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81.
Besides intrinsic determinants of cell growth, epigenetic signals have been proposed to regulate development and maintenance of neurons. Here we provide evidence that cerebral astrocytes contribute significantly to the set of environmental influences that are required for long-term survival of neurons derived from the mammalian central nervous system. Cerebral astrocytes in serum-free culture express diffusible and non-diffusible neuron-supporting signals, including cell-adhesive neurite growth-promoting glycoproteins, diffusible neurotrophic factors as well as membrane-bound molecules that mediate cell contact interactions. The combination and synergistic interaction of these environmental signals markedly enhance the survival of brain neurons. While astroglia-derived cell-adhesive substrates that include a high molecular weight complex consisting of laminin β-chains and proteoglycan (Matthiessen et al., 1989) stimulate neurite outgrowth, they fail to enhance long-term neuronal survival when additional neurotrophic and cell-contact interactions are lacking. Astrocytes release a diffusible neurotrophic activity that, when permanently applied, maintains long-term survival of central neurons in culture. The soluble neurotrophic activity seems to interact synergistically with cell-bound signals which are also required for long-term survival and which are expressed by astrocytes and neurons, but not by fibroblasts. Among neurons from different brain areas, such as hippocampus, cerebral cortex and septum, regional differences in their responsiveness to the astroglial neurotrophic activity have been observed. 相似文献
82.
Per Madsen Hanne L. Olesen Niels H. Secher M. Klokker 《European journal of applied physiology》1995,70(3):246-251
A double-blind paired protocol was used to evaluate, in eight male volunteers, the effects of the endogenous opiate antagonist naloxone (NAL; 0.05 mg· kg–1) on cardiovascular responses to 50° head-up tilt-induced central hypovolaemia. Progressive central hypovolaemia was characterized by a phase of normotensive-tachycardia followed by an episode of hypotensive-bradycardia. The NAL shortened the former from 20 (8–40) to 5 (3–10) min (median and range; (P < 0.02). Control head-up tilt increased the means of thoracic electrical impedance [from 35.8 (SEM 2.1) to 40.0 (SEM 1.8) ; P < 0.01 of heart rate [HR; from 67 (SEM 5) to 96 (SEM 8) beats · min–1, P < 0.02], of total peripheral resistance [TPR; from 25.5 (SEM 3.2) to 50.4 (SEM 10.5)mmHg min 1–1,P < 0.05] and of mean arterial pressure [MAP; from 96 (SEM 2) to 101 (SEM 2)mmHg, P < 0.02]. Decreases were observed in stroke volume [from 65 (SEM 12) to 38 (SEM 9) ml, P < 0.01], in cardiac output [from 3.7 (SEM 0.7) to 2.5 (SEM 0.5) 1 · mint, P < 0.01], in pulse pressure [from 55 (SEM 4) to 37 (SEM 3)mmHg, P < 0.01] and in central venous oxygen saturation [from 73 (SEM 2) to 59 (SEM 4)%, P < 0.01]. During NAL, mean HR increased from 70 (SEM 3); n.s. compared to control) to only 86 (SEM 9) beats · min–1 (P < 0.02 compared to control) and MAP remained stable. The episode of hypotensive-bradycardia appeared as mean control HR decreased to 77 (SEM 7)beats · min–1, TPR to 31.4(SEM 7.7)mmHg · min · 1–1 and MAP to 60 (SEM 5)mmHg (P < 0.01), and the volunteers were tilted supine. Cardiovascular effects of naloxone on central hypovolaemia included a reduced elevation of HR and blood pressures and provocation of the episode of hypotensive-bradycardia. 相似文献
83.
目的探讨烧伤患者中心静脉导管感染的原因并制定有效预防措施。方法对2004年1月~2007年12月烧伤病房158例中心静脉置管患者进行监测,包括导管留置时间、置管部位、穿刺部位皮肤、置管环境及导管的病原学检查结果等。结果引起重度烧伤患者中心静脉导管感染的病原菌中,主要为真菌和表皮葡萄球菌;中心静脉置管感染与导管留置部位、留置时间等原因有关。结论严格遵守无菌操作原则,提高穿刺人员的操作技能,缩短置管时间,并保证置管环境的洁净,是预防中心静脉导管感染的有效措施。 相似文献
84.
