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排序方式: 共有638条查询结果,搜索用时 46 毫秒
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C. Calatozzolo A. Salmaggi B. Pollo F.L. Sciacca M. Lorenzetti A. Franzini A. Boiardi G. Broggi C. Marras 《Neurological sciences》2007,28(6):304-310
Recent studies have shown an anti-tumour activity of cannabinoid receptors CB1 and CB2 in gliomas. This effect was mediated
by neurotrophins in breast and prostate carcinoma, while in gliomas this relationship has not yet been considered. The aim
of this study was to investigate the expression of cannabinoid receptors CB1 and CB2, neurotrophin NGF and NT-3 and their
receptors TrkA and TrkC in glioma and endothelial cells. The analysis was performed in 14 gliomas and 2 non-tumour brain specimens
by immunohistochemistry and real-time quantitative-polymerase chain reaction (RTQ-PCR). Gliomas showed a weak immunoreactivity
for CB1 and CB2 in tumour and in endothelial cells, and for NGF/TrkA mainly in tumour cells, while a moderate/diffuse immunoreactivity
was found for NT-3/TrkC. CB2 was expressed on 3 out of 6 low-grade gliomas and in all high-grade gliomas. Non-tumour brain
tissues were weakly positive in astrocytes and endothelium for CB1, CB2, NT-3 and TrkC and negative for NGF and TrkA. By RTQ-PCR,
gliomas showed low mRNA levels of NGF/TrkA and moderate levels of CB1, NT-3 and TrkC. CB2 mRNA expression was low or absent.
A potential role of cannabinoids, particularly of CB2 agonists devoid of psychotropic side effects, in glioma therapy could
have a basis in glioblastomas, because they were all positive, though weakly, to CB2. The presence of neurotrophins and their
receptors, mainly NT-3 and TrkC, suggests a possible role of these pathways in glioma growth/invasion, but further investigations
are required to verify this hypothesis and a potential relationship between cannabinoids and neurotrophins. 相似文献
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A Sgalambro A Marras F Lombardi C Guasconi G Schiavone G Sportelli S Del Giudice C Marinoni 《Giornale italiano di cardiologia》1987,17(8):667-672
Tricuspid regurgitation (TR) is detected by Doppler echocardiography in a high proportion of patients with right ventricle pressure or volume overload. Continuous wave Doppler (CW) provides a noninvasive estimation of the transtricuspid systolic pressure gradient, applying the modified Bernoulli formula to the maximum velocity of the TR jet. The purpose of this study was to test the accuracy of the CW prediction of systolic right ventricular pressure (RVPs), obtained adding a clinical estimate of the mean right atrial pressure (RAPm) to the Doppler derived pressure gradient. The study population consisted of 22 adult patients with Doppler proved TR, undergoing right heart catheterization (cath) for mitral valve disease (12 pts), atrial septal defect (8 pts), dilated cardiomyopathy (1 pt) or pulmonary hypertension (1 pt). Two studies were duplicated after nifedipine administration. TR was graded by pulsed Doppler flow mapping as mild in 7, moderate in 11, severe in 4 pts. RAPm was estimated clinically from the inspection of neck veins pulsatility (mmHg = pulsatility cm+5/1.3). At CATH RVPs ranged from 27 to 80 (46 +/- 17) mmHg, RAPm from 0 to 13 (6 +/- 3) mmHg. RVPs Doppler prediction showed a close correlation with CATH (r .97, SEE 4.2 mmHg), with a slight mean underestimation (-2 +/- 4 mmHg) (Fig. 3, Tab. I). The discrepancies between CW and CATH ranged from -9 to +10 mmHg, almost entirely due to inaccuracy of the RAPm clinical estimate (r .48, see 3.8 mmHg) (Fig. 4, Tab. I).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Development of a molecular-beacon assay to detect the G1896A precore mutation in hepatitis B virus-infected individuals 总被引:1,自引:0,他引:1
Waltz TL Marras S Rochford G Nolan J Lee E Melegari M Pollack H 《Journal of clinical microbiology》2005,43(1):254-258
The 1896 precore (PC) mutation is the most frequent cause of hepatitis B virus e-antigen (HBeAg)-negative chronic hepatitis B virus (HBV) infection. Detection of the 1896 PC mutation has application in studies monitoring antiviral therapy and the natural history of the disease. Identification of this mutation is usually performed by direct sequencing, which is both costly and laborious. The aim of this study was to develop a rapid, high-throughput assay to detect the 1896 PC mutation using real-time PCR and molecular-beacon technology. The assay was initially standardized on oligonucleotide targets and plasmids containing the wild-type (WT) and PC mutation and then tested on plasma samples from children with HBV DNA of >10(6) copies/ml. Nine individuals were HBeAg negative and suspected to harbor HBeAg mutations, while 12 children were HBeAg positive and selected as controls. Ninety percent (19 of 21) of plasma samples tested with molecular beacons were in complete agreement with sequencing results. The remaining 10% (2 of 21) of samples were identified as heterogeneous mixtures of WT and mutant virus by molecular beacons, though sequencing found only a homogeneous mutant in both cases. Overall, the 1896 PC mutation was detected by this assay in 55.5% of the children with HBeAg-negative infection. In summary, this assay is a rapid, sensitive, and specific technique that effectively discriminates WT from 1896 PC mutant HBV and may be useful in clinical and epidemiological studies. 相似文献
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Neulen J; Raczek S; Pogorzelski M; Grunwald K; Yeo TK; Dvorak HF; Weich HA; Breckwoldt M 《Molecular human reproduction》1998,4(3):203-206
Vascularization is a prominent event during corpus luteum formation,
providing low density lipoproteins for steroid biosynthesis and enabling
transport of secreted steroids. The process of vascularization is
controlled by specific regulators. Vascular endothelial growth factor
(VEGF), otherwise named vascular permeability factor (VPF), induces
endothelial cell proliferation as well as angiogenesis in vivo and
increases capillary permeability. Here we report the expression of VEGF/VPF
mRNA by cultured human luteinized granulosa cells (GC) for at least 10
days. Without HCG VEGF/VPF expression declined after day 4 and by day 10
was reduced to approximately 30% of the value at day 4. However, after
culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG),
expression of VEGF/VPF mRNA by GC was four times greater than control
experiments by day 10, and increased 100% from day 4 to day 10.
Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC.
Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium
VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results
suggest that vascularization of the corpus luteum is induced by
HCG-mediated effects of VEGF/VPF.
相似文献
10.
Comparison of Real-Time, Quantitative PCR with Molecular Beacons to Nested PCR and Culture Methods for Detection of Mycobacterium avium subsp. paratuberculosis in Bovine Fecal Samples 下载免费PDF全文
Ying Fang Wai-Hong Wu Jessica L. Pepper Jill L. Larsen Salvatore A. E. Marras Eric. A. Nelson William B. Epperson Jane Christopher-Hennings 《Journal of clinical microbiology》2002,40(1):287-291
An automated PCR with fluorescent probes (molecular beacons) detected Mycobacterium avium subsp. paratuberculosis in bovine feces. When the PCR was compared with culture in testing 41 fecal samples, kappa scores of 0.94 to 0.96, a sensitivity of 93 to 96%, and a specificity of 92% were obtained. Results were quantitated by using a standard curve derived from a plasmid containing IS900. A minimum quantity of 1.7 x 10(-4) pg of DNA, correlating to 1 to 8 CFU, was detected. 相似文献