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11.
The efficacy and tolerability of moclobemide (300–600 mg daily) and fluoxetine (20–40 mg daily) were compared in a 6-week, double-blind study of 65 inpatients and 34 outpatients suffering from major depressive episodes (DSM III-R). No statistically significant differences between the two treatment groups were noted regarding efficacy (HDRS, CGI) or safety (adverse events, laboratory examination, vital signs). Moclobemide (300–600 mg daily) and fluoxetine (20–40 mg daily) would thus appear to be comparable both in antidepressant efficacy and tolerability. Doubling the low dosage in non-responders after 3 weeks resulted in a statistically significant improvement of CGI in the moclobemide group by comparison with the fluoxetine group at study end, suggesting that 600 mg moclobemide/day can still improve the patient's condition, while 40 mg fluoxetine/day does not. Sexual dysfunction was reported in two patients taking fluoxetine.  相似文献   
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The organization of the thalamostriatal projections arising from the centromedian (CM) and parafascicular (Pf) thalamic nuclei in the squirrel monkey (Saimiri sciureus) was studied at both light and electron microscopic levels. Following selective injections of the anterograde axonal tracer Phaseolus vulgaris-leucoagglutinin (PHA-L) into the CM or Pf, patterns of terminal arborization within the striatum were compared to the biochemical heterogeneity of the striatum as revealed by immunohistochemical staining for the calcium-binding protein calbindin D-28k (CaBP), and histochemical staining for the enzymes acetylcholinesterase (AChE) and nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-diaphorase). The PHA-L-labeled axon terminals within the striatum were further analyzed at the ultrastructural level to characterize their pattern of synaptic organization. Dense and heterogeneous terminal fields occur in the "sensorimotor" territory of the striatum after CM injections, or in the "associative" striatal territory following Pf injections. In the associative territory labeled axons arborize in a diffuse manner predominantly within areas enriched with CaBP, AChE, or NADPH-diaphorase, representing the matrix compartment, and tend to avoid areas poor in these substances, corresponding to the patch/striosome compartment. In the sensorimotor territory labeled axons form bands that occupy a subregion of the NADPH-diaphorase-rich zone in the putamen. The terminal pattern of the CM-striatal projection suggests the existence of a more complex mosaic organization within the sensorimotor territory. Ultrastructural analysis of PHA-L-labeled elements within the striatum reveals that both CM and Pf projections form asymmetric synapses upon dendrites and spines of striatal cells. A total of 339 PHA-L-labeled boutons were examined after CM injections and compared to 293 boutons following Pf injections. After CM injections, 29% of PHA-L-labeled terminals form synapses on dendritic spines and 66% on dendritic shafts, whereas after Pf injections only 12% of synapses occur on dendritic spines compared to 81% on dendritic shafts. Labeled terminals forming axosomatic or axoaxonic synapses were not seen within the striatum following either CM or Pf injections. It is concluded that in the squirrel monkey: 1) Pf-striatal fibers profusely arborize within the matrix compartment of the associative territory, 2) CM-striatal fibers form bands that occupy a subregion of the NADPH-diaphorase-rich zone within the sensorimotor territory, and 3) that both Pf- and CM-striatal projections establish asymmetric synapses with dendrites and spines of medium-sized spiny cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
14.
Our objectives were to describe fetal cases of vertebral defects (VD), assess the diagnostic yield of fetal chromosomal analysis for VD and determine which investigations should be performed when evaluating fetal VD. We performed a retrospective chart review for fetuses with VD seen between 2006 and 2015. Cases were identified from CHU Sainte‐Justine's prenatal clinic visits, postmortem fetal skeletal surveys, and medical records. Cases with neural tube defects were excluded. Sixty‐six fetuses with VD were identified at a mean gestational age of 20 weeks. Forty‐seven (71.2%) had associated antenatal anomalies, most commonly genitourinary, skeletal/limb, and cardiac anomalies. Thirteen mothers (19.7%) had pregestational diabetes (95% CI [10.1%–29.3%]). Fifty‐three cases had chromosomal analysis. Three had abnormal results (5.6%): trisomy 13, trisomy 22, and 9q33.1q34.11 deletion. Thirty‐four (51.5%) pregnancies were terminated, one led to intrauterine fetal demise and 31 (46.9%) continued to term. Of 27 children who survived the neonatal period, 21 had congenital scoliosis and 3 had spondylocostal dysostosis. Seven had developmental delay. In conclusion, prenatal evaluation of fetuses with VD should include detailed morphological assessment (including fetal echocardiogram), maternal diabetes screening, and chromosomal microarray if non‐isolated. Our findings provide guidance about management and counseling after a diagnosis of fetal VD.  相似文献   
15.
The A 3243 G mutation of the mitochondrial tRNA(Leu) gene was found to segregate with maternally inherited diabetes mellitus, sensorineural deafness, hypertrophic cardiomyopathy, or renal failure in a large pedigree of 35 affected members in four generations. Presenting symptoms almost consistently involved deafness and recurrent attacks of migraine-like headaches, but the clinical course of the disease varied within and across generations. The A 3243 G mutation has been previously reported in association with the mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episode syndrome (MELAS) and with diabetes mellitus and deafness. To our knowledge, however, hypertrophic cardiomyopathy is not a common feature in people with the A 3243 G mutation and renal failure has not been hitherto reported in association with this mutation. The present observation gives additional support to the variable clinical expression of mtDNA mutations in humans.  相似文献   
16.
