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11.
12.
Using a subtractlve strategy, we have cloned an activation-relatedgene from a human B cell cDNA library. Sequence analysis revealedthat this gene was identical to H12.3, a gene belonging to anexpanding family of guanlne nucleotlde-blndlng protein ßsubunlts. The expression of H12.3 was induclble in the latephase of mltogen-stlmulated T and B cells. In T cells, IL-2and IL-4 by themselves had no direct effect on the expressionof H12.3, but they could augment the level of steady-state H12.3mRNA stimulated by phytohemagglutlnln. On the other hand, IFN-and IL-6 had no obvious effect on the expression in B cellswith or without Staphytococcus aureus Cowan l-stlmulatlon. CyclosporinA, a strong immunosuppressant, Inhibited the mltogen-stlmulatedexpression of H12.3, but rapamycin, another such agent, didnot. In synchronized Jurkat cells, the expression of H12.3 hadno cell cycle-dependent decrease in S and G2/M phase, whilecyclin E, which controls the progression of the cell cycle unlate G1 phase, did show a periodic expression pattern. The resultssuggest that H12.3 might be involved in regulation of lymphocyteactivation. 相似文献
13.
We focus on the mechanisms of regulation of phospholipase D (PLD) activity. Three agonists known to stimulate PLD activity, fMet-Leu-Phe (fMLP), phorbol 12-myristate 13-acetate (PMA) and V4+-OOH, induced a differential translocation of ADP-ribosylation factor (ARF), RhoA, and protein kinase Calpha (PKCalpha), all cofactors for PLD activation. Whereas fMLP recruited all three proteins to membranes, V4+-OOH only elicited RhoA translocation and PMA induced ARF and PKCalpha translocation. Three tyrosine kinases inhibitors, ST-638, methyl 2,5-dihydroxycinnamate, and genistein reduced fMLP-stimulated PLD activity by up to 80%. Furthermore, tyrosine kinase inhibitors reduced the fMLP-induced increase of GTPgammaS-stimulated PLD activity in membranes and recruitment of ARF, RhoA, and PKCalpha to the membrane fraction. The data suggest that a tyrosine phosphorylation event is located upstream of the translocation of ARF, RhoA, and PKCalpha in the signaling pathway leading to PLD activation by fMLP. RO 31-8220, a specific inhibitor of PKC, reduced PMA-induced PLD activity by 80% in intact HL60 granulocytes but enhanced fMLP-stimulated PLD activity by 60%. Although PMA alone had no effect on RhoA recruitment to the membrane fraction, in the presence of RO 31-8220 the levels of membrane-bound RhoA were increased. The levels of membrane-bound ARF and PKCalpha were unaffected by RO 31-8220 during PMA stimulation. In contrast, fMLP-induced recruitment of ARF and RhoA was insensitive to RO 31-8220 but PKCalpha translocation was increased. We propose that RhoA translocation may be regulated by PKC in an ATP-independent manner. Furthermore, increased fMLP-induced PKCalpha translocation in the presence of RO 31-8220 may partially account for the synergistic activation of PLD observed when both fMLP and RO 31-8220 are used together in intact HL60 cells. 相似文献
14.
Hernandez Natalie D. Francis Sherilyn Allen Morgan Bellamy Erica Sims Omar T Oh Hyejung Guillaume Dominique Parker Andrea Chandler Rasheeta 《Maternal and child health journal》2022,26(4):770-777
Maternal and Child Health Journal - Data are scarce regarding the prevalence and predictors of perinatal mood and anxiety disorders (PMADs) among Black women. The purpose of this study was to... 相似文献
15.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
16.
B M Churchill G A McLorie A E Khoury P A Merguerian A M Houle 《The Urologic clinics of North America》1990,17(2):343-360
Posterior urethral valves have a broad spectrum of clinical severity determined by the degree and reversibility of the long stepwise sequence of secondary pathology. Neonatal azotemia and severe bilateral reflux are particularly important negative prognostic factors. In the mild cases, valve ablation with or without delayed reconstruction is good therapy. In the very severe cases, our interpretation of all the clinical and experimental information now available suggests that the time interval and the level of decompression are extremely important. Achievement of consistent low caliceal pressure without stasis and infections should be achieved as soon as possible. We do not agree with the philosophy of "valve ablation and wait and see" for secondary reconstruction as applied to the severe cases. An analogous philosophy would be treating all respiratory infections as upper respiratory infections and applying aggressive appropriate therapy for pneumonia only if the patient does not respond clinically. However, all controversy aside, the management of neonatal infants with posterior urethral valves remains a difficult and challenging problem for us all. The real challenge will be to improve published management results to the point that the family faced with decisions regarding an in utero diagnosis of posterior urethral valves will have enough hope to continue the pregnancy. 相似文献
17.
Role of epidural medication through caudal route was studied in 109 patients having lumbago with or without sciatica to highlight the value of this mode of treatment which relieved symptoms in more than 70% of cases without hospitalisation and without being off work for long periods as in usual methods of conservative treatment.KEY WORDS: Epidural medication, Backache, Lumbago, Sciatica 相似文献
18.
