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101.
Aberrations of genes/proteins regulating cell cycle and growth, increased proliferation and telomerase activity (TA) are documentable in glioblastoma multiforme. TA is more frequently detectable in secondary glioblastoma, which is also characterized by p53 mutation/overexpression. Discordant telomere (Te) length values have been reported in glioblastomas with and without TA. In 31 glioblastomas, in which pre-existing astrocytoma was not documented, we compared cases with and without TA for the expression of p53, EGFR, c-Myc, MIB-1 and Topoisomerase IIalpha; p53 mutations were also investigated by SSCP-PCR. Correlations were made with Te parameters [TePs: number (TeNo), length and area] as evaluated by image analysis in interphase nuclei of fluorescence in situ hybridization (FISH)-processed sections. We found no differences in the expression of the proteins evaluated and in TePs, except Te/nuclear area %, which was significantly lower in TA+ cases (p=0.02). TePs were, instead, inversely correlated with TA (p=0.0001). TA was positively correlated with MIB1 staining index in the TA+ cases (p=0.033), which also showed a positive correlation between TeNo and EGFR expression (p=0.042), and a trend towards a negative correlation between TeNo and p53 expression (p=0.05). Tumors overexpressing EGFR had a significantly shorter lifetime (p=0.0001). TeNo seems to be inversely correlated to tumor proliferation and lifetime in glioblastoma multiforme.  相似文献   
102.
A set of racemic conformationally constrained analogues of the antitumor antibiotic acivicin (+)-1 has been prepared through a strategy based on 1,3-dipolar cycloaddition of bromonitrile oxide to suitable dipolarophiles. The bromo analogue (2) of acivicin was also synthesized and tested as a reference compound, together with its stereoisomer 3. The antitumor properties of novel amino acids 4-7 were evaluated in vitro against human tumor cell lines. Their efficacy to inhibit glutamate synthase (GltS) from Azospirillum brasilense was also assayed. None of the studied compounds, but 2, showed significant activity.  相似文献   
103.
Ninety patients with untreated, stage I-II A myeloma, were randomised to receive or not monthly infusions of pamidronate (PMD) for 1 year, without additional therapies. Follow-up ranged from 36 to 72 months (median 51 months). Three years after the start of the treatment, the disease had progressed in 25% of PMD treated patients and in 26.8% of controls (p n.s). Median time-to-progression was 16 and 17.4 months, respectively (p n.s). Among the 21 patients who required chemo-radiotherapy, skeletal events (osteolytic lesions, pathological fractures and/or hypercalcemia) developed in 9/11 (81.8%) controls and in 4/10 (40%) of treated patients (p < 0.01). "Prophylactic" administration of PMD may decrease the development of skeletal events, but does not reduce the rate and the time of disease progression in early-stage myeloma.  相似文献   
104.
EEG power spectra changes and forebrain ischemia in rats   总被引:5,自引:0,他引:5  
BACKGROUND: Several animal models of cerebral ischemia have been developed to investigate both pathophysiology and pharmacological treatment. The aim of this study was to verify the prognostic value of EEG power spectra analysis in a two-vessel plus hypotension rat model of transient global ischemia. METHODS: Spontaneously hypertensive rats (SHRs) and Wistar Kyoto rats (WKYs) were subjected to 20 min bilateral common carotid artery occlusion plus hypotension by sodium nitroprusside followed by reperfusion for seven days. Sham-operated animals served as controls. The changes after ischemia in EEG power spectra, and their relations with neuronal damage and astrocytic response were investigated. RESULTS: The EEG analysis revealed that in SHRs and WKYs, ischemia produced a dramatic increase in delta activity and a decrease in theta, beta and alpha activities derived from both cortical and hippocampal areas. EEG activity reverted to normal values more quickly in WKYs than in SHRs which did not recover cortical and hippocampal alpha and beta activities even at six days of reperfusion. SHRs presented more severe damage and intense astrocytosis than WKYs in almost all the brain regions analyzed. In SHRs, hippocampal delta activity was positively correlated with the degree of neuronal necrosis and astrocytic activation, whereas theta, alpha and beta activities correlated negatively. No correlations were found in WKYs. CONCLUSIONS: These data indicate that the hippocampal bioelectrical activity recorded in SHRs from the beginning of reperfusion could be useful for predicting the ischemic outcome and evaluating the effects of pharmacological interventions.  相似文献   
105.
