全文获取类型
收费全文 | 65622篇 |
免费 | 3201篇 |
国内免费 | 425篇 |
专业分类
耳鼻咽喉 | 653篇 |
儿科学 | 1183篇 |
妇产科学 | 957篇 |
基础医学 | 8741篇 |
口腔科学 | 2109篇 |
临床医学 | 4494篇 |
内科学 | 15884篇 |
皮肤病学 | 1566篇 |
神经病学 | 4691篇 |
特种医学 | 2454篇 |
外科学 | 11335篇 |
综合类 | 341篇 |
一般理论 | 3篇 |
预防医学 | 1938篇 |
眼科学 | 1105篇 |
药学 | 4124篇 |
中国医学 | 165篇 |
肿瘤学 | 7505篇 |
出版年
2023年 | 286篇 |
2022年 | 677篇 |
2021年 | 1394篇 |
2020年 | 696篇 |
2019年 | 1021篇 |
2018年 | 1360篇 |
2017年 | 1035篇 |
2016年 | 1199篇 |
2015年 | 1278篇 |
2014年 | 1720篇 |
2013年 | 2098篇 |
2012年 | 3360篇 |
2011年 | 3828篇 |
2010年 | 2131篇 |
2009年 | 1852篇 |
2008年 | 3331篇 |
2007年 | 3617篇 |
2006年 | 3499篇 |
2005年 | 3722篇 |
2004年 | 3607篇 |
2003年 | 3539篇 |
2002年 | 3565篇 |
2001年 | 1559篇 |
2000年 | 1666篇 |
1999年 | 1602篇 |
1998年 | 952篇 |
1997年 | 718篇 |
1996年 | 710篇 |
1995年 | 625篇 |
1994年 | 548篇 |
1993年 | 504篇 |
1992年 | 994篇 |
1991年 | 931篇 |
1990年 | 853篇 |
1989年 | 848篇 |
1988年 | 813篇 |
1987年 | 763篇 |
1986年 | 766篇 |
1985年 | 672篇 |
1984年 | 526篇 |
1983年 | 431篇 |
1982年 | 236篇 |
1981年 | 239篇 |
1979年 | 396篇 |
1978年 | 273篇 |
1977年 | 227篇 |
1975年 | 220篇 |
1974年 | 240篇 |
1973年 | 229篇 |
1969年 | 231篇 |
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
81.
Blocking effect of 1389-S on the sodium current in isolated guinea-pig ventricular myocytes 总被引:2,自引:0,他引:2
I Hisatome S Matsuoka J Miyamoto M Sawaguchi H Omodani S Osaki H Kotake H Mashiba R Sato 《European journal of pharmacology》1990,179(3):447-451
Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation. 相似文献
82.
Kazushi Kishi Taizo Takeuchi Tetsuo Sonomura Masashi Kimura Keisuke Kita Morio Sato Masaki Terada 《Cardiovascular and interventional radiology》1997,20(1):63-66
In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping
a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile
introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer. 相似文献
83.
Imura Akihiro; Hori Toshiyuki; Imada Kazunori; Kawamata Shin; Tanaka Yuetsu; Imamura Sadao; Uchiyama Takashi 《Blood》1997,89(8):2951-2958
84.
Soroku Doko M.D. F.I.C.A. Tatsuki Katsumura M.D. F.I.C.A. Takashi Fujiwara M.D. Hiroshi Inada M.D. Hisao Masaki M.D. 《The International journal of angiology》1995,4(1):55-60
One hundred and thirty-four patients with vasoocclusive diseases were retrospectively tested for three kinds of antiphospholipid antibody (aPL). The mean age at onset of the disease in 58 patients with aPL was 43 years old. Seventeen, 11, and 9 patients were positive for the aCL IgA, IgM, and IgG isotypes, respectively. The rates of anti-phospholipid syndrome (APS) in patients with arterial (n=94), venous (n= 31), or both arterial and venous (n=9) occlusion were 45%, 29%, and 78%, respectively.The rates of APS in patients with autoimmune disease (n=13), thromboangiitis obliterans (TAO) (n= 36), arteriosclerosis obliterans (ASO) with lower leg involvement (n=8) or aortic arch syndrome (n=5), Raynaud's syndrome (n=15), aortitis syndrome (n= 13), ischemic heart disease (IHD) with young onset (n =12), and bilateral leg deep venous thrombosis (DVT) (n=10) were 77%, 46%, 13%, 80%, 40%, 62%, 33%, and 70%, respectively. The cumulative patency rate for reconstructive surgery in patients (n=13) with aCL was found to be considerably lower than that in those without aCL (n=13). From these results it was concluded that IgA was the most valuable aCL isotype for the diagnosis of APS and that aPL should be examined in patients with double-vessel occlusion, autoimmune disease, bilateral leg DVT, aortic arch syndrome, TAO, Raynaud's syndrome, or IHD with young onset. Furthermore, prophylaxis for graft failure is more strongly recommended for patients with aCL than for those without it. 相似文献
85.
