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81.
Pregnant rats were treated daily with haloperidol (2 mg/kg) for 11 days until 1 day before birth. The levels of nerve growth factor (NGF), its receptor (NGFR) and NGFR-mRNA were measured in forebrain of 2-day old postnatal rats. Using Northern blot analysis, we observed a decrease in NGFR-mRNA. Furthermore, in binding studies, Kd and Bmax of treated rats were lower than in controls, but only in the low affinity binding sites. However NGF and its mRNA did not change after haloperidol treatment. In conclusion, our results suggest that prenatal haloperidol treatment can modify the development of forebrain cells, by changing NGFR expression. 相似文献
82.
83.
Castro MJ Morales P Martínez-Laso J Allende L Rojo-Amigo R González-Hevilla M Varela P Moreno A García-Berciano M Arnaiz-Villena A 《Human immunology》2000,61(11):1157-1163
MHC-G is a class Ib (non-classical) major histocompatibility complex (MHC) whose functional and evolutionary characteristics are still under scrutiny. The study of noncoding sequences in the MHC genes may provide important phylogenetic information. In this work we have sequenced the MHC-G exon 8, which encodes for the 3'UT region, in different species of primates. It has been shown that: (1) a previously described 14 base pair (bp) deletion polymorphism is human-specific and the HLA-G alleles may be classified according to its absence or presence; (2) another newly described 3 bp deletion/insertion polymorphism is also human-specific; and (3) another newly described 51 bp deletion polymorphism is common to Pongidae and humans, but is not found in other primates belonging to the Cercopithecinae family. A hypothesis on the evolutionary pathway of this gene is put forward in the light of these findings. 相似文献
84.
85.
1. Extracellular responses from post-ganglionic axons of pigeon and chick isolated ciliary ganglia were elicited by stimulation of the presynaptic nerve. Intracellular recordings were also obtained from newly hatched pigeon and chick ganglion cells. The fine structure of ganglia from pigeons of various ages was examined with the electron microscope.2. In ganglia from chick embryos and pigeons up to 10 days old, the extracellular response was unimodal with a long latency and could be blocked by the addition of D-tubocurarine (D-TC) or hexamethonium to the bathing solution. A bimodal extracellular response appeared in pigeons about 10 days after hatching. Only the second peak of the response could be blocked by D-TC or hexamethonium. The response recorded from 22 to 26-day-old pigeons was similar to that seen in the adult.3. The intracellular recordings from ganglion cells of 2-week-old pigeons exhibit two post-synaptic potentials elicited by presynaptic stimulation. The first post-synaptic potential appears to be due to current flow through the ganglion cell during the presynaptic action potential. The second is chemically mediated. In pigeons from 1 to 6 days old, only the second post-synaptic potential is observed.4. The presynaptic terminals in the 4-day-old birds were in the form of calyces. In pigeons 7 days old or older, boutons appeared. The boutons were presumably formed as a result of cleavage of calyciform nerve terminals. Myelin was seen first in the 7-day-old pigeon, was well developed in the 16-day-old bird, and persisted in the adults.5. In adult ganglia, the first component of the extracellular response decreased and was finally abolished after 10-12 hr of superfusion with Tyrode solution. The second component of the response increased concomitantly. The only anatomical change noted in the ganglia after soaking was the disruption and separation of the myelin lamellae from each other and from around the ganglion and presynaptic terminals.6. It is concluded that the myelin is necessary for electrical transmission in the pigeon ciliary ganglion. 相似文献
86.
Castro NH dos Santos RC Nelson R Beçak W Hane B Lindsey CJ Lubs HA Stevenson RE Schwartz CE 《American journal of medical genetics. Part A》2003,(1):49-51
This report describes a family with mental retardation in two brothers. The pedigree is consistent with either X-linked mental retardation or autosomal recessive inheritance. The clinical features consist of coarse face, prominent lower lip, large testes, and obesity. This same constellation of findings was observed in a family with X-linked mental retardation (XLMR) reported by Shashi et al. [2000: Am J Hum Genet 66:469-479]. Furthermore, haplotype analysis was consistent with localization of the Shashi XLMR syndrome in Xq26-q27. Thus, the family likely represents a second occurrence of the Shashi XLMR syndrome. 相似文献
87.
As previously reported, unilateral pyramidotomy in newborn rats results in the development of an aberrant ipsilateral corticospinal tract that originates from the intact side. In the present study, limb preference after unilateral pyramidotomy in adult and neonatal rats was examined in search of differences that might correlate with this aberrant tract. However, no significant differences were observed between the two groups. Postoperatively, adult animals preferred the limb corresponding to the intact corticospinal tract in spite of a pre- and postoperative testing bias toward the opposite limb. Similarly, the animals that sustained neonatal lesion followed by testing at maturity also preferred the limb corresponding to the normal crossed corticospinal tract. 相似文献
88.
