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21.
Although electrocardiographic (ECG)-gated magnetic resonance (MR) imaging is widely used for cardiac imaging, it has several disadvantages, such as long imaging time, respiratory artifacts, and motion artifacts induced by arrhythmia. An MR image can be acquired within about 0.3 seconds by using a fast gradient-echo imaging method. When this method is continuously applied, only two to three images can be obtained during a single cardiac cycle. The goal of this study is to obtain cine MR images in a single cardiac cycle using fast gradient-echo imaging combined with the "keyhole" method. The optimal conditions for the keyhole method for cardiac cine imaging were obtained by computer simulation based on a simplified cardiac model. When the read-out direction was set parallel to the cardiac short axis, left ventricular motion was almost correctly reproduced by the keyhole method with acquisition time reduced to one-fourth. J. Magn. Reson. Imaging 1999;10:778-783.  相似文献   
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OBJECTIVE: The purpose of this study was to clarify the significance of bivariate cytokeratin and DNA flow cytometry for analysis of the biologic aggressiveness of resectable non-small cell lung cancer. METHODS: In 92 patients who underwent curative operations, the DNA ploidy status and S-phase fractions of the cancer cell populations inside the tumors were analyzed by a cytokeratin gating technique with paraffin-embedded specimens and were correlated with the surgical results. RESULTS: Ninety tumors yielded assessable DNA histograms. DNA diploidy was detected in 25 tumors with a mean S-phase fraction of 14.3% +/- 4.7%, and DNA aneuploidy was detected in 65 tumors with a mean S-phase fraction of 15.1% +/- 7.1%. The 5-year overall and recurrence-free survivals were 73.3% and 70.3%, respectively. Multivariate analysis showed that only TNM staging was a prognostic factor after surgery. There was a negative correlation between the logarithms of S-phase fraction and the disease-free interval for 22 patients with proven recurrence (P =.006). The tumors with high S-phase fractions recurred more rapidly than did those with low S-phase fractions. CONCLUSION: In a bivariate analysis of cytokeratin and DNA flow cytometry in resectable non-small cell lung cancer, the S-phase fraction appeared to be correlated with the disease-free interval. However, DNA ploidy and S-phase fraction were not predictive of either recurrence or survival after operation. Thus DNA flow cytometry may be of limited use for the analysis of the biologic aggressiveness of lung cancer.  相似文献   
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PURPOSE: We recently reported a protective role of clusterin expression against apoptosis induced by a wide variety of stimuli in several human cancer models. In the current study we tested the hypothesis that clusterin over expression confers a benefit for the metastasis of renal cell carcinoma through the inhibition of apoptosis induced by the various obstacles the cancer cells may confront after detachment from their primary origin. MATERIALS AND METHODS: We introduced clusterin complementary DNA into human renal cell carcinoma ACHN cells, which do not express detectable level of clusterin expression, and generated the clusterin over expressing cell line ACHN/CL and the control vector only transfected cell line ACHN/C. In vitro anti-cell death activity under anchorage independent conditions among ACHN sublines was examined by limiting dilution assay and cell survival assay in suspension. To investigate the in vivo effects of clusterin over expression on metastatic potentials each cell line was injected into the tail vein or renal subcapsule of nonobese diabetic, severe combined immunodeficient mice and the metastatic features in all abdominal and thoracic organs were evaluated. RESULTS: ACHN/CL showed significantly enhanced growth in limiting dilution cultures compared with ACHN/C. The analysis of cell survival in the floating assay also revealed that ACHN/CL had a powerful survival advantage in suspension compared with ACHN/C. Furthermore, ACHN/CL formed more than 5-fold as many metastatic nodules in the lung after intravenous injection than ACHN/C. Similarly more marked lung metastasis was observed after implanting ACHN/CL cells into the renal subcapsule than after implanting ACHN/C cells. In contrast, there were no significant differences among ACHN sublines in the growth rates in vitro and in vivo, cell motility or invasive ability. CONCLUSIONS: These findings suggest that, if clusterin is over expressed, it prolongs cell survival under unfavorable conditions in the metastatic process, resulting in the enhanced metastatic potential of renal cell carcinoma.  相似文献   
26.