The objective of the study was to examine the relationship between HLA genotypes and disease severity as measured by brain MRI quantitative markers of demyelinating and destructive pathology in patients with multiple sclerosis (MS). We studied 100 patients with MS and 122 age, sex-, ethnic- and residence-matched controls. The DNA extraction and the genomic typing (A, B, DRB1 and DQB1 loci) were obtained with sequence-specific oligonucleotide method, using a commercially available reversible line blot assay (INNO-LIPA). All patients underwent a 1.5 tesla MRI examination of the brain. Disease severity was assessed by clinical (Expanded Disability Status Scale (EDSS)) and MRI (T2- and T1-lesion load (LL) and brain parenchymal fraction (BPF)) outcome measures. HLA-DQB1* 02 (OR 19.9, 95% C. I. 16.2–24.3, uncorrected (uncorr)- p<0.00001, corr-p<0.0006), -DQB1*03 (OR 16.8, 95% C. I. 13.6–20.5, uncorr-p<0.00001, corrp< 0.0006), -DRB1*15 (OR 4.6, 95% C. I. 3.7–5.6, uncorrp= 0.0001, corr-p=0.006), and -DRB1*03 (OR 3.9, 95% C. I. 3.2–4.8, uncorr-p=0.0001, corrp= 0.006) alleles were associated with MS. T2-, T1-LL, BPF and EDSS were not significantly different according to the carrier status of these HLA alleles. No differences were found in the ratios of disease severity/disease duration according to the HLA car rier status. Multiple regression analysis showed that a higher T2-LL was associated with the presence of DRB1*04 (uncorr- R2=0.15, p=0.006 and corr- R2=0.11, p=0.025) and B7 alleles (uncorr-R2=0.08, p=0.02 and corr-R2=0.07, p=0.018), T1-LL was associated with B7 (uncorr- R2=0.30, p<0.0001 and corr- R2=0.27, p=0.0001) and DRB1*12 (uncorr-R2=0.25, p<0.0001 and corr-R2=0.21, p=0.0002) alleles, whereas the BPF was predicted only by the presence of DRB1*12 allele (uncorr-R2=0.24, p=0.002 and corr-R2=0.20, p=0.004). The study findings suggest that some HLA alleles may predict the destructive pathological processes visible on MRI. Since the size of the sample studied is relatively small, further studies are needed to draw any firm conclusion about genotype/phenotype correlation in patients with MS.  相似文献   
106.
Epidemiological studies indicate that nonsteroidal anti-inflammatory drugs (NSAIDs) are neuroprotective, although the mechanisms underlying their beneficial effect remain largely unknown. Given their well-known adverse effects, which of the NSAIDs is the best for neurodegenerative disease management remains a matter of debate. Paracetamol is a widely used analgesic/antipyretic drug with low peripheral adverse effects, possibly related to its weak activity as inhibitor of peripheral cyclooxygenase (COX), the main target of NSAIDs. As microglia play an important role in CNS inflammation and pathogenesis of neurodegenerative diseases, we investigate the effect of paracetamol on rat microglial cultures. Although less potent than other NSAIDs, (indomethacin approximately NS-398 > flurbiprofen approximately piroxicam > paracetamol approximately acetylsalicylic acid), paracetamol completely inhibited the synthesis of prostaglandin E(2) (PGE(2)) in lipopolysaccharide-stimulated microglia, when used at concentrations comparable to therapeutic doses. The drug did not affect the expression of the enzymes involved in PGE(2) synthesis, i.e., COX-1, COX-2, and microsomal PGE synthase, or the release of the precursor arachidonic acid (AA). Paracetamol inhibited the conversion of exogenous AA, but not PGH(2), into PGE(2) indicating that the target of the drug is COX activity. Consistently, paracetamol inhibited with similar IC(50) the synthesis of PGF(2alpha) and thromboxane B(2), two other COX metabolites. Finally, none of the NSAIDs affected the productions of nitric oxide and tumor necrosis factor(alpha), two inflammatory mediators released by activated microglia. As paracetamol was reported to inhibit PG synthesis in peripheral macrophages with an IC(50) at least three orders of magnitude higher than in microglia, we suggest that this drug represents a good tool for treating brain inflammation without compromising peripheral PG synthesis.  相似文献   
107.
