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1.
磺胺噻二嗪硫酮衍生物的合成及其抑菌活性 总被引:1,自引:0,他引:1
利用药物化学骈合原理设计并合成了一系列新的3,5-二取代1,3,5-噻二嗪-2-硫酮类化合物,其结构经红外光谱,紫外光谱及元素分析证实,抑菌活性试验显示了良好的抑菌活性。 相似文献
2.
2,7,12,18-四甲基-13,17-二(3-羟基丙基)卟啉的合成及其光敏化活性 总被引:5,自引:0,他引:5
由氯化高铁次卟啉经脱铁、酯化、还原合成了光敏剂2,7,12,18-四甲基-13,17-二(3-羟基丙基)卟啉,并测定其光敏活性 相似文献
3.
The crystal structures of the 1:1 complexes methylguanidinium benzylhydrogenmalonate, (C2N3H8)+(C10H9O4)?, MGD.BMAL, and methylguanidinium ethylhydrogenmalonate, (C2N3H8)+(C5H7O4)?, MGD.EMAL, and of the 2:1 complex methylguanidinium sulfate, (C2N3H8)2SO4, have been determined from three-dimensional X-ray data. For MGD.BMAL, the complex crystallizes in the triclinic space group P with two formula units in a cell of dimensions a = 6.277(5), b = 8.470(3), c = 13.191(6)Å, α= 91.01(1), β= 99.64(9), γ= 90.83(5)°. The structure has been refined to a final value of R = 0.061 based on 1511 intensities. The MGD.EMAL complex is also triclinic, space group P with two molecules in a cell of dimensions a = 9.254(7), b = 9.625(6), c = 6.778(2) Å, α= 109.6(1), β= 100.8(1), γ= 62.7(1)Å. The crystals of this compound are of low quality, and the final value is R = 0.109 based on 706 intensities. (MGD)2SO4 is orthorhombic, space group P212121, with four molecules in a cell of dimensions a = 7.100(4), b = 12.151(3), c = 13.108(2) Å. Refinement has converged to R = 0.054 based on 907 data. All three crystals exhibit extensive interionic hydrogen bonding. The hydrogen bonding in MGD.BMAL includes a Type B interaction and a Type 1 interaction, the latter being a pairwise interaction from both amino nitrogen atoms on the cation to two carboxylate oxygen atoms from the two different carboxylate groups in an anion. In MGD.EMAL, the anion participates in both a Type A and a Type B pairwise interaction with two neighboring cations. The possible implications of the hydrogen bonding patterns in these two compounds for the role of arginyl side chains in protection of γ-carboxyglutamate residues from decarboxylation are discussed. 相似文献
4.
Murasaki Mitsukuni Miura Sadanori 《Progress in neuro-psychopharmacology & biological psychiatry》1992,16(6)
Mitsukuni Murasaki and Sadanori Miura: The Future of 5-HT1A Receptor Agonists. (Aryl-Piperazine Derivatives) Prog. Neuro- Psychopharmacol-& Biol Psychiat, 1992, 16(6): 833–845.
- 1. 1. At present the dominant position among anti-anxiety medications has changed from meprobamate to the benzodiazepine derivatives.
- 2. 2. In order to avoid benzodiazepine's (BZ) undesirable side effects such as impairment of psycho-motor function, memory impairment, low dose dependence and withdrawal symptoms, a third generation anxiolytic agent, buspirone, the focus of the aryl-piperazine group of anti-anxiety agents, has been introduced recently.
- 3. 3. Aryl-piperazine derivatives work as 5-HT1A receptor partial agonists and are known as serotonin normalizers.
- 4. 4. Therefore, they are expected to have not only an anxiolytic function but also an anti-depressant effect as well.
- 5. 5. A characteristic of the aryl-piperazine derivatives is that they have no sedative and muscle relaxant effects, and they do not have BZ's undesirable side-effects, especially in regard to withdrawal symptoms. However they have a rather weak anxiolytic action and a slow onset of action.
- 6. 6. Aryl-piperazine derivatives will not take the place of BZ, but the use of BZ and buspirone as bridge medications, making the most of the strong points of both, can be proposed as a way to compensate for their respective disadvantages.
Keywords: aryl-piperazine derivatives; future of new anxiolytics; 5-HT1A receptor agonist; nonbenzodiazepine anxiolytic 相似文献
5.
It was previously proposed that an immunological cross-reaction between two denatured proteins is evidence for an homology betweeen their amino sequence (Arnon &; Maron, 1971; Arnheim et al., 1971) and that detection of such a cross-reaction could then be a rapid method to detect sequence homologies (Zakin et al., 1978). In order to test the possibilities of such a methodology, using proteins of known structure, glyceraldehyde 3-phosphate dehydrogenases from different sources are compared by immunochemical techniques. The antibodies raised against the native enzyme from E. coli K 12 can only recognize the homologous antigen, the glyceraldehyde 3-phosphate dehydrogenase from B. stearothermophilus and to a lesser extent that from halibut. In contrast, the antibodies raised against the denatured enzyme from E. coli K 12 can recognize the glyceraldehyde 3-phosphate dehydrogenases from man, ostrich, chicken, sturgeon, halibut, lobster and yeast, when in their denatured state. The present results show unambiguously that through exposure of buried sequences, the immunochemical detection of sequence homologies among proteins is more discriminating when unfolded proteins are used, rather than native ones. It is also proposed that the use of denatured proteins both as immunogens and antigens would be a useful tool in studying biochemical evolution. 相似文献
6.
