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991.
992.
993.
Ahn HS Lee SW Yoon SJ Hann HJ Hong JM 《The Journal of international medical research》2004,32(3):317-323
This study aimed to investigate whether transurethral alprostadil could be used for the diagnosis of erectile dysfunction using colour duplex ultrasound. The ultrasonography results were compared after transurethral and intracavernous alprostadil administration in 20 patients with erectile dysfunction. There were no significant differences in the mean peak systolic velocities (PSVs) between the two routes of administration, but the mean end diastolic velocities (EDVs) showed significant differences, with patients treated with transurethral alprostadil having higher EDVs. Linear regression analysis of the PSVs reached following the two routes of administration showed a moderate relationship, but linear regression analysis of the EDVs showed no relationship. We concluded that transurethral alprostadil was an inappropriate vasoactive drug to use with colour duplex ultrasonography for the evaluation of patients with erectile dysfunction because it required a longer scan time and it was less effective and less reliable than intracavernous alprostadil at stimulating complete corporeal smooth muscle relaxation. 相似文献
994.
Increasing infectious disease deaths, the emergence of new infections, and bioterrorism have made surveillance for infectious diseases a public health concern. Medical examiners and coroners certify approximately 20% of all deaths that occur within the United States and can be a key source of information regarding infectious disease deaths. We hypothesized that a computer-assisted search tool (algorithm) could detect infectious disease deaths from a medical examiner database, thereby reducing the time and resources required to perform such surveillance manually. We developed two algorithms, applied them to a medical examiner database, and verified the cases identified against the opinion of a panel of experts. The algorithms detected deaths with infectious components with sensitivities from 67% to 94%, and predictive value positives ranging from 8% to 49%. Algorithms can be useful for surveillance in medical examiner offices that have limited resources or for conducting surveillance across medical examiner jurisdictions. 相似文献
995.
Rose KM Wood JL Knowles S Pollitt RA Whitsel EA Diez Roux AV Yoon D Heiss G 《International journal of health geographics》2004,3(1):27
Background
There is evidence of a contribution of early life socioeconomic exposures to the risk of chronic diseases in adulthood. However, extant studies investigating the impact of the neighborhood social environment on health tend to characterize only the current social environment. This in part may be due to complexities involved in obtaining and geocoding historical addresses. The Life Course Socioeconomic Status, Social Context, and Cardiovascular Disease Study collected information on childhood (1930–1950) and early adulthood (1960–1980) place of residence from 12,681 black and white middle-aged and older men and women from four U.S. communities to link participants with census-based socioeconomic indicators over the life course. 相似文献996.
We reviewed the medical records of patients with acute retinal artery obstruction (RAO) and evaluated the importance of transthoracic echocardiography (TTE) and carotid Doppler ultrasound in determining causes of cardiac and carotid artery origin in RAO. A retrospective case study conducted in the Department of Ophthalmology, Inha University Hospital, Korea comprised 26 patients presenting with acute RAO who underwent systemic evaluation, TTE and carotid Doppler ultrasound between June 1, 1997 and December 31, 2003. Among these 26 patients, abnormal cardiac findings were detected in 12 (46%) and abnormal carotid findings in 4 (15%). Furthermore, other risk factors for RAO were found in 2 (8%) and stroke broke out within 7 months after experiencing RAO in 4 (15%) of the 26 patients. In patients with acute RAO, TTE and carotid Doppler ultrasound play an important role in pinpointing the origins of retinal emboli. It is thought that TTE and carotid Doppler ultrasound may be essential examinations for determining the underlying cause, planning treatment strategies, and preventing stroke and death. 相似文献
997.
Changes of tear film and ocular surface in diabetes mellitus 总被引:4,自引:0,他引:4
This study was performed to investigate the changes of tear film and ocular surface in diabetic patients, as well as the ocular and systemic factors related to these changes. We assessed the scoring of keratoepitheliopathy, corneal sensitivity test, tear film break-up time (BUT), Schirmer test, and conjunctival impression cytology in 94 eyes of 47 patients with noninsulin-dependent diabetes mellitus and in 60 eyes of 30 normal subjects. The degree of keratoepitheliopathy was severe, and the corneal sensitivity, BUT, and tear secretion were significantly reduced in the diabetic patients. Conjunctival impression cytology showed a higher grade of conjunctival squamous metaplasia and lower goblet cell density in the diabetic patients. All parameters were related to the status of metabolic control, diabetic neuropathy, and stage of diabetic retinopathy. We think that diabetic patients with poor metabolic control, neuropathy, and advanced stage of retinopathy should be examined for tear film and ocular surface changes. 相似文献
998.
