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71.
Taipoxin from the Australian taipan Oxyuranus s. scutellatus, was detoxified by reaction with p-bromophenacyl bromide and used for preparing antibodies in rabbits. Of its three subunits only the basic α-chain and the acidic γ-chain evoked antibody production, which may suggest that the neutral β-subunit is hidden in the complex. The antibodies did not cross-react with notexin from Notechis s. scutatus nor did taipoxin cross-react with antivenom against Bungarus multicinctus, in accordance with previous findings. Immunochemical studies show a strong interaction between α and γ, whereas α-β- and β-γ-interactions are weak. In animal experiments no protection was observed when antibodies (in excess) were injected i.v. 5 min after taipoxin. This confirms the irreversibility of the attack, perhaps enzymatic (phospholipase), on vital structures in the nerve terminal membranes and emphasizes the urgency of speedy antisera injections in cases of snake-bite in Australia. The modification with p-bromophenacyl bromide ought to be generally useful in the production of high-titre antibodies against snake venoms in a short time and with no ill effects in the antisera-producing animals. 相似文献
72.
73.
Barbara Seliger Derek Atkins Michaela Bock Ulrike Ritz Soldano Ferrone Christoph Huber Stefan St?rkel 《Clinical cancer research》2003,9(5):1721-1727
The HLA class I antigen-processing machinery (APM) plays a crucial role in the generation of peptides from endogenously synthesized proteins and in their presentation to cytotoxic T lymphocytes. The potential role of defects of APM components in immune escape mechanisms used by malignant cells has prompted us to analyze their expression in renal cell carcinoma (RCC) lesions with special emphasis on TAP because of its critical role in the loading of HLA class I antigens with peptides. Immunohistochemical staining of 51 formalin-fixed RCC lesions and autologous normal renal epithelium detected transporter associated with antigen processing (TAP)1 and tapasin deficiencies in 63 and 80% of the tumor lesions. Impaired low molecular weight protein (LMP)2 and LMP7 expression was found in 73 and 33% of the RCC lesions analyzed, respectively. In contrast to the high frequency of APM component down-regulation, HLA class I heavy chain and beta(2)-microglobulin defects were detected in only 12 and 10% of the lesions, respectively. Concomitant TAP1 and LMP2 deficiencies were found in approximately 57% of RCC lesions, whereas a coordinated down-regulation of all APM components occurred only in 5% of the tumor specimens analyzed. The presence of APM defects was independent of tumor stage and grade but varied significantly among the RCC subtypes. TAP abnormalities do not appear to be attributable to structural alterations because no mutations in TAP1 were detected in TAP1-deficient RCC lesions. These data suggest that TAP defects in RCC lesions are caused by regulatory abnormalities. Therefore, T-cell-based immunotherapy may benefit from the administration of cytokines that up-regulate TAP expression. 相似文献
74.
H. J. Schmitt F. Zepp S. Müschenborn G. Sümenicht A. Schuind K. Beutel M. Knuf H. L. Bock H. Bogaerts R. Clemens 《European journal of pediatrics》1998,157(3):208-214
With an increasing number of new vaccines available for routine childhood immunization, combination vaccines are needed in
order to maintain or achieve a high compliance with recommended immunization programmes. In a prospective, randomized, comparative,
multi-centre study, 822 healthy infants were enrolled to receive three doses of either a candidate or a commercially available
Haemophilus influenzae type b (Hib) vaccine concomitantly with diphtheria-, tetanus- acellular pertussis (DTaP) vaccine. Study subjects were randomly
allocated to one of the following groups: (1) separate, or (2) mixed injection of DTaP and candidate Hib vaccine, or (3) separate
injection of DTaP and commercial Hib vaccine. One year later the first 189 study subjects received either separate or mixed
injections of the same Hib and DTaP vaccines as booster doses. Evaluation of reactogenicity was based on diary cards completed
by parents. Immunogenicity was documented by measuring IgG antibody concentrations in serum samples taken before and 4 weeks
after primary and booster vaccination. No serious adverse events occurred and most local and systemic reactions were mild
to moderate. Booster doses were more reactogenic than primary doses with all groups. Antibody concentrations against pertussis
antigens were similar to those seen with DTaP alone. All but one subject had protective antibody concentrations against diphtheria
and tetanus. Primary immune response to the Hib vaccine was significantly lower in the group receiving the mixed Hib-DTaP
vaccine, however, ≥95% of vaccinees had anti-Hib antibody concentrations ≥0.15 μg/ml and there was a marked booster response
(>100-fold) in all groups.
