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71.
The direct reporting of adverse drug reactions by patients is becoming an increasingly important topic for discussion in the world of pharmacovigilance. At this time, few countries accept consumer reports. We present an overview of experiences with consumer reporting in various countries of the world. The potential contribution of patient reports of adverse drug reactions is discussed, both in terms of their qualitative and quantitative contribution. The crucial question is one of whether patient reports will increase the number and quality of the reports submitted and/or lead to a more timely detection of signals of possible adverse reactions, thus contributing to an enhancement of the existing methods of drug safety monitoring. To date, the data available are insufficient to establish such added value. 相似文献
72.
Missense mutation in exon 7 of the common gamma chain gene causes a moderate form of X-linked combined immunodeficiency. 总被引:6,自引:2,他引:4
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F C Schmalstieg W J Leonard M Noguchi M Berg H E Rudloff R M Denney S K Dave E G Brooks A S Goldman 《The Journal of clinical investigation》1995,95(3):1169-1173
Clinical and immunologic features of a recently recognized X-linked combined immunodeficiency disease (XCID) suggested that XCID and X-linked severe combined immunodeficiency (XSCID) might arise from different genetic defects. The recent discovery of mutations in the common gamma chain (gamma c) gene, a constituent of several cytokine receptors, in XSCID provided an opportunity to test directly whether a previously unrecognized mutation in this same gene was responsible for XCID. The status of X chromosome inactivation in blood leukocytes from obligate carriers of XCID was determined from the polymorphic, short tandem repeats (CAG), in the androgen receptor gene, which also contains a methylation-sensitive HpaII site. As in XSCID, X-chromosome inactivation in obligate carriers of XCID was nonrandom in T and B lymphocytes. In addition, X chromosome inactivation in PMNs was variable. Findings from this analysis prompted sequencing of the gamma c gene in this pedigree. A missense mutation in the region coding for the cytoplasmic portion of the gamma c gene was found in three affected males but not in a normal brother. Therefore, this point mutation in the gamma c gene leads to a less severe degree of deficiency in cellular and humoral immunity than that seen in XSCID. 相似文献
73.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
74.
M C Zillikens J W van den Berg J H Wilson G R Swart 《The American journal of clinical nutrition》1992,55(3):621-625
Bioelectrical impedance analysis (BIA) is a simple technique for determining body water and calculating body composition. It has been validated in healthy control subjects but not in patients with liver disease. We examined the ability of BIA to detect changes in total body water (TBW) due to removal of ascites. In 12 cirrhotic patients, BIA of the whole body and of body segments was performed before and after treatment of ascites with paracentesis (n = 12) and diuretics (n = 2). TBW changes predicted by BIA, by using two prediction equations, were significantly less than body weight changes (51% and 45% of the weight loss). BIA of body segments showed highly significant changes in both the trunk and the leg and small changes in the arm. These data indicate that BIA of the whole body is not a suitable technique for monitoring fluid changes in cirrhotic patients with ascites. Changes in BIA of body segments may be due to mobilization of edema after the removal of ascites. 相似文献
75.
Ingalill R. Hallberg Agneta Berg Lany T. Arlehamn 《Perspectives in psychiatric care》1994,30(2):26-32
The authors analyze a male nurse's account of how he experienced his interaction with a female schizophrenic client during sessions of systematic clinical supervision. Notes taken during 15 sessions were analyzed by means of open coding. The analysis revealed the importance of being aware of the parallel process that occurs among the client, the primary nurse, and the unit staff. 相似文献
76.
Dual activity maps in primate visual cortex produced by different temporal patterns of zif268 mRNA and protein expression
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Avi Chaudhuri Jonathan Nissanov Sylvie Larocque Lise Rioux 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(6):2671-2675
The inducible nature of the immediate-early genes (IEGs) c-fos and zif268 allows their products to be used as activity markers in the brain. The utility of such markers in general is restricted because they can resolve only neurons activated by a single stimulus. To overcome this limitation, we have developed a double-label technique that exploits the dissimilar time course of zif268 mRNA and protein induction, allowing them to be separately induced by two different stimuli and independently stained to provide a visual display of neurons that are responsive to each stimulus. Two powerful features of this new imaging technique—the possibility of staining separate populations of activated neurons and the ability to visualize them at the cellular level—should extend IEG applications in biological activity mapping. 相似文献
77.
R Pieters D R Huismans A H Loonen G J Peters K H?hlen A van der Does-van den Berg E R van Wering A J Veerman 《Leukemia research》1992,16(9):873-880
Ecto-5'-nucleotidase (ecto-5'NT) catalyzes the extracellular dephosphorylation of nucleotides like IMP. Cytoplasmic 5'NT (cyto-5'NT) and non-specific (e.g. acid- and alkaline) phosphatases (AP) regulate the intracellular degradation of nucleotides. High NT and AP activities might cause a resistance to the thiopurines 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG). We studied the relation between these enzymes and immunophenotype, drug resistance and prognosis in 77 children with acute lymphoblastic leukemia (ALL). Enzyme activities were assessed radiochemically; in vitro drug resistance was measured with the MTT assay. AP activities were higher in T-ALL and B-ALL than in precursor B-ALL. Cyto-5'NT activity was very low in all phenotypes and accounted for a significant proportion of total IMPase activity only in the very immature CD10- c mu- precursor B-ALL. CD10+ ALL cases with high ecto-5'NT activities showed a trend (p = 0.065) for a lower probability of continuous complete remission than those with a low activity. Ecto-5'NT activity was not related to in vitro drug resistance to 6-TG. A weak correlation was found between in vitro 6-TG resistance and cyto-5'NT and AP activities. We conclude that high ecto-5'NT activities do not cause a resistance to 6-thiopurines in childhood ALL. Some patients have high cyto-5'NT and AP activities associated with 6-thiopurine resistance. 相似文献
78.
