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91.
Mullerian duct cyst: diagnosis with MR imaging 总被引:1,自引:0,他引:1
92.
The effect of purified human fibroblast interferon on primary and secondary colony formation by blast progenitors from the peripheral blood of patients with acute myelogenous leukemia was examined. Interferon inhibited blast progenitors and normal granulocyte/macrophage progenitors (CFU-C) in a dose-dependent manner. The magnitude of this effect on blast progenitors and CFU was similar. Interferon also inhibited secondary plating of blast progenitors (self- renewal). This effect was in marked contrast to the effect of adriamycin, which reduced primary plating efficiency of blast progenitors but did not affect self-renewal. Inhibition of blast progenitor proliferation by interferon was markedly reduced when interferon was added after 24 hr of culture and was absent when added after 72 hr. Inhibition of self-renewal was observed even when interferon was added at 72 hr. We conclude that interferon inhibits both primary proliferation and self-renewal of blast progenitors and that this effect is not due to reduction in the number of primary colonies. These experiments provide an example of how cell culture techniques may be used to test antitumor agents for effects on important cellular events other than general cytotoxicity. 相似文献
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95.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
96.
Nathaniel J. Williams Jennifer L. Oberst Drey V. Campbell Lawanna Lancaster 《Community mental health journal》2011,47(3):278-285
This paper reports on two studies designed to develop and validate a treatment adherence measure for Children’s Psychosocial
Rehabilitation (CPSR)—a home- and community-based treatment for youth with serious emotional disturbance. In Study 1, we derived
CPSR treatment adherence and differentiation criteria from a treatment manual and evaluated their content validity via structured
feedback from practitioners. In study 2 we assessed the reliability and validity of the resultant CPSR Treatment Adherence
Measure (CTAM) in a clinical sample of youth receiving CPSR (n = 11) or outpatient psychotherapy (n = 20). Results from Study 1 revealed strong agreement among practitioners regarding the validity of the proposed adherence
criteria (ICC = .82). Results from Study 2 indicated the CTAM had good internal consistency (parent- and supervisor report
α’s = .86 & .91) and high inter-rater reliability (r = .87, P = .001) in this pilot sample. CTAM scores reliably distinguished between children receiving CPSR versus psychotherapy (z = −3.16, P = .002) and between CPSR interventionists with reputations for high- (n = 4) or low- (n = 7) adherence to the model (z = −2.47, P = .014). Findings indicate the CTAM is worthy of further development as a practice and research instrument. 相似文献
97.
C Oliveira RA Navarro-Xavier EA Anjos-Vallota JO Martins VLF Silveira LRC Gon?alves MS Araújo G Motta P Sannomiya MLV Oliva 《British journal of pharmacology》2010,161(4):899-910
BACKGROUND AND PURPOSE
The serine and cysteine peptidase inhibitor, BbCI, isolated from Bauhinia bauhinioides seeds, is similar to the classical plant Kunitz inhibitor, STI, but lacks disulphide bridges and methionine residues. BbCI blocks activity of the serine peptidases, elastase (Kiapp 5.3 nM) and cathepsin G (Kiapp 160.0 nM), and the cysteine peptidase cathepsin L (Kiapp 0.2 nM). These three peptidases play important roles in the inflammatory process.EXPERIMENTAL APPROACH
We measured the effects of BbCI on paw oedema and on leucocyte accumulation in pleurisy, both induced by carrageenan. Leucocyte–endothelial cell interactions in scrotal microvasculature in Wistar rats were investigated using intravital microscopy. Cytokine levels in pleural exudate and serum were measured by elisa.KEY RESULTS
Pretreatment of the animals with BbCI (2.5 mg·kg−1), 30 min before carrageenan-induced inflammation, effectively reduced paw oedema and bradykinin release, neutrophil migration into the pleural cavity. The number of rolling, adhered and migrated leucocytes at the spermatic fascia microcirculation following carrageenan injection into the scrotum were reduced by BbCI pretreatment. Furthermore, levels of the rat chemokine cytokine-induced neutrophil chemo-attractant-1 were significantly reduced in both pleural exudates and serum from animals pretreated with BbCI. Levels of interleukin-1β or tumour necrosis factor-α, however, did not change.CONCLUSIONS AND IMPLICATIONS
Taken together, our data suggest that the anti-inflammatory properties of BbCI may be useful in investigations of other pathological processes in which human neutrophil elastase, cathepsin G and cathepsin L play important roles. 相似文献98.