The phosphodiesterase type IV (PDEIV) family of enzymes contributes to the metabolism of cAMP formed by the stimulation of beta-adrenergic, A2-adenosine, and H2-histamine receptors in the brain. Disturbances in cAMP-mediated signaling have been implicated in several neuropsychiatric disorders, and there is evidence that increasing cAMP levels through PDEIV inhibition improves the symptoms of these disorders. In the present study, the selective PDEIV inhibitors rolipram and Ro 20-1724, labeled with C-11, were evaluated in vivo in rats, as potential radioligands for imaging PDEIV enzymes with positron emission tomography (PET). Biodistribution experiments revealed a greater than threefold increased regional brain retention of [11C]rolipram as compared to [11C]Ro 20-1724. [nC]Rolipram uptake was higher in rat brain areas (e.g., cortical regions and olfactory system) showing higher expression of PDEIV enzymes, as determined previously using [3H]rolipram autoradiography or molecular genetic techniques. Binding of [n1C]rolipram and [11C]Ro 20-1724 was specific, since coadministration of high doses of unlabeled rolipram (10 mg/Kg, i.v.) or Ro 20-1724 (30 mg/Kg with [11C]rolipram and 10 mg/Kg with [11C]Ro 20-1724, i.v.) reduced radioactivity uptake in brain regions. Pretreatment with high doses of the PDEI selective inhibitor vinpocetine (10 mg/Kg, i.p., 15 min prior), or the noradrenaline reuptake inhibitor desipramine (10 mg/Kg, i.p., 30 min prior), or coinjection with the adenylyl cyclase activator forskolin (6.5 or 15 mg/Kg, i.v.), did not inhibit [11C]rolipram uptake in brain areas, suggesting binding selectivity for PDEIV enzymes. We conclude that [11C]rolipram, but not [11C]Ro 20-1724, is a promising radioligand for imaging the PDEIV enzymes with PET. 相似文献
19.
Novelty and Familiarity Activations in PET Studies of Memory Encoding and Retrieval 总被引:16,自引:3,他引:13
Tulving Endel; Markowitsch Hans J.; Craik Fergus I. M.; Habib Reza; Houle Sylvain 《Cerebral cortex (New York, N.Y. : 1991)》1996,6(1):71-79
Nine young right-handed men viewed colored pictures of people,scenes, and landscapes. Then, 24 hr later while undergoing PETscanning, they viewed previously studied (OLD) pictures in onetype of scan, and previously not seen (NEW) pictures in another.The OLD-NEW subtraction of PET images indicates familiarity,and the NEW-OLD indicates novelty. Familiarity activations,signalling aspects of retrieval, were observed in the left andright frontal areas, and posterior regions bilaterally. Noveltyactivations were in the right limbic regions, and bilaterallyin temporal and parietal regions, including area 37. These latteractivations were located similarly to novelty activations inprevious PET studies using visual words and auditory sentences,suggesting the existence of brain regions specializing in transmodalnovelty assessment The effects of novelty are seen both be haviorallyand in replicable patterns of cortical and subcortical activation.We propose a "novelty/encoding hypothesis": (1) novelty assessmentrepresents an early stage of long-term memory encoding; (2)elaborate, meaning-based encoding processes operate on the incoming information to the extent of its novelty, and therefore(3) the probability of long-term storage of information vanesdirectly with the novelty of the information. 相似文献
20.
Relationship between dopamine D(2) occupancy, clinical response, and side effects: a double-blind PET study of first-episode schizophrenia 总被引:25,自引:0,他引:25
Kapur S Zipursky R Jones C Remington G Houle S 《The American journal of psychiatry》2000,157(4):514-520
OBJECTIVE: Since all antipsychotics block dopamine D(2) receptors, the authors investigated how well D(2) receptor occupancy in vivo predicts clinical response, extrapyramidal side effects, and hyperprolactinemia. METHOD: In a double-blind study, 22 patients with first-episode schizophrenia were randomly assigned to 1.0 or 2. 5 mg/day of haloperidol. After 2 weeks of treatment, D(2) receptor occupancy was determined with [(11)C]raclopride and positron emission tomography, and clinical response, extrapyramidal side effects, and prolactin levels were measured. Patients who showed adequate responses continued taking their initial doses, those who did not respond had their doses increased to 5.0 mg/day, and evaluations were repeated at 4 weeks for all patients. RESULTS: The patients showed a wide range of D(2) occupancy (38%-87%). The degree of receptor occupancy predicted clinical improvement, hyperprolactinemia, and extrapyramidal side effects. The likelihood of clinical response, hyperprolactinemia, and extrapyramidal side effects increased significantly as D(2) occupancy exceeded 65%, 72%, and 78%, respectively. CONCLUSIONS: The study confirms that D(2) occupancy is an important mediator of response and side effects in antipsychotic treatment. The data are consistent with a "target and trigger" hypothesis of antipsychotic action, i.e., that the D(2) receptor specificity of antipsychotics permits them to target discrete neurons and that their antagonist properties trigger within those neurons intracellular changes that ultimately beget antipsychotic response. While limited to haloperidol, the relationship between D(2) occupancy and side effects in this study helps explain many of the observed clinical differences between typical and atypical antipsychotics. 相似文献