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51.
Numerous models have been developed to address key elements in the biology of breast cancer development and progression. No model is ideal, but the most useful are those that reflect the natural history and histopathology of human disease, and allow for basic investigations into underlying cellular and molecular mechanisms. We describe two types of models: those that are directed toward early events in breast cancer development (hyperplastic alveolar nodules [HAN] murine model, MCF10AT human xenograft model); and those that seek to reflect the spectrum of metastatic disease (murine sister cell lines 67, 168, 4T07, 4T1). Collectively, these models provide cell lines that represent all of the sequential stages of progression in breast disease, which can be modified to test the effect of genetic changes. 相似文献
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De Doncker S Hutse V Abdellati S Rijal S Singh Karki BM Decuypere S Jacquet D Le Ray D Boelaert M Koirala S Dujardin JC 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2005,99(1):25-31
The PCR-ELISA represents a promising advance for diagnosis of visceral leishmaniasis (VL) in blood samples. However, the method has been validated mostly with HIV-positive patients who are known to have high levels of parasitaemia. We developed a new PCR-ELISA assay for specific detection of Leishmania in patients' blood and validated it in Nepalese subjects with clinically suspected VL, almost all of whom were HIV-negative. For blood samples, PCR-ELISA was more sensitive (83.9%) than conventional PCR (73.2%), and demonstrated 100% and 87.2% specificity when using healthy controls who had never travelled to a VL-endemic area and controls from a VL-endemic area as references, respectively. We have demonstrated the ability of PCR-ELISA to detect parasites in blood of HIV-negative patients. The method could be used for epidemiological as well as clinical purposes, as it reduces the need for traumatic bone marrow sampling and risky spleen aspiration. 相似文献
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Cadmium Level in Blood and Milk from Animals Reared Around Different Polluting Sources in India 总被引:1,自引:0,他引:1
Patra RC Swarup D Naresh R Kumar P Shekhar P Ranjan R 《Bulletin of environmental contamination and toxicology》2005,74(6):1092-1097
No abstract available. 相似文献
55.
Anshuman?DarbariEmail author Abhishek?Suryavanshi Shekhar?Tandon Girish?Chandra Prashant?Kumar?Singh 《Indian Journal of Thoracic and Cardiovascular Surgery》2005,21(4):272-276
Background Non malignant tracheo-esophageal fistula is a rare entity, which is usually post traumatic, post inflammatory or could be
a delayed presentation of congenital tracheo-esophageal fistula.
Patients and Methods In this retrospective study of seven cases, we aim to document and evaluate the causes, presentation and treatment modalities.
Results All the cases underwent surgical intervention, with single stage definitive repair in four cases and two stage repair in three
cases. There was no mortality, and minimal morbidity.
Conclusions Being a benign disease with fatal complications, early diagnosis and early surgical intervention is the key to successful
management of non-malignant tracheo-esophageal fistula. 相似文献
56.
Serotonergic systems associated with arousal and vigilance behaviors following administration of anxiogenic drugs 总被引:3,自引:0,他引:3
Abrams JK Johnson PL Hay-Schmidt A Mikkelsen JD Shekhar A Lowry CA 《Neuroscience》2005,133(4):983-997
Serotonergic systems play important roles in modulating behavioral arousal, including behavioral arousal and vigilance associated with anxiety states. To further our understanding of the neural systems associated with increases in anxiety states, we investigated the effects of multiple anxiogenic drugs on topographically organized subpopulations of serotonergic neurons using double immunohistochemical staining for c-Fos and tryptophan hydroxylase combined with topographical analysis of the rat dorsal raphe nucleus (DR). Anxiogenic drugs with diverse pharmacological properties including the adenosine receptor antagonist caffeine, the serotonin 5-HT2A/2C receptor agonist m-chlorophenyl piperazine (mCPP), the alpha2-adrenoreceptor antagonist yohimbine, and the benzodiazepine receptor partial inverse agonist N-methyl-beta-carboline-3-carboxamide (FG-7142) induced increases in behavioral arousal and vigilance behaviors consistent with an increase in anxiety state. In addition, these anxiogenic drugs, excluding yohimbine, had convergent actions on an anatomically-defined subset of serotonergic neurons within the middle and caudal, dorsal subdivision of the DR. High resolution topographical analysis revealed that at the mid-rostrocaudal level, caffeine and FG-7142 had convergent effects on c-Fos expression in serotonergic neurons that were restricted to a previously undefined region, which we have named the shell region of the dorsal part of the dorsal raphe nucleus (DRDSh), that overlaps the anatomical border between the dorsal part of the dorsal raphe nucleus, the ventral part of the dorsal raphe nucleus (DRV), and the ventrolateral part of the dorsal raphe nucleus (DRVL). Retrograde tracing methods revealed that DRDSh contains large numbers of neurons projecting to the basolateral amygdaloid nucleus, a forebrain structure important for emotional appraisal and modulation of anxiety-related physiological and behavioral responses. Together these findings support the hypothesis that there is a functional topographical organization in the DR and are consistent with the hypothesis that anxiogenic drugs have selective actions on a subpopulation of serotonergic neurons projecting to a distributed central autonomic and emotional motor control system regulating anxiety states and anxiety-related physiological and behavioral responses. 相似文献
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Patients with bipolar disorder show cognitive deficits and disorganized behavior, which may reflect a disturbance in neural synchronization. We tested whether EEG measures of auditory neural synchronization were abnormal in bipolar disorder. Nineteen symptomatic patients with bipolar disorder and 32 non-psychiatric control subjects were evaluated. Click trains (500 ms duration) presented at 20, 30, 40 and 50 Hz were used to evoke EEG synchronization. Patients with bipolar disorder showed reduced power across the frequencies of stimulation. Phase-locking across trials was also disturbed in bipolar disorder, consistent with poor phase synchronization between the stimulus and EEG. Abnormal high frequency neural synchronization may contribute to cognitive deficits in bipolar disorder. 相似文献