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排序方式: 共有790条查询结果,搜索用时 46 毫秒
1.
G Dimitriou A Greenough B Laubscher N Yamaguchi 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1256-1260
Failure of patient-triggered ventilation in very immature infants may be due to the use of inappropriate triggering systems. Two types of airflow trigger were therefore compared consecutively to an airway pressure (SLE) triggering system. Each comparison was made in 10 infants, ≤28 weeks of gestation. Comparison was made of the delivered volume, trigger performance and blood gases using each system for 1 h. Both comparisons showed that the airflow triggering systems performed better: one (Draeger Babylog 8000) had a higher sensitivity ( p < 0:01) and the other (Bird VIP airflow trigger), in which inflation was terminated by sensing a reduction in inspiratory flow, had a lower degree of asynchrony ( p < 0:01) and a tendency to deliver higher volumes. These results suggest that triggering systems sensing airflow changes may be superior to those sensing airway pressure changes in very immature infants. The use of a mechanism to synchronize the termination of inflation to the end of the patient's inspiration may offer further advantages. 相似文献
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. 相似文献
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Abu-Helu RF Dimitriou ID Kapsogeorgou EK Moutsopoulos HM Manoussakis MN 《Journal of autoimmunity》2001,17(2):141-153
Sjogren's syndrome (SS) is an exocrinopathy characterized by T cell infiltrates, salivary gland epithelial cell (SGEC) apoptosis and high Fas and FasL expression. To address the participation of T cell-derived cytokines and of Fas apoptotic pathway in SS glandular lesions, we utilized non-neoplastic SGEC lines established from SS patients and controls. Possibly attesting to their intrinsic activation, cell lines derived from SS patients displayed significantly higher constitutive Fas and FasL than controls. Surface co-expression of Fas and FasL was not associated with spontaneous fratricide apoptosis. SGEC were resistant to anti-Fas-mediated apoptosis (possibly owing to the constitutive expression of anti-apoptotic proteins cFLIP and Bcl-2), but became sensitive after protein or RNA synthesis inhibition. IFN-gamma and TNF-alpha were able to upregulate surface Fas and FasL, whereas IL-1beta downregulated surface FasL. IFN-gamma (but not several other cytokines) reduced the survival of SGEC in a dose- and time-dependent manner and induced Fas/FasL-mediated apoptosis, directly and via anoikia. Dexamethasone inhibited the upregulation of Fas and FasL by IFN-gamma and the induction of SGEC apoptosis and detachment by anti-Fas mAb or IFN-gamma. Our findings indicate the injurious role of IFN-gamma for the salivary epithelia of SS patients through the induction of Fas-mediated apoptosis and anoikia. 相似文献
8.
Julia Malamitsi John Zorzos Alexandra D. Varvarigou Spyridon Archimandritis Catherine Dassiou Demosthenes V. Skarlos Panayotis Dimitriou Michael Likourinas Adamantia Zizi Charalambos Proukakis 《European journal of nuclear medicine and molecular imaging》1995,22(1):25-31
The aim of this study was the immunolocalization of transitional cell carcinoma of the bladder with a radiolabelled murine tumour-associated monoclonal antibody and the measurement of the absolute uptake of the antibody by the tumour. Fourteen patients with transitional cell carcinoma of the bladder received 3–6 mCi (111–222 MBq) of technetium-99m labelled HMFG1 monoclonal antibody intravesically and one patient, 2 mCi (74 MBq) of iodine-131 labelled 11.4.1, which is a non-tumour-specific monoclonal antibody. Four of the 15 patients were evaluated with singlephoton emission tomography (SPET) 1 1/2 to 2 h post administration. All patients underwent transurethral resection of the bladder tumour within 12–20 h following intravesical administration of the radiolabelled antibody. The radioactivity of biopsy specimens from normal urothelium and tumour areas were counted in a gamma counter. The mean uptake of the radiolabelled antibodies from normal and tumour sites was expressed as a percentage of the administered dose per kilogram of tissue. Conventional histology and immunohistochemistry using HMFGI monoclonal antibody were performed on paraffin sections of the biopsy specimens. Although our results are preliminary, it can be concluded that: (a) bladder tumours are well imaged by SPET when using99mTc-HMFG1; (b) intravesically administered radiolabelled antibody remains on the bladder tissue and does not escape into the systemic circulation; (c) the wide range of tumour uptake values (0%–9.3% administered dose/kg) observed probably can be attributed to heterogeneity of the antigenic expression of the tumour; (d) values of99mTc-HMFGI monoclonal antibody uptake by the tumour do not justify future attempts at radioimmunotherapy. 相似文献
9.
V. Kavvadia A. Greenough G. Dimitriou Y. Itakura 《European journal of pediatrics》1998,157(4):336-339
Infants born prematurely who develop chronic lung disease (CLD) have airways obstruction and hence may have low lung volume.
The aim of this study was to test that hypothesis and ascertain whether the nature of the comparison control group influenced
the results. Sixteen infants who were oxygen dependent for more than 28 days (CLD) and eight infants without CLD had measurements
of functional residual capacity (FRC) at 14 and 28 days. The 16 CLD infants consisted of eight less than 27 weeks gestational
age (group A) and eight greater than 26 weeks gestational age (group B). The eight infants without CLD (group C) were each
matched for gestational age and gender to infants in group B. Group A compared to group C had lower FRCs both at 14 days (median
18 ml/kg vs 27 ml/kg, P<0.01) and 28 days (median 20 ml/kg vs 26 ml/kg, P<0.05), but group A differed from group C with respect to both gestational age (P<0.01) and birth weight (P<0.01). The FRC results of group B were lower than those of their matched controls (group C) only at 28 days (median 22 vs
26 ml/kg, P<0.05). Overall, the FRC results at 14 and 28 days correlated significantly with the duration of oxygen and ventilator dependence
and weakly with gestational age.
Conclusion These results support the hypothesis that FRC results are lower in infants with CLD compared to those without CLD when measured
in the neonatal period and emphasize the importance of an appropriate control group. Measurement of lung volume may facilitate
assessment of the response to therapies for CLD.
Received: 5 May 1997 / Accepted in revised form: 29 September 1997 相似文献
10.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献