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901.
Ozeki T Chinzei T Abe Y Saito I Isoyama T Mochizuki S Ishimaru M Takiura K Baba A Toyama T Imachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(4):469-474
A transcutaneous energy transmission system (TETS) for artificial hearts and ventricular assist devices uses electrical coupling of power between external and implanted coils. If the position of coils changes relative to each other, the TETS cannot feed the required power of the implanted device. During activity or sleep, the coils may move accidentally. TETS users and the people around them have to pay attention to this because the range of the position where the required power can be fed efficiently is not wide. Therefore, we added functions for the position changes of the coils to the TETS. Regular, cautious, and irregular positions were introduced, and the ranges of them were decided upon in our experiments. The cautious position was determined by the area where the change of the relative position of the coils was relatively small. When the coils were in the cautious position, the circuit was tuned by way of changing the resonant point. This modulation could give good power efficiency in the cautious position. When the coils were in the irregular position, an alarm switch was turned on. These functions ease the restriction of the coil position and give better quality of life (QOL) than do the conventional TETS. 相似文献
902.
Takizawa M Kameyama K Maruyama M Ishida H 《Nihon rinsho. Japanese journal of clinical medicine》2003,61(2):287-291
Loss of bone mineral content has been recognized as one of the chronic complications of type 2 diabetes mellitus, although its mechanism is not fully documented. A negative calcium balance due to both enhanced urinary calcium excretion and decreased intestinal calcium absorption has been occurred because of alteration of vitamin D metabolism and/or decreased parathyroid function. From the view point of bone cell metabolism, osteoblastic bone formation is suppressed by alternation of vitamin D metabolism, hypoparathyroidism, chronic hyperglycemia and insufficient insulin action. On the other hand, osteoclastic bone resorption is rather enhanced. The functional bone uncoupling system between osteoblast and osteoclast in type 2 diabetes mellitus could result in loss of bone density. 相似文献
903.
Takizawa H 《Nihon rinsho. Japanese journal of clinical medicine》2003,61(2):325-329
About 10 years ago, the selection of people with small bone mineral density has begun in each area of Japan. Even if there is a human with small bone density, it is not often possible to carry out the appropriate consultation in the medical institution in the region. It originates the bad cooperation between medical institution and bone measuring organization. In this country, osteoporotic patients are treated with various methods in the department of orthopaedics, medicine and gynaecology. As a result, they are not satisfied with the treatment. Efficiently, cooperation system are necessary in order to treat the human with small bone density. 相似文献
904.
Inoue K Valdez GR Reyes TM Reinhardt LE Tabarin A Rivier J Vale WW Sawchenko PE Koob GF Zorrilla EP 《The Journal of pharmacology and experimental therapeutics》2003,305(1):385-393
Corticotropin-releasing factor (CRF) has been hypothesized to modulate consummatory behavior through the Type 2 CRF (CRF(2)) receptor. However, behavioral functions subserved by the CRF(2) receptor remain poorly understood. Recently, human urocortin II (hUcn II), a selective CRF(2) receptor agonist, was identified. To study the effects of this neuropeptide on ingestive behavior, we examined the effects of centrally infused hUcn II (i.c.v. 0, 0.01, 0.1, 1.0, 10.0 micro g) on the microstructure of nose-poke responding for food and water in nondeprived, male rats. Malaise-inducing properties of the peptide were monitored using conditioned taste aversion (CTA) testing. To identify potential sites of action, central induction of Fos protein expression was examined. hUcn II dose dependently reduced the quantity and duration of responding for food and water at doses lower (0.01-1.0 micro g) than that forming a CTA (10 micro g). Effects were most evident during hours 4 to 6 of the dark cycle. Meal pattern analysis showed that hUcn II potently (0.1 micro g) increased the satiating value of food. Rats ate and drank smaller and shorter meals without changing meal frequency. Rats also ate more slowly. hUcn II induced Fos in regions involved in visceral sensory processing and autonomic/neuroendocrine regulation and resembling those activated by appetite suppressants. hUcn II is a promising neuropeptide for investigating the role of the CRF(2) receptor in ingestive behavior. 相似文献
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908.
