visualize the secreted ABOX protein, levels of which in supernatants from cultured transfected MSCs were quantified by immunofluorescence imaging using an anti-FLAG antibody. Antiangiogenic effects were evaluated in vitro using a novel optical assay device for the quantitative measurement of cellular chemotaxis assessing the velocity and direction of endothelial cell movement stimulated by supernatant from tumor cells. We found that ABOX proteins released from transfected MSCs suppressed migration in this assay. Finally, MSCs were injected subcutaneously into Nonobese diabetic/severe combined immunodeficiency mice bearing human colon cancer from a cell line, which secreted large amounts of HMGB1. Ten days after MSC injection, mice were sacrificed and tumors evaluated by immunohistochemistry.

Results

From 12 ho through 7 d after gene transfection, ABOX proteins secreted from MSCs could be detected by immunofluorescence and enzyme-linked immunosorbent assay. Quantitative measurement of cellular chemotaxis demonstrated that ABOX proteins secreted from transfected MSCs decreased the velocity and interfered with the direction of movement of vascular endothelial cells. Moreover, in an in vivo human colon cancer xenograft model, injection of anti-HMGB1–transfected MSCs resulted in a decreased tumor volume due to the antiangiogenic properties of the secreted ABOX proteins.

Conclusions

MSC modified to secrete HMGB1 antagonist proteins have therapeutic antineoplastic potential. These findings may contribute to future novel targeting strategies using autologous bone marrow–derived cells as gene delivery vectors.  相似文献   
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