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981.
982.
OBJECTIVE: In a group of crime victims, the authors investigated overlap between acute stress disorder and posttraumatic stress disorder (PTSD) diagnoses and their relative ability to predict PTSD at 6 months. METHOD: A mixed-sex group of 157 victims of violent assault were interviewed within 1 month of the crime. At the 6-month follow-up, 87.9% were reinterviewed by telephone. RESULTS: At baseline the rate of acute stress disorder was 19.1%, the rate of PTSD was 21.0%, and the percentage agreement between them was 95.5%. The two diagnoses were equally effective predictors of PTSD 6 months later. CONCLUSIONS: The high level of overlap between acute stress disorder and PTSD calls into question whether, as presently formulated, they represent distinct diagnoses.  相似文献   
983.
CONTEXT: Alzheimer disease (AD) and Parkinson disease (PD) are associated with neuronal degeneration in major subcortical nuclei, but few studies have examined the neuronal degeneration in these nuclei concurrently. OBJECTIVE: To identify clinical and pathological correlates of neuronal loss in the nucleus basalis (NB), locus coeruleus (LC), and substantia nigra pars compacta (SN) in AD and PD. DESIGN: The study sample comprised 86 cases with pathologically confirmed AD, 19 cases with PD, and 13 healthy elderly control subjects. The number of nucleolated neurons was counted in representative sections of the NB, LC, and SN. Effect sizes (ES) were computed to determine the standardized difference in cell counts relative to healthy controls. RESULTS: Cases of AD showed the greatest neuronal loss in the LC (ES = 3.16) followed by the NB (ES = 1.10), but variable loss in the SN (ES = 0.16). Cases of PD also showed the greatest neuronal loss in the LC (ES = 6.47), followed by the SN (ES = 2.58) and the NB (ES = 0.85). Significant correlations were found between the number of neurons in the NB and LC in PD (r = 0.54, P<.05), as well as AD (r = 0.24, P<.05). The duration of illness correlated with greater neuronal loss in the LC and NB in AD, and greater neuronal loss in the SN in PD. CONCLUSIONS: For both AD and PD the greatest neuronal loss was found in the LC. In AD, neuronal loss was most severe and best correlated with the duration of illness in the LC, rather than in NB as traditionally expected. Correlations between neuronal loss in the LC and NB (but not SN) in both PD and AD suggest that the former 2 nuclei may share common pathogenetic susceptibilities. Given the prominent loss of neurons in the LC, detection and treatment of noradrenergic deficiencies warrant attention in both AD and PD.  相似文献   
984.
Gray C  Nukada H  Jackson DM  McMorran PD  Wu A  Ma F 《Brain research》2003,982(2):179-185
The nitrone-based free radical scavengers have potent neuroprotective activities in models of stroke in which oxidative stress plays a key role in its development. We examined the effects of S-PBN (sodium 4-[(tert-butylimino) methyl]benzene-3-sulfonate N-oxide), a spin trap nitrone, on reperfusion injury in rat peripheral nerves. Immediately after the onset of 4-h ischaemia in rat right hindlimb, S-PBN was administered via mini-osmotic pumps, containing 2 ml of S-PBN (1.2 M), inserted subcutaneously. S-PBN, in addition, was given by a single injection (50 mg/kg BW, i.p.). Mean plasma concentrations of S-PBN were significantly greater in S-PBN-treated rats than in controls after 24, 48 and 72 h of reperfusion. Pump and dosing solution analysis indicated that the rats received between 82 and 99% of the target S-PBN concentration. Morphology in sciatic, tibial and peroneal nerves was assessed after 4 h of ischaemia followed by 72 h and 7 days of reperfusion. After 72 h of reperfusion, saline-treated control rats showed endoneurial oedema at the thigh level and diffuse axonal degeneration of myelinated nerve fibres distally. S-PBN-treated nerves were normal or revealed less severe abnormalities in myelinated fibres after 72 h and 7 days of reperfusion, when compared with those in saline-treated control nerves. Morphometrically, the frequency of abnormal myelinated fibres at calf levels was significantly less in S-PBN-treated nerves than in controls. In conclusion, post-ischaemic administration of S-PBN exhibits substantial neuroprotective properties in ischemia/reperfusion nerve injury.  相似文献   
985.
From mid 1997 to end of 1999, there was a sexually-transmitted infectious syphilis outbreak mainly in heterosexual people in British Columbia, Canada, that was concentrated in Vancouver. The rate across the province increased from less than 0.5 to 3.4 per 100000, and the rate in Vancouver reached 12.9 per 100000. We aimed to eliminate the syphillis outbreak by treating people at risk of infection. In 2000, a targeted mass treatment programme provided azithromycin (1.8 g orally) to 4384 at-risk residents in this city. After the programme, syphilis frequency fell significantly for 6 months (p=0.016), but rose again in 2001. Results from curve fitting analyses showed that the number of cases in 2001 (177) was higher than expected (0.0001相似文献   
986.
987.
Cutaneous lymphomas are rare and, although some are a manifestation of systemic lymphoma, the majority arise primarily from the skin. These primary cutaneous lymphomas comprise both T- and B-cell subtypes and represent a wide spectrum of disorders, which at times can be difficult to diagnose and classify. Classical therapeutic strategies include topical corticosteroids, phototherapy, radiotherapy, retinoids, extracorporeal photopheresis, topical chemotherapy, systemic chemotherapy and biological response modifiers. Newer therapies include the synthetic retinoid bexarotene, the immunotoxin conjugate denileukin diftitox, interleukin-12 and monoclonal antibodies such as alemtuzumab and rituximab.  相似文献   
988.
A retrospective study using models was performed to evaluate the incremental expansion that occurred during mandibular lip bumper therapy in 44 adolescent patients. The purpose was to determine whether expansion occurs evenly between appointments or whether it attenuates with treatment time. Dental cast measurements were made for arch width and arch length. Treatment duration was broken into near-equal time segments and compared. Results showed that about 50% of the total expansion achieved occurred within about the first 100 days. Forty percent of the total amount of expansion occurred during the next 200 days, with only about 10% of the total expansion occurring after the first 300 days. It is unnecessary to have the appliance in place for longer than 300 days. The percentage of expansion that occurred at each time segment was not related to whether the patient had concomitant maxillary expansion.  相似文献   
989.
Professional obligations to curb the prevalence of cigarette smoking reflect the importance of this preventable risk factor for innumerable diseases. These include chronic obstructive pulmonary disease and oral, lung and other cancers, although the morbidity and mortality rates for cerebrovascular disease (e.g., ischemic strokes) and cardiovascular disease (e.g., ischemic myocardial infarction) tend to be greater. Various alternative nicotine sources (e.g., transdermal nicotine patches, nicotine gum, nicotine nasal sprays) have been incorporated into smoking cessation programs. This review is intended to increase professional awareness of nicotine delivery systems available in Canada, including safety considerations. The pathogenic potential of nicotine, regardless of source, and the contraindications to the use of nicotine replacement therapies are discussed. However, the systemic nicotine load in individuals undergoing replacement therapy is generally lower than during active smoking. Nicotine is only one of many thousands of constituents of tobacco smoke. Furthermore, nicotine replacement is usually delivered over the short term (a matter of weeks). Therefore, nicotine replacement is recognized as a relatively safe and effective aid to smoking cessation.  相似文献   
990.
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