全文获取类型
收费全文 | 2084篇 |
免费 | 63篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 27篇 |
妇产科学 | 38篇 |
基础医学 | 220篇 |
口腔科学 | 36篇 |
临床医学 | 112篇 |
内科学 | 641篇 |
皮肤病学 | 7篇 |
神经病学 | 218篇 |
特种医学 | 72篇 |
外科学 | 309篇 |
综合类 | 7篇 |
预防医学 | 47篇 |
眼科学 | 16篇 |
药学 | 147篇 |
中国医学 | 5篇 |
肿瘤学 | 245篇 |
出版年
2021年 | 19篇 |
2018年 | 16篇 |
2017年 | 18篇 |
2016年 | 25篇 |
2015年 | 21篇 |
2014年 | 29篇 |
2013年 | 42篇 |
2012年 | 67篇 |
2011年 | 66篇 |
2010年 | 45篇 |
2009年 | 49篇 |
2008年 | 91篇 |
2007年 | 75篇 |
2006年 | 98篇 |
2005年 | 90篇 |
2004年 | 86篇 |
2003年 | 84篇 |
2002年 | 98篇 |
2001年 | 89篇 |
2000年 | 86篇 |
1999年 | 73篇 |
1998年 | 26篇 |
1997年 | 30篇 |
1996年 | 27篇 |
1995年 | 19篇 |
1994年 | 21篇 |
1993年 | 22篇 |
1992年 | 54篇 |
1991年 | 55篇 |
1990年 | 50篇 |
1989年 | 44篇 |
1988年 | 56篇 |
1987年 | 48篇 |
1986年 | 51篇 |
1985年 | 38篇 |
1984年 | 35篇 |
1983年 | 37篇 |
1982年 | 13篇 |
1981年 | 15篇 |
1979年 | 31篇 |
1978年 | 16篇 |
1977年 | 18篇 |
1976年 | 14篇 |
1975年 | 11篇 |
1974年 | 11篇 |
1972年 | 15篇 |
1969年 | 13篇 |
1968年 | 14篇 |
1967年 | 11篇 |
1966年 | 11篇 |
排序方式: 共有2154条查询结果,搜索用时 31 毫秒
61.
Kato M Mizuki A Hayashi T Kunihiro T Nagata H Tsukada N Orikasa H Morinaga S 《Internal medicine (Tokyo, Japan)》2000,39(7):559-563
A 51-year-old man was admitted to our hospital because of hematochezia and painful keratotic plaques involving both hands. He had gastrointestinal polyposis, and a history of liver hemangiomas and thyroid tumor. Numerous papules on the face and papillomatosis on the oral mucosa were present. A diagnosis was made as a typical case of Cowden's disease according to the criteria proposed by Salem and Steck (J Am Acad Dermatol 8: 686, 1983). The patient was not correctly diagnosed initially in spite of typical manifestations of Cowden's disease, mainly due to his concomitant manifestations which occurred chronologically. 相似文献
62.
The CGTCA sequence motif is essential for biological activity of the vasoactive intestinal peptide gene cAMP-regulated enhancer. 总被引:22,自引:1,他引:22
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
63.
Yoshikazu Yonel Iwao Kurose Dai Fukumura Hidetsugu Saito Soichiro Miura Nobuhiro Tsukada Masaya Oda Masaharu Tsuchiya 《Liver international》1994,14(1):37-44
Abstract: A co-culture study of purified rat Kupffer cells and human colon cancer cells was performed, and the process of the tumor cell injury was observed under an inverted type fluorescence microscope loaded with propidium iodide, and also under an electron microscope. Ultrastructurally there was direct membrane-to-membrane interaction between Kupffer cells and colon cancer cells in time. The interaction occurred 1 h after start of the co-culture, and injured tumor cells were observed closely attached to pseudopodia of Kupffer cells at 6 h. The number of propidium iodide-positive tumor cells with damage increased in time. Pretreatment with NG-monomethyl-L-arginine reduced the number of injured tumor cells without preventing morphological interactions, but superoxide dismutase did not prevent the tumoricidal effect. Pretreatment with trypsin completely inhibited cell interaction and damage to tumor cells. In conclusion, the morphological interaction of Kupffer cells as a first step and the involvement of nitric oxide-derived free radicals as a second step seem to play a significant role in the host-defense mechanism. 相似文献
64.