Conclusions Mixing DTaP and Hib vaccines for primary immunization caused a decrease in anti-Hib antibody response, although after primary
immunization as after booster doses, all subjects showed antibody concentrations considered to be protective for invasive
Hib disease. Mixing of the vaccines did not result in increased reactogenicity.
Received: 13 June 1997 / Accepted in revised form: 4 September 1997 相似文献
75.
Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications. 相似文献
76.
A simple procedure for quantification of neurite outgrowth based on stereological principles 总被引:13,自引:0,他引:13
Rønn LC Ralets I Hartz BP Bech M Berezin A Berezin V Møller A Bock E 《Journal of neuroscience methods》2000,100(1-2):25-32
The molecular mechanisms controlling formation and remodelling of neuronal extensions are of considerable interest for the understanding of neuronal development and plasticity. Determination of neurite outgrowth in cell culture is a widely used approach to investigate these phenomena. This is generally done by a time consuming tracing of individual neurites and their branches. We have used stereological principles to determine the length of neurites. The total neuritic length per cell was estimated by counting the number of intersections between neurites and test lines of an unbiased counting frame superimposed on images of cell cultures obtained by conventional computer-assisted microscopy. The absolute length, L, of neurites per cell was subsequently estimated from the number of neurite intersections, I, per cell by means of the equation L=(πd/2)I describing the relationship between the number of neurite intersections and the vertical distance, d, between the test lines used. When measuring neurite outgrowth from PC12 cells and primary hippocampal neurons, data obtained by counting neuritic intersections correlated statistically significantly with data obtained using a conventional tracing technique. However, information was acquired more efficiently using the stereological approach. Thus, using the described set-up, the stereological procedure was approximately five times less time consuming than the conventional method based on neurite tracing. The study shows that stereological estimation of neuritic length provides a precise and efficient method for the study of neurite outgrowth in cultures of primary neurons and cell lines. 相似文献
77.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
78.
Boström J Janssen G Messing-Jünger M Felsberg JU Neuen-Jacob E Engelbrecht V Lenard HG Bock WJ Reifenberger G 《Journal of neurosurgery》2000,93(2):335-341
The authors report on an 11-year-old boy in whom proptosis of the eye caused by a benign intraosseous xanthofibroma of the left orbital wall became clinically apparent at the age of 4 years. Two years later he developed bilateral papilledema, at which time computerized tomography and magnetic resonance studies revealed multiple enhancing intracranial lesions. The largest mass was located in the left middle fossa; other lesions were located at the tentorium cerebelli, in both lateral ventricles, near the superior sagittal sinus, and extracranially near the left jugular vein. The mass in the left middle fossa was resected and diagnosed as juvenile xanthogranuloma (JXG). Thirty months later, the patient again became symptomatic, exhibiting behavioral abnormalities and a decrease in mental powers. At that time, the two remaining lesions in both lateral ventricles had grown enough to cause trapping of the temporal horns and raised intracranial pressure. These lesions were successively resected and histopathologically confirmed to be JXGs. However, resection of the second intraventricular lesion was complicated by postoperative bilateral amaurosis, presumably caused by postdecompression optic neuropathy. According to a review of the literature, fewer than 20 patients with JXG involving the central nervous system have been reported. The patient described in this report is the first in whom multiple intracranial JXGs developed in the absence of cutaneous manifestations. Although JXGs are biologically benign lesions, the treatment of patients with multifocal and/or progressive intracranial manifestations is problematic. 相似文献
79.
80.
C. Uleer B. Alt-Epping E. Wight B. van Oorschot N. Bock T. Dauelsberg A. D. Rose M. Gebhardt R. Tholen K. Paradies 《Der Gyn?kologe》2018,51(12):1037-1046
In April 2018 the first German interdisciplinary S3 guideline for the diagnostics, treatment, and follow-up of patients with endometrial cancer was published. This article is a summary of Chap. 9 on “Surveillance/Recurrence/Metastases of Endometrial Cancer” and is a clinically oriented abbreviated version, which includes recommendations for investigation modalities in aftercare and treatment options in cases of recurrence. Also included are aspects of psycho-oncological support and palliative medical care from the S3 guideline. 相似文献