This study evaluated the effects of synthetic benzylamide compound I (2,6-dimethoxy-N-phenylbenzamide) on the ultraviolet B (UV B)-induced hyperpigmentation of the skin. UV B-induced hyperpigmentation was elicited on brownish guinea pig skin according to the method reported by Hideya et al. [Arch Dermatol Res 290 (1998) 375] with minor modifications. A lightening effect was observed following the topical application of compound I on UV-stimulated hyperpigmentation. The skin returned to its original color after treatment with compound I. Fontana-Masson staining indicated that melanin level in the hyperpigmented area was significantly decreased in the compound I-treated animals. However, the number of melanocytes were not changed in the compound I-treated groups using the S-100 stain, which is an immunohistochemical method. In vitro experiments using the cultured melanoma cells showed a 31.7% inhibition of melanin production by compound I at 100 microM. In addition, this compound had no effect on the tyrosinase enzyme function. However, it exhibited a catalyzing effect on the dopachrome transformation into 5,6-dihydroxyindole-2-carboxylic acid. Overall, the pigment-lightening effects of the compound I may due to the dopachrome tautomerase stimulation. 相似文献
999.
Kim YJ Cho YH Paek D Chung HW 《Journal of toxicology and environmental health. Part A》2004,67(23-24):1915-1922
Human exposure to benzene is derived occupationally from the petrochemical and petroleum refining industries. This study was performed to determine whether the frequencies of chromosome aberrations in workers exposed to low levels of benzene in a petroleum refining factory were elevated compared to an unexposed control group. The study population was comprised of 178 exposed workers and 36 unexposed workers. The frequencies of chromatid deletions and total chromosome aberrations in workers exposed to benzene were significantly higher compared to the unexposed control group. The frequency of total chromosome aberration was 4.20 per 500 metaphase cells in the exposed workers, whereas the frequency was 2.24 per 500 metaphase cells in the unexposed control group. The frequencies of total chromosome aberrations were significantly associated with benzene concentration after adjusting for confounding variables such as age, smoking status, and alcohol intake. The frequencies of chromosome aberrations were significantly increased in workers with low white blood cell counts (below 4000 cells/mm3) compared to those with high white blood cell counts (above 4000 cells/mm3). A reduced white blood cell count (below 4000/mm3) is suggestive of chronic exposure to benzene. In conclusion chronic benzene exposure and preclinical signs, such as reduced white blood cell counts, may be monitored by chromosome aberrations analysis. 相似文献
1000.
Griffin KJ Kirschner LS Matyakhina L Stergiopoulos S Robinson-White A Lenherr S Weinberg FD Claflin E Meoli E Cho-Chung YS Stratakis CA 《Cancer research》2004,64(24):8811-8815
Mutations of the human type Ialpha regulatory subunit (RIalpha) of cyclic AMP-dependent protein kinase (PKA; PRKAR1A) lead to altered kinase activity, primary pigmented nodular adrenocortical disease, and tumors of the thyroid and other tissues. To bypass the early embryonic lethality of Prkar1a(-/-) mice, we established transgenic mice carrying an antisense transgene for Prkar1a exon 2 (X2AS) under the control of a tetracycline-responsive promoter. Down-regulation of Prkar1a by up to 70% was achieved in transgenic mouse tissues and embryonic fibroblasts, with concomitant changes in kinase activity and increased cell proliferation, respectively. Mice developed thyroid follicular hyperplasia and adenomas, adrenocortical hyperplasia, and other features reminiscent of primary pigmented nodular adrenocortical disease, histiocytic and epithelial hyperplasias, lymphomas, and other mesenchymal tumors. These were associated with allelic losses of the mouse chromosome 11 Prkar1a locus, an increase in total type II PKA activity, and higher RIIbeta protein levels. This mouse provides a novel, useful tool for the investigation of cyclic AMP, RIalpha, and PKA functions and confirms the critical role of Prkar1a in tumorigenesis in endocrine and other tissues. 相似文献