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991.
Reducing the migration of di-2-ethylhexyl phthalate from polyvinyl chloride medical devices 总被引:2,自引:0,他引:2
Ito R Seshimo F Haishima Y Hasegawa C Isama K Yagami T Nakahashi K Yamazaki H Inoue K Yoshimura Y Saito K Tsuchiya T Nakazawa H 《International journal of pharmaceutics》2005,303(1-2):104-112
We attempted to determine the processing conditions for decreasing the migration of phthalate esters, particularly di-2-ethylhexyl phthalate (DEHP), from polyvinyl chloride (PVC) products using a drug solvent after dilution based on the package insert. PVC sheets and PVC tubing were subjected to optical irradiation (ultraviolet (UV), visible light irradiation) and heat treatment to determine whether they are deteriorated by these treatments. UV irradiation to one side of the PVC sheet decreased the levels of DEHP migration from the sheets by almost 50%, although the amount of DEHP content in PVC sheet was observed no significant change. On the other hand, the levels of DEHP migrating from the inner surface of PVC tubing UV-irradiated from the outer surface were not decreased compared with the control. Therefore, the surface structure was examined by conducting Fourier transform infrared spectroscopy (FT-IR), electron spectroscopy for chemical analysis (ESCA) and static angle of contact measurement. In FT-IR analysis, we found that the UV-irradiated PVC sheets were exhibited broadened absorption bands with time. In ESCA analysis, the chlorine content was decreased and the oxygen content was increased with time in UV-irradiated PVC sheets. Moreover, the other treated PVC sheets shows no significant change compared with the non-UV-irradiated PVC sheet. Therefore, the surface structure of the UV-irradiated PVC sheet was changed. As a result, the migration of DEHP from PVC products can be decreased with simple treatment, such as UV-irradiation. This could be a useful method to develop novel PVC products. 相似文献
992.
Shiina Y Igarashi M Yoshioka K Tanabe T Handa S 《The Tokai journal of experimental and clinical medicine》2005,30(3):141-148
Since the clinical profile and prognosis of heart failure depending on time of the study performed, regional characteristics of background population and different race, we attempted to evaluate the prognosis of symptoms and life expectancy of Japanese patients with heart failure. We evaluated the clinical profiles and prognoses of 1,015 consecutive patients with congestive heart failure (CHF) for whom hospitalization was required. A total of 1,015 consecutive CHF patients (584 males and 431 females) were enrolled in this study, however the total number of events investigated was 1,409. Of these patients, survival was confirmed in 413 patients, death was confirmed in 299 patients, and the prognoses of 303 patients remained unknown due to transfer to other hospitals or for some other reasons. The mean age on admission was 68.4 +/- 14.9 years. In both males and females, the peak age at the onset of CHF was in the seventies, and for patients in their eighties, the number of female patients with CHF was larger than that of male patients. Major underlying heart diseases consisted of ischemic heart disease (34%), valvular heart disease (22%), dilated cardiomyopathy (11%), and hypertension (10%). Most CHF patients who had dilated cardiomyopathy as an underlying disease were hospitalized several times, and 45% of them were hospitalized 3 times or more. The life expectancy of patients with CHF caused by ischemic heart disease was the poorest, and their 5-year and 10-year survival rates were 55% and 38%, respectively. Similarly, 5-year and 10-year survival rates of patients with CHF caused by valvular heart disease, hypertension, and dilated cardiomyopathy were 62% and 44%, 58% and 53%, and 70% and 65%, respectively. In 299 deceased patients, the mean age at death was 72.2 +/- 13.9 years. In all these deceased patients, direct causes of death were sudden death (16.1%), CHF (42.2%), others (31.4%), and unknown (10.4%). The frequency of sudden death was highest (25%) in patients with CHF caused by dilated cardiomyopathy, followed by those with CHF caused by valvular heart disease (18%) and those with CHF caused by ischemic heart disease (17.5%). In addition, the frequency of death from CHF was highest (60%) in those with CHF caused by dilated cardiomyopathy, followed by those with CHF caused by ischemic heart disease (49.2%). 相似文献
993.