Reproductive life milestones in women with Parkinson's disease   总被引:2,自引:0,他引:2  
Reproductive life milestones were studied in 150 unselected women with idiopathic Parkinson's disease (PD) and in 300 postmenopausal healthy women (PM). Duration of reproductive life was found to be similar in the two groups. The women with PD reported significantly more premenstrual symptoms, fewer deliveries and abortions, and less use of contraception. Time and mode of menopause onset were similar in PD and PM, but the PD women reported significantly more hot flushes, less insomnia, depression, urinary incontinence and dyspareunia, and less recourse to hormone replacement therapy than the PM women. Women diagnosed with PD before the menopause reported more premenstrual symptoms and contraceptive use compared with those with postmenopausal PD onset, as well as a premenstrual worsening of PD symptoms in more than 50% of cases. Our data indicate poor adaptation of neuronal pathways to the hormonal fluctuations of reproductive life in women with PD, supporting the existence of a qualitative relationship between PD and reproductive events.  相似文献   
108.
A tea tree oil (TTO) preparation of defined chemical composition was studied, using a microbroth method, for its in vitro activity against 115 isolates of Candida albicans, other Candida species and Cryptococcus neoformans. The fungal strains were from HIV-seropositive subjects, or from an established type collection, including reference and quality control strains. Fourteen strains of C. albicans resistant to fluconazole and/or itraconazole were also assessed. The same preparation was also tested in an experimental vaginal infection using fluconazole-itraconazole-susceptible or -resistant strains of C. albicans. TTO was shown to be active in vitro against all tested strains, with MICs ranging from 0.03% (for C. neoformans) to 0.25% (for some strains of C. albicans and other Candida species). Fluconazole- and/or itraconazole-resistant C. albicans isolates had TTO MIC50s and MIC90s of 0.25% and 0.5%, respectively. TTO was highly efficacious in accelerating C. albicans clearance from experimentally infected rat vagina. Three post-challenge doses of TTO (5%) brought about resolution of infection regardless of whether the infecting C. albicans strain was susceptible or resistant to fluconazole. Overall, the use of a reliable animal model of infection has confirmed and extended our data on the therapeutic effectiveness of TTO against fungi, in particular against C. albicans.  相似文献   
109.
PURPOSE: By considering the pathophysiologic basis of inflammatory bowel diseases, a role for excessive lipid peroxidation caused by oxygen free radical compounds has been proposed repeatedly. However, to date only a few studies are available on this topic in human beings. This study was designed to assess breath alkanes in a group of patients with active inflammatory bowel disease by a technique that clearly distinguishes pentane from isoprene, to prevent overestimation of values as in previous studies. PATIENTS: Twenty patients with a diagnosis of active inflammatory bowel disease (10 with Crohn's disease and 10 with ulcerative colitis) were studied. Extension of the disease was similar between patient groups, and all were treated with equivalent doses of steroids and salicylates. METHODS: Breath alkanes determination was performed by a standard procedure involving a gas cromatography column able to separate pentane from isoprene. RESULTS: Overall, significant differences between patients with inflammatory bowel diseases and controls were found for ethane, propane, and pentane, but not for butane and isoprene. Isoprene was clearly distinguished from pentane, demonstrating that the significant elevation of pentane levels in patients with inflammatory bowel diseases is a real phenomenon and not an artifact caused by coelution with isoprene. CONCLUSIONS: An excess of lipid peroxidation is probably an important pathogenetic factor in inflammatory bowel diseases, and this may be assessed through a nonivasive method. Because this method previously also has been shown to be able to evaluate disease activity, it could be a useful tool for studying patients with inflammatory bowel diseases.  相似文献   
110.
Cerebral cavernous malformations (CCMs) are CNS vascular anomalies associated with seizures, headaches and hemorrhagic strokes and represent 10–20% of cerebral lesions. CCM is present in 0.1–0.5 of the population. This disorder most often occurs sporadically but may also be familial. Familial cases are inherited as a dominant trait with incomplete penetrance and are estimated to account for KRIT1 10–40% of the patients. The identification of the genes involved in such disorders allows to characterize carriers of the mutations without clear symptoms. The first gene involved in CCM1 is KRIT1. In addition to two other genes have been described: MGC4607 (CCM2) and PDCD10 (CCM3). We selected 13 patients belonging to seven Sardinian families on the basis of clinical symptoms and Magnetic Resonance results. In MGC4607 gene an undescribed exon five deletion likely producing a truncated protein was identified in one family. In two patients with clear phenotype and in three asymptomatic relatives a 4 bp deletion in exon 9 of KRIT1 gene, leading to a premature stop codon, was detected. A unique nonsense mutation (C329X) has been found in seven patients and two asymptomatic subjects belonging to four unrelated families. Haplotype analysis revealed a common origin of this mutation. These data suggest a “founder effect” in Sardinia for the C329X mutation, similar to other mutations described in different populations.  相似文献   
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