中枢神经系统感染患者血清NSE和sICAM-1的改变 总被引:2,自引:0,他引:2
目的 :探讨中枢神经系统感染患者血清中NSE和sICAM 1水平的改变。方法 :采用ELISA法检测了 30例CNS感染的患者和 2 0例正常健康人血清中的NSE和sICAM 1水平。结果 :在CNS感染患者血清中NSE( 12 5 .6 8± 14 .38μg/L)和sICAM 1( 4 48.94± 96 .70μg/L)显著高于正常对照组的NSE( 6 .6 6± 1.2 5 μg/L)和sICAM 1( 2 91.78± 39.18μg/L) ,P <0 .0 1。在CNS感染各组中病毒性脑炎患者的NSE亦显著高于其他各组 ;sICAM 1在CNS感染各组间无显著性差异 ,P >0 .0 5。结论 :提示NSE和ICAM 1可作为CNS损害和感染的监测指标 相似文献
85.
James W. Verbsky Mary K. Hintermeyer Pippa M. Simpson Mingen Feng Jody Barbeau Nagarjun Rao Carlyne D. Cool Luis A. Sosa-Lozano Dhiraj Baruah Erin Hammelev Alyssa Busalacchi Amy Rymaszewski Jeff Woodliff Shaoying Chen Mary Bausch-Jurken John M. Routes 《The Journal of allergy and clinical immunology》2021,147(2):704-712.e17
86.
G. Holstege L. Meiners K. Tan 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,58(2):379-391
Summary Injections of HRP in the nucleus raphe magnus and adjoining medial reticular formation in the cat resulted in many labeled neurons in the lateral part of the bed nucleus of the stria terminalis (BNST) but not in the medial part of this nucleus. HRP injections in the nucleus raphe pallidus and in the C2 segment of the spinal cord did not result in labeled neurons in the BNST. Injections of 3H-leucine in the BNST resulted in many labeled fibers in the brain stem. Labeled fiber bundles descended by way of the medial forebrain bundle and the central tegmental field to the lateral tegmental field of pons and medulla. Dense BNST projections could be observed to the substantia nigra pars compacta, the ventral tegmental area, the nucleus of the posterior commissure, the PAG (except its dorsolateral part), the cuneiform nucleus, the nucleus raphe dorsalis, the locus coeruleus, the nucleus subcoeruleus, the medial and lateral parabrachial nuclei, the lateral tegmental field of caudal pons and medulla and the nucleus raphe magnus and adjoining medial reticular formation. Furthermore many labeled fibers were present in the solitary nucleus, and in especially the peripheral parts of the dorsal vagal nucleus. Finally some fibers could be traced in the marginal layer of the rostral part of the caudal spinal trigeminal nucleus. These projections appear to be virtually identical to the ones derived from the medial part of the central nucleus of the amygdala (Hopkins and Holstege 1978). The possibility that the BNST and the medial and central amygdaloid nuclei must be considered as one anatomical entity is discussed.Abbreviations AA
anterior amygdaloid nucleus
- AC
anterior commissure
- ACN
nucleus of the anterior commissure
- ACO
cortical amygdaloid nucleus
- AL
lateral amygdaloid nucleus
- AM
medial amygdaloid nucleus
- APN
anterior paraventricular thalamic nucleus
- AQ
cerebral aqueduct
- BC
brachium conjunctivum
- BIC
brachium of the inferior colliculus
- BL
basolateral amygdaloid nucleus
- BNSTL
lateral part of the bed nucleus of the stria terminalis
- BNSTM
medial part of the bed nucleus of the stria terminalis
- BP
brachium pontis
- CA
central nucleus of the amygdala
- Cd
caudate nucleus
- CI
inferior colliculus
- CL
claustrum
- CN
cochlear nucleus
- CP
posterior commissure
- CR
corpus restiforme
- CSN
superior central nucleus
- CTF
central tegmental field
- CU
cuneate nucleus
- D
nucleus of Darkschewitsch
- EC
external cuneate nucleus
- F
fornix
- G
gracile nucleus
- GP
globus pallidus
- HL
lateral habenular nucleus
- IC
interstitial nucleus of Cajal
- ICA
internal capsule
- IO
inferior olive
- IP
interpeduncular nucleus
- LC
locus coeruleus
- LGN
lateral geniculate nucleus
- LP
lateral posterior complex
- LRN
lateral reticular nucleus
- MGN
medial geniculate nucleus
- MLF
medial longitudinal fascicle
- NAdg
dorsal group of nucleus ambiguus
- NPC
nucleus of the posterior commissure
- nV
trigeminal nerve
- nVII
facial nerve
- OC
optic chiasm
- OR
optic radiation
- OT
optic tract
- P
pyramidal tract
- PAG
periaqueductal grey
- PC
cerebral peduncle
- PO
posterior complex of the thalamus
- POA
preoptic area
- prV
principal trigeminal nucleus
- PTA
pretectal area
- Pu
putamen
- PUL
pulvinar nucleus
- R
red nucleus
- RF
reticular formation
- RM
nucleus raphe magnus
- RP
nucleus raphe pallidus
- RST
rubrospinal tract
- S
solitary nucleus
- SC
suprachiasmatic nucleus
- SCN
nucleus subcoeruleus
- SI
substantia innominata
- SM
stria medullaris
- SN
substantia nigra
- SO
superior olive
- SOL
solitary nucleus
- SON
supraoptic nucleus
- spV
spinal trigeminal nucleus
- spVcd
spinal trigeminal nucleus pars caudalis
- ST
stria terminalis
- TRF
retroflex tract
- VC
vestibular complex
- VTA
ventral tegmental area of Tsai
- III
oculomotor nucleus
- Vm
motor trigeminal nucleus
- VI
abducens nucleus
- VII
facial nucleus
- Xd
dorsal vagal nucleus
- XII
hypoglossal nucleus 相似文献
87.
