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991.
Reserpine enhances amphetamine stereotypies without increasing amphetamine-induced changes in striatal dialysate dopamine 总被引:4,自引:0,他引:4
Indirect evidence suggests that amphetamine (AMPH) releases dopamine (DA) from an extravesicular, cytoplasmic pool. Disruption of vesicular DA storage by reserpine has been hypothesized to increase the concentration of extravesicular DA available for release by AMPH, which is consistent with the observation that reserpine does not prevent but augments the behavioral response to AMPH. In order to more directly test this hypothesis, the in vivo microdialysis technique was used to concurrently examine the behavioral and striatal dopaminergic response to AMPH (1.25 or 2.5 mg/kg) 24 h following reserpine pretreatment (2.5 mg/kg). Reserpine decreased tissue levels of DA by approximately 90% and reduced baseline dialysate DA concentrations by approximately 80%. Reserpine augmented the behavioural effects of AMPH, particularly increasing the occurrence and intensity of stereotypies. In contrast, reserpine did not alter the amount or duration of AMPH-induced DA release. This observation confirms that DA release by AMPH does not depend on vesicular stores but is inconsistent with the hypothesis that augmentation or behaviour by reserpine results from increased striatal DA release. 相似文献
992.
Controlled study of haloperidol, pimozide and placebo for the treatment of Gilles de la Tourette's syndrome 总被引:5,自引:0,他引:5
E Shapiro A K Shapiro G Fulop M Hubbard J Mandeli J Nordlie R A Phillips 《Archives of general psychiatry》1989,46(8):722-730
The results of this controlled study of the treatment of 57 patients with Gilles de la Tourette's syndrome suggested that both haloperidol and pimozide were more effective than placebo, but that haloperidol was slightly more effective than pimozide. Adverse effects occurred more frequently with haloperidol vs placebo than with pimozide vs placebo, but the frequency was not significantly different for haloperidol compared with pimozide. Clinically significant cardiac effects did not occur at a maximum dosage of 0.3 mg/kg or 20 mg/d for pimozide and 10 mg/d for haloperidol. However, the QTc interval was prolonged during pimozide treatment compared with that during haloperidol treatment, although the values for both medications were not in an abnormal range. 相似文献
993.
To date, chronic myopathy has not been reported (to our knowledge) to occur in carnitine palmityltransferase (CPT) deficiency, a disorder of muscle lipid metabolism. We describe two patients with CPT deficiency: a mother, who had a partial CPT deficiency associated with fixed proximal weakness but without rhabdomyolysis, and her son, who had a complete CPT deficiency (95% reduction in enzyme activity) and who suffered from classic attacks of exercise-induced rhabdomyolysis but had normal strength on recovery. Careful examination of family members of patients with complete CPT deficiency is suggested in order to identify clinically affected heterozygotes. 相似文献
994.
Paracoccidioidomycosis of the central nervous system presents either as meningeal or pseudotumoral lesions. Although occurring more frequently in the brain and meninges, they can occasionally involve the spinal cord. A case of paracoccidioidomycosis in the cervical spinal cord is reported in this paper. Difficulties in establishing the etiologic diagnosis, the importance of radiologic examination of the thorax, and the treatment of the patient are commented. In an extensive review of the literature on the subject, only three other cases have been found, which are also discussed. 相似文献
995.
D G Daniel K F Berman D R Weinberger 《The Journal of neuropsychiatry and clinical neurosciences》1989,1(4):377-384
A double-blind, placebo-controlled crossover study of the effects of apomorphine on regional cerebral blood flow (rCBF) during a prefrontal cortex activation task was undertaken to explore the role of dopamine on cortical function. The subjects were eight drug-free, chronically psychotic patients; six patients had schizophrenia. In each, apomorphine increased the relative prefrontal flow. The results suggest that enhanced prefrontal dopamine activity may reverse deficits in prefrontal cortex metabolism in schizophrenia. 相似文献
996.