Nishida K Fujiwara R Kodama Y Fumoto S Mukai T Nakashima M Sasaki H Nakamura J 《Pharmaceutical research》2005,22(8):1331-1337
Purpose The purpose of this study was to examine drug distribution in the liver after drug application to the rat liver surface.Methods Phenolsulfonphthalein (PSP) and fluorescein isothiocyanate dextran (MW 4400, FD-4) as model compounds or 5-fluorouracil (5-FU) was applied to the rat liver surface by employing a cylindrical diffusion cell (i.d. 9 mm, 0.64 cm2). Then, blood and the remaining solution in the diffusion cell were collected at selected times, followed by excision of the liver. The excised liver was divided into three sites: the region under the diffusion cell attachment site (site 1), the applied lobe except for site 1 (site 2), and non-applied lobes (site 3).Results In the case of i.v. administration, there were no differences in PSP concentrations among the three sites of the rat liver, and the concentrations rapidly decreased. On the other hand, the PSP concentration in site 1 after application to the rat liver surface was considerably higher than in site 2 and site 3. In addition, the area under the curve (AUC) value (AUCsite1), calculated from the PSP concentration profile in site 1, was about 10 times larger than that in site 3. A similar trend of regional delivery advantage by liver surface application was observed in the case of the macromolecule model FD-4, with a marked AUCsite1 of about 5 times larger than the other two sites. Moreover, we clarified that the anticancer drug 5-FU preferentially distributed in site 1 after application to the rat liver surface.Conclusion These results demonstrate the possibility of regional delivery of drugs to the liver by application to the liver surface. 相似文献
994.
Igarashi M Takahashi Y Shitara T Nakamura H Naganawa H Miyake T Akamatsu Y 《The Journal of antibiotics》2005,58(5):327-337
Novel antibiotics, active against acid-fast bacteria, caprazamycins, were isolated from the culture broth of Streptomyces sp. MK730-62F2. The planar structures of the compounds were determined by 2D NMR spectroscopic study. Furthermore, the absolute structure of caprazamycin B (2) was established by NMR spectroscopy and X-ray crystallography of its degradation products and by total synthesis of the 5-amino-5-deoxy-D-ribose moiety. In the course of degradation studies of 2 under alkaline and acidic conditions, we obtained the two core components, caprazene (11) and caprazol (14), respectively, in high yield. Structurally, caprazamycins belong to a family of lipouridyl antibiotics, which have been discovered as specific inhibitors of a bacterial translocase. 相似文献
995.
Microbial metabolites were screened for inhibitors of hyphal growth in Candida albicans. Inhibitory activity was found among metabolites of a culture of an actinomycete, which had been isolated from soil. The active substance inhibited hyphal growth and induced growth as a chain of yeast cells under hyphal growth induction conditions. The active substance was purified and analyzed with 1H-NMR, 13C-NMR and mass spectra. The substance was identified as valinomycin, and commercial valinomycin inhibited hyphal growth as effectively as the purified metabolite. The effective concentration was from 0.49 to 62.5 microg/ml. Valinomycin also inhibited hyphal growth in other dimorphic fungi, Candida tropicalis and Aureobasidium pullulans. These results suggest that valinomycin may be a useful tool for understanding the morphological transition of dimorphic fungi. 相似文献
996.
The structure assigned to the antitumor antibiotic BU-4664L from Micromonospora sp. was revised to 5,10-dihydro-4,6,8-trihydroxy-10-(3,7,11-trimethyl-trans-2,trans-6,10-dodecatrienyl)-11H-dibenzo[b,e] [1,4]-diazepin-11-one based on the NMR analysis. 相似文献
997.
