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11.
Summary Extracellular single-neuron recordings were obtained from electrophysiologically identified nigrostriatal neurons in chloral hydrate anesthetized rats, in order to test the hypothesis that excitatory amino acid receptors are involved in responses of these neurons to electrical stimulation of the pontine region where the pedunculopontine nucleus (PPN) is located. The effects of iontophoretic application of excitatory amino acids and their antagonists as well as of cholinergic antagonists were tested on the fast orthodromic excitation of nigrostriatal neurons evoked by stimulation of the PPN region. The N-methyl-D-aspartate (NMDA) receptor antagonist D-a-aminoadipic acid as well as the cholinergic receptor antagonists mecamylamine and atropine failed to suppress the synaptic excitation of nigral neurons. The NMDA receptor antagonist DL-2-amino-5-phosphonovalerate exerted a weak depressant action on the synaptic response in a few neurons only. On the contrary, the broad spectrum antagonists of excitatory amino acid receptors kynurenic acid and gamma-Dglutamyl-amino-methyl-sulphonate were found to block simultaneously both the synaptic excitation and the neuronal responses to iontophoretic pulses of glutamate while leaving unaffected the neuronal responses to local application of acetylcholine or carbachol. The competitive antagonist of non-NMDA receptors 6-cyano-2,3-dihy-droxy-7-nitro-quinoxaline suppressed the synaptic excitation at ejection currents which antagonized neuronal responses to quisqualate and kainate. These results suggest that PPN excitatory fibers synapsing onto pars compacta nigrostriatal neurons utilize an excitatory amino acid as a synaptic transmitter acting preferentially on non-NMDA receptors.  相似文献   
12.
The genetic basis of myotonic dystrophy type 1 (DM1) is the expansion of a CTG repeat in the 3' untranslated region of DM1PK. Once into the disease range, the repeat becomes highly unstable and is biased toward expansion in both somatic and germline tissues. Intergenerational differences usually reveal an increase in allele length, concordant with the clinical anticipation characteristic of DM1, but there have also been cases with intergenerational contractions of the repeat length, accompanied by apparent anticipation. In order to gain a better understanding of this intergenerational behaviour, we have obtained semen samples from six DM males and used single molecule analyses to compare the allele distributions present in their sperm and blood with those of their offspring. We have confirmed that the male germline mutational pathway is distinct from that of the soma, but the extent of variation is highly variable from one individual to another and not obviously correlated with progenitor allele length. Nonetheless, in all cases the alleles present in the father's sperm overlap with those observed in their offspring. These data also provide further indications that the interpretation of intergenerational transmissions by standard analyses is frequently compromised by the masking of germline differences by age-dependent somatic expansion in the parent.  相似文献   
13.
B cell lymphoma of the thymus and salivary gland.   总被引:2,自引:0,他引:2       下载免费PDF全文
A case of primary low grade B cell lymphoma of the salivary gland associated with a low grade B cell lymphoma of the thymus and involvement of the skin is reported. The lesions in the salivary gland and in the thymus showed the typical features of a lymphoma arising from the mucosa associated lymphoid tissue (MALT) and comprised lymphatic follicles, centrocyte-like (CCL) cells and lymphoepithelial lesions. Immunohistochemistry and Southern blot analysis supported the hypothesis that these lesions can originate from the same cellular clone. These findings confirm the occurrence of low grade B cell MALT lymphoma in the thymus and the possibility of spread of MALT lymphoma to other mucosal sites.  相似文献   
14.
It has long been debated whether endothelial cells are present at very low frequency in peripheral blood. Elevated concentrations of such circulating cells may represent a good marker of vascular injury. We have therefore designed an immunocytometric assay for the detection of rare endothelial cells in whole blood. This assay is based on a new monoclonal antibody (MAb) S-Endo 1, made against human umbilical vein endothelial cells (HUVEC) and specific for endothelial cells of various origins without detectable reactivity with blood cells. First, the sensitivity of the assay was established by using normal blood samples with admixed HUVEC as an in vitro model. A good correlation was obtained between added and counted endothelial cells; the recovery was greater than 90% and the minimum detectable concentration of HUVEC was about 0.2 cells/microliters whole blood. Using this rapid counting technique, no detectable levels of endothelial cells were found in the blood of normal individuals (CE less than or equal to 0.1 cells/microliters) while elevated concentrations (up to 8 cells/microliters) were detected in a human model of vascular injury corresponding to a traumatic venepuncture. Thus, this new whole blood immunocytometric assay using S-Endo 1 MAb may be useful in determining the levels of circulating endothelial cells in vascular disorders.  相似文献   
15.
16.
We report the identification of a new DRB1* allele in a Spanish Caucasoid family during a search for a histocompatible bone marrow donor. This novel allele, designated as DRB1*1145, differs from DRB1*1123 in one nucleotide at position 199 in exon 2 (A replacing T), leading to one amino acid change from phenylalanine (Phe) to isoleucine (Ile) at codon 67. The propositus's father had identical class II alleles but showed a minor mismatch at locus B (B*4403 by B*4402) and a C-locus mismatch (Cw*1502 by Cw*0501). We discuss the criteria of selecting a non-related bone marrow donor with a minor mismatch on the DRB1* allele or the related father having a minor mismatch at B locus and a C-locus mismatch.  相似文献   
17.
