全文获取类型
收费全文 | 8430篇 |
免费 | 424篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 238篇 |
儿科学 | 84篇 |
妇产科学 | 122篇 |
基础医学 | 942篇 |
口腔科学 | 156篇 |
临床医学 | 514篇 |
内科学 | 2065篇 |
皮肤病学 | 129篇 |
神经病学 | 952篇 |
特种医学 | 263篇 |
外科学 | 1567篇 |
综合类 | 17篇 |
预防医学 | 235篇 |
眼科学 | 120篇 |
药学 | 622篇 |
中国医学 | 14篇 |
肿瘤学 | 853篇 |
出版年
2023年 | 56篇 |
2022年 | 100篇 |
2021年 | 164篇 |
2020年 | 126篇 |
2019年 | 147篇 |
2018年 | 202篇 |
2017年 | 149篇 |
2016年 | 150篇 |
2015年 | 199篇 |
2014年 | 236篇 |
2013年 | 293篇 |
2012年 | 443篇 |
2011年 | 459篇 |
2010年 | 263篇 |
2009年 | 246篇 |
2008年 | 385篇 |
2007年 | 436篇 |
2006年 | 392篇 |
2005年 | 414篇 |
2004年 | 389篇 |
2003年 | 376篇 |
2002年 | 369篇 |
2001年 | 273篇 |
2000年 | 264篇 |
1999年 | 224篇 |
1998年 | 85篇 |
1997年 | 68篇 |
1996年 | 55篇 |
1995年 | 49篇 |
1994年 | 67篇 |
1993年 | 51篇 |
1992年 | 197篇 |
1991年 | 173篇 |
1990年 | 141篇 |
1989年 | 179篇 |
1988年 | 124篇 |
1987年 | 132篇 |
1986年 | 100篇 |
1985年 | 95篇 |
1984年 | 61篇 |
1983年 | 57篇 |
1979年 | 53篇 |
1978年 | 30篇 |
1977年 | 29篇 |
1976年 | 29篇 |
1975年 | 32篇 |
1974年 | 37篇 |
1973年 | 33篇 |
1972年 | 32篇 |
1968年 | 26篇 |
排序方式: 共有8893条查询结果,搜索用时 15 毫秒
81.
82.
Masashi Yokoi Tsuyoshi Ito Takafumi Nakayama Hiroshi Fujita Tomonori Sugiura Yoshihiro Seo 《Medicine》2022,101(20)
The effect of renal dysfunction on clinical outcomes following fractional flow reserve (FFR)-guided deferral of revascularization remains unelucidated.We retrospectively analyzed 224 patients with atherosclerotic coronary lesions who underwent deferred revascularization based on an FFR of >0.80. The median follow-up interval was 28.1 months. Patients were divided into 2 groups: the hemodialysis (HD) and the non-HD group. The non-HD group was further classified into 2 subgroups according to their estimated glomerular filtration rate (eGFR) level: eGFR <45, equivalent to chronic kidney disease stage 3b-5 and eGFR ≥45. We evaluated major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction, and any revascularization.MACE occurred in 36 patients (16.1%). The rate of HD was significantly higher in the MACE group (19% vs 6%, P < .01). In non-HD patients, the eGFR was significantly lower in the MACE group (51.2 vs 63.2 mL/min/1.73 m2, P < .01). Overall, univariate Cox regression analysis revealed a significant relationship between HD and MACE (HR 2.91, P = .01), as did the multivariate model (HR 2.90, P = .01). Of the MACE, more deaths occurred in HD patients (15.8% vs 2.9%, P = .03). Among non-HD patients, eGFR <45 (HR 2.70, P = .02), FFR (per 0.01, HR 0.87, P < .01), and low-density lipoprotein cholesterol (per 10 mg/dL, HR 1.17, P = .02) were independent predictors of MACE. Any revascularization was more common in patients with eGFR<45 than in those with eGFR ≥45 (21.4% vs 7.3%, P = .02). Kaplan–Meier estimates revealed that the HD group showed a significantly lower MACE-free survival rate than the nonHD group (log-rank P < .01). In non-HD patients, the eGFR<45 group showed a lower MACE-free survival rate than the eGFR ≥45 group (log-rank P = .01).HD and reduced eGFR in non-HD patients were associated with adverse cardiac events after FFR-guided deferral of revascularization. 相似文献
83.
Ho N. Nguyen Naoko Miyagawa Katsuyuki Miura Nagako Okuda Katsushi Yoshita Yusuke Arai Hideaki Nakagawa Kiyomi Sakata Toshiyuki Ojima Aya Kadota Naoyuki Takashima Akira Fujiyoshi Takayoshi Ohkubo Robert D. Abbott Tomonori Okamura Akira Okayama Hirotsugu Ueshima 《Clinical nutrition (Edinburgh, Scotland)》2018,37(1):182-188
84.
85.
86.
87.