Background and purpose:
K+ channels play a role in the proliferation of cancer cells. We have investigated the effects of specific K+ channel inhibitors on basal and oestrogen-stimulated proliferation of breast cancer cells.Experimental approach:
Using the mammary adenocarcinoma cell line MCF-7 we assayed cell proliferation by radiolabelled thymidine incorporation in the absence or presence of various K+ channel inhibitors with or without 17β-oestradiol.Key results:
Inhibitors of Kv10.1 and KCa3.1 K+ channels suppressed basal proliferation of MCF-7 cells, but not oestrogen-stimulated proliferation. TRAM-34, a specific inhibitor of KCa3.1 channels increased or decreased cell proliferation depending on the concentration. At intermediate concentrations (3–10 µM) TRAM-34 increased cell proliferation, whereas at higher concentrations (20–100 µM) TRAM-34 decreased cell proliferation. The enhancement of cell proliferation caused by TRAM-34 was blocked by the oestrogen receptor antagonists ICI182,780 and tamoxifen. TRAM-34 also increased progesterone receptor mRNA expression, decreased oestrogen receptor-α mRNA expression and reduced the binding of radiolabelled oestrogen to MCF-7 oestrogen receptor, in each case mimicking the effects of 17β-oestradiol.Conclusions and implications:
Our results demonstrate that K+ channels Kv10.1 and KCa3.1 play a role in basal, but not oestrogen-stimulated MCF-7 cell proliferation. TRAM-34, as well as inhibiting KCa3.1, directly interacts with the oestrogen receptor and mimics the effects of 17β-oestradiol on MCF-7 cell proliferation and gene modulation. Our finding that TRAM-34 is able to activate the oestrogen receptor suggests a novel action of this supposedly specific K+ channel inhibitor and raises concerns of interpretation in its use. 相似文献99.
ME Black SS Hedgire S Camposano E Paul M Harisinghani EA Thiele 《Clinical genetics》2012,82(6):552-557
Black ME, Hedgire SS, Camposano S, Paul E, Harisinghani M, Thiele EA. Hepatic manifestations of tuberous sclerosis complex: a genotypic and phenotypic analysis. A retrospective review of the clinical records and radiological images of 205 patients with tuberous sclerosis complex (TSC) was performed to evaluate the prevalence and progression of hepatic lesions; examine the association of hepatic phenotype with genotype, age, and gender; and investigate the relationships between hepatic, renal, and pulmonary involvement. Hepatic angiomyolipomas (AML), cysts, and other benign lesions were identified in 30% of the cohort, and some lesions grew significantly over time. However, no patient had clinical symptoms or complications from hepatic lesions. TSC2 patients exhibited a higher frequency of AML compared to TSC1 patients (p = 0.037), and patients with no mutation identified exhibited a higher frequency of cysts compared to TSC2 patients (p = 0.023). Age was positively correlated with frequency of hepatic involvement (p < 0.001), whereas hepatic phenotype was independent of gender. Presence of hepatic AML was associated with presence of renal AML (p = 0.001). These findings confirm a high rate of asymptomatic hepatic lesions in TSC and further characterize the TSC phenotype. 相似文献
100.
SO Oyedemi EA Adewusi OA Aiyegoro DA Akinpelu 《Asian Pacific Journal of Tropical Biomedicine》2011,1(5):353-358