全文获取类型
收费全文 | 41778篇 |
免费 | 1940篇 |
国内免费 | 168篇 |
专业分类
耳鼻咽喉 | 554篇 |
儿科学 | 819篇 |
妇产科学 | 503篇 |
基础医学 | 5373篇 |
口腔科学 | 1294篇 |
临床医学 | 2763篇 |
内科学 | 9795篇 |
皮肤病学 | 890篇 |
神经病学 | 3747篇 |
特种医学 | 2037篇 |
外国民族医学 | 1篇 |
外科学 | 6474篇 |
综合类 | 149篇 |
一般理论 | 6篇 |
预防医学 | 1259篇 |
眼科学 | 822篇 |
药学 | 2691篇 |
中国医学 | 89篇 |
肿瘤学 | 4620篇 |
出版年
2023年 | 205篇 |
2022年 | 373篇 |
2021年 | 677篇 |
2020年 | 413篇 |
2019年 | 538篇 |
2018年 | 654篇 |
2017年 | 563篇 |
2016年 | 711篇 |
2015年 | 671篇 |
2014年 | 923篇 |
2013年 | 1177篇 |
2012年 | 1924篇 |
2011年 | 2006篇 |
2010年 | 1196篇 |
2009年 | 1017篇 |
2008年 | 1823篇 |
2007年 | 2118篇 |
2006年 | 2036篇 |
2005年 | 1967篇 |
2004年 | 1928篇 |
2003年 | 1800篇 |
2002年 | 1838篇 |
2001年 | 1377篇 |
2000年 | 1474篇 |
1999年 | 1344篇 |
1998年 | 608篇 |
1997年 | 478篇 |
1996年 | 444篇 |
1995年 | 367篇 |
1994年 | 360篇 |
1993年 | 341篇 |
1992年 | 1037篇 |
1991年 | 900篇 |
1990年 | 856篇 |
1989年 | 846篇 |
1988年 | 793篇 |
1987年 | 790篇 |
1986年 | 688篇 |
1985年 | 648篇 |
1984年 | 447篇 |
1983年 | 362篇 |
1982年 | 165篇 |
1979年 | 310篇 |
1978年 | 216篇 |
1977年 | 188篇 |
1974年 | 200篇 |
1973年 | 178篇 |
1972年 | 174篇 |
1971年 | 189篇 |
1969年 | 186篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
21.
M Shibata T Ohkubo H Takahashi T Kudo R Inoki 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1986,88(2):101-107
Opiates and opioid peptides were administered in the order of 10(-9)-10(-6) mol peripherally, and their action on pain sensitivity was investigated by the modified formalin test which has two characteristic pain responses (the first and the second phase) in the mouse hindpaw. Opioid peptides (20-500 pmol) had dose-dependent analgesia against both first and second phases, and their action ranked dynorphin greater than [D-Ala2, Met5]-enkephalinamide greater than [Met5]-enkephalin. EKC and morphine (0.4-2.5 nmol) inhibited pain response of the first phase, but produced hyperalgesia in the second phase dose-dependently. Lidocaine hydrochloride had peripheral analgesic action, but was about 500-10000 times weaker than these substances. So, these peripheral analgesic actions have a different mechanism from that of local anesthetic action. N-methyl levallorphan which is thought to be a peripherally selective narcotic antagonist reversed these peripheral analgesic actions at the first and second phases and also prevented the hyperalgesic effects of EKC and morphine at the second phase. Naloxone reversed analgesia at only the first phase. These results suggest that an analgesic mechanism by opioids may exist at the peripheral site as well. Furthermore, it is estimated that a receptor exists which is antagonized by N-methyl levallorphan but not by naloxone and that there is a system of hyperalgesia by EKC and morphine in pain modulation. 相似文献
22.
23.
24.
25.
M Nakayama Y Takahashi H Itoh K Kamiya M Shiratsuchi G Otani 《The Journal of antibiotics》1989,42(11):1535-1540
Two antifungal antibiotics maniwamycins A and B were isolated from the culture broth of a strain of actinomycetes, which were classified as Streptomyces prasinopilosus. These antibiotics were isolated by resin absorption and extraction with EtOAc and purified by column chromatography. Both antibiotics were found to be new azoxy substances from their physico-chemical properties. They showed broad antifungal spectra. 相似文献
26.
27.
