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1.
2.
As a result of policy changes and developments on the demand side, the importance of technology in primary health care will grow fast. An approach to the implementation of new technologies in primary health care is presented in this article. First we describe the main problems in Dutch primary health care. The second step is to identify new technologies which are becoming available. Subsequently, the interface between these problems and their possible technological resolution has to be found. The fact that a technological innovation appears to be a solution is not sufficient reason for introducing it. There are all kinds of reasons why an innovation that has proved useful in the hospital situation, for example, might be of doubtful use in primary health care. Accordingly, the next step is to assess whether a technological solution to a problem in primary health care is indeed an improvement. To acknowledge the particular situation of primary health care, a scheme has been developed that may be used to determine criteria of evaluation. 相似文献
3.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
4.
C. M. A. Pennartz R. F. Ameerun H. J. Groenewegen F. H. Lopes da Silva 《The European journal of neuroscience》1993,5(2):107-117
Extra- and intracellular recordings in slices were used to examine what types of synaptic plasticity can be found in the core of the nucleus accumbens, and how these forms of plasticity may be modulated by dopamine. Stimulus electrodes were placed at the rostral border of the nucleus accumbens in order to excite primarily infralimbic and prelimbic afferents, as was confirmed by injections of the retrograde tracer fluoro-gold. In extracellular recordings, tetanization induced long-term potentiation (LTP) of the population spike in 20 out of 53 slices. The presynaptic compound action potential did not change following LTP induction. For the intracellularly recorded excitatory postsynaptic potential, three types of synaptic plasticity were noted: long-term potentiation (16 out of 54 cells), decremental potentiation (eight cells) and long-term depression (LTD; six cells). No correlation was found between the occurrence of potentiation or depression and various parameters of the tetanic depolarization (e.g. peak voltage, integral under the curve). The N -methyl- d -aspartate receptor antagonist d (–)-2-amino-5-phosphonopentanoic acid (50 μM; d -AP5) reduced, but did not completely prevent, the induction of LTP. The incidence of LTD was not markedly affected by d -AP5. No difference in LTP was found when comparing slices bathed in dopamine (10 μM) and controls. Likewise, slices treated with a mixture of the D1 receptor antagonist Sch 23390 (1 μM) and the D2 antagonist S (–)-sulpiride (1 μM) generated a similar amount of LTP as controls. In conclusion, both LTP and LTD can be induced in a key structure of the limbic-innervated basal ganglia. LTP in the nucleus accumbens strongly depends on N -methyl- d -aspartate receptor activity, but is not significantly affected by dopamine. 相似文献
5.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
6.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
7.
Room P. Groenewegen H. J. Lohman A. H. M. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1984,56(3):488-496
Summary The spatial organization and laminar distribution of projections from the olfactory bulb and the anterior (PPCa) and posterior (PPCp) divisions of the prepiriform cortex to the entorhinal cortex were studied with anterograde (3H-leucine) and retrograde (WGA-HRP) tracing techniques. After 3H-leucine injections into the olfactory bulb transported labeling was seen over the lateral entorhinal area, except its most medial part, and over the rostral part of the medial entorhinal area. The labeling covers exclusively layer Ia. The lateral and medial entorhinal areas are also reached by fibers from the prepiriform cortex. The projection to the medial entorhinal area has not been described previously. Following injections of 3H-leucine into the PPCa transported labeling is present over the entire expanse of the entorhinal cortex and is located over layer Ib with the greatest density in its superficial part. Injections of 3H-leucine into the PPCp give rise to transported labeling over much of the entorhinal cortex. No labeling was found over the most medial parts of the medial subdivision (VMEA) of the lateral entorhinal area and the medial entorhinal area. Labeling occupies layer Ib, especially its middle part, and layers II and III. Both PPCa and PPCp appear to project most heavily to the dorsal (DLEA) and ventral (VLEA) subdivisions of the lateral entorhinal area. From the retrograde experiments it can be inferred that cells of layers II and III of the PPCa project predominantly to the DLEA, whereas those of the PPCp project predominantly to the VLEA. The MEA receives its heaviest projection from layer II of both PPCa and PPCp. In control experiments with 3H-leucine injections into the endopiriform nucleus it was found that this nucleus projects to the entire expanse of the entorhinal cortex. The fibers distribute to all layers with the exception of layer Ia.Abbreviations AI
agranular insular cortex
- AL
lateral nucleus of the amygdala
- BL
basolateral nucleus of the amygdala
- BM
basomedial nucleus of the amygdala
- C
claustrum
- CoA
cortical nucleus of the amygdala
- DLEA
dorsal division of the lateral entorhinal cortex
- END
endopiriform nucleus
- H
hippocampus
- I
granular insular cortex
- lot
lateral olfactory tractus
- MCL
mitral cell layer of the olfactory bulb
- MEA
medial entorhinal area
- OB
olfactory bulb
- PPCa
anterior part of the prepiriform nucleus
- PPCp
posterior part of the prepiriform nucleus
- VLEA
ventral division of the lateral entorhinal cortex
- VMEA
ventromedial division of the lateral entorhinal cortex
- 35
area 35 of the perirhinal cortex
- 36
area 36 of the perirhinal cortex 相似文献
8.
van Dongen YC Deniau JM Pennartz CM Galis-de Graaf Y Voorn P Thierry AM Groenewegen HJ 《Neuroscience》2005,136(4):1049-1071
The nucleus accumbens is thought to subserve different aspects of adaptive and emotional behaviors. The anatomical substrates for such actions are multiple, parallel ventral striatopallidal output circuits originating in the nucleus accumbens shell and core subregions. Several indirect ways of interaction between the two subregions and their associated circuitry have been proposed, in particular through striato-pallido-thalamic and dopaminergic pathways. In this study, using anterograde neuroanatomical tracing with Phaseolus vulgaris-leucoagglutinin and biotinylated dextran amine as well as single-cell juxtacellular filling with neurobiotin, we investigated the intra-accumbens distribution of local axon collaterals for the identification of possible direct connections between the shell and core subregions. Our results show widespread intra-accumbens projection patterns, including reciprocal projections between specific parts of the shell and core. However, fibers originating in the core reach more distant areas of the shell, including the rostral pole (i.e. the calbindin-poor part of the shell anterior to the core) and striatal parts of the olfactory tubercle, than those arising in the shell and projecting to the core. The latter projections are more restricted to the border region between the shell and core. The density of the fiber labeling within both the shell and core was very similar. Moreover, specific intrinsic projections within shell and core were identified, including a relatively strong projection from the rostral pole to the rostral shell, reciprocal projections between the rostral and caudal shell, as well as projections within the core that have a caudal-to-rostral predominance. The results of the juxtacellular filling experiments show that medium-sized spiny projection neurons and medium-sized aspiny neurons (most likely fast-spiking) contribute to these intra-accumbens projections. While such neurons are GABAergic, the intrastriatal projection patterns indicate the existence of lateral inhibitory interactions within, as well as between, shell and core subregions of the nucleus accumbens. 相似文献
9.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
10.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献