Sakano Y Mutsuga M Tanaka R Suganuma H Inakuma T Toyoda M Goda Y Shibuya M Ebizuka Y 《Biological & pharmaceutical bulletin》2005,28(2):299-304
Ethanol extracts of lyophilized vegetables were tested for inhibition of human lanosterol synthase (hOSC) in order to find the compounds to suppress cholesterol biosynthesis. Of 130 samples tested, twelve samples showed significant inhibition. Among them, Colocasia esculenta (taro) showed the highest inhibition (55% inhibition at 300 microg/ml). Examination of activity variation among eight taro cultivars indicated that "Aichi-wase" and "Yatsugashira" had the most potent activity for hOSC inhibition. In order to identify the active constituent of taro, ethanol extracts of "Aichi-wase" were partitioned with hexane and aqueous methanol, and fractionated by silica gel column chromatography. Inhibitory activity was concentrated in two major active fractions. Further purification of these fractions by preparative HPLC gave three monogalactosyldiacylglycerols and five digalactosyldiacylglycerols as active compounds that showed 28 to 67% inhibitory activities at the concentration 300 microg/ml. 相似文献
998.
Dye Spraying and Magnifying Endoscopy for Dysplasia and Cancer Surveillance in Ulcerative Colitis 总被引:5,自引:1,他引:4
Sada M Igarashi M Yoshizawa S Kobayashi K Katsumata T Saigenji K Otani Y Okayasu I Mitomi H 《Diseases of the colon and rectum》2004,47(11):1816-1823
PURPOSE The aim of this study was to investigate detection of dysplasia or colitic cancer with ulcerative colitis by use of magnifying endoscopic observation.METHODS From 1986 through 2000, ulcerative colitis was diagnosed and treated in 886 patients at Kitasato University East Hospital. Of the total, we studied 25 patients in depth: 14 who had dysplasia alone, 5 in whom cancer was diagnosed during follow-up after the detection of dysplasia, and 6 who had colitic cancer.RESULTS Dysplasia was detected in 11 (3.2 percent) of 345 patients with extensive colitis and in 8 (3.7 percent) of 217 with left-sided colitis. Colorectal cancer was diagnosed in nine patients (2.6 percent) with extensive colitis and in two (0.9 percent) with left-sided colitis. Neither dysplasia nor colitic cancer was found in patients with proctitis-type colitis. Endoscopically, dysplasia and early cancer were characterized by granular or nodular protruding mucosa or by lowly protruding or flat mucosa, often associated with redness. Dye-spraying endoscopy was useful for detection. Magnifying endoscopy of ten regions of dysplasia (7 patients) and five early cancers (4 patients) showed IIIS to IIIL type pits or IV type pits. Biopsy of sites showing tumorous pits on magnifying endoscopy revealed dysplasia and early cancer. Observation of the pit pattern was found to be diagnostically useful.CONCLUSIONS Dye spraying and magnifying endoscopy are useful for the detection, targeted biopsy, and diagnosis of dysplasia and colitic cancer in patients with ulcerative colitis. 相似文献
999.
Kato M Igarashi H Takeda A Horie S Higashihara E Matano T 《Japanese journal of infectious diseases》2004,57(5):220-223
Virus-specific CD8+ cytotoxic T lymphocyte (CTL) responses play an important role in the control of immunodeficiency virus infections. Therapeutic immunization with antigen-pulsed dendritic cells (DC) may be a promising strategy for stimulating CTL. However, decreases in DC number and function have been suggested in the host persistently infected with the virus, and this may constitute an obstacle to DC-based immunotherapy in the chronic phase. In this study, we show that virus-specific CTL responses were augmented by therapeutic immunization with inactivated virus-pulsed autologous DC in rhesus macaques that had maintained prophylactic vaccine-based control of virus replication for more than 3 years after simian or simian-human immunodeficiency virus challenge. Our results indicate the potential of DC in the chronic phase for efficiently stimulating CTL in vivo, suggesting the feasibility of therapeutic DC immunization for replenishing virus-specific CTL responses in the chronic phase after the prophylactic vaccine-based control of primary immunodeficiency virus infection. 相似文献