Hidenori Kamiyama Nobuyuki Toyama Yasuaki Mori Kunihisa Miyazaki Makoto Nagano Shigeki Yamada Yoshihisa Suminaga Fumio Konishi 《Journal of hepato-biliary-pancreatic sciences》2002,9(6):759-763
We report a successfully managed case of far‐advanced hepatocellular carcinoma (HCC) by intraarterial infusion therapy. A 55‐year‐old man was admitted to our hospital with abdominal pain and subileus. Abdominal ultrasonography, computed tomography, and angiography revealed HCC with obstruction of the main portal vein due to tumor thrombus. Serum levels of α‐fetoprotein (AFP) and protein induced by vitamin K absence or antagonist‐II (PIVKA‐II) were elevated. Neoadjuvant chemotherapy was tried with a course of low‐dose cisplatin (CDDP) +5‐fluorouracil (5‐FU) intrahepatic arterial infusion through the indwelling catheter via the subcutaneous reservoir port. After 7 weeks of administration (total dose CDDP 370 mg/5‐FU 18.5 mg), the main tumor size was effectively reduced. Serum levels of AFP and PIVKA‐II decreased markedly. Adverse effects were tolerated. Following the chemoinfusion therapy, posterior segmentectomy and thrombectomy were performed. Reconstruction of the portal vein was not necessary because we removed the tumor thrombus without resecting the portal vein. The postoperative course was uneventful, and the patient has been doing well more than 2 years after surgery, with no evidence of recurrence or metastasis. Preoperative low–dose CDDP +5‐FU intrahepatic arterial infusion therapy in combination with hepatic resection may be an effective treatment for advanced HCC with portal vein tumor thrombus. 相似文献
65.
BACKGROUND/AIMS: Nitric oxide is synthesized in diverse mammalian tissues by a family of calmodulin-dependent nitric oxide synthases (NOS). Caveolin, the principal structural protein in caveolae, interacts with endothelial NOS leading to enzyme inhibition in a reversible process modulated by Ca++-calmodulin. The aim of the present study was to clarify the ultrastructural localization of eNOS and caveolin-1 in hepatic sinusoidal endothelium by an electron immunogold method. METHODS: Male Wistar rats were used. Liver tissues and hepatic sinusoidal endothelial cells isolated from rat livers by collagenase infusion were studied. For immunohistochemistry, liver specimens were reacted with anti-eNOS or anti-caveolin-1 antibody. The ultrastructural localization of eNOS or caveolin-1 was identified by electron microscopy using an immunogold post-embedding method. RESULTS: Immunohistochemical studies using liver tissues localized endothelial NOS in hepatic sinusoidal lining cells, portal veins and hepatic arteries; and caveolin-1 in sinusoidal lining cells, bile canaliculi, portal vein and hepatic arteries. Immunogold particles indicating the presence of eNOS and caveolin-1 were demonstrated on the plasma membrane of sinusoidal endothelial fenestrae in liver tissue and also in isolated sinusoidal endothelial cells. CONCLUSION: Endothelial NOS and caveolin are co-localized on sinusoidal endothelial fenestrae, suggesting that interaction of the two may modulate cellular regulation of NO synthesis. 相似文献
66.
BACKGROUND: Coronary vasospasm has been diagnosed by invasive provocative procedures during coronary arteriography. It would be useful to have a reliable, noninvasive, and safe diagnostic method for coronary vasospasm. Regional left ventricular (LV) diastolic dysfunction may persist without systolic dysfunction after an episode of coronary vasospasm. Color kinesis (CK) has been recently developed to facilitate the echocardiographic evaluation of regional wall motion. HYPOTHESIS: Color kinesis may be useful for diagnosis of coronary vasospasm by detection of postischemic regional LV diastolic wall motion abnormality. METHODS: Fifty-one consecutive patients with the last chest symptom within 2 weeks (4 +/- 3 days) were studied echocardiographically. Regional fractional area change during the first 30% of LV filling time in percentage of the segmental end-diastolic area change (CK diastolic index) was used to identify diastolic endocardial motion asynchrony. RESULTS: After diagnostic coronary arteriography with spasm provocation, 26 patients were diagnosed with coronary spastic angina (CSA) and the other 25 with chest pain syndrome (CPS). Regional delayed relaxation (CK-diastolic index < or = 50%) or diastolic asynchrony had been observed in at least one region in 25 (96%) patients with CSA, whereas it had been noted in 2 (8%) patients with CPS. In 17 (65%) patients with CSA, it had been detected in multiple vascular territories, suggesting multivessel spasm. The diastolic asynchrony disappeared in CSA after a month of angina-free period. CONCLUSION: Analysis of CK images allows identification of regional LV delayed relaxation or diastolic asynchrony in patients with coronary vasospasm, differentiating them from patients with chest pain syndrome (sensitivity 96%, specificity 92%). 相似文献
67.