Multiple prognostic indicators, namely histological grade and immunostaining for estrogen (ER) and progesterone receptors (PgR), MIB 1, bc1-2, and p53, were retrospectively determined on preoperative core biopsies from 75 patients with pT 1 breast carcinoma. The association of the preoperatively evaluated factors with those on the corresponding resected tumors (i.e. nodal status, histological grade, presence or absence of vascular invasion and necrosis) was assessed. In univariate analysis, histological grade on resected tumors was significantly associated with histological grade on core biopsy, p53 expression, MIB1 immunostaining. An inverse association was found between postoperative histologic grade and ER, PgR, and bc1-2. Necrosis was significantly associated with grade, p53, MIB1, and inversely with ER, PgR, and bc1-2. Nodal involvement and vascular invasion were significantly associated with MIB1. In multivariate analysis, histological grade and ER were the only independent core biopsy variables associated with postoperative histological grade and necrosis, respectively. This study showed that image-guided core biopsy is a suitable method that can be used to reveal some characteristics of the tumor biology in a preoperative stage.  相似文献   
18.
Background: The non-Hodgkins lymphoma (NHL) subgroup most frequentlyassociated with hepatitis C virus (HCV) infection is the lymphoplasmacytoidlymphoma/immunocytoma (Lp-Ic). We have assessed the impact of the infectionon the clinical features, quality of life and survival of HCV+ve Lp-Icpatients as compared to its impact in HCV–ve patients.Patients and methods: Seventy patients with Lp-Ic consecutively observedover a six-year period were studied. Clinical, virological andhistopathological features were recorded at diagnosis. Quality of life wasassessed using a scoring system including disease-related symptoms,performance status, working ability, hospital admissions and therapiesrequired.Results: Eighteen patients (26%) with HCV infection wereidentified. Significant differences between those patients and theHCV–ve group included number of symptomatic patients, Hb levels, serumprotein levels, entity of the IgM monoclonal component, number of patientswith cryoglobulins and with organ (liver, kidney) involvement, and entityand pattern of bone marrow infiltration. Survival rates were similar (P =0.8383), but the quality-of-life score was significantly worse for theHCV+ve patients (P = 0.002). All anti-HCV Ab+ve patients tested positive forHCV RNA; genotype 2ac was detected in a significant proportion of cases.Conclusions: This study confirms that HCV infection is present in aboutone-third of patients with Lp-Ic. HCV infection does not seem to affect theoverall survival of patients with Lp-Ic, but it affects the clinicalexpression of the disease, so that the overall quality of life of HCV+vepatients is significantly worse.  相似文献   
19.
BACKGROUND: The purpose of the study was to verify the effectiveness of tramadol in the treatment of non-oncologic chronic pain, oncologic chronic pain and postoperative acute pain, applying the principles of meta-analytic analysis to randomized clinical trials (TCR). METHODS: I: Medline research of the TCR on the question in the period between 1989-1999, II: exclusion of single TCR through the question of Moore and Mcquay; calculation of the relative risk reduction (RRR), of the number needed to treat (NNT), of the odds ratio (OR) and of the typical odds ratio (TOR) of the trials which responded to characteristics of correct randomization and blindness, which expressed citation of the patients excluded from trial, and patients with measurable analgesic effectiveness (number of patients with reduction of the pain intensity 50%). RESULTS: 52 trials extracted from Medline: 10 on the treatment of non-oncologic chronic pain, 36 on the treatment of postoperative acute pain and 6 on the treatment of oncologic chronic pain. Responded fully to requirements: 8 studies (3 for non-oncologic chronic pain, 3 for postoperative acute pain and 2 for oncologic pain). The OR was 0.55 (-0.31/1.41); 0.44 (1.04/1.92) and 0.98 (0.5/1.46); the RRR was 0.26 (-0.19/0.71), 0.38 (0.15/0.61), 0.005 (0.19/0.20) and the NNT 6.6 (6.39/6.81), 5.26 (5.12/5.4), infinity in the 3 trials selected between those that concern the treatment of the nononcologic chronic pain (with TOR: 0.57 and confidence index: 0.23-0.9); the OR was 0.36 (1.06/1.78), 0.78 (-0.08/-1.64) and 1.12 (0.54/1.69); the RRR was 0.26 (-0.18/0.7), 0.07 (-0.2/0.35), -0.01 (-0.09/0.07) and the NNT 4.7 (4.42/4.58), 20 (19.8/20.20), infinity in the trials on the treatment of postoperative acute pain (with TOR: 0.4 and confidence index: -0.6-0.86); the OR was 0.53 (-0.67/1.73), 0.27 (-0.71/1.12); the RRR was 0.19 (-0.33/0.72), 0.35 (0.02/0.68) and the NNT 7.1 (6.78/7.42), 3.57 (3.37/3.76) in those that involved the treatment of oncologic chronic pain (with TOR: 0.49 and confidence index: 0.36-0.8). CONCLUSIONS: Although the short number of trials which can treated by the metanalytic technique the treatment with tramadol, compared comparison's to drugs (morphine, pentazocine, bupremorphine, etc.) determined a slight improvement in analgesic parameters or at least in analgesic effectiveness.  相似文献   
20.
PURPOSE: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. EXPERIMENTAL DESIGN: Tumor pieces (2 x 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21(Cip1), p27(Kip1), p16(INK4a), pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. RESULTS: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27(kip1) overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete alpha-fetoprotein, and has TP53 missense mutations in codons 192 and 242. CONCLUSIONS: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.  相似文献   
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