Involvement of TGF-beta signal for peritoneal sclerosing in continuous ambulatory peritoneal dialysis 总被引:8,自引:0,他引:8
Naiki Y Maeda Y Matsuo K Yonekawa S Sakaguchi M Iwamoto I Hasegawa H Kanamaru A 《Journal of nephrology》2003,16(1):95-102
BACKGROUND: Functional failure of the peritoneal membrane is the most serious problem in long-term continuous ambulatory peritoneal dialysis (CAPD). Transforming growth factor-beta (TGF-ss) is one of the key mediators of fibrosis in some organs, and is thought to be involved in peritoneal alterations. In this study, we examined the role of TGF-beta1/TGF-ss receptors for human peritoneal mesothelial cells (HPMCs) and fibroblasts, and their interactions in CAPD patients. METHODS: HPMCs were cultured for 48 h in a medium containing normal- dose glucose (7 mM), high-dose glucose (30 mM) and mannitol as an osmotic agent, equal to 30 mM glucose. Cell proliferation was observed using the Tetra Color One assay. The concentration of TGF-beta1 in culture supernatants was measured by enzyme-linked immunosorbent assay (ELISA). The expression of TGF-ss receptor types I and II was observed by flow cytometry. HPMCs and fibroblasts were co-cultured and assayed using transwell inserts in order to identify the effects of the high-concentration glucose solution. RESULTS: HPMC proliferation was inhibited by the high concentration of glucose but not by mannitol. The inhibition was abrogated by the neutralizing antibody for TGF-beta1. TGF-beta1 was induced by a high concentration of glucose but not by mannitol. The expression of both TGF-ss receptors was augmented in culture with the high concentration of glucose but not with mannitol. In the co-culture assay, the number of HPMCs was decreased and fibroblasts were significantly increased in culture with the high concentration of glucose. CONCLUSIONS: A high concentration of glucose induced a large amount of TGF-beta1 and enhanced the expression of TGF-ss receptors. HPMCs were sensitive to TGF-beta1 in response to a high concentration of glucose. These data suggest that TGF-beta1 from HPMCs exposed to a high concentration of glucose down-regulates the proliferation of HPMCs and accelerates peritoneal fibrosis. 相似文献
909.
Tanaka H Nishimaru K Makuta R Hirayama W Kawamura T Matsuda T Tanaka Y Kawanishi T Shigenobu K 《Pharmacology》2003,67(3):157-162
The inotropic action of prostaglandins PGF(2alpha), PGD(2) and PGE(2) on isolated mouse left atria was characterized and compared with the positive inotropic action of acetylcholine, which has previously been shown to be mediated by prostaglandins released from the endocardial endothelium. PGF(2alpha), PGD(2) and PGE(2) produced positive inotropic responses; the time course of the change in contractile force induced by PGF(2alpha) and PGD(2) was about the same as that by acetylcholine, while that by PGE(2) was slower. Fluprostenol and sulprostone, FP and EP receptor agonists, respectively, had positive inotropic effects while BW-245C, a DP receptor agonist, had no effect. AH-6809, a DP receptor antagonist, had no inhibitory effect on the positive inotropic response to PGD(2). Dimethylamiloride, an inhibitor of Na(+)/H(+) exchange, inhibited the positive inotropic response to PGF(2alpha), PGD(2) and acetylcholine, but not PGE(2). Fluorometric pH measurement with carboxy-SNARF-1-loaded atrial myocytes revealed no change in intracellular pH on application of PGF(2alpha). PGF(2alpha) and PGD(2) significantly prolonged the duration of the atrial action potential while PGE(2) had no significant effect. These findings suggest that prostaglandins induce positive inotropic response in mouse atria through FP and EP receptor stimulation and that the former mechanism mediates in part the positive inotropic response to acetylcholine. 相似文献
910.
Kim K Mizunari T Mizutani N Kobayashi S Takizawa K Kamiyama H Murai Y Teramoto A 《Acta neurochirurgica》2006,148(3):353-7; discussion 357
We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass and A3-A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his current presentation, its gradual increase producing visual field disturbances. An A3-A3 side-to-side anastomosis and STA-RA graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful for treating giant or thrombosed aneurysms in the region of the ACoA. 相似文献