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Background: The authors conducted a double-blind, randomized, controlled trial to determine whether the use of sevoflurane in children undergoing anesthesia and surgery results in a higher incidence of postoperative maladaptive behavioral changes as compared with halothane.

Methods: Children and their parents (n = 102) were randomly assigned to either a halothane group (n = 50) or a sevoflurane group (n = 52). The intraoperative anesthetic protocol was strictly controlled, and the postoperative analgesic consumption and pain levels were recorded. The effect of the group assignment on emergence status and maladaptive postoperative behavioral changes was assessed both by validated psychological measures and physiologic instruments (actigraphy) on postoperative days 1-7. Anxiety of the parent and child was also assessed, as was the child's postoperative recovery (Recovery Inventory).

Results: There were no group differences in preoperative state anxiety, postoperative analgesic requirements, postoperative pain, or the incidence of emergence delirium (P = not significant). Two-way repeated-measures analysis of variance showed no group differences in the incidence of postoperative maladaptive behaviors (F4,72 = 0.60, P = 0.701) or actigraphic variables such as percent sleep, number of night awakenings, and night awakenings that lasted for more than 5 min (P = not significant).  相似文献   

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We present an analysis of rates and patterns of microevolutionary phenomena that have shaped the human, mouse, and rat genomes since their last common ancestor. We find evidence for a shift in the mutational spectrum between the mouse and rat lineages, with the net effect being a relative increase in GC content in the rat genome. Our estimate for the neutral point substitution rate separating the two rodents is 0.196 substitutions per site, and 0.65 substitutions per site for the tree relating all three mammals. Small insertions and deletions of 1-10 bp in length ("microindels") occur at approximately 5% of the point substitution rate. Inferred regional correlations in evolutionary rates between lineages and between types of sites support the idea that rates of evolution are influenced by local genomic or cell biological context. No substantial correlations between rates of point substitutions and rates of microindels are found, however, implying that the influences that affect these processes are distinct. Finally, we have identified those regions in the human genome that are evolving slowly, which are likely to include functional elements important to human biology. At least 5% of the human genome is under substantial constraint, most of which is noncoding.  相似文献   
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We have reported associations between human leukocyte antigen (HLA) homozygosity and low measles antibody levels after one dose of the measles, mumps, and rubella (MMR) vaccine. Here, we examined associations between HLA homozygosity and immune responses to MMR after two doses of vaccine. We examined associations between HLA homozygosity and measles antibody levels in a group of 178 children (cohort 1) as well as associations between homozygosity and antibody levels and lymphoproliferative responses to MMR in 346 children (cohort 2). In cohort 1, HLA homozygotes and heterozygotes had similar increases in measles antibody levels after a second dose of measles vaccine. In cohort 2, HLA homozygosity was not associated with measles immune measures after two doses of vaccine. Homozygosity at the DPB locus was associated with increