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排序方式: 共有4793条查询结果,搜索用时 31 毫秒
91.
T Yamasaki Y Narita H Hoshi S Aburaki H Kamei T Naito H Kawaguchi 《The Journal of antibiotics》1991,44(6):646-658
The synthesis and biological properties of 1-N-[4-(substituted)amidino and guanidino-2-hydroxybutyryl]kanamycins A and B are described. Reaction of 3,3",6'-tri-N-tert-butoxycarbonyl-amikacin with an appropriate amidinating or guanidinating reagent and subsequent deblocking gave a series of amikacin derivatives having an amidino or guanidino group on the 4"'-position. The corresponding kanamycin B analogs were also prepared by a similar procedure. Among these derivatives, 1-N-(4-formamidino- and guanidino-2-hydroxybutyryl)kanamycins A (7a and 7k) and B (11 and 14) exhibited antibacterial activity similar to the corresponding 4-amino analogs. The nephrotoxic potential of selected compounds is also briefly discussed. 相似文献
92.
Shunsuke Ohtahara M.D. Yasuko Yamatogi M.D. Yoko Ohtsuka M.D. 《Psychiatry and clinical neurosciences》1976,30(3):275-287
The long-term clinical and electroencepha-lographic follow-up studies were carried out for more than three years, up to 14 years in the longest, on 116 cases with Lennox syndrome. And the results of systematic study on changing patterns and outcome have been reported. The follow-up examination was performed also on West syndrome which is closely related with Lennox syndrome; especially the relationship between both syndromes regarding prognosis has been clarified.
- 1 According to the long-term follow-up on 116 cases with Lennox syndrome, there were 98 cases (84.5%) having mental defect. The remaining of seizure was observed in 71 cases (61.2%) and persisted as Lennox syndrome except for one case.
- 2 Generally speaking, the cases with age of onset before two years old showed unfavorable outcome.
- 3 There were 42 cases (36.2%), which were converted from West syndrome and showed markedly unfavorable prognosis in regard to intelligence as well as the remaining of seizure. (31 cases, 77.5%)
- 4 On the other hand, in 23 idiopathic cases, which showed no developmental retardation before onset of seizure, had favorable outcome, and the remaining of seizure was observed in eight cases (34.8%). However, even in such cases, it was noticed that those displaying mental defect at the follow-up attained 14 cases (60.9%). That is to say, it was clarified that persistence of even minor seizures induced mental deterioration.
- 5 The cases with favorable prognosis showed usually a typical slow spike-and-wave pattern electroencephalographically, whereas those with poor prognosis showed mostly an asymmetric or disorganized slow spike-and-wave pattern.
- 6 In many cases displaying signs of brain atrophy with pneumoencephalogram and accompanying overt neurological signs at the initial examination, prognosis is obviously poor.
- 7 From the follow-up examination on 94 cases with West syndrome for three to 15 years, there were 51 cases (54.3%) which was transformed into Lennox syndrome. Among them, those cases with the remaining of seizure at the time of follow-up were 44 (46.8%) out of 94 cases, of which 37 cases (83.8%) had remaining seizure as Lennox syndrome.
- 8 From the above results, it is emphasized that Lennox and West syndromes show close relationship with each other and that a study should be done on the interrelation between their prognosis.
93.
Narita Y Hatano K Kinoshita F Togawa T Yui N Endo K Koizumi M 《Kaku igaku. The Japanese journal of nuclear medicine》2000,37(3):227-236
PURPOSE: Strontium-89 chloride (89Sr) is a new radiopharmaceutical that provides effective pain relief for metastatic bone lesions, and is expected to be available soon in the palliative management for metastatic bone pain in Japan. Because of relatively long physical half life (50.5 days), 89Sr may affect to the radioactive draining-water system by exceeding the limits of activity concentration for radioactive drain. In this article, the influence of 89Sr use on the radioactive drainage system was simulated. METHODS: The standard tank capacity of drainage and draining frequency was determined from the results of questionnaire carried out for the nationwide medical and research institutes where radioisotope treatment are performed. On the assumption that 89Sr of 148 MBq for one therapy was used twice a week and several common radionuclides were used as the same activity as used at Chiba Cancer Center, the influence of 89Sr was estimated. The calculation was performed using the activity contamination ration into the draining-water system of each radionuclide of 0.01, which was legally determined. RESULTS: The simulation revealed that the sum of the contamination ratios of individual radionuclides exceeded a legal value of 1.0 in standard drainage with the capacity of 5 m3 and 10 m3 and draining frequency of 7 times per year. The actual contamination ratios of common radiopharmaceuticals measured at Chiba Cancer Center ranged from 1/100 to 1/1000 of the legal values. CONCLUSION: It is necessary that the legal value of activity contamination ratios into the draining-water system should be reassessed before starting 89Sr therapy. 相似文献
94.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献
95.
PURPOSE: To determine normal common carotid artery (CCA) flow volume, its relationship with age, and the predictability of cerebral blood flow (CBF) by color duplex sonography. SUBJECTS AND METHODS: Forty-five healthy subjects (18 men, 27 women, 23-86 years old) and 13 patients (3 men, 10 women, 51-88 years old) without neurological disease underwent color duplex sonography. All 13 patients also underwent xenon CT. CCA flow volume in the healthy subjects was measured to determine normal values. This volume was divided by mean brain weight to estimate CBF, which was correlated with CBF measured by xenon CT in regions of ipsilateral internal carotid arteries (ICA). RESULTS: In healthy subjects, CCA flow volume ranged from 155.0-458.8 ml/min (mean+/-SD: 267.77+/-59.91), corresponding to an estimated CBF of 12.43-32.84 ml/min/100 g brain weight (mean+/-SD: 20.63+/-4.22). No relationship was found between flow volume and age. A good correlation was found between estimated CBF and CBF measured by xenon CT in regions of both ICAs (gamma=0.713, p=0.0062 on the left; gamma=0.686, p=0.0096 on the right). CONCLUSION: By using color duplex sonography, we established a set of normal CCA flow volumes, which do not decline with age. Estimated CBF derived from flow volume can predict actual CBF. 相似文献
96.
Kimura S Sato T Takahashi T Narita T Hirano S Goto M 《Psychiatry and clinical neurosciences》2000,54(2):181-189
Although many clinical studies have been conducted to determine the etiological role and clinical implications of typus melancholicus for unipolar depression, maladaptive personality features in depressive patients have not been well described. This study explores typus melancholicus, as measured by the rigidity subscale of the Munich Personality Test, and maladaptive personality features, as measured by the Temperament and Character Inventory (TCI), in 131 remitted patients with DSM-IV major depression and 154 normal controls. The patients reported significantly higher scores on rigidity and harm avoidance and significantly lower scores on self-directedness and cooperativeness. Only 23.6% of the variance of the rigidity scale was explained by the variance of the seven TCI scales, in which only persistence was significantly correlated positively to rigidity. Cluster analysis identified four subgroups, two of which were characterized by a high rigidity score. One of these two subgroups showed no maladaptive personality features, as measured by the TCI, while the other showed high harm avoidance and low self-directedness. These results indicate that the personality of depressive patients is characterized not only by typus melancholicus but also by maladaptive personality features, that typus melancholicus is not well represented by any TCI scale, and that typus melancholicus and maladaptive personality features can coexist in some depressive patients. 相似文献
97.
Urinary cadmium and serum levels of estrogens and androgens in postmenopausal Japanese women. 总被引:1,自引:0,他引:1
Chisato Nagata Yasuko Nagao Chiken Shibuya Yoshitomo Kashiki Hiroyuki Shimizu 《Cancer epidemiology, biomarkers & prevention》2005,14(3):705-708
BACKGROUND: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. METHODS: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. RESULTS: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (> or = 3.00 microg/g creatinine) than in those with low urinary cadmium (< 2.00 microg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. CONCLUSION: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies. 相似文献
98.
Rushika M Perera Yoshitaka Narita Frank B Furnari Hui K Gan Carmel Murone Marika Ahlkvist Rodney B Luwor Antony W Burgess Elisabeth Stockert Achim A Jungbluth Lloyd J Old Webster K Cavenee Andrew M Scott Terrance G Johns 《Clinical cancer research》2005,11(17):6390-6399
Monoclonal antibody (mAb) 806 is a novel epidermal growth factor receptor (EGFR) antibody with significant antitumor activity that recognizes a mutant EGFR commonly expressed in glioma known as delta2-7 EGFR (de2-7 EGFR or EGFRvIII) and a subset of the wild-type (wt) EGFR found in cells that overexpress the receptor. We have used two human xenograft mouse models to examine the efficacy of mAb 806 in combination with mAb 528, a prototypical anti-EGFR antibody with similar specificity to cetuximab. Treatment of nude mice, bearing s.c. or i.c. tumor human xenografts expressing the wt or de2-7 EGFR, with mAbs 806 and 528 in combination resulted in additive and in some cases synergistic, antitumor activity. Interestingly, mAb 528 was also effective against xenografts expressing the ligand independent de2-7 EGFR when used as a single agent, showing that its antitumor activity is not merely mediated through inhibition of ligand binding. When used as single agents, neither mAbs 806 or 528 induced down-regulation of the de2-7 EGFR either in vitro or in vivo. In contrast, the combination of antibodies produced a rapid and dramatic decrease in the total cell surface de2-7 EGFR both in vitro and in xenografts. Consistent with this decrease in total cell surface de2-7 EGFR, we observed up-regulation of the cell cycle inhibitor p27(KIP1) and a decrease in tumor cell proliferation as measured by Ki-67 immunostaining when the antibodies were used in combination in vivo. Thus, mAb 806 can synergize with other EGFR-specific antibodies thereby providing a rationale for its translation into the clinic. 相似文献
99.
100.
Kaori Maeyama Kazumi Tomioka Hiroaki Nagase Mieko Yoshioka Yasuko Takagi Takeshi Kato Masami Mizobuchi Shinji Kitayama Satoshi Takada Masashi Nagai Nana Sakakibara Masahiro Nishiyama Mariko Taniguchi-Ikeda Ichiro Morioka Kazumoto Iijima Noriyuki Nishimura 《Journal of autism and developmental disorders》2018,48(5):1483-1491
Association of congenital cytomegalovirus (CMV) infection with autism spectral disorder (ASD) has been suggested since 1980s. Despite the observed association, its role as a risk factor for ASD remains to be defined. In the present review, we systematically evaluated the available evidence associating congenital CMV infection with ASD using PubMed, Web of Science, Cochrane Library, and Embase databases. Any studies on children with CMV infection and ASD were evaluated for eligibility and three observational studies were included in meta-analysis. Although a high prevalence of congenital CMV infection in ASD cases (OR 11.31, 95% CI 3.07–41.66) was indicated, too few events (0–2 events) in all included studies imposed serious limitations. There is urgent need for further studies to clarify this issue. 相似文献