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61.
Keiji Uchikawa 《Vision research》1983,23(1):53-58
Purity discrimination thresholds (Δp) were measured with successive (SOA = 3 sec) and simultaneous (SOA = 0 sec) comparison methods for seven dominant wavelengths: 410, 480, 500, 530, 570, 600 and 650 nm. The stimulus duration was 1 sec. The Δp values with the successive comparison method were found to he about 1.5–2.0 times larger than those obtained in the simultaneous case. The degree of purity discrimination deterioration shown in this study is similar to that of wavelength discrimination deterioration previously reported (Uchikawa and Ikeda, 1981, Vision Res.21, 591–595). Saturation shifts of stimuli with the successive comparison method were also observed: these were toward increased saturation direction for most dominant wavelengths. 相似文献
62.
Kohei Notoya Ryoichi Tsukuda Keiji Yoshida Shigehisa Taketomi 《Calcified tissue international》1992,51(Z1):S16-S20
The effects of ipriflavone (IP) (10–5 M) on bone formation were studied in stromal cells from the femoral bone marrow of young adult rats cultured for 21 days in the presence of -glycerophosphate and dexamethasone. Stereoscopic microscopy showed nodule formation after 14 days of culturing, and both the number and the size of the nodules increased with time. The alizarin-red-stained calcified area in the nodules in the IP group was nearly 4 times as large as that in the control after 21 days. Light and electron microscopy revealed the presence of many osteoblast-like cells with developed rough endoplasmic reticulum and Golgi apparatus in the nodules in the control group after 14 days, and a collagenous fibril network was seen among the cells. After 21 days, calcification of the dense collagenous fibril network and bone matrix-like tissue were observed in many nodules, resulting in the formation of bone-like tissue containing osteocyte-like cells. In the IP group, the collagenous fibril network area in the nodules was greater than that in the control after 14 days, and a further increase in both the dense collagenous fibril network area and calcified bone-like tissue area was observed after 21 days. These findings indicate that IP stimulates bone-like tissue formation in the rat bone marrow stromal cell culture, suggesting that the promotion of collagen production by osteoblasts is involved in the stimulation of bone-like tissue formation by IP. 相似文献
63.
64.
Fujii K; Fukutomi T; Tsuda H; Akashi-Tanaka S; Nanasawa T; Kanai Y; Muramatsu Y 《Japanese journal of clinical oncology》1998,28(1):47-49
A 44-year-old woman presented with a right huge axillary mass. Both
mammography and ultrasonography revealed a primary cancer of 2.8 cm maximum
diameter in the right breast and metastases in the axillary lymph nodes,
both being confirmed by aspiration cytology as ductal carcinoma. Right
standard radical mastectomy with level III axillary lymph node dissection
was carried out. Pathologically, the tumor was diagnosed as ductal
carcinoma in situ with microinvasion (DCISM), histologic grade 3. The area
of stromal invasion measured 1 mm at its widest point. Sixteen of the 17
resected axillary lymph nodes contained metastases, including six level III
lymph nodes. Immunohistochemical studies of the tumor revealed
overexpression of p53 protein, but not that of c-erbB-2 protein. The
frequency of lymph node metastases from DCISM is reported to be very low.
Therefore, the present case with extensive involvement of level III lymph
nodes was unusual.
相似文献
65.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum 总被引:1,自引:2,他引:1
Hiroyuki Uchida Hiroshi Ando Keiji Maruyama Hiroshi Kobayashi Hiroshi Toda Hiroshi Ogawa Takachika Ozawa Yasuhide Matsuda Haruhiko Sugimura Takashi Kanno Shozo Baba 《Cancer science》1998,89(3):299-306
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs. 相似文献
66.
K. Aridome S. Takao T. Kaname K. Kadomatsu S. Natsugoe F. Kijima T. Aikou T. Muramatsu 《British journal of cancer》1998,78(4):472-477
Midkine (MK) is a growth factor identified as a product of a retinoic acid-responsive gene. A truncated form of MK mRNA, which lacks a sequence encoding the N-terminally located domain, was recently found in cancer cells. We investigated the expression of the truncated MK mRNA in specimens of 47 surgically removed human gastrointestinal organs using polymerase chain reaction. Truncated MK was not detected in all of the 46 corresponding non-cancerous regions. On the other hand, this short MK mRNA was expressed in the primary tumours in 12 of 16 gastric cancers, 8 of 13 colorectal carcinomas, five of nine hepatocellular carcinomas, two of two oesophageal carcinomas and one ampullary duodenal cancer. In addition, truncated MK was detectable in all of the 14 lymph node metastases but in none of three metastatic sites in the liver, suggesting that truncated MK mRNA could become a good marker of nodal metastases in gastrointestinal tract. 相似文献
67.
Nitric oxide synthase activity and inhibition after neonatal hypoxia ischemia in the mouse brain 总被引:7,自引:0,他引:7
Muramatsu K Sheldon RA Black SM Täuber M Ferriero DM 《Brain research. Developmental brain research》2000,123(2):119-127
Despite the emergence of therapies for hypoxic-ischemic injury to the mature nervous system, there have been no proven efficacious therapies for the developing nervous system. Recent studies have shown that pharmacological blockade of neuronal nitric oxide synthase (nNOS) activity can ameliorate damage after ischemia in the mature rodent. We have previously shown that elimination of nNOS neurons, either by targeted disruption of the gene or by pharmacological depletion with intraparenchymal quisqualate, can decrease injury after hypoxia-ischemia. Using a simpler pharmacological approach, we studied the efficacy of a systemically administered NOS inhibitor, 7-nitroindazole, a relatively selective inhibitor of nNOS activity. Using multiple doses and concentrations administered after the insult, we found that there was only a trend for protection with higher doses of the drug. A significant decrease in NOS activity was seen at 18 h and 5 days in the cortex, and at 2 h and 18 h in the hippocampus after the hypoxia-ischemia. nNOS expression decreased and remained depressed for at least 18 h after the insult. When nNOS expression was normalized to MAP2 expression, a decrease was seen at 18 h in the cortex and at 2 and 18 h in the hippocampus. These data suggest that further inhibition of NOS activity at early timepoints may not provide substantial benefit. At 5 days after the insult, however, NOS activity and normalized nNOS expression returned to baseline or higher in the hippocampus, the region showing the most damage. These data suggest that delayed administration of nNOS inhibitor after hypoxic-ischemic injury might be beneficial. 相似文献
68.