Copper uptake from copper-dihistidine complexes by microvillar vesicles from human placenta was studied. Uptake occurred in two phases: a rapid initial binding followed by approximately linear uptake to equilibrium at approximately 5 min. The uptake showed temperature dependence, was saturable (apparent Vmax 10.5 +/- 1.6 nmol/(mg protein.4 min), apparent Km of 0.6 +/- 0.12 mumol/L) and decreased with increasing osmotic pressure, showing that the Cu uptake arose from accumulation within the vesicles and not from extravesicular binding or isotope exchange. Ceruloplasmin blocked uptake of 64Cu from 64Cu-dihistidine by the vesicles, with 50% inhibition achieved at a protein concentration of 5-10 mumol/L and a 64Cu-dihistidine concentration of 1.5 mumol/L. The effect was specific, because glucose oxidase, a noncopper protein, increased apparent uptake by binding copper and in turn being bound to the nitrocellulose membranes used to separate vesicles from incubation medium. Adding increasing concentrations of histidine also decreased uptake. The data presented indicate that the placenta can accumulate copper from copper-dihistidine, that ceruloplasmin can interfere with uptake and that this system will be very valuable in elucidating the first stage in transfer of copper across the placenta. 相似文献
79.
Background : The results of management of seminoma of the testis at the Department of Radiation Oncology St Vincent's Hospital, Sydney were evaluated retrospectively to: (i) establish that outcomes were in keeping with published results from centres in Australia and overseas; (ii) assess the impact of chemotherapy on management; and (iii) to determine ‘best practice’ management protocols based on our results and a review of the relevant literature. Methods : (i) Assessment of treatment results for stage I and II seminoma of the testis treated by post-orchidectomy radiotherapy and/or chemotherapy at St Vincent's Hospital between 1979 and 1993; (ii) literature review of published data from Australian and overseas centres on the management of seminoma of the testis, and in particular the use of surveillance or chemotherapy either alone, at time of relapse or combined with radiotherapy; and (iii) development of recommendations for use as management protocols in our department. Results : Our data and a review of the literature suggest that post-orchidectomy radiotherapy with chemotherapy for relapse in stage I and IIA disease results in long-term cure rates approaching 100%. Treatment with chemotherapy either routinely or selectively or using a surveillance policy is unlikely to show any improvement in outcome and may be less cost-effective and/or produce increased morbidity and the risk of secondary leukaemia. For stage IIB disease (5–10 cm) the use of initial combination chemotherapy with or without subsequent radiotherapy did not appear to give better outcomes than initial radical radiotherapy alone, reserving chemotherapy or further radiotherapy for relapse. For bulkier stage IIB disease (> 10cm). the use of initial chemotherapy plus consolidation radiotherapy appeared to be an appropriate treatment. Conclusions : Management protocols for seminoma of the testis at St Vincent's Hospital, Sydney Department of Radiation Oncology currently are (i) stage I, IA and IIB (5–10 cm): post-orchidectomy radiotherapy alone with chemotherapy or further radiotherapy for relapse; and (ii) stage IIB (> 10 cm) disease: initial chemotherapy post-orchidectomy followed by radiotherapy to sites of initial disease involvement. 相似文献
80.
Anti-mitochondrial antibodies (anti-M7) in sera from patients with dilated cardiomyopathy and myocarditis recognize, besides mitochondrial antigens, bacterial sarcosine dehydrogenase. The common target antigen was identified as the covalently bound FAD of mitochondrial and bacterial flavoenzymes. Thus, anti-M7-positive serum reacted on Western blots exclusively with covalently flavinylated enzymes. The antigenic specificity of anti-M7 sera was reproduced by an antiserum raised in rabbits with 6-hydroxy- D -nicotine oxidase. The heart mitochondrial membrane antigen recognized by anti-M7 serum was identified as the flavoprotein subunit of succinate dehydrogenase, the antigens in rat liver mitochondrial matrix as the flavoenzymes dimethylglycine dehydrogenase and sarcosine dehydrogenase. Anti-M7 serum contained a specific anti-flavoenzyme antibody fraction. Nanomolar concentrations of FAD and riboflavin inhibited the immune reaction on Western blots and in ELISA, and incubation with FAD-agarose depleted the anti-M7 activity of the serum. N-terminally deleted dimethylglycine dehydrogenase proteins were only immunoprecipitated by anti-M7 sera when the FAD was covalently incorporated. An affinity constant (KD) of 10?8 M was established for the anti-flavoenzyme antibodies by competitive ELISA. Of patients with cardiomyopathy and myocarditis, 36% and 25%, respectively, were anti-flavoenzyme-positive by Western blot and ELISA, but only two of 15 patients with other heart diseases and none of 50 healthy controls. 相似文献