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991.
Inhibitory Effects of Ginsenoside Rh2 on Tumor Growth in Nude Mice Bearing Human Ovarian Cancer Cells 总被引:1,自引:1,他引:0
Hideyuki Nakata Yoshihiro Kikuchi Takehiko Tode Junko Hirata Tsunekazu Kita Kenji Ishii Kazuya Kudoh Ichiro Nagata Nariyoshi Shinomiya 《Cancer science》1998,89(7):733-740
Ginsenoside Rh2 (Rh2), isolated from an ethanol extract of the processed root of Panax ginseng CA Meyer, inhibits the growth of B16 melanoma cells. This study was designed to evaluate the ability of Rh2 to inhibit growth of human ovarian cancer cells (HRA) in vitro and in nude mouse. Rh2 inhibited proliferations of various established human ovarian cancer cell lines in a dose-dependent manner between 10 and 60 μM in vitro and induced apoptosis at around the IC50 dose. When HRA cells were inoculated s.c. into the right flank of nude mice, all mice formed a palpable tumor within 14 days. Although i.p. administration of Rh2 alone hardly inhibited the tumor growth, when Rh2 was combined with cis-diamminedichloroplatinum(II) (CDDP) the tumor growth was significantly inhibited, compared to treatment with CDDP alone. When mice were treated p.o. with Rh2 daily (but not weekly), the tumor growth was significantly (P<0.01) inhibited, compared to CDDP treatment alone. When Rh2 was combined with CDDP, the degree of tumor growth retardation was not potentiated. The survival time was significantly (P<, we examined whether p.o. administration of Rh2 has a dose-dependent inhibitory effect on the tumor growth. I.p. and weekly administration of CDDP had more potent antitumor activity in the order of 1 mg/kg, 2 mg/kg and 4 mg/kg, whereas p.o. and daily administration of Rh2 (0.4 to 1.6 mg/kg) not only had antitumor activity comparable to that of 4 mg/kg CDDP, but also resulted in a significant increase of the survival. Doses of Rh2 used in this study did not result in any adverse side-effects as confirmed by monitoring hematocrit values and body weight, unlike 4 mg/kg CDDP, which had severe side-effects. It is noteworthy that p.o. but not i.p. treatment with Rh2 resulted in induction of apoptotic cells in the tumor in addition to augmentation of the natural killer activity in spleen cells from tumor-bearing nude mice. Thus, particularly in view of the toxicity of CDDP, Rh2 alone would seem to warrant further evaluation for treatment of recurrent or refractory ovarian tumor. 相似文献
992.
993.
Yusuke Okuyama Akiko Makiyama Tatsuya Okajima Takahiro Suzuki Susumu Nakata Eiji Funatsu Hideki Nakamura Jun Ochiai Satoshi Myojyo Hiroyuki Kimura Nobuaki Yagi Hiromu Kutsumi Hiroko Yashiro Yoshikazu Suyama Sotaro Fujimoto Yohei Hosokawa Nobuyuki Sugeta Hirotomo Otsuka Seiji Shimizu 《Nihon Shokakibyo Gakkai zasshi》2002,99(6):622-625
994.
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996.
A Yabuki H Mishina M Miyazaki M Maeda K Sato S Ishii 《Neurologia medico-chirurgica》1991,31(9):568-574
A cat model of compression ischemia using epidural balloon inflation investigated: 1) the relationship between postischemic cerebral blood flow (CBF) and metabolism and brain swelling, 2) the use of arteriovenous oxygen difference (AVDO2) and electroencephalographic (EEG) frequency band analysis for monitoring CBF and cerebral metabolism, and 3) indications for selecting the therapy. Global ischemia was induced by brain compression, followed by rapid decompression, and AVDO2, CBF, cerebral metabolic rate for oxygen, and EEG were monitored. The animals were divided into delayed brain swelling and no swelling groups. The severity of compression ischemia influenced the recovery of CBF and cerebral metabolism. The AVDO2 and EEG reflected the CBF and cerebral metabolism. These parameters are useful in selecting the therapy for focal brain injury. 相似文献
997.
998.
Novel antigen expression on syngeneic somatic cell hybrids of murine spontaneous mammary tumor cells
T Dei K Masuko H Ishii T Makita T Tachibana 《Journal of the National Cancer Institute》1986,77(2):511-519
Spontaneous mammary carcinoma cells of C3H/He mice were fused with syngeneic L-cells, and two types of hybrid cell clones were obtained. In group A, hybrid cells showed contact inhibition, and parental H-2k and L-antigens were well expressed. Metacentric chromosomes of L-cell origin and estrogen dependency were also well preserved in this group. However, in group B, hybrid cells proliferated to pile up, and the expression of parental antigens, H-2 and L-cell antigens, was strongly suppressed. But, mouse mammary tumor antigens (MM-antigens), which were expressed on ascites mammary tumor cells with hypotetraploidy of C3H/He origin and which were not expressed on both parent cells, were newly expressed. The number of metacentric chromosomes was decreased, and estrogen dependency was lost in this group. The relationship between the expression of MM-antigens and that of H-2 antigens was reciprocal, and tumorigenicity was independent of cellular behavior in vitro and of MM-antigen expression. MM-antigen-positive hybrid cell clones were frequently obtained when tumor cells were fused with metaphase-rich L-cells. 相似文献
999.