Mimatsu K  Oida T  Kawasaki A  Kano H  Fukino N  Kida K  Kuboi Y  Amano S 《Surgery today》2011,41(10):1410-1413
MUC1 expression in cholangiocarcinoma is considered to be correlated with patient survival. We report a case of mass-forming type intrahepatic cholangiocarcinoma (ICC) with direct infiltration of the transverse colon and sequential brain metastasis. The patient was treated by curative right hepatectomy with right hemicolectomy followed by resection of the brain metastasis; there has been no evidence of recurrence in the 7 years since the hepatic resection. Thus, surgical resection may improve the prognosis of ICC involving the adjacent organs, even with brain metastasis. Immunohistochemical staining was performed for MUC1, MUC2, and MUC5AC. Although MUC1 expression was found in the liver tumor and metastatic brain tumor, the correlation between MUC1 expression and the prognosis of this patient was unclear. To clarify the correlation between immunohistochemical characteristics and prognosis, further studies on a greater number of cases of long-term survival of mass-forming type ICC are needed.  相似文献   
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This study was conducted to evaluate the outcome of 88 patients who underwent surgical resection for peripheral non-small cell lung cancers less than 20 mm in diameter. Twenty-one cases with lesions smaller than 10 mm had no lymph node metastasis, intrapulmonary metastasis, pleural dissemination, or distant metastasis. The 5-year survival rate of them was 100%. However, 67 patients with tumors larger than 10 mm showed lymph node metastasis in 14 cases, intrapulmonary metastasis in 3, pleural dissemination in 2 and distant metastasis in 1. And the 5-year survival rates of patients with tumor dimensions of < or = 15 mm and < or = 20 mm were 77.9% and 74.4%, respectively. In addition, patients having adenocarcinoma categorized A and B by Noguchi's classification had no lymph node metastasis, intrapulmonary metastasis, pleural dissemination, or distant metastasis, and showed 100% of 5-year survival rate. To be defined as early cancers in terms of curability, it is thought that the 5-year survival rate of the patients with them is over 95%. Therefore, these results suggest that tumors smaller than 10 mm or adenocarcinoma less than 20 mm in diameter diagnosed as Noguchi's A and B are considered as peripheral early lung cancers.  相似文献   
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Summary We have recently shown that the mechanical efficiency of the contractile machinery of the canine left ventricle is constant at 30%–50%, independent of its loading, heart rate, and inotropic conditions. In contrast, the conventional mechanical efficiency of the ventricle is known to vary between 0 and 30%, depending on these conditions. In this study, we derived an equation for the conventional mechanical efficiency as a function of ventricular preload, afterload, and contractility, based on the constant mechanical efficiency of the contractile machinery. In deriving this equation, we fully utilized our new concept of the total mechanical energy of the left ventricle, i.e., systolic pressure-volume area, and our recent findings of the linear relationship between left ventricular oxygen consumption and the systolic pressure-volume area as well as the dependence of this relation on the ventricular inotropic state. As a result, the conventional mechanical efficiency of the left ventricle was found to change between 0 and 25% as an explicit function of these cardiodynamic and inotropic conditions. Using this function, we obtained combinations of loading and inotropic conditions to maximize the conventional mechanical efficiency of the left ventricle.  相似文献   
29.
OBJECTIVE: The objective of this study was to determine whether the quality of life (QOL) in patients who underwent orthotopic bladder replacement after radical cystectomy was affected by the intestinal segment used for the creation of a neobladder. MATERIALS AND METHODS: A total of 52 patients who underwent radical cystectomy for bladder cancer were included in this study; i.e., 24 patients with an ileal neobladder and 28 patients with a sigmoid neobladder. QOL was evaluated using the SF-36 health-related QOL survey and a questionnaire designed to evaluate the continent status. RESULTS: The mean follow-up periods for patients with an ileal and a sigmoid neobladder was 40.2 and 43.1 months, respectively. The SF-36 survey revealed that patients with colon neobladder had a significantly higher score for role-emotional functioning than those with ileal neobladder, while there was no significant difference in the remaining seven scores between patients with ileal and colon neobladders; however, general health and social functioning in patients with both types of neobladder appeared to be significantly lower than those in the general population in the United States. The results of the questionnaire analyzing the continent status were also similar between these two groups, including the desire to urinate, the incidence of both day- and nighttime urinary leakage, the frequency of pad exchange, and the concern of urine odor. CONCLUSIONS: Six of the eight scales concerning health-related QOL were favorable with both patients with ileal and colon neobladders, and the health-related QOL in orthotopic neobladder patients except for role-emotional functioning was not affected by the segment of the intestine used for neobladder construction. Moreover, no significant differences were observed in the QOL associated with continent status between these two groups. Therefore, patients with both types of orthotopic neobladder were generally satisfied with their health-related as well as disease-specific QOL.  相似文献   
30.
Background  Simultaneous bilateral total hip arthroplasty (THA) can offer a potential benefit of greater postoperative hip motion without the negative influence of contralateral hip disabilities, compared to two-stage THA. However, postoperative changes in hip motion after simultaneous bilateral THA have rarely been reported. The purpose of this study was to clarify the efficacy of simultaneous procedures on postoperative hip motion and functional recovery. Methods  We retrospectively compared hip motion in 27 patients treated with simultaneous bilateral THA to those in 11 patients with two-stage bilateral THA, 35 patients with unilateral THA for unilateral disease, and 15 patients with unilateral THA for bilateral disease. We also evaluated the clinical manifestations according to the Japanese Orthopaedic Association (JOA) hip scores and compared the outcomes among the groups. All of the THA surgeries were primarily performed through a posterolateral approach using cement-less prostheses. The diagnosis at surgery was dysplastic osteoarthritis in all patients, and the patients were followed up for at least 4 years. Results  The postoperative improvement of motion in hip flexion was significantly greater in patients treated with simultaneous procedures compared to patients with two-stage THA and unilateral THA for bilateral disease. The differences in improvement of motion in hip abduction were less marked than the improvement in hip flexion among the groups. Although there were no significant differences in pain scores among the groups, the values for activity of daily living were significantly greater in patients treated with simultaneous bilateral THA and patients with unilateral THA for unilateral disease than in patients with unilateral and two-stage bilateral THA for bilateral disease. Conclusions  The simultaneous procedure was considered to be more effective in patients with bilateral hip osteoarthritis and demonstrated a substantial improvement in hip motion and functional recovery after THA.  相似文献   
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