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81.
Primary hepatocellular carcinoma (HCC) in patients <30 years old is extremely rare. In younger patients, HCC develops against a background of persistent hepatitis B virus infection. We herein report a 23-year-old woman with HCC with all-negative hepatitis virus markers developing in an apparently healthy liver. Imaging studies showed a 50-mm hypervascular mass in segment 4 of the left liver lobe, compatible with HCC. The patient underwent surgical resection. A histological examination showed the presence of poorly differentiated HCC. The patient was diagnosed with HCC developing in a healthy liver. This is an extremely rare case of non-B non-C HCC.  相似文献   
82.
The aim of this study was to investigate the influence of systemic chemotherapy on the skeletal growth of young osteosarcoma patients as a treatment-related late adverse effect. We reviewed the height data of 20 osteosarcoma patients (13 males and 7 females) aged ≤18 years. The average (±SD) age at diagnosis was 14.5 (±3.3) years. The average follow-up interval was 89.6 months. After wide resection of the affected bones, reconstruction with tumor prostheses and auto-bone grafting was carried out in 11 and 9 cases, respectively. Pearson’s correlation coefficient was calculated to evaluate the association between actual and predicted (using Paley’s multiplier method) heights. Z-scores were used to compare the initial and final heights with the Japanese national growth curve. Actual and predicted heights were correlated according to Pearson’s correlation coefficient (R = 0.503). Z-analysis showed that statistical significance (p = 0.04) was noted for the height data Z-scores of patients between ≤10 years and >10 years at the final follow-up. Systemic chemotherapy did not reduce skeletal growth in young osteosarcoma patients as a late adverse effect based on two different evaluation methods. However, patients aged ≤10 years at diagnosis may develop a short stature after systemic chemotherapy.  相似文献   
83.
Duloxetine is widely used for pain control and depressive syndromes. One of its potential side effects is syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Duloxetine-induced SIADH causes hyponatremia, which leads to a variety of symptoms and has previously been reported in the elderly. In the present case, we experienced a case of the rapid onset of SIADH in a super-elderly woman receiving low-dose duloxetine. Elderly patients tend to have lower duloxetine doses and an earlier onset than non-elderly patients. When hyponatremia occurs after duloxetine administration, duloxetine-induced SIADH should be considered, especially in high-risk elderly patients, regardless of the duloxetine dose or duration of treatment.  相似文献   
84.
Erk pathways negatively regulate matrix mineralization   总被引:1,自引:0,他引:1  
Skeletal mineralization is an important step regulating the mechanical properties of the calcified tissues, but molecular events underlying mineralization still remain elusive. We examined the role of extracellular signal-regulated kinase (Erk) pathways in matrix mineralization of osteogenic cells both in vitro and in vivo. Matrix mineralization by preosteocytic MLO-A5 cells and osteoblastic MC3T3-E1 cells was increased by either PD98059 Mek inhibitor treatment or adenovirus vector-mediated dominant negative Ras (Ras(DN)) expression and was suppressed by Erk activation by platelet-derived growth factor (PDGF) treatment or constitutively active Mek1 (Mek(CA)) expression. Administration of adenovirus vectors carrying Ras(DN) gene onto the calvaria of 1-day-old mice increased the mineralization of the tissues, while that of the Mek(CA) adenovirus suppressed it. These results suggest that the Erk pathway is a negative regulator of the matrix mineralization both in vitro and in vivo.  相似文献   
85.
