全文获取类型
收费全文 | 5298篇 |
免费 | 186篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 55篇 |
妇产科学 | 150篇 |
基础医学 | 618篇 |
口腔科学 | 105篇 |
临床医学 | 345篇 |
内科学 | 1176篇 |
皮肤病学 | 46篇 |
神经病学 | 431篇 |
特种医学 | 321篇 |
外科学 | 958篇 |
综合类 | 24篇 |
一般理论 | 1篇 |
预防医学 | 190篇 |
眼科学 | 60篇 |
药学 | 423篇 |
中国医学 | 15篇 |
肿瘤学 | 559篇 |
出版年
2023年 | 37篇 |
2022年 | 49篇 |
2021年 | 93篇 |
2020年 | 36篇 |
2019年 | 59篇 |
2018年 | 56篇 |
2017年 | 56篇 |
2016年 | 56篇 |
2015年 | 60篇 |
2014年 | 78篇 |
2013年 | 111篇 |
2012年 | 210篇 |
2011年 | 225篇 |
2010年 | 119篇 |
2009年 | 89篇 |
2008年 | 206篇 |
2007年 | 263篇 |
2006年 | 237篇 |
2005年 | 231篇 |
2004年 | 197篇 |
2003年 | 212篇 |
2002年 | 253篇 |
2001年 | 212篇 |
2000年 | 246篇 |
1999年 | 221篇 |
1998年 | 103篇 |
1997年 | 66篇 |
1996年 | 64篇 |
1995年 | 43篇 |
1994年 | 46篇 |
1993年 | 33篇 |
1992年 | 144篇 |
1991年 | 145篇 |
1990年 | 137篇 |
1989年 | 124篇 |
1988年 | 119篇 |
1987年 | 106篇 |
1986年 | 101篇 |
1985年 | 99篇 |
1984年 | 56篇 |
1983年 | 49篇 |
1981年 | 27篇 |
1979年 | 55篇 |
1975年 | 30篇 |
1974年 | 26篇 |
1973年 | 27篇 |
1972年 | 34篇 |
1971年 | 26篇 |
1969年 | 34篇 |
1968年 | 28篇 |
排序方式: 共有5496条查询结果,搜索用时 0 毫秒
81.
Ishida H Koyama I Sawada T Murakami T Utsumi K Sannomiya A Tsuji K Tojimbara T Nakajima I Tanabe K Fuchinoue S Yamaguchi Y Toma H Agishi T 《Transplantation》2000,69(1):59-63
BACKGROUND: In organ transplantation, the grafts must be carefully monitored, but it is often difficult to make a quick and accurate diagnosis of unusual changes. Extensive research has failed to identify a useful marker for rejection. We investigated the clinical utility of sialyl Lewis(X) (CD15s) monitoring in 17 renal transplant patients with acute rejection. METHODS: The expression of CD15s on peripheral lymphocytes was examined using flow cytometry in renal transplant recipients with rejection (n=17), without rejection (n=23), recipients infected with cytomegalovirus (n=7), recipients with other diseases (n=7), and healthy volunteers (n=18). CD15s expression was compared with histological findings, and was also examined before and after steroid pulse therapy to investigate the effects of steroids on CD15s antigen expression on the surface of the peripheral lymphocytes. RESULTS: CD15s was strongly expressed in all patients with rejection, but was not expressed in any of the patients without rejection or in any healthy volunteers. Histologically, cell infiltration into the rejected graft was moderate or severe in all patients with strong expression of CD15s. In contrast, no or only mild infiltration was observed in patients with weak expression of CD15s. In addition, 14 of 17 patients (14/17, 82%) with strong CD15s expression improved upon administration of steroid pulse therapy, although there was no benefit from steroids in any of the patients with weak expression of CD15s. CONCLUSIONS: The CD15s antigen is expressed strongly on the peripheral lymphocytes at the time of rejection. It is interesting that the efficacy of steroid therapy in the patients with elevated creatinine could be predicted by CD15s expression on the peripheral lymphocytes before graft biopsy. There have been only few reports showing the relationship between CD markers and the efficacy of the treatment in patients with elevated creatinine. We report that the detection of CD15s on the peripheral lymphocytes by flow cytometry was an easy, helpful, and noninvasive means for the diagnosis and treatment of patients with elevated creatinine after renal transplantation. 相似文献
82.
