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41.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献
42.
Radioenhancement by cisplatin with accelerated fractionated radiotherapy in a human tumour xenograft
Joschko Marion A. Webster Lorraine K. Bishop James F. Groves Janice Yuen Kally Olver Ian N. Narayan Kailash N. Ball David L. 《Cancer chemotherapy and pharmacology》1997,40(6):534-539
The aim of the present study was to investigate whether cisplatin would enhance the radioresponse of a human tumour xenograft
when given in different schedules combined with accelerated fractionated radiation therapy. A human squamous carcinoma of
the hypopharynx, FaDu, was grown in the thigh of athymic nude mice. Tumours were exposed to twice-daily 2-Gy fractions, applied
6 h apart over 2 weeks, 5 days a week, alone or combined with cisplatin given at maximally tolerated doses in three different
schedules: (1) i.p. as a single bolus (SB) or (2) i.p. as a daily bolus at 30 min before the first daily radiation fraction
or (3) s.c. as a continuous infusion through a mini-osmotic pump over 13 days, commencing 24 h prior to the first daily radiation
fraction. The end point for the study was tumour growth delay (TGD), calculated as the difference between the delay in regrowth
to 200% of the initial tumour size in treated versus control mice. SB cisplatin plus radiation showed only an additive effect
on TGD, whereas daily-bolus and continuous-infusion cisplatin demonstrated a greater than additive effect when combined with
accelerated fractionated radiation in this human tumour model. Cisplatin appears to be especially beneficial as a radiation
enhancer when given throughout the course of radiation.
Received: 15 December 1996 / Accepted: 25 March 1997 相似文献
43.
Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells 总被引:7,自引:5,他引:7
Cell to cell communication via gap junctions is essential in the
maintenance of the homeostatic balance of multicellular organisms. Aberrant
intercellular gap junctional communication (GJIC) has been implicated in
tumor promotion, neuropathy and teratogenesis. Oxidative stress has also
been implicated in similar pathologies such as cancer. We report a
potential link between oxidative stress and GJIC. Hydrogen peroxide, a
known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells
with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible
as indicated by the complete recovery of GJIC with the removal of H2O2 via
a change of fresh media. Free radical scavengers, such as t-butyl alcohol,
propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2,
which indicated that the effects of H2O2 on GJIC was probably not a
consequence of aqueous free radical damage. The depletion of intracellular
GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of
glutathione- sufficient cells with H2O2 resulted in the
hyperphosphorylation of connexin43, which is the basic subunit of the
hexameric gap junction protein, as determined by Western blot analysis.
TPA, a well-known tumor promoter, also inhibits GJIC via
hyperphosphorylation of GJIC, which is a result of protein kinase-C
activation. However, H2O2 also induced hyperphosphorylation in
GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism
of GJIC inhibition must be different from the TPA-pathway and involves GSH.
相似文献
44.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
45.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献
46.
Timothy F Cloughesy John Kuhn H Ian Robins Lauren Abrey Patrick Wen Karen Fink Frank S Lieberman Minesh Mehta Susan Chang Alfred Yung Lisa DeAngelis David Schiff Larry Junck Morris Groves Steve Paquette John Wright Kathleen Lamborn Said M Sebti Michael Prados 《Journal of clinical oncology》2005,23(27):6647-6656
PURPOSE: To determine the maximum-tolerated dose (MTD), toxicities, and clinical effect of tipifarnib, a farnesyltransferase (FTase) inhibitor, in patients with recurrent malignant glioma taking enzyme-inducing antiepileptic drugs (EIAEDs). This study compares the pharmacokinetics and pharmacodynamics of tipifarnib at MTD in patients on and off EIAEDs. PATIENTS AND METHODS: Recurrent malignant glioma patients were treated with tipifarnib using an interpatient dose-escalation scheme. Pharmacokinetics and pharmacodynamics were assessed. RESULTS: Twenty-three assessable patients taking EIAEDs received tipifarnib in escalating doses from 300 to 700 mg bid for 21 of 28 days. The dose-limiting toxicity was rash, and the MTD was 600 mg bid. There were significant differences in pharmacokinetic parameters at 300 mg bid between patients on and not on EIAEDs. When patients on EIAEDs and not on EIAEDs were treated at MTD (600 and 300 mg bid, respectively), the area under the plasma concentration-time curve (AUC)(0-12 hours) was approximately two-fold lower in patients on EIAEDs. Farnesyltransferase inhibition was noted at all tipifarnib dose levels, as measured in peripheral-blood mononuclear cells (PBMC). CONCLUSION: Toxicities and pharmacokinetics differ significantly when comparing patients on or off EIAEDs. EIAEDs significantly decreased the maximum concentration, AUC(0-12 hours), and predose trough concentrations of tipifarnib. Even in the presence of EIAEDs, the levels of tipifarnib were still sufficient to potently inhibit FTase activity in patient PBMCs. The relevance of these important findings to clinical activity will be determined in ongoing studies with larger numbers of patients. 相似文献
47.
48.
49.
Carl M. Gay C. Allison Stewart Elizabeth M. Park Lixia Diao Sarah M. Groves Simon Heeke Barzin Y. Nabet Junya Fujimoto Luisa M. Solis Wei Lu Yuanxin Xi Robert J. Cardnell Qi Wang Giulia Fabbri Kasey R. Cargill Natalie I. Vokes Kavya Ramkumar Bingnan Zhang Lauren Averett Byers 《Cancer cell》2021,39(3):346-360.e7
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50.
CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献