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1.
Almost 90% of primary acute pericarditis are idiopathic. Between specifics forms, a very low percentage of cases are due to chronic rheumatic diseases. A case of adult Still's disease (juvenile chronic rheumatoid arthritis) with acute pericarditis being the first clinical manifestation (besides fever and general syndrome) is presented. Therapy with oral prednisone was rapidly effective, and pericardial effusion resolved after 3 weeks of treatment, as echocardiography showed.  相似文献   
2.
The synthesis and irreversible alpha-blocking activity in the rat vas deferens of a series of tetra- and diamine disulfides 2-38, structural analogues of benextramine (BHC), are described. All compounds containing a central cystamine moiety displayed an irreversible alpha-adrenergic blockade at concentrations ranging from 10(-4) to 6 X 10(-6)M. Potency was increased in cystamines N,N'-disubstituted with 6-aminohexyl groups, especially when the outer nitrogen atoms bear arylalkyl substituents or are enclosed in a ring. However, N,N,N',N'-tetrasubstituted cystamines were poor blockers. Structural specificity in the outer portion of the tetramine disulfide is low, since many types of substituents gave rise to potent alpha-blockers. Even replacement of the outer amines with nonbasic ethers or amides was observed to maintain irreversible alpha-blockade.  相似文献   
3.
Preparations of Amsacta moorei entomopox virions were obtained from virus-containing inclusions (VCI) by using a carbonate-thioglycolate solution (pH 10.7–11.5). The virions possessed a uniform coat (“halo”) surrounding the viral envelope and exhibited an RNA polymerase activity. The “halo” could be removed by prolonged exposure to the carbonate-thioglycolate solution. Virions obtained by this treatment, however, possessed low infectivity and no detectable RNA polymerase activity. Removal of the “halo” by trypsin resulted in virions which possessed RNA polymerase activity and relatively high infectivity.Preparations of particles with and without the “halo” were similar in percent DNA, protein per OD260, number of particles per OD260, and RNA polymerase activity. Particles without the “halo,” however, were less dense (1.262 g/cm3) in CsCl than those with the “halo” (1.282 g/cm3) and 15–45 times more infective.Parallel studies of “nonhaloed” Amsacta virions (trypsin-treated) and vaccinia virions showed that both viruses contained similar amounts of protein per OD260, but Amsacta virions contained only 36% of the DNA found in vaccinia.  相似文献   
4.
Mutations in Bruton’s tyrosine kinase (BTK) gene result in X linked agammaglobulinemia (XLA). Using Single Strand Conformation Polymorphism (SSCP) followed by direct sequencing 21 mutations were found in 27 patients with an XLA phenotype from 21 unrelated families. We identified 13 novel and 8 known mutations: seven missense (R288W, R544G, P566S, K430E; K374N, L512P, R544S), 5 nonsense (Q196X, Y361X, L249X, Q612X, Q466X), 2 deletions of one nucleotide (A207fsX216, Q612fsX648), 2 deletion‐insertions (V219fsX227, K218fsX228), one insertion of two nucleotides (S572fsX587) and 4 point mutations in donor/acceptor splice sites (g.IVS1+1G>C, g.IVS6+5G>A, g.IVS10+1G>T, g.IVS13‐1GG>CT). Carrier detection was performed in 18 mothers. Only in one case the mutation was found to be de novo. Additionally, BTK mutations were not found in four patients without family history, but with XLA‐compatible phenotype. Hum Mutat 18:84, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
5.
Summary.  In this work we present evidence that the homologous peptides IHSMNSTIL and IHSMNSSIL derived from L1 HPV-16 and 18 proteins respectively, and with high specificity for the allele HLA-B*3901, according with an algorithm prediction program, induced T cell stimulation in patients with advanced cervical cancer positive for HPV-16 or 18 infection and for the HLA-B*3901 allele. Interestingly, T lymphocytes derived from a patient with HPV-18 infection and stimulated with the peptide IHSMNSTIL were capable to kill a cervical cancer cell line named Rova, derived from the tumor of the same patient. In addition, the cytotoxic activity was strongly increased when this cell line was previously treated with hrIFN-γ. These results suggest that the CTL immune response to L1 HPV-16 and 18 protein derived epitopes is maintained in patients with advanced cervical cancer within specific alleles, and opens the possibility that homologous epitopes may be used in the generation of prophylactic vaccines for cervical tumors bearing different HPV-types. Received March 4, 2002; accepted May 20, 2002  相似文献   
6.