Takeshi Tominaga Hiroki Koyama Tetsuya Toge Shigeto Miura Keizo Sugimachi Susumu Yamaguchi Koichi Hirata Yasumasa Monden Yasuo Nomura Masakazu Toi Izo Kimijima Shinzaburo Noguchi Hiroshi Sonoo Kazuaki Asaishi Tadashi Ikeda Tadaoki Morimoto Jun Ota Yasuo Ohashi Osahiko Abe 《Journal of clinical oncology》2003,21(6):991-998
PURPOSE: We compared the therapeutic usefulness of doxifluridine (5'-DFUR) alone and a combination of 5'-DFUR plus cyclophosphamide (CPM), both of which are considered effective against advanced and recurrent breast cancer, to determine which treatment is more beneficial as postoperative adjuvant chemotherapy. PATIENTS AND METHODS: A total of 1,131 women with node-positive primary breast cancer were randomly assigned after primary surgery to receive 5'-DFUR alone or 5'-DFUR plus CPM. All patients initially received 5'-DFUR in an oral dose of 1,200 mg/d for 4 weeks, starting 4 weeks after surgery. Chemotherapy was then not given for 2 weeks. Patients in the 5'-DFUR group subsequently received five 4-week cycles of treatment consisting of oral 5'-DFUR (1,200 mg/d) for the first 2 weeks and no chemotherapy for the next 2 weeks. Those assigned to the 5'-DFUR plus CPM group also received oral CPM 100 mg/d for the first 2 weeks and no chemotherapy for the next 2 weeks. Women 50 years or older concurrently received 20 mg/d of tamoxifen for 2 years in both groups. RESULTS: Of the 1,088 eligible women, 546 were assigned to receive 5'-DFUR alone and 542 were assigned to receive 5'-DFUR plus CPM. Overall disease-free survival was significantly better in women who received 5'-DFUR plus CPM than in those who received 5'-DFUR alone (log-rank test, P =.021). Toxic effects occurred in 20.0% of patients (109 of 546) in the 5'-DFUR group and 32.3% of patients (175 of 542) in the 5'-DFUR plus CPM group (chi(2) test, P <.001). CONCLUSION: Combination therapy with 5'-DFUR plus CPM is more effective in preventing recurrence than 5'-DFUR alone. 相似文献
83.
84.
Hitoshi Kotanagi Toshiaki Yoshioka Osamu Muto Hiroshi Kon Ryuichi Yanagida Masanao Ito Toshiki Kikuchi Kenji Koyama 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(3):133-137
Background Japanese surgeons have to macroscopically assess nodal metastasis from colon cancer according to the general rules established
in Japan. Adjuvant therapy is sometimes started after macroscopic assessment of nodal metastasis. Macroscopic assessment,
however, is difficult in many cases.
Methods We evaluated the reliability of macroscopic assessment of nodal metastasis in colon cancer by (1) comparing the number of
nodes picked up macroscopically with that of nodes recognized microscopically, and (2) by comparing the number of metastatic
nodes found between macroscopic and microscopic examination.
Results The number of nodes found during macroscopic examination was equal to that found in microscopic examination in only 52 of
206 cases (25%). Although 120 of 206 cases (58%) were judged macroscopically to have metastatic nodes, 61 had no metastatic
nodes found microscopically. Sensitivity and specificity for the recognition of cases with nodal metastasis was 85.5% and
55.5%, respectively. The number of metastatic nodes in macroscopic examination was equal to that in microscopic examination
in 90 cases (44%).
Conclusion Because macroscopic assessment of nodal metastasis is not reliable, physicians should not rely on macroscopic assessment to
indicate the need for further therapy, such as adjuvant chemotherapy. The recommendation for macroscopic assessment of nodal
metastasis should be eliminated from the general rules in Japan. 相似文献
85.
Homotypic Adhesion through Carcinoembryonic Antigen Plays a Role in Hepatic Metastasis Development 总被引:2,自引:0,他引:2
Toshiaki Yoshioka Takashi Masuko Hitoshi Kotanagi Osamu Aizawa Yuri Saito Hiroshi Nakazato Kenji Koyama Yoshiyuki Hashimoto 《Cancer science》1998,89(2):177-185
We established a cell line with high metastatic potential to the liver (LS-LM4) after four successive repetitions of splenic injection of liver-metastatic cells in SCID mice. This cell line strongly expressed CEA and showed increased homotypic adhesion as compared with the parent cell line (LS174T). To examine the role of CEA in the increased homotypic adhesion, LS-LM4 cells were treated with anti-CEA antibody and subjected to an in vitro adhesion and aggregation assay. Further, to study the role of CEA in the hepatic metastasis of cells with high metastatic potential, LS-LM4 cells were treated with anti-CEA antibody, and the inhibition of hepatic metastasis after splenic injection in vivo was examined. There was a 62% decrease in the homotypic adhesion of anti-CEA antibody-treated (100 μg/ml) LS-LM4 cells under a Ca2+ -free condition as compared with the control ( P <0.01). Anti-CEA antibody (100 μg/ml) inhibited cell aggregation under a Ca2+ -free condition ( P <0.05). Treatment with anti-E-cadherin antibody (60 μ/ml) plus anti-CEA antibody (100 μg/ml) inhibited cell aggregation more potently than anti-E-cadherin antibody treatment alone in the presence of Ca2+ . In vivo , there was a 75% decrease in the number of hepatic metastatic nodules in the G125 anti-CEA antibody-treated group as compared with the control group ( P <0.01). Similarly, there was a 40% decrease in the diameter of metastatic nodules and there was a 90% decrease in total tumor volume of hepatic metastasis in the G125 anti-CEA antibody-treated group as compared with the control ( P <0.01). These results suggest that increased metastatic potential to the liver is at least partly due to increased homotypic binding mediated by CEA. 相似文献
86.