Hirofumi Tomiyama Jiko Yamada Yutaka Koji Minoru Yambe Kohki Motobe Kazuki Shiina Yoshio Yamamoto Akira Yamashina 《Hypertension research》2007,30(5):417-426
This observational study of Japanese men without metabolic syndrome (MetS) (age: 41+/-8 years) was conducted to clarify whether or not heart rate elevation precedes the development of full-blown MetS. MetS was defined based on two modifications of the criteria of the Japanese Expert Committee on the Diagnosis and Classification of Metabolic Syndrome. Premetabolic syndrome subjects were defined as those having one component of MetS with increased body mass index (BMI). Among the subjects without MetS (n=1,859 when the BMI criterion was >or=25 and n=2,020 when the BMI criterion was >or=27.5), the incidence of progression to full-blown MetS by the time of the second examination at the end of the 3-year study period was higher in the subjects with premetabolic syndrome than in those without it. The receiver-operator characteristic curve analysis and binary logistic regression analysis revealed that the odds ratio (OR) of a heart rate >or=69 beats/min at the first examination for progression to full-blown MetS by the time of the second examination was significant in subjects with premetabolic syndrome (BMI>or=25: OR=3.64 [1.22-10.88]; BMI>or=27.5: OR=3.67 [1.28-10.55]; p<0.05). Thus, heart rate elevation appears to precede the development of full-blown MetS in subjects with premetabolic syndrome. Heart rate seems to be a simple and useful marker for predicting the progression to full-blown MetS of middle-aged Japanese men with premetabolic syndrome. 相似文献
28.
Ryotaro Wake Masaaki Takeuchi Junichi Yoshikawa Minoru Yoshiyama 《Circulation journal》2007,71(7):1060-1066
BACKGROUND: Gender differences in the predictors of outcome among patients with known or suspected coronary artery disease (CAD) undergoing contrast-enhanced dobutamine stress echocardiography (CE-DSE) have not been completely determined. METHODS AND RESULTS: Follow-up (30+/-17 months) data for 581 men and 309 women with known or suspected CAD who underwent CE-DSE (mean age: 66 years) were obtained. Hard cardiac events included cardiac death and nonfatal myocardial infarction. Total cardiac events included hard cardiac events, unstable angina, congestive heart failure, and late revascularization (>3 months). Cardiac events occurred in 123 male and 50 female patients. Positive results for CE-DSE were associated with worse prognosis in both men and women (2-year total event free rate: 73.5% vs 88.2% in men, p<0.0001, 80.3% vs 91.3% in women, p<0.01). Addition of CE-DSE results, including abnormal left ventricular end-systolic volume response and left ventricular ejection fraction at peak stress <50%, to the clinical and rest echocardiography model provided incremental information for predicting total cardiac events (increase in chi-square value for the model from 60 to 72, p<0.001) in men and (increase in chi-square value for the model from 17 to 32, p<0.001) in women. CONCLUSIONS: CE-DSE provides incremental information for predicting future cardiac events in both men and women. 相似文献
29.
Sho Takahashi Hisato Homma Takehide Akiyama Shinichi Mesawa Kenichiro Hirata Katsuhisa Kogawa Kunihiro Takanashi Hirotoshi Ishiwatari Yutaka Kawano Tsuyoshi Hayashi Kohichi Takada Koji Miyanishi Junji Kato Yoshiro Niitsu 《Nihon Shokakibyo Gakkai zasshi》2007,104(8):1236-1244
A 75-year-old man had been admitted to another hospital because of left abdominal pain, and was given a diagnosis of left hydronephrosis and acute pancreatitis. After a JJ stent insertion and medication, he was transferred to our hospital for further examinations. US and EUS revealed a chronic pancreatitis-like pattern and multicystic lesion in the pancreas head and body. At that time enhanced CT findings showed an extrapancreatic low density area to be inflammatory change, extending from the pancreas body to the left crus of the diaphragm and posteriorly the spreading from the left crus of the diaphragm via the left urinary duct into the left iliopsoas muscle, in which MRI revealed partial high intensity. ERCP and MRCP showed focal irregular narrowing of the pancreatic duct of unknown cause, and we decided that an internal pancreatic fistula due to pancreatitis had induced left ureteral obstruction, caused by a protein plug or alcohol. Follow-up 6 months later showed that extrapancreatic spreading of the low density area had markedly regressed without any change in the ureteral obstruction. 相似文献
30.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414