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111.
M Nazarea  F Okajima  K Sho  K Inoue  Y Kondo 《Endocrinology》1989,125(1):100-108
We quantified the TSH-induced morphological change in FRTL-5 thyroid cells according to a morphological index corresponding to the mean cell area measured from microscopic photographs. Within 15 min, TSH induced, at 10 pM and higher concentrations, a decrease in morphological index together with a rise in cAMP levels in a TSH dose-dependent manner. Forskolin, 3-isobutyl-1-methylxanthine, and RO 20-1724, the latter two being phosphodiesterase inhibitors, mimicked these TSH effects, indicating that the rise in cAMP levels is responsible for the TSH effect. Extracellular ATP and its derivatives, known as purinergic receptor agonists, decreased cAMP levels and caused a complete reversal of the TSH morphological effect. Prior exposure of the cells to islet-activating protein (pertussis toxin), the depletion of extracellular Ca2+, or the addition of low doses of protein kinase-C inhibitors completely abolished the inhibitory action of ATP on the TSH effect, whereas phorbol 12-myristate 13-acetate, which activates protein kinase-C, mimicked the ATP action to some extent. Thus, although the TSH-induced change in cell morphology seems to be dependent on cAMP levels, the inhibition of TSH action by ATP seems to be mediated by at least two signal transduction pathways involving islet-activating protein substrate G-proteins: one inhibiting adenylate cyclase and the other involving Ca2+ and protein kinase-C.  相似文献   
112.
An autopsy case of granulocyte colony-stimulating factor (G-CSF)- and interleukin-6 (IL-6)-producing diffuse deciduoid peritoneal mesothelioma is reported. The patient was a 70-year-old man with abdominal distension and weight loss in the year prior to his death. Laboratory data suggested severe inflammation with marked leukocytosis, thrombocytosis and elevated serum levels of C-reactive protein, G-CSF and IL-6. Imaging studies showed an expansive mass occupying the entire abdomen and pelvic cavity. Histological diagnosis of tissue taken by needle biopsy was difficult due to the unusual sarcomatoid-appearance of the tumor. In addition, there was severe infiltration of numerous neutrophilic leukocytes. An autopsy revealed that the diffuse peritoneal tumor had a fresh fishmeat-like appearance with focal mucinous degeneration and entirely encased the abdominal organs. Histological examination showed a sheet-like proliferation of tumor cells with large ovoid or polygonal cytoplasm, large atypical nuclei and obvious nucleoli. The tumor cells showed abundant glycogen and hyaluronic acid, and were immunoreactive to cytokeratin, calretinin, epithelial membrane antigen (EMA), CA-125, and focally to vimentin. The tumor cells were immunoreactive to G-CSF and IL-6. Electron microscopy revealed long, slender microvilli on the tumor cell surface. This tumor was diagnosed as a G-CSF- and IL-6-producing, diffuse deciduoid mesothelioma. We report this case with special reference to the differential diagnosis of deciduoid peritoneal mesothelioma with paraneoplastic syndrome.  相似文献   
113.
Journal of Artificial Organs - A major concern in the clinical application of cell therapy is the manufacturing cost of cell products, which mainly depends on quality control. The mycoplasma test,...  相似文献   
114.
Radiofrequency ablation has been applied to treat hepatocellular carcinoma, with favorable therapeutic outcomes. Nevertheless, practitioners have approached radiofrequency ablation with some reluctance due to the difficulty of identifying isoechoic tumors and recurrent tumors. The aim of the present study is to investigate the efficacy of Real-time Virtual Sonography to treat hepatocellular carcinoma difficult to detect by conventional ultrasonography. Real-time Virtual Sonography is a system generating multiplanar reconstruction images in real-time using the Hitachi medico EUB-8500 equipped with a probe. The system included following components: 1) digital imaging and communications in medicine (DICOM) data from dynamic CT, 2) a magnetic field generator to match the multiplanar reconstruction image on the monitor and the actual ultrasonography image, 3) the cross section with the tumor displayed as a multiplanar reconstruction image. Total twenty-five nodules of twenty-one patients underwent radiofrequency ablation monitored by Real-time Virtual Sonography. All nodules difficult to detect via conventional ultrasonography were clearly visualized in real-time. The average nodule diameter was 2.4 +/- 1.6 cm, and punctures and coagulation were performed an average of 2.2 and 3 times per session. Dynamic CT after session confirmed effective coagulation of each nodule. In conclusion, this study demonstrates that the present system is capable of effectively and accurately treating tumors difficult to detect by conventional ultrasonography.  相似文献   
115.

Background

Balloon kyphoplasty or vertebroplasty is widely performed as a surgical intervention for osteoporotic vertebral fracture (OVF) and the effects have been investigated in many previous studies. However, the influence of the timing of the procedure on patient outcomes has not been studied formally. The purpose of this study was to investigate differences in the surgical outcomes of OVFs according to the timing of balloon kyphoplasty.

Methods

This was a multicenter cohort study. Participants comprised 72 consecutive patients who underwent balloon kyphoplasty between January 2012 and January 2016. Patients were analyzed in two groups according to the timing of kyphoplasty after onset (Early group: ≤2 months; Late group: >2 months). Follow-up continued for more than 6 months.