K Sugino Y Kure R Shiraishi H Iwasaki H Sato Y Kumamoto A Matsumoto 《Nihon Geka Gakkai zasshi》1990,91(8):923-930
Recently, mean span of life has been prolonged, and extensive operations are performed on aged patients. However, there are cases which have a difference between their chronological and actual ages. Bone mineral content (BMC) decreases with age and the decrease in BMC might suggest deterioration of immunological competence as observed in osteoporosis. Whether BMC can be an index for evaluation of geriatric patients' actual age from the aspect of immunological competence was investigated. Subjects were 54 cases aged more than 60. Twenty-one healthy young males and females were enrolled as the control group. Quantitative CT is used for assessment of BMC. The value obtained by dividing BMC by the standard BMC of the same age and sex, was defined as BMC index. BMC indices of normal BMC group were more than 0.8 and those of decreased BMC group were less than 0.8. Some immunological markers were investigated. Lymphocyte subset OKT3+ was reduced and juvenile lymphocytes expressed by OKT6+ and OKT3+-(OKT4+ + OKT8+) increased (corrected). Increased in juvenile lymphocyte and decrease in lymphocyte blast transformation and competence of generating interleukin 2 were observed in decreased BMC group. BMC is useful as preoperative evaluation for geriatric operative cases and patients of BMC index below 0.8 need to be paid attention to postoperative infection. 相似文献
86.
The effect of external gamma-irradiation on the digestive function of rat alveolar macrophages (AM) was studied by using the in vitro assay system, where the 59Fe release from AM engulfing 59Fe-iron hydroxide colloid was measured as an indicator of their digestive capability. Graded doses of gamma-irradiation up to 100 Gy had no effect on the extracellular release of 59Fe in AM cultured at 4 and 37 degrees C for 8-72 hrs postirradiation. When 10 mM Ca-DTPA was added to the culture medium, the 59Fe release was slightly depressed by irradiation at a dose of 30 Gy. It is apparent from these results that gamma-irradiation had no effect on the 59Fe transfer between cell and medium, and little effect on the catabolism of 59Fe-colloid in rat AM. 相似文献
87.
Takashi Ito Kazuo Shimamura Kiyoshi Shoji Akira Akatsuka Yasuyoshi Kiryu Norikazu Tamaoki Yoshiyuki Osamura 《Virchows Archiv : an international journal of pathology》1993,422(6):487-490
A rare case of urinary bladder carcinoma with granulocyte colony stimulating factor (G-CSF) production was reported. In an 83-year-old female, marked neutrophilia in the peripheral blood decreased from 132,500/mm3 to 3,300/mm3 after tumour resection. The tumour was a transitional cell carcinoma. The serum G-CSF level reduced from 238 pg/ml pre-operatively to normal (60 pg/ml) after the operation. Immunohistochemical investigation of the resected tumour with monoclonal antibody specific for G-CSF revealed positive staining in the carcinoma cells, confirming G-CSF secretion. 相似文献
88.
N. Inotsume M. Nishimura M. Nakano S. Fujiyama K. Sagara T. Sato K. Matsushita Y. Imai H. Matsui 《European journal of clinical pharmacology》1990,38(3):313-314
Summary The effect of haemodialysis on the pharmacokinetics of oral famotidine has been studied in five elderly anuric patients. Famotidine 20 mg was administered in a cross-over design to patients on and not on haemodialysis.The elimination rate constant of haemodialysis (k) was 4.6-fold larger than the systemic elimination rate constant (ke). Although the mean maximum serum concentration of famotidine during haemodialysis (141.5 ng·ml–1) was not significantly lower than that without haemodialysis (195.6 ng·ml–1), the AUC up to 5 h during haemodialysis was significantly decreased to 58.1% of the value without it.The data suggest that famotidine is dialysable by haemodialysis. 相似文献
89.
Masatoshi Chiba Takashi Shigihara Seishi Echigo Teiichi Teshima 《Journal of bone and mineral metabolism》1990,8(3):24-29
Summary In this study, we examined histologically the effect of a bone morphogenetic protein (BMP) derived from bovine tooth on the
periosteum. Supraperiosteal injection of crude BMP into femurs of Wistar rats (28 day old) resulted in periosteal cell proliferation
with subsequent bone and cartilage formation. Moreover, proliferating periosteal cells migrated into injected BMP, and formed
both cartilage and bone. These observations show that exogenous BMP stimulates mesenchymal cells of the periosteum to proliferate
and differentiate into osteoblasts, and therefore BMP may be one of factors which are involved in differentiation of osteoblasts
in the periosteum. 相似文献
90.
Takashi Shuto Yutaka Ohtsubo Ken'ichi Sekido Hiroko Iwamoto Isao Yamamoto 《Child's nervous system》1996,12(2):107-109
We report the case of an infant with a cerebellar astrocytoma that showed marked calcification within only 6 months. In general, only slow-growing tumors tend to calcify. To our knowledge, no other case of such rapid calcification in cerebellar astrocytoma has been reported. 相似文献