The present study examined effect of administration of a selective D1 dopamine receptor agonist, SKF38393 on extracellular concentrations of glutamate (Glu) and gamma-aminobutyric acid (GABA) in mPFC, by using in vivo microdialysis. Perfusion with SKF38393 via a dialysis probe reduced concentrations of both Glu and GABA dose-relatedly, and these effects were prevented by co-perfusion with a D1 dopamine receptor antagonist, SCH23390 (40 microM). These results suggested that the dopaminergic hyperactivity may lead to the hypofunction of glutamatergic and GABAergic systems in mPFC via D1 dopamine receptor stimulation. 相似文献
87.
Shinozuka N Koyama I Arai T Numajiri Y Watanabe T Nagashima N Matsumoto T Ohata M Anzai H Omoto R 《American journal of surgery》2000,179(1):42-45
BACKGROUND: Homologous blood transfusion (HBT) has the risk of an immunosuppressive effect and may adversely affect the prognosis of patients with carcinomas. Autologous blood transfusion (ABT) has not yet become a standard procedure in gastroenteric cancer surgery. We investigated the usefulness and problems of ABT combined with the use of recombinant human erythropoietin (rh-EPO). METHODS: An evaluation of autologous blood transfusion (ABT) combined with recombinant human erythropoietin (rh-EPO) treatment was conducted in 46 patients with hepatocellular carcinoma undergoing hepatectomy. Preoperative autologous blood donation (ABD) was accomplished for 25 of the 46 patients. The preoperative changes in hemoglobin and hematocrit in relation to route of administration of erythropoietin were studied. In addition, intraoperative blood requirements and the postoperative complications for patients who predonated were compared with those of patients who underwent surgery without autologous predonation. RESULTS: The proportion of patients not requiring additional homologous blood transfusions (HBT) during operation was significantly higher in the ABD group than in the non-ABD group (88% versus 38%). The incidence of postoperative complications was significantly higher in patients receiving HBT than in nontransfused patients and in those receiving ABT. CONCLUSIONS: Preoperative autologous blood donation in combination with rh-EPO therapy markedly reduced the requirement for homologous blood transfusion during surgery in patients with hepatocellular carcinoma having hepatectomy. 相似文献
88.
Compensatory renal hypertrophy and changes of renal function following nephrectomy 总被引:11,自引:0,他引:11
Sugaya K Ogawa Y Hatano T Koyama Y Miyazato T Naito A Yonou H Kagawa H 《Hinyokika kiyo. Acta urologica Japonica》2000,46(4):235-240
We studied the changes in the serum creatinine level and the volume of the remaining kidney following nephrectomy using contrast-enhanced compounded tomogram (CT) scans. Twenty-five patients undergoing nephrectomy for renal cell carcinoma without obvious disease in the remaining kidney were carefully followed for a period of at least two years at our hospital. Twelve patients received follow-up CT scans each year after nephrectomy. The ellipsoid volume of the kidney was calculated by measuring the 3-dimensional size on CT scans. The mean relative volume (%) of the remaining kidney increased up to year 3 postoperatively, and the final mean relative volume at varying periods from years 2 to 7 was 120%. Kidneys that were smaller prior to nephrectomy showed a tendency to have a larger final relative volume after nephrectomy, although there was no significant correlation between the kidney volume prior to nephrectomy and at final measurement. The mean serum creatinine level was significantly increased at one year after nephrectomy, but it decreased significantly over time. Therefore, both compensatory renal hypertrophy and improved renal function seemed to be established within several years after nephrectomy. However, the improvement of serum creatinine was delayed compared with the increase of kidney volume. That is, renal plasma flow might be increased early by compensatory renal hypertrophy, followed within a few years by an increase in glomerular filtration and a decrease of serum creatinine. 相似文献
89.
90.
Shiraishi Y Nakajima Y Koyama A Takasuna K Katsuragi N Yoshida S 《The Annals of thoracic surgery》2000,70(4):1202-6; discussion 1206-7
BACKGROUND: Extrapleural pneumonectomy is still indicated in some patients with empyema. We examined morbidity and mortality after this high-risk operation. METHODS: Between 1979 and 1998, 94 (92 chronic, 2 postsurgical) patients with empyema underwent extrapleural pneumonectomy. There were 79 men and 15 women (mean age, 59 years). Eighty-eight patients had a history of tuberculosis, and 53 had undergone a therapeutic pneumothorax. The right side was operated on in 50 patients and left in 44. RESULTS: Operative mortality was 8.5%. Fifteen major complications (1 esophageal perforation, 9 empyemas, and 5 bronchopleural fistulas) occurred in 13 patients. Eight patients required reexploration for hemorrhage. Reexploration was a risk factor for empyema. Bronchopleural fistulas occurred only on the right side. Eighty-nine percent of the 86 operative survivors were free of empyemas at 5 years. Overall 5-year survival was 83%, and survival was better in patients without than in those with empyema. CONCLUSIONS: Extrapleural pneumonectomy for empyema has acceptable morbidity and mortality. Postoperative empyema affects prognosis. Covering a bronchial stump with muscle is recommended, especially when the operation is performed on the right side. 相似文献