S Takeuchi T Miyakawa T Koike R Tanaka H Arai K Sekine R Ishii 《Brain and nerve》1986,38(12):1143-1149
Cerebral blood flow in both hemispheres was studied by the 133Xe inhalation method in 49 patients with cerebral infarction in the unilateral hemisphere. They were classified into three groups by computed tomographic findings as follows; relatively large low density lesion including the cerebral cortex and subcortex (cortical: C group), relatively large low density lesion including the subcortical white matter and basal ganglia (large subcortical: L group), and small low density lesion including the subcortical white matter (small subcortical: S group), respectively. Mean cerebral blood flow (mCBF) in the affected hemispheres was markedly low in C group, moderately low in L group, and slightly low in S group, in all of the examinations. Several cases in C and L groups revealed remarkable changes of mCBF less than one month after the onset. MCBF in both hemispheres was lower in C group than in L and S groups less than one week after the onset. Seven to twelve weeks after the onset, mCBF in the affected hemisphere was lower in C and L groups than in S group, and than in the unaffected hemisphere of C and L groups. There was no difference between mCBF in the affected hemisphere and that in the unaffected hemisphere in most of S group. Sequential changes of mCBF in both hemispheres were divided into seven types in 27 cases, who were examined first less than one week and repeatedly then. However, the sequential changes were classified roughly into two patterns.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
Adhesion of lens capsule to intraocular lenses of polymethylmethacrylate, silicone, and acrylic foldable materials: an experimental study 总被引:13,自引:0,他引:13
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AIMS—To investigate the adhesion characteristics of several intraocular lenses (IOLs) to the simulated and rabbit lens capsule.
METHODS—Adhesive force to bovine collagen sheets was measured in water with polymethylmethacrylate (PMMA), three piece silicone, and acrylic foldable IOLs. In rabbit eyes, phacoemulsification and IOL implantation were performed. Three weeks later, adhesion between the anterior/posterior capsules and IOL optic was tested, and the capsule was examined histologically.
RESULTS—The mean adhesive force to the collagen sheet was 1697 (SD 286) mg for acrylic foldable, 583 (49) mg for PMMA, and 0 mg for silicone IOLs (p=0.0003, Kruskal-Wallis test). Scores (0-5) of adhesion between rabbit anterior capsule and IOL optic were 4.50 (0.55) for acrylic foldable, 3.20 (0.84) for PMMA, and 0.40 (0.55) for silicone IOLs (p=0.004). Scores between rabbit posterior capsule and IOL optic displayed a similar tendency; 4.50 (0.84) for acrylic foldable, 3.00 (1.00) for PMMA, and 0.40 (0.55) for silicone IOLs (p=0.021). Histological observation indicated that the edge of IOL optic suppressed the migration of lens epithelial cells towards the centre of the posterior capsule. This inhibitory effect was most pronounced with acrylic foldable IOL and least with silicone IOL.
CONCLUSIONS—The acrylic foldable IOL adhered to the lens capsule more than the PMMA IOL, and the silicone IOL showed no adhesiveness. These differences seem to play a role in preventing lens epithelial cells from migrating and forming posterior capsule opacification.
Keywords: intraocular lens; lens capsule; posterior capsule opacification; adhesion 相似文献
METHODS—Adhesive force to bovine collagen sheets was measured in water with polymethylmethacrylate (PMMA), three piece silicone, and acrylic foldable IOLs. In rabbit eyes, phacoemulsification and IOL implantation were performed. Three weeks later, adhesion between the anterior/posterior capsules and IOL optic was tested, and the capsule was examined histologically.
RESULTS—The mean adhesive force to the collagen sheet was 1697 (SD 286) mg for acrylic foldable, 583 (49) mg for PMMA, and 0 mg for silicone IOLs (p=0.0003, Kruskal-Wallis test). Scores (0-5) of adhesion between rabbit anterior capsule and IOL optic were 4.50 (0.55) for acrylic foldable, 3.20 (0.84) for PMMA, and 0.40 (0.55) for silicone IOLs (p=0.004). Scores between rabbit posterior capsule and IOL optic displayed a similar tendency; 4.50 (0.84) for acrylic foldable, 3.00 (1.00) for PMMA, and 0.40 (0.55) for silicone IOLs (p=0.021). Histological observation indicated that the edge of IOL optic suppressed the migration of lens epithelial cells towards the centre of the posterior capsule. This inhibitory effect was most pronounced with acrylic foldable IOL and least with silicone IOL.
CONCLUSIONS—The acrylic foldable IOL adhered to the lens capsule more than the PMMA IOL, and the silicone IOL showed no adhesiveness. These differences seem to play a role in preventing lens epithelial cells from migrating and forming posterior capsule opacification.
Keywords: intraocular lens; lens capsule; posterior capsule opacification; adhesion 相似文献