Prognostic significance of Bcl-xL in human hepatocellular carcinoma   总被引:10,自引:0,他引:10  
BACKGROUND: Proliferation and apoptosis of liver cancer cells are closely related phenomena. We investigated the correlation between overexpression of Bcl-xL, an anti-apoptosis-related protein of the Bcl-2 family, and the clinical course of hepatocellular carcinoma (HCC). METHODS: Specimens from 7 HCC patients were used for Western blotting and immunoelectron microscopy tests. Samples from 33 HCC patients who had undergone hepatectomies were used for immunohistochemical staining. The degrees of expression of Bcl-xL and Ki-67, as an index of HCC mitosis severity, were each classified into 2 groups. RESULTS: With the use of Western blot analysis, enhanced immunoreactivity of Bcl-xL was found in cancerous specimens. Bcl-xL overexpression was found in cancer specimens in 21 of 33 patients (63.6%). The overall survival (P=.019) and disease-free survival (P=.030) rates of the group overexpressing Bcl-xL were definitely poorer. The Ki-67 higher labeling index LI > 10) group had a poorer survival rate (P=.016). There were significant correlations between Bcl-xL and overall survival and disease-free survival. Multivariate analyses revealed that Bcl-xL, tumor size, histologic portal invasion, and histologic metastatic foci were independent prognostic factors for overall survival and disease-free survival. CONCLUSIONS: These results showed Bcl-xL in HCC specimens, suggesting that Bcl-xL was a significant prognostic factor for disease progression in human HCC.  相似文献   
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89.
The dorsolateral pontine nucleus (DLPN) is a major component of the cortico-ponto-cerebellar pathway that carries signals essential for smooth pursuit. This pathway also carries visual signals that could play a role in visually guided motor learning in the vestibular ocular reflex (VOR). However, there have been no previous studies that tested this possibility directly. The aim of this study was to determine the potential role of the DLPN in short-term VOR gain adaptation produced by viewing a scene through lenses placed in front of both eyes. In control experiments, adaptation of VOR gain was achieved by sinusoidal rotation (0.2 Hz, 30 degrees /s) for 2 h while the monkey viewed a stationary visual surround through either magnifying (x2) or minifying (x0.5) lenses. This led to increases (23-32%) or decreases (22-48%) of VOR gain as measured in complete darkness (VORd). We used injections of muscimol, a potent GABA(A) agonist (0.5 microl; 2%), to reversibly inactivate the DLPN, unilaterally, in three monkeys. After DLPN inactivation, initial acceleration of ipsilateral smooth-pursuit was reduced by 35-68%, and steady-state gain was reduced by 32-61%. Despite these significant deficits (P < 0.01) in ipsilesional smooth pursuit, the VOR during lens viewing was similar to that measured in preinjection control experiments. Similarly, after 2 h of adaptation, VORd gain was not significantly different (P > 0.61) from control adaptation values for either ipsi- or contralesional directions of head rotation. This was the case even though a stable ipsilesional smooth pursuit deficit persisted throughout the full adaptation period. Our results suggest that visual error signals for short-term adaptation of the VOR are derived from sources other than the DLPN perhaps including other basilar pontine nuclei and the accessory optic system.  相似文献   
90.
Sawada M  Watanabe S  Tsuda H  Kano T 《Anesthesia and analgesia》2002,94(6):1416-20, table of contents
Radiofrequency ablation (RFA) therapy using an active needle electrode inserted into liver tumors has been used clinically. To avoid hyperthermia, we investigated the relationship between the total output energy of the applied radiofrequency wave and changes in body temperature (BT) in patients receiving RFA. Fifteen patients undergoing RFA of liver tumors with general anesthesia were enrolled. The total output energy of radiofrequency waves was calculated from the power and duration of RFA. Changes in rectal (T(rect)) and tympanic temperatures were measured throughout the study. The mean number of liver tumors per patient was 1.7 +/- 1.3. The mean RFA time was 30.0 +/- 26.3 min. The mean total output energy was 125,935 +/- 114,506 J. The mean value of T(rect) increased from 36.3 degrees C +/- 0.5 degrees C to 37.0 degrees C +/- 1.0 degrees C (P < 0.01). A linear correlation was obtained between the total output energy and the changes in T(rect), indicating that T(rect) increased approximately by 1 degrees C for every 3000 J/kg of total output energy. The increase in BT during RFA of liver tumors under general anesthesia is predictable. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors. IMPLICATIONS: The increase in body temperature (BT) is predictable during radiofrequency ablation (RFA) of liver tumors under general anesthesia. Close observation of total output energy delivered and BT are required, and preparation of cooling measures is important, in RFA of liver tumors.  相似文献   
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