Results

A total of 72 patients were effectively analyzed. Of these, 27 (38%) patients underwent kyphoplasty within 2 months after symptom onset. The Late group showed greater angular motion of fractured vertebrae (p = 0.005) and compression of anterior vertebral height (p = 0.001) before surgery. Final outcomes adjusted for age and preoperative outcome showed lower visual analog scale (VAS) scores for low back pain in the Early group than in the Late group (19.9 vs. 30.4, p = 0.049). Final relative anterior vertebral height and kyphotic angle were more preserved in the Early group than in the Late group (p = 0.002 and p = 0.020, respectively), although absolute differences were not significant.

Conclusions

Vertebral height and kyphotic angle before and after balloon kyphoplasty were greater in patients who underwent kyphoplasty within 2 months after onset, and the VAS score for low back pain at final follow-up was better. Our results support kyphoplasty within 2 months.  相似文献   
116.
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118.

Background

It is unclear whether anatomic resection achieves better outcomes than nonanatomic resection in patients with hepatocellular carcinoma. This study aimed to compare the outcomes of anatomic resection and nonanatomic resection for hepatocellular carcinoma located on the liver surface via one-to-one propensity score-matching analysis.

Methods

Data from all consecutive patients who underwent liver resection for primary solitary hepatocellular carcinoma at Nara Medical University Hospital, Japan, January 2007– December 2015 were retrieved. Superficial hepatocellular carcinomas were defined as hepatocellular carcinoma that extended to a depth of?<?3?cm from the liver surface and measured?<?5?cm in diameter. The prognoses of the patients with superficial hepatocellular carcinoma who underwent anatomic resection and nonanatomic resection were compared.

Results

In this study 23 patients with superficial hepatocellular carcinoma underwent anatomic resection and 70 patients who underwent nonanatomic resection. The recurrence-free survival rate of the patients who underwent anatomic resection was better than that of the patients who underwent nonanatomic resection (P?=?.006), while no such difference was observed for nonsuperficial hepatocellular carcinoma. After the propensity score-matching procedure, the resected liver volume and operation time were the only background or clinical characteristics to exhibit significant differences between the anatomic resection (n?=?20) and nonanatomic resection groups (n?=?20). The recurrence-free survivial rate of the patients who underwent anatomic resection was significantly than that of the patients that underwent nonanatomic resections (P?=?.030), but overall survival did not differ significantly between the groups (P?=?.182).

Conclusion

Anatomic resection decreases the risk of tumor recurrence and improves recurrence-free survival compared with nonanatomic resection in patients with superficial hepatocellular carcinoma.  相似文献   
119.
Background: Acoustic radiation force impulse (ARFI) is a new technology integrated into conventional B‐mode ultrasonography. ARFI is used to evaluate tissue stiffness in several organs, but this method has not been applied for liver fibrosis. Aim: The aim of this study was to determine whether ARFI elastography is useful for the evaluation of liver fibrosis. Methods: This study enrolled 55 consecutive patients with chronic liver disease who underwent a liver biopsy for histological assessment of liver fibrosis by the Metavir scoring system. Liver stiffness of the 55 patients and 25 healthy volunteers was evaluated by ARFI elastography and was expressed as the shear wave velocity. Cut‐off values were determined using receiver‐operating characteristic (ROC) curves. Results: Histological liver fibrosis was evaluated by Metavir scoring; F0: six cases, F1: 14 cases, F2: nine cases, F3: nine cases and F4: 17 cases. Liver stiffness determined by ARFI elastography was correlated with histological liver fibrosis (P<0.0001). The areas under the ROC curves were 0.94 (95% confidence intervals, 0.87–0.99) for F2–F4, 0.94 (0.88–0.99) for F3–F4 and 0.96 (0.91–1.01) for F4. The cut‐off values of the shear wave velocity were as follows: >1.34 m/s for F2–F4 (sensitivity 91.4%, specificity 80%); >1.44 m/s for F3–F4 (sensitivity 96.2%, specificity 79.3%); and >1.80 m/s for F4 (sensitivity 94.1%, specificity 86.8%). Conclusions: Ultrasonic ARFI elastography is a novel, non‐invasive and reliable method for the assessment of liver fibrosis in patients with chronic liver disease.  相似文献   
120.
The formation of dihydroxythalidomide and glutathione (GSH) conjugate(s) of 5-hydroxythalidomide was investigated in chimeric mice modified with "humanized" liver: novel humanized TK-NOG mice were prepared by the introduction of thymidine kinase, followed by induction with ganciclovir, and human liver cells were transplanted. Following oral administration of racemic thalidomide (100 mg/kg), plasma concentrations of 5-hydroxy- and dihydroxythalidomide were higher in humanized mice than in controls. After administration of 5-hydroxythalidomide (10 mg/kg), higher concentrations of dihydroxythalidomide were detected. These results indicate that livers of humanized mice mediate thalidomide oxidation, leading to catechol and/or the GSH conjugate in vivo and suggest that thalidomide activation occurs.  相似文献   
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