Zhang B van Adel BA Gabriele J Duong M Henry P Ball AK Mishra RK 《Journal of chemical neuroanatomy》2002,24(1):2248-48
Catecholamine regulated protein 40 (CRP40) has been shown to be expressed in the central nervous system (CNS) of several mammalian species where it may function in a similar manner to members of the heat shock protein (HSP) family. Immunohistochemical and immunoblotting techniques were utilized to investigate whether CRP40 is expressed in normal rat retinas. In addition, changes in CRP40 expression were studied following optic nerve transection. The immunohistochemical results showed that CRP40 is expressed in the normal rat retina. The protein was found to be highly expressed in the ganglion cell layer (GCL), the inner nuclear layer (INL) and the outer plexiform layer (OPL). In addition, a low level of CRP40 was found in the inner plexiform layer (IPL), and in the inner segment layer (ISL). No expression was found in the outer nuclear layer (ONL) of normal rat retina. The immunoblotting results show that CRP40 expression decreased in a time-dependent fashion after the optic nerve transection. This decrease indicates that the expression of CRP40 is dependent on the neuron's normal physiological state and that it plays an important function in physiological and pathological conditions in the retina. 相似文献
88.
人胎儿中枢神经系统星形胶质细胞形态发育的观察 总被引:4,自引:0,他引:4
为观察人胎儿中枢神经系统星形胶质细胞形态发育。用胶质原纤维酸性蛋白抗体进行免疫组织化学染色。结果表明;1.以颈段脊髓,脑干,海马和小脑蚓部于胚胎25周其GFAP染色强度,细胞密度接近出生时水平。而此时期大脑皮层Ast密度约为出生时的四分之一。2.在同一胎龄CNS的不同部位,GFAP阳性Ast分布不均匀。3.Ast不仅在毛细胞血管周围,而且在小血管周围密度大染色深,环绕血管呈辐射状排列。 相似文献
89.
《Acta histochemica》2022,124(4):151895
Cancer is a disease characterised by abnormal cell growth that can invade or spread to other regions of the body. Organoids are three-dimensional ex vivo tissue cultures made from embryonic stem cells, induced pluripotent stem cells, progenitor cells or tissue that serve as a physiological model for cancer research. These are designed to recapitulate the in vivo properties of tumours. Importantly, effective recapitulation of the structure of tissues and function is believed to predict patient response, allowing for the creation of personalised therapy in a timely manner that may be used in the clinic. This Review discusses the pre-clinical model and different types of human organoids as models for the development of high throughput drug screening and also aims to highlight how organoids are shaping the future of cancer research. 相似文献
90.
Central amygdaloid nucleus lesions in rats had no effect on recovery of preoperative body weight and food consumption levels. The brain damaged rats also recovered preoperative levels of water consumption as rapidly as control rats but then developed a mild but persistent hypodipsia. The experimental rats also drank less than control rats when food deprived and showed marginally reliable decreases in 0.1% quinine solution consumption and latency to consume a novel food. There was no detectable lesion effect on 0.1% saccharin solution consumption, exploration of a novel environment or formation of a learned taste aversion. It is suggested that the central amygdaloid nucleus has a role in mediating the relationship between food and water intake and in some taste mediated consummatory behavior. 相似文献