The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process.  相似文献   
7.
  1. It is well established that 3,4-methylenedioxymethamphetamine (MDMA or ‘ecstasy'') is neurotoxic and produces long term degeneration of cerebral 5-hydroxytryptamine (5-HT) nerve terminals in many species. Since MDMA is used extensively as a recreational drug by young people, it is being ingested by many women of child bearing age. We have therefore examined the effect of administering high doses of MDMA to rats during pregnancy on the cerebral content of both the dams and the neonates.
  2. MDMA (20 mg kg−1, s.c.) was injected twice daily on days 14–17 of the gestation period. The initial dose produced a marked hyperthermic response in the dam which was progressively attenuated in both peak height and area under the curve following further doses of the drug. The body weight of the dams decreased during the period of treatment.
  3. There was a modest decrease in litter size (−20%) of the MDMA-treated dams.
  4. The concentration of 5-HT and its metabolite 5-HIAA was decreased by over 65% in the hippocampus and striatum and 40% in the cortex of the dams 1 week after parturition. In contrast, the content of 5-HT and 5-HIAA in the dorsal telencephalon of the pups of the MDMA-treated dams was the same as that seen in tissue from pups born to control animals.
  5. Administration of MDMA (40 mg kg−1, s.c.) to adult rats increased thiobarbituric acid reacting substances (TBARS) in cortical tissue 3 h and 6 h later, indicating increased lipid peroxidation. No increase in TBARS was seen in the cortical tissue of 7–10 day neonates injected with this dose of MDMA 3 h or 6 h earlier.
  6. The data suggest that exposure to MDMA in utero during the maturation phase does not produce damage to 5-HT nerve terminals in the foetal rat brain, in contrast to the damage seen in the brains of the mothers. This may be due to MDMA being metabolized to free radical producing entities in the adult brain but not in the immature brain or, alternatively, to more effective or more active free radical scavenging mechanisms being present in the immature brain.
  相似文献   
8.
BACKGROUND: The aim of this study was to compare the predictive accuracy for open heart surgical mortality between a statistical model based on collection of clinical data and surgeons' subjective risk assessment. METHODS: Predictive discrimination of both risk assessments (surgeons' and model) was compared through the area under the receiver operating characteristic curve. Logistic regression analysis was used to assess the relation between surgeons' and model predictions to actual outcomes. Calibration of the subjective estimates was evaluated with a chi2 test. RESULTS: Overall, the area under the receiver operating characteristic curve was 0.76 for the statistical model and 0.70 for the subjective assessment. Logistic regression analysis showed that the statistical model remained significant after accounting for the subjective assessment. Calibration of subjective mortality predictions was poor. CONCLUSIONS: Surgeons' risk assessment tends to cluster in the middle ranges of risk. Subjective assessment seems accurate in identifying the two extremes of risk but is inaccurate for intermediate risk levels. A multivariate statistical model improves the accuracy of subjective predictions.  相似文献   
9.
10.
There is evidence of an association between major histocompatibility complex (MHC) genes and acute anterior uveitis; here the authors report the frequency of class I and class III MHC phenotypes in 32 Mexican mestizo patients with chronic anterior uveitis and compared them to those present in 100 ethnically matched healthy controls. Results showed in patients statistically significant increased frequencies of HLA-B(27) antigen (pC=0.02, OR=6.33, 95+ CI:1.63-26.47) and the complotype SC(21) (pC=0.04, OR=4.5, 95+ CI:1.40-14.67); the authors found a decreased frequency of HLA-B(35) (p=0.006, OR=0.10, 95+ CI: 0.00-0.65) as compared to normal controls. None of the individuals bearing the SC(21) complotype were positive for HLA-B(27), suggesting independent roles of the class I and class III antigens in the genetic susceptibility to chronic anterior uveitis.  相似文献   
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