Both human bactericidal/permeability-increasing protein (BPI) and a recombinant amino-terminal fragment of BPI (rBPI23) have been shown to bind with high affinity to the lipid A region of lipopolysaccharide (LPS) (H. Gazzano-Santoro, J. B. Parent, L. Grinna, A. Horwitz, T. Parsons, G. Theofan, P. Elsbach, J. Weiss, and P. J. Conlon, Infect. Immun. 60:4754-4761, 1992). In the present study, lipid A preparations derived from bacterial LPS as well as synthetic lipid A's and various lipid A analogs were used to determine the structural elements required for rBPI23 binding. rBPI23 bound in vitro to a variety of synthetic and natural lipid A preparations (both mono- and diphosphoryl forms), including lipid A's prepared from Escherichia coli and Salmonella, Neisseria, and Rhizobium species. Binding does not require that the origin of negative charge be phosphate, since rBPI23 bound with high affinity to lipid A's isolated from Rhizobium species that contain carboxylate (Rhizobium trifolii) or sulfate (Rhizobium meliloti) anionic groups and lack phosphate. Lipid A acyl chains are important, since rBPI23 did not bind to four synthetic variants of the beta(1-6)-linked D-glucosamine disaccharide lipid A head group, all devoid of acyl chains. rBPI23 also bound weakly to lipid X, a monosaccharide lipid precursor of LPS corresponding to the reducing half of lipid A. Lipid IVA, a precursor identical to E. coli lipid A except that it lacks the 2' and 3' acyl chains, was the simplest structure identified in this study that rBPI23 bound with high affinity. These results demonstrate that rBPI23 has a binding specificity for the lipid A region of LPS and binding involves both electrostatic and hydrophobic components.  相似文献   
17.
A Parent 《Neuroscience letters》1979,15(2-3):159-164
Injections of horseradish peroxidase (HRP) into the habenula of squirrel monkeys labeled a multitude of neurons in the lateal hypothalamus and a lesser number of neurons in the internal pallidum (GPi). The distribution of labeled cells is heterogeneous and many HRP-marked pallidal neurons are intermingled with acetylcholinesterase (AChE)-rich cells in the internal medullary lamina. However, these AChE neurons do not appear to contribute significantly to the innervation of the habenula. These findings suggest species differences between rodents and primates in regard to the organization of the pallidohabenular system.  相似文献   
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Anterograde tract-tracing and immunohistochemical methods were used to study projections from the pedunculopontine tegmental nucleus (PPN) to midbrain dopaminergic neurons in the squirrel monkey (Saimiri sciureus). The PPN harbored numerous cholinergic and glutamatergic neurons, as well as neurons that displayed both cholinergic and glutamatergic markers. Injections of anterograde tracer into the PPN led to intense fiber labeling in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA). This pedunculonigral projection was partly bilateral. At the electron microscopic level, about 40–60% of the anterogradely labeled terminal boutons were glutamate-positive and formed asymmetric synapses with the dopaminergic neurons of the SNc–VTA complex. These data provide direct evidence for a pedunculonigral glutamatergic projection. This projection may play a crucial role in the control of the firing pattern of SNc–VTA dopaminergic neurons and could be involved in glutamate-mediated excitotoxicity that is believed to lead to SNc cell death in Parkinson's disease.  相似文献   
20.
To determine the possible role of Wallerian degeneration secondary to the grey matter neuronal loss in the pathogenesis of "leuko-araiosis", computerised tomography (CT) of the brain was studied in 98 normotensive and non diabetic subjects free of cardiac diseases: 32 with Alzheimer's disease, 36 with Parkinson's disease, eight with progressive supranuclear palsy, and 22 controls. In Alzheimer's disease, leuko-araiosis scores were greater than in control subjects. Leuko-araiosis was more prominent in anterior periventricular areas in Parkinson's disease and progressive supranuclear palsy, and in posterior periventricular areas in Alzheimer's disease. In two patients with Alzheimer's disease and leuko-araiosis, necropsy revealed diffuse white matter pallor, mild fibrillary astrocytosis, and in one patient limited hyaline thickening of small white matter vessels, without any infarction or hypertensive change. Changes were more severe in white matter close to cortical areas with a great density of neurofibrillary tangles. Leuko-araiosis was more severe or more widespread in Alzheimer's disease than in Parkinson's disease, progressive supranuclear palsy and normal ageing. Differences in the location of leuko-araiosis between the four groups might be due to differences in the location of the grey matter disorder and Wallerian degeneration rather than amyloid in Alzheimer's disease, Parkinson's disease, progressive supranuclear palsy and normal ageing. Wallerian degeneration might be another cause of leuko-araiosis in neuro-degenerative disorders beside previously reported extra-cerebral predisposing factors and amyloid angiopathy.  相似文献   
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