Thirty-four epileptic patients, aged 9 to 36, were submitted to A/EEG between May 1987 and July 1988. All patients had a thorough clinical and EEG work-up including long-term conventional EEG, afternoon polygraphic sleep recording and, in some cases, full-night EEG and video monitoring. Patients were divided into 2 groups: group I included 19 patients (18 with symptomatic partial epilepsy (SPE) and 1 with idiopathic generalized epilepsy (IGE) in whom no seizure had ever been recorded in spite of EEG recordings averaging a total of 16 hrs 10 min, awake and asleep); group II included 15 subjects (6 with SPE, 5 with IGE, 3 with symptomatic GE and 1 with undetermined epilepsy) in whom one or several seizures had been recorded. A/EEG was performed in order to: 1) obtain better clinical and EEG characterization of seizures, 2) study the circadian distribution of seizures, 3) verify the efficacy of drug treatment and, 4) establish the epileptic or non-epileptic nature of some ictal events. The results of A/EEG were considered positive in 52.63% of group I patients and in 93.33% of group II patients. The authors discuss the specific advantages of A/EEG vs conventional EEG: recording of seizures with random occurrence, of seizures accompanied by falls, checking the remission of seizures. 相似文献
997.
998.
Morphometric analysis of obesity (ob/ob)- and diabetes (db/db)-associated hypothalamic neuronal degeneration in C57BL/KsJ mice 总被引:3,自引:0,他引:3
D R Garris 《Brain research》1989,501(1):162-170
The influence of the obese (ob/ob) and diabetes (db/db) genetic mutations on hypothalamic structure was investigated in C57BL/KsJ and C57BL/6J mice strains by morphometric analysis of medial basal nuclei which are recognized to possess glucoregulatory neurons. Brains were collected and prepared for histomorphometric analysis at selected times following the development of expressed obesity and diabetes (Type II, non-insulin dependent) syndromes in order to compare both the strain and genomic influences on neuronal viability in the hypothalamic ventromedial (VMH) and arcuate (ARC) nuclei of mutant and age-matched control mice. The severity of each syndrome was determined by monitoring the concomitant changes in body weight and blood glucose levels in all groups. Both (db/db) and (ob/ob) mutant C57BL/KsJ mice exhibited an increase in the number and distribution of degenerated neurons in the VMH and ARC nuclei relative to corresponding controls. The mutation-associated exacerbation of the normal age-related neuronal loss, as observed in control MBH nuclei, was temporally associated with the overt expression of the hyperglycemic component of the obese and diabetes syndromes in aging C57BL/KsJ mice. No temporal or causal relationships were noted between the enhanced rate of premature neuronal degeneration, and either body weight or blood glucose levels, in either (db/db) or (ob/ob) C57BL/6J mice relative to controls. These data suggest that the hyperglycemic condition which characterizes the (ob/ob) and (db/db) mutant C57BL/KsJ mice is causally associated with the pronounced, premature MBH neuronal degeneration in these mouse strains. Neuronal changes were not pronounced when the genetic mutations were expressed in C57BL/6J mice. The accompanying alterations in brain glucose metabolism, hormone sensitivity, bioamine content and function which are recognized to occur in these mutant C57BL/KsJ mice may be causally associated consequences of the observed changes in MBH structural integrity and neuronal competence, with the severity of the mutation-associated changes being related to genetic background of the murine strain. 相似文献
999.
A case of Bonnet syndrome associated with blindness due to bilateral eye disease and a posterior parasagittal meningioma is reported. It is assumed that visual afferent deprivation alone is not enough to produce the syndrome and that, in most instances, a 'cerebral factor' must be operative if hallucinoses are to occur. The distinction between hallucinosis and hallucinations is favored and a common neural circuit for the mediation of hallucinotic imageries in general is suggested. One should not immediately put the blame on obvious eye or visual pathways affections when facing cases of Bonnet syndrome, as they are not likely to explain the complex array of images perceived by any given patient. On the contrary, the possibility of a clinically covert intracranial disease should be always raised and intensively looked for. 相似文献
1000.