Immunoglobulin class switch from IgG to IgA in a patient with smoldering multiple myeloma 总被引:1,自引:0,他引:1
M Takahashi T Tsukada M Kojima T Koide T Koike H Takahashi C Sakai M Kashimura A Shibata 《Blood》1986,67(6):1710-1713
Serum of a 67-year-old male patient with smoldering multiple myeloma was shown to contain two monoclonal immunoglobulins, IgG and IgA. For the initial seven months, monoclonal IgG was predominantly elevated. During the next one year and eight months, however, serum concentration of the monoclonal IgA increased, with a concomitant decrease of IgG. N-terminal amino acid sequences of heavy and light chains separated from monoclonal IgG and IgA were analyzed. Both light chains were lambda-type and showed identical amino acid sequences of variable regions. The heavy chains also had the same N-terminal amino acid sequence between IgG and IgA. These results strongly suggest that two monoclonal proteins, IgG and IgA, in this patient were produced by B lymphocytes within a clone and that class switch from IgG to IgA in immunoglobulin production during B cell differentiation has taken place in the clinical course of this case. 相似文献
68.
Chiaki Nemoto Yukihiro Ikegami Tsuyoshi Suzuki Yasuhiko Tsukada Yoshinobu Abe Jiro Shimada Choichiro Tase 《General thoracic and cardiovascular surgery》2014,62(11):696-699
To deal with an arterial bleeding from the chest wall after a blunt chest injury, embolization of the bleeding arteries can be a valuable therapeutic option, which is less invasive than a thoracotomy. However, its results are variable, being highly operator-dependent. In the present case, we performed successful emergency embolization of the 4th and 5th intercostal arteries for persistent hemorrhage following blunt trauma to the chest. Several days after the first embolization, secondary embolization was required for treating a pseudoaneurysm that was formed in the 5th intercostal artery. Although the mechanisms underlying pseudoaneurysm formation are not clearly understood, its rupture is potentially fatal. Therefore, it is essential to carefully follow-up patients who experience blunt chest injury to avoid this serious complication. 相似文献
69.
Tsuyoshi Suzuki Chiaki Nemoto Yukihiro Ikegami Tetsuro Yokokawa Yasuhiko Tsukada Yoshinobu Abe Jiro Shimada Yasuchika Takeishi Choichiro Tase 《Journal of anesthesia》2014,28(1):121-124
Takotsubo cardiomyopathy is an acute syndrome involving apical ballooning and consequent dysfunction of the left ventricle. Most cases of left ventricular dysfunction resolve within 1 month. We present the case of a 40-year-old woman who developed severe heart failure caused by takotsubo cardiomyopathy with severe left ventricular dysfunction during the perinatal period. Because of the presence of multiple myomas, she was scheduled to undergo a cesarean section under general anesthesia. However, after induction of general anesthesia, she had to be awakened because of the presence of a difficult airway. Because she exhibited insufficient oxygenation, she was transferred to the emergency center. Upon hospital admission, she expectorated large amounts of pink sputum, indicating severe pulmonary edema. Cesarean section was performed immediately. Echocardiography revealed severe left ventricular dysfunction. Full recovery of cardiac function required almost 1 month, after which she was discharged from the hospital without further complications. This is the first reported case of takotsubo cardiomyopathy induced by a failed intubation during a scheduled cesarean section. Takotsubo cardiomyopathy usually shows a good prognosis, but if this myopathy develops during the perinatal period, it can worsen because of excessive preload following the termination of fetoplacental circulation. 相似文献