69.
Keiji Inoue Takashi Karashima Satoshi Fukata Asuka Nomura Chiaki Kawada Atsushi Kurabayashi Mutsuo Furihata Yuji Ohtsuki Taro Shuin 《Clinical cancer research》2005,11(18):6669-6677
PURPOSE: Transitional cell carcinoma (TCC) of the urinary tract is a chemosensitive tumor. Most deaths from TCC of the urinary tract are caused by metastasis, which is resistant to conventional chemotherapy. Frequent sites of metastases from TCC of the urinary tract are regional lymph nodes, liver, lung, and bone. Of these distant metastases, bone metastasis is consistently resistant to cisplatin-based conventional chemotherapy. Therefore, in this study, we investigated whether or not a newly developed minodronate, YM529, could prevent osteolytic bone metastasis of human TCC and also enhance the effect of docetaxel in a bone tumor model of athymic nude mice. EXPERIMENTAL DESIGN: In the present study, we evaluated the effect of in vitro treatment with minodronate and/or docetaxel on the proliferation by cell count, the induction of apoptosis by terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and the biological activity of osteoclast by pit formation assay in human bladder cancer cell line, UMUC-14, and mouse osteoclast cells. In vivo, we examined the effect of minodronate in a bone tumor model of athymic nude mice, in which the percutaneous intraosseal injection in the tibia of UMUC-14, leads to osteolytic bone tumor, as a bone metastasis model. To examine whether or not minodronate could inhibit tumorigenicity and enhance the effect of the chemotherapeutic agent, docetaxel, we gave minodronate i.p. and/or docetaxel i.p. to nude mice 3 days after an intraosseal tumor implantation. Moreover, proliferation and the induction of apoptosis of cancer cells and osteoclasts in bone tumors were determined by immunohistochemistry and the TUNEL assay. RESULTS: In vitro: In vitro treatment with docetaxel inhibited proliferation and resorption pit-forming activity and induced apoptosis of mouse osteoclast cells and UMUC-14 cells. In vitro treatment with minodronate inhibited proliferation and activity and induced apoptosis of mouse osteoclast cells but not UMUC-14 cells. The treatment with minodronate enhanced the inhibition of proliferation and activity by docetaxel in osteoclasts. In vivo: In vivo combination therapy with docetaxel and minodronate significantly reduced the tumor incidence compared with the control (P < 0.05) and also growth of intraossal TCC in athymic nude mice compared with the control (P < 0.001), single therapy with docetaxel (P < 0.01), and minodronate (P < 0.05). Drug-induced body weight loss was not significantly different in any treatment group. Therapy with minodronate significantly enhanced inhibition of proliferation by docetaxel in osteoclasts of bone tumors compared with the control (P < 0.01), single therapy with docetaxel (P < 0.01), and minodronate (P < 0.05). CONCLUSIONS: These studies indicate that combination therapy with minodronate and docetaxel may be beneficial in patients with bone metastasis of human TCC in the urinary tract. 相似文献
70.
Maruichi M Takai S Sugiyama T Ueki M Oku H Sakaguchi M Okamoto Y Muramatsu M Ikeda T Miyazaki M 《Experimental eye research》2004,79(1):111-118
Chymase is a chymotrypsin-like serine protease contained in the secretory granules of mast cells. Recently, we reported that chymase activity and the number of chymase-positive mast cells in conjunctival tissues were significantly increased during the wound healing process in a hamster model of glaucoma surgery. However, it has been unclear the role of chymase on conjunctival scarring. In the present study, we evaluated the effect of dog chymase on cell proliferation of fibroblasts established from canine Tenon's capsule and the effect of a chymase inhibitor on scarring in a canine conjunctival flap model. After a fibroblast cell culture was established from canine Tenon's capsules, the fibroblasts were incubated in the presence of dog chymase (5-20 ng ml(-1)). Cell proliferation was evaluated by bromodeoxyuridine incorporation. In a canine conjunctival flap model, a sponge treated with a chymase inhibitor, Suc-Val-Pro-Phe(P)(OPh)(2), or placebo was placed in between the conjunctiva and sclera and the conjunctival incision was closed. One week after the surgery, adhesion degree was assessed, and chymase activities in the conjunctival lesion and in the areas of the conjunctiva and sclera were measured. In cultured canine Tenon's capsule fibroblasts, dog chymase significantly increased cell proliferation, and this chymase-dependent proliferation was completely suppressed by the chymase inhibitor. In the canine surgical model, chymase activity in placebo-treated eyes was significantly increased compared to control eyes, while it was significantly decreased by treatment with the chymase inhibitor. Scores for adhesion degree in the chymase inhibitor-treated eyes were significantly decreased in comparison with those in placebo-treated eyes. The conjunctival area in the chymase inhibitor-treated eyes was also suppressed to 52.6% compared with that in placebo-treated treated eyes. In conclusion, chymase stimulates proliferation of fibroblasts derived from canine Tenon's capsule and chymase may play an important role in scarring after glaucoma surgery. 相似文献