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41.
Tae Kim Kristy S Hendrich Kazuto Masamoto Seong-Gi Kim 《Journal of cerebral blood flow and metabolism》2007,27(6):1235-1247
Quantifying both arterial cerebral blood volume (CBV(a)) changes and total cerebral blood volume (CBV(t)) changes during neural activation can provide critical information about vascular control mechanisms, and help to identify the origins of neurovascular responses in conventional blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI). Cerebral blood flow (CBF), CBV(a), and CBV(t) were quantified by MRI at 9.4 T in isoflurane-anesthetized rats during 15-s duration forepaw stimulation. Cerebral blood flow and CBV(a) were simultaneously determined by modulation of tissue and vessel signals using arterial spin labeling, while CBV(t) was measured with a susceptibility-based contrast agent. Baseline versus stimulation values in a region centered over the somatosensory cortex were: CBF=150+/-18 versus 182+/-20 mL/100 g/min, CBV(a)=0.83+/-0.21 versus 1.17+/-0.30 mL/100 g, CBV(t)=3.10+/-0.55 versus 3.41+/-0.61 mL/100 g, and CBV(a)/CBV(t)=0.27+/-0.05 versus 0.34+/-0.06 (n=7, mean+/-s.d.). Neural activity-induced absolute changes in CBV(a) and CBV(t) are statistically equivalent and independent of the spatial extent of regional analysis. Under our conditions, increased CBV(t) during neural activation originates mainly from arterial rather than venous blood volume changes, and therefore a critical implication is that venous blood volume changes may be negligible in BOLD fMRI. 相似文献
42.
Benjamin H. S. Lau Sharon K. Riesen Kim P. Truong Esther W. Lau Peter Rohdewald Ray A. Barreta 《The Journal of asthma》2004,41(8):825-832
A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C4/D4/E4 was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma. 相似文献
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44.
Hyun Jik Kim Jinna Kim Joo-Heon Yoon 《European archives of oto-rhino-laryngology》2006,263(8):778-782
Olfactory neuroblastoma is a rare, malignant neoplasm arising from the olfactory epithelium. It has an aggressive biological behavior that is characterized by local recurrence, atypical distant metastasis, and poor long-term prognosis. The incidence of cervical lymph node metastasis in olfactory neuroblastoma is variable, and treatment modalities are controversial. Moreover, few reports have been published concerning retropharyngeal lymph node metastasis from olfactory neuroblastoma. We present two cases of olfactory neuroblastoma with retropharyngeal lymph node metastasis. In addition, we provided a review of the current literature regarding olfactory neuroblastoma and retropharyngeal lymph node metastasis from olfactory neuroblastoma. 相似文献
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46.
Y Kim E Goldstein W Lippert T Brofeldt R Donovan 《Burns : journal of the International Society for Burn Injuries》1989,15(2):93-97
Chemotaxis, chemokinesis and cellular orientation were measured for unstimulated and 10(-7) n-formyl methionyl leucyl phenylalanine (F-met-leu-phe) stimulated polymorphonuclear leucocytes (PMNS) of nine patients with recent 10-80 per cent burns using a computer-assisted image analysis technique. The technique records PMN movement, as viewed with a phase-contrast microscope on videotapes, and then uses computer programs to calculate the speed and direction of up to 50 PMNS over a 5-min period. Orientation was determined visually. Cellular adherence was also measured by attachment methods. PMNS from burn patients were slower (av. speed 16.8 microns/min), responded less well to F-met-leu-phe (av. speed 20.9 microns/min, av. McCutcheon index 0.32), were less often oriented towards the chemoattractant (av. 39 per cent) and were more adherent (av. 50 per cent) than control cells (av. speed 21.8 microns/min; av. speed F-met-leu-phe 32.2 microns/min; McCutcheon index 0.61; oriented 59 per cent adherent; 16 per cent). Thus PMNS from burn patients orient less well, are significantly slower and have less directionality in response to a chemoattractant, and are more adherent suggesting activation. 相似文献
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48.
Miriam Stewart Linda Reutter Edward Makwarimba Irving Rootman Deanna Williamson Kim Raine Doug Wilson Janet Fast Rhonda Love Sharon McFall Deana Shorten Nicole Letourneau Karen Hayward Jeff Masuda William Rutakumwa 《Revue canadienne de recherche en sciences infirmières》2005,37(3):104-131
Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies. 相似文献
49.
This study examined the effects of cognitive-behavioral group therapy (CBT) on the self-esteem, depression, and self-efficacy of runaway adolescents residing in a shelter in Seoul, South Korea. The study used a control group pretest-posttest design. The experimental group and the control group consisted of 14 and 13 male subjects, respectively, with subjects having been randomly assigned to these groups. The experimental group participated in a CBT that consisted of eight sessions over an 8-week period; the control group did not participate in the program. To examine the effects of the CBT on dependent variables, the Wilcoxon signed rank test was used. The scores on depression decreased significantly (z = -2.325, p = .02) and those on self-efficacy increased significantly (z = -2.098, p = .03) after the intervention in the experimental group. There was no significant change on self-esteem (z = -1.19, p = .23). In the control group, the scores on depression, self-esteem, and self-efficacy did not change significantly after the intervention period. The CBT developed in this study consisted of structured and specific content that could be usefully applied to runaway adolescents residing in a shelter. 相似文献
50.