Purification to homogeneity and characterization of human B-cell differentiation factor (BCDF or BSFp-2). 总被引:39,自引:6,他引:39 下载免费PDF全文
T Hirano T Taga N Nakano K Yasukawa S Kashiwamura K Shimizu K Nakajima K H Pyun T Kishimoto 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(16):5490-5494
Human B-cell differentiation factor (BCDF) was purified to homogeneity by sequential filtration and chromatography of culture supernatants from TCL-Na1 cells on an AcA34 gel column and then on a Mono P column with fast protein liquid chromatography and reversed-phase HPLC. A 5300-fold enrichment in specific activity of BCDF with about 25% recovery was attained. The homogeneity of purified BCDF was evidenced by the following: (i) the specific activity was 1.7 X 10(7) units/mg of protein, (ii) only two bands, Mr 19,000 and 21,000, were identified by NaDodSO4/PAGE under reduced as well as nonreduced conditions, and (iii) BCDF activity was recovered from the gel after NaDodSO4/PAGE in the fractions corresponding to protein bands of Mr 19,000 or 21,000. Purified BCDF induced Ig secretion in Epstein-Barr virus-transformed cell lines; as little as 3 pM gave 50% of the maximum reaction achieved by 30-80 pM BCDF. Purified BCDF induced Ig production in activated B cells without any effect on cell growth. Purified BCDF did not show any activity of interleukin 1 or 2, B-cell stimulatory factor (BSF)p-1, B-cell growth factor II (BCGF-II), or interferon. Since BCDF was isolated and characterized as described, we propose that the BCDF that induces the final differentiation of B cells into high-rate Ig-secreting cells be designated BSFp-2. 相似文献
88.
T Hirano P Prunet H Kawauchi A Takahashi T Ogasawara J Kubota R S Nishioka H A Bern K Takada S Ishii 《General and comparative endocrinology》1985,59(2):266-276
A highly specific radioimmunoassay (RIA) for the measurement of prolactin (PRL) in the plasma and pituitary of salmonid fishes was developed using a rabbit antiserum to chinook salmon (Oncorhynchus tschawytscha) PRL. The PRLs purified from chinook salmon and chum salmon (O. keta) pituitaries showed exactly the same competitive inhibition curves in the RIA, regardless of iodination of either hormone. The displacement curves for pituitary extracts and plasma from several salmonids, including chum, coho, and amago salmon, rainbow trout, and Japanese charr, were parallel to the salmon PRL standard, whereas those from the eel, goldfish, carp, and tilapia showed negligible cross-reactivity. Negligible cross-reactivity was also seen with plasma from hypophysectomized rainbow trout or coho salmon. None of the mammalian PRL or growth hormone (GH) preparations, bullfrog PRL, or presumptive chum salmon "gonadotropin" and eel "PRL" cross-reacted in the PRL RIA. Presumptive chum salmon GH showed less than 0.05% cross-reactivity. The RIA sensitivity was less than 0.1 ng of the salmon PRL standard per milliliter. The immunoreactive plasma PRL levels in mature chum salmon were below 1 ng/ml in seawater. The plasma PRL in females increased to about 8 ng/ml 1 day after transfer to fresh water, and high levels (2-4 ng/ml) were maintained during 3-7 days after the transfer. In contrast, when males were transferred to fresh water, an increase in plasma PRL was seen only 1 day after the transfer. A significant decrease in plasma osmolality was observed in both males and females after transfer to fresh water. No change was observed either in plasma PRL or osmolality, when fish were transferred from seawater to seawater. 相似文献
89.
T Okuyama K Saito A Hirano A Takahashi T Inagaki S Inamura Y Nakazato 《No shinkei geka. Neurological surgery》1999,27(5):447-452
A rare case of glioblastoma fed by meningeal branches of the external carotid artery was reported. A 63-year-old female was transferred to our hospital suffering from gait disturbance and dysarthria. CT and MRI revealed brain tumor and paratumoral hemorrhage with a large cyst that was heterogeneously enhanced and existed in the right fronto-temporal region. Right external carotid arteriography demonstrated the tumor stain markedly fed by the right middle meningeal artery and the accessory meningeal artery. Subtotal removal operation was carried out uneventfully using the right fronto-temporal craniotomy. The histological diagnosis was glioblastoma. After the operation the patient was in good condition, and was transferred to another hospital for the purpose of the synchronized chemoradiotherapy. It is well known that any glioma invades the meninges. However, we rarely encountered an intra-axial glioma fed by a meningeal blood supply. A meningeal-invaded glioma may make difficult its differentiation from meningioma. We concluded that there is necessity for close examination of the intra-axial brain tumors invaded and fed by meningeal blood supply. 相似文献
90.
Tomita M Shimokawa I Maeda H Higami Y Kawahara T Ikeda T Hirano T 《Calcified tissue international》1999,64(3):259-262
We investigated the effects of dietary restriction (DR), an experimental intervention known to suppress several strain-specific
diseases, on the prevalence of osteonecrosis of the caput femoris in spontaneously hypertensive rats (SHR). At 6 weeks of
age, the food intake of DR rats was restricted to 65% of the mean intake of control rats fed ad libitum (AL). Acute osteonecrosis of the caput femoris without reparative tissue response (RTR) was observed at 10 and 15 weeks in
both DR and AL groups; no such acute lesion was seen at 20 and 30 weeks. The prevalence of osteonecrosis, osteonecrosis with/without
reparative tissue response was significantly reduced in DR rats at 15 and 20 weeks, but not at 10 weeks. DR reduced the body
weight by 30% and the length of the femur by 10%. Ossification of the caput femoris, known to be delayed in AL rats compared
with Wistar Kyoto rats, was also restored by DR. Our results showed that dietary restriction reduced the prevalence of osteonecrosis
and modulated the mechanical factors involved in the lesion. They also indicate that utilization of dietary restriction is
a useful research tool for investigating the underlying mechanisms of osteonecrosis of the caput femoris in SHR.
Received: 4 March 1997 / Accepted: 9 July 1998 相似文献