全文获取类型
收费全文 | 7388篇 |
免费 | 327篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 60篇 |
儿科学 | 155篇 |
妇产科学 | 93篇 |
基础医学 | 835篇 |
口腔科学 | 155篇 |
临床医学 | 457篇 |
内科学 | 1732篇 |
皮肤病学 | 128篇 |
神经病学 | 723篇 |
特种医学 | 352篇 |
外科学 | 1098篇 |
综合类 | 23篇 |
一般理论 | 1篇 |
预防医学 | 239篇 |
眼科学 | 135篇 |
药学 | 671篇 |
中国医学 | 7篇 |
肿瘤学 | 902篇 |
出版年
2023年 | 52篇 |
2022年 | 92篇 |
2021年 | 181篇 |
2020年 | 103篇 |
2019年 | 106篇 |
2018年 | 128篇 |
2017年 | 118篇 |
2016年 | 124篇 |
2015年 | 127篇 |
2014年 | 168篇 |
2013年 | 201篇 |
2012年 | 340篇 |
2011年 | 351篇 |
2010年 | 214篇 |
2009年 | 172篇 |
2008年 | 311篇 |
2007年 | 370篇 |
2006年 | 353篇 |
2005年 | 393篇 |
2004年 | 362篇 |
2003年 | 309篇 |
2002年 | 354篇 |
2001年 | 215篇 |
2000年 | 266篇 |
1999年 | 229篇 |
1998年 | 112篇 |
1997年 | 108篇 |
1996年 | 76篇 |
1995年 | 59篇 |
1994年 | 57篇 |
1993年 | 55篇 |
1992年 | 154篇 |
1991年 | 136篇 |
1990年 | 149篇 |
1989年 | 147篇 |
1988年 | 132篇 |
1987年 | 125篇 |
1986年 | 122篇 |
1985年 | 125篇 |
1984年 | 89篇 |
1983年 | 52篇 |
1982年 | 31篇 |
1981年 | 33篇 |
1980年 | 26篇 |
1979年 | 49篇 |
1978年 | 24篇 |
1976年 | 20篇 |
1975年 | 23篇 |
1972年 | 20篇 |
1969年 | 34篇 |
排序方式: 共有7766条查询结果,搜索用时 15 毫秒
41.
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
42.
Abstract: Membrane Autotransfusion System (MATS) utilizing plasmapheresis technology has been developed in our laboratory. A specially designed polyethylene hollow fiber membrane was utilized. This study was conducted to evaluate performance of the first experimental prototype, MATS-I. The results of this study showed that the MATS-I could concentrate diluted blood at 10% of the initial hematocrit concentration (HCTi) into over 40% after passing through the system at a transmembrane pressure of 70 mm Hg. Moreover, the MATS-I can continuously treat 10,000 ml of diluted blood at various HCTi levels without deteriorating its performances. Even though the MATS-I met all required performances as an autotransfusion system, several areas of improvement of the system were necessary to meet various clinical needs. The next prototype, MATS-II, can be designed based on experiences obtained from the MATS-I. The MATS is smaller, more atraumatic and continuous, and is a faster system when compared to the currently available centrifugal autotransfusion devices. 相似文献
43.
The expression of alternatively spliced mRNAs for amyloid precursor protein (APP) isoforms and their translation products were examined in the rat cerebral cortex 1, 3, 6, and 12 h and 1, 3, and 7 days (n = 4-5 in each group) after fluid-percussion brain injury. In situ hybridization studies demonstrated that the expression of APP695 mRNA decreased in and around the damaged area of the cerebral cortex exposed to fluid-percussion injury 1 h after the insult. On the other hand, APP751/770 mRNAs were increased in the regions surrounding the damaged cortical areas 1 day after the injury. An increase of immunoreactive APP was detected in the regions around the damaged cortical areas 3 h after traumatic injury and maintained for the following 3 days. The APP immunoreactivity in the damaged cortices declined to the level of sham-operated animals by post-experimental day 7. Using an anti-amyloid beta (Abeta) protein (17-24) antibody, no deposits of immunoreactive Abeta (17-24) were observed in any of the samples examined in these experiments. These results suggest that the induction of Kunitz-type protease inhibitor (KPI) domain-containing APP mRNAs and the increased accumulation of APP are involved in the physiological and neuropathological responses of brains under various neurodegenerative conditions, including head trauma. 相似文献
44.