C Iglesias-Osma L Gonzalez-Villaron J F San Miguel M D Caballero L Vazquez S de Castro 《Journal of clinical pathology》1995,48(3):223-225
AIM--To determine whether iron metabolism influences the incidence of systemic fungal infection in patients with haematological malignancies. METHODS--The study population comprised 74 patients who had undergone myeloablative chemotherapy. Systemic fungal infections were classified as confirmed (histological confirmation or characteristic septate hyphae) or possible (antibiotic resistant fever which resolved following administration of intravenous amphotericin B, together with either typical radiographic lesions or massive oropharyngeal candidiasis). Parameters of iron metabolism included serum iron concentrations, total iron binding capacity, serum transferrin, and ferritin concentrations and transferrin saturation values. RESULTS--Patients who developed a fungal infection had substantially increased transferrin saturation values and ferritin concentrations at diagnosis together with low serum transferrin and high serum iron concentrations. This profile was present in patients with a fungal infection regardless of the underlying haematological disorder. CONCLUSION--Increased transferrin saturation values and high ferritin concentrations may be additional risk factors for the development of systemic fungal infection in patients with haematological malignancies. 相似文献
89.
Differential neuronal survival in the avian ciliary ganglion after chronic acetylcholine receptor blockade 总被引:2,自引:0,他引:2
We have described in the preceding 2 papers the development of the pharmacological and contractile properties of all targets of the ciliary ganglion: the iris and ciliary body (Pilar et al., 1987), and the choroidal coat (Meriney and Pilar, 1987). In this paper, we examine the chronic effects of ACh receptor (AChR) blockade on ciliary ganglion neuron survival. Nicotinic or muscarinic AChR blockers were administered daily to developing chicken embryos during the normal neuronal death period in the ciliary ganglion. The effects of the blockers on ganglionic and neuromuscular transmission were assessed, and neuronal survival was assayed by counting both the total number of ganglion neurons and the selectively HRP-labeled ciliary neurons after the normal neuronal death period. Blockade of ganglionic transmission decreases survival in both populations of neurons. Blockade of neuromuscular muscular transmission increases survival in the ciliary population, which innervates the striated iris and ciliary body muscle. In contrast, blockade of synaptic activity has various influences on the survival of the choroid population, which innervates the smooth muscle of the choroid coat. Smooth muscle muscarinic receptor blockade with atropine does not influence survival. At higher doses (which block ganglionic transmission), atropine decreases choroid survival. Survival of the choroid population is increased by nicotinic blockade with 75 micrograms alpha bungarotoxin (alpha BTX), but decreased by 12.5 micrograms alpha BTX. Two main conclusions arise from these studies. Activation of postsynaptic AChRs in both the ganglion and the periphery are important in the regulation of neuronal survival. These effects usually occur in opposite directions: Blockade of ganglionic transmission decreases neuronal survival, while paralysis of neuromuscular transmission increases neuronal survival. This embodies the "balance" hypothesis (Cunningham, 1982) for neuronal survival, which states that motoneurons must balance afferent and target interactions during a critical period after synapses are formed in both regions. The present observations support this hypothesis. However, although both ciliary and choroid neurons have been shown to depend on the presence of the periphery for survival, target muscle paralysis via AChR blockade rescues the ciliary neurons but does not influence survival in the choroid population. Target-dependent regulation of choroid neuron survival during the normal neuronal death period is clearly different from the regulation of ciliary neuron survival. 相似文献
90.
A. de Castro R. Perez-Iglesias F. Vicandi A. Zapico A. Lopez-Salva 《Advances in Contraception》1987,3(4):319-322
A comparative randomized trial was carried out on two intrauterine contraceptive devices: the Nova-T and the MLCu375. The IUDs were used by 1116 and 1237 women respectively, over a period of 2 years. The reasons for IUD removal were analyzed after one and two years using the life-table method. Statistically significant differences were found in the rates for pregnancy, expulsion and removal for bleeding and/or pain favoring the MLCu375 IUD.
Resumen Se hizo una prueba comparativa al azar de dos dispositivos anticonceptivos intrauterinos: el Nova-T y el MLCu375. Los DIU fueron usados por 1116 y 1237 mujeres respectivamente, durante un período de 2 años. Las razones para quitar un DIU fueron analizadas después de uno y dos años de uso empleando el método de tabla de vida. Se encontraron diferencias estadísticas significativas en las tasas de embarazo, expulsión y remoción por sangrado y/o dolor, siendo favorables para el MLCu375.
Resumé Une étude comparative randomisée a été effectuée sur deux dispositifs contraceptifs intrautérins: le Nova-T et le MLCu375. Ces stérilets ont été utilisés respectivement par 1116 et 1237 femmes sur une période de deux ans. On a analysé après un an et après duex ans, par la méthode des tables de survie, les raisons pour lesquelles ces DIU avaient été abandonnés. Des différences significatives du point de vue statistique ont été constatées dans les taux de grossesse, d'expulsion et de retrait pour cause de saignement et/ou de douleurs, et ces différences étaient favorables au dispositif MLCu375.相似文献