The involvement of glutamatergic transmission in the mechanism of movement disorders induced by reversive rotation of white mice 总被引:1,自引:0,他引:1
The ability of the selective non-competitive NMDA receptor blocker MK-801 and a series of new glutamate antagonists—the adamantane
derivatives IEM-1754 and IEM-1857 and phencyclidine (IEM-1925)—to prevent movement disorders induced by reversive rotation
in mice was studied. I.p. MK-801 at a dose of 0.15 ml and IEM-1754 at a dose of 5.0 mg/kg prevented the development of akinesia
in response to reversive rotation, as effectively as scopolamine, a known agent which provides effective prophylaxis for movement
diseases. IEM-1857, the quaternary analog of IEM-1754, was not effective. IEM-1925 significantly increased the responses of
mice to reversive rotation, possibly because of its high activity in relation to other subtypes of glutamate receptors. These
data provide evidence for the involvement of glutamatergic transmission in the mechanism of movement disorders of vestibular
origin.
Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 85, No. 4, pp. 497–501, May, 1999. 相似文献
7.
Gary T. Shearman Rüdiger Schulz Peter W. Schiller Albert Herz 《Psychopharmacology》1985,85(4):440-443
Rats were trained in a two-lever food-reinforced procedure to discriminate between the effects of saline and the opioid kappa receptor agonist ethylketocyclazocine. After acquisition of this discrimination, generalization tests with opioid peptides such as -endorphin, -neoendorphin, dynorphin A and some dynorphin-derived peptides were conducted. The rats dose-dependently generalized the effects of intracerebroventricularly injected ethylketocyclazocine but not -endorphin, -neoendorphin, dynorphin A1–8, dynorphin A1–13, D-Cys2-L-Cys5-dynorphin A1–13 or dynorphin A.
D-Cys2-L-Cys5-dynorphin A1–13, in contrast to dynorphin A itself, dose-dependently caused analgesia and catatonia that was reversible with naloxone. Studies into the receptor preference of this derivative, using the technique of selective tolerance, revealed that this dynorphin derivative is almost devoid of kappa-receptor activity. 相似文献
8.
M. Vasse P. Protais J. Costentin J. -C. Schwartz 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(2):108-116
Summary Among four stereotyped manifestations that can be simultaneously quantified in mice treated with apomorphine (APO), two of them (climbing and sniffing) emerge at low APO dosages (below 1 mg/kg) whereas licking and sniffing require APO dosages above 6 mg/kg. However, in mice pretreated (either i.p. or i.c.v.) with sulpiride (especially the levo isomer) or (±)amisulpride in moderate dosage stereotyped licking and sniffing are elicited by APO in much lower dosage (0.75 mg/kg). As a consequence, in mice pretreated with these benzamide derivatives and receiving 0.75 mg/kg APO, a biphasic effect was observed: licking and gnawing progressively appear at low dosages, whereas they are progressively abolished at higher dosages.This potentiation of the effects of APO by (±)amisulpride is even more obvious (maximal scores increased) with larger test-doses of the dopamine agonist (up to 5 mg/kg). Amisulpride also allows the emergence of the two stereotyped behaviours in mice receiving other dopamine agonists in subthreshold dosages (Dipropyl 5,6-ADTN, dexamphetamine or cocaine). The potentation of APO is still observed after dopamine depletion by reserpine and -methylparatyrosine, whereas that of dexamphetamine is abolished. In contrast with the benzamide derivatives, haloperidol does not potentiate at any dosage the effect of APO but, at 0.15 mg/kg, suppresses licking and gnawing elicited by 0.75 mg/kg APO in mice pretreated with 6.25 mg/kg amisulpride or veralipride.Among a series of dopamine antagonists belonging to various chemical classes, only a number of discriminant benzamide derivatives (DBD), previously shown to differentially antagonise several APO-induced behavioural manifestations in rats (sulpiride, amisulpride, tiapride, sultopride, DO 701, LUR 2366 but not metoclopramide) potentiate APO (0.75 mg/kg) regarding licking and gnawing. In contrast, potentiation is not observed, even for a higher test dose of APO, with haloperidol, thioproperazine, pimozide, mezilamine, thioridazine or metoclopramide at any dosage tested.For the various DBD, the two stereotyped behaviours emerge at dosages at which climbing starts to be inhibited, suggesting that selective blockade of some inhibitory response to APO is responsible for the potentiation. Among other hypothesis the possibility that the peculiar behavioural properties of DBD is related to their differential recognition of two classes of dopaminergic binding sites is discussed. 相似文献
9.
10.
《中国整形与重建外科(英文)》2021,3(2):82-84
Skin grafting, although a relatively classic and well-known technique, still has multiple disadvantages such as secondary contracture of the skin graft, sunken depression, poor elasticity, and color mismatch. Adding adipose tissues significantly improved the graft appearance compared to traditional skin grafting methods. Herein, we report two cases of modified skin graft procedures, both showing positive outcomes. In case 1, a mechanically processed fat-derived product was injected into the lower half of the skin graft area. In case 2, left upper eyelid blepharoplasty was performed, and the orbital fat strip was transferred and placed under the recipient area on the right side. Hair growth was observed only in case 1, whereas the extent of sunken depression was significantly reduced in both cases. Compared to traditional skin grafting methods, adding fat components to the skin graft recipient area improved the appearance and blood supply, together with enhancing the regenerative rate. 相似文献