Therapeutic Value of Neoadjuvant Intra-arterial Chemotherapy (Cisplatin) and Irradiation for Locally Advanced Uterine Cervical Cancer 总被引:1,自引:0,他引:1
Takafumi Toita Kaoru Sakumoto Masahiro Higashi Kazuhiko Ogawa Yasumasa Kakinohana Sanae Shinzato Hidehiko Moromizato Koji Kanazawa Satoshi Sawada 《Gynecologic oncology》1997,65(3):421-424
We analyzed long-term treatment results in 51 patients with locally advanced uterine cervical carcinoma (IIB, 4; IIIB, 43; IVA, 4) treated with neoadjuvant intra-arterial (I-A) chemotherapy (cisplatin) via the uterine artery and irradiation. Thirty patients (58.8%) developed recurrence. Twelve had pelvic recurrence alone, 8 had distant metastases alone, and 10 had both pelvic and distant failure. The 5-year cumulative pelvic control rate, absolute survival rate, and disease-free survival rate were 55.3, 47.1, and 39.4%, respectively. Eight of 51 patients (15.7%) suffered late complications. These results suggest that our neoadjuvant I-A chemotherapy prior to irradiation has limited additional value for long-term prognosis in patients with locally advanced uterine cervical carcinoma. 相似文献
45.
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
46.
Pure red cell aplasia and myasthenia gravis with thymoma: a case report and review of the literature 总被引:3,自引:0,他引:3
Mizobuchi S; Yamashiro T; Nonami Y; Yamamoto A; Kume M; Nakaya H; Sawada T; Taguchi H; Moriki T; Ogoshi S 《Japanese journal of clinical oncology》1998,28(11):696-701
A case of pure red cell aplasia (PRCA), myasthenia gravis (MG) and thymoma
is reported. A 70-year-old woman presented with severe anemia. She had been
diagnosed as having MG 8 years earlier and her symptoms were adequately
controlled with ambenonium chloride. When she visited our hospital, her
hematocrit was 13.7% with a hemoglobin concentration of 4.7 g/dl and her
reticulocyte counts were persistently abnormal at 0.1%. Although both
direct and indirect Coombs' tests were positive, there was no evidence of
hemolysis. Routine screening tests for other etiologies of anemia were
negative. Serological tests for anti-DNA and anti-acetylcholine receptor
antibodies gave positive results. A bone marrow examination revealed severe
erythroid hypoplasia. PRCA was diagnosed and the patient was treated with
periodic transfusions. A lateral view chest roentgenogram and a computed
tomography scan of the thorax showed the presence of an anterior
mediastinal mass which was suspected to be thymoma. The patient underwent
thymothymectomy and the tumor was diagnosed as a thymoma. Although the
patient received no treatment for MG and PRCA after surgery, her
hematological test results rapidly improved and she was discharged from the
hospital on the 29th postoperative day. At that time, her hematocrit was
33.2%, her hemoglobin concentration was 10.0 g/dl, her peripheral
reticulocyte level was 1.8% and her left partial ptosis had improved. She
is doing well, 9 months after surgery. For a patient to remain in remission
without treatment for PRCA and MG after thymothymectomy is extremely rare.
相似文献
47.
Ryugo Sawada Hisako Hotta Yong-Suk Chung Michio Sowa Tadashi Tai Ikuya Yano 《Cancer science》1998,89(2):167-176
Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 Neu-Acα-LacCer, II3 NeuAcα2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3+ Gb4=58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Lea (pentaglycosylceramide) and Leb (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells. 相似文献
48.
Masumura M Hata R Nishimura I Uetsuki T Sawada T Yoshikawa K 《Brain research. Molecular brain research》2000,80(2):219-227
To elucidate the mechanism of neuronal death in Alzheimer's disease, we investigated the effects of overexpression of wild-type Alzheimer amyloid precursor protein (APP) on neuronal cells and glial cells in vivo. When an APP695-expressing adenovirus was injected into the dorsal hippocampal region, a number of neurons in remote areas were positively stained with anti-APP monoclonal antibody, and underwent severe degeneration from 3 to 7 days after viral inoculation. Most degenerating neurons were immunopositive with both APP and activated caspase-3, but some neurons that expressed activated caspase-3 were not expressing APP from 7 to 14 days after virus injection. In the neighborhood of the degenerating neurons, activated microglia/macrophages, which were identified by the phenotypic marker C3bi receptor (CD11b/c; OX-42), were observed, and some of them appeared to phagocytose the caspase-3-immunopositive degenerating neurons. In addition to microglia/macrophages, infiltrating leukocytes expressing CD45 or CD4 were also detected. These results suggest that the increased accumulation of APP induced not only caspase-3-mediated death machinery, but also inflammatory responses including microglial activation. These inflammatory responses might cause further neurodegeneration through the alternative pathway that might activate the caspase-3-mediated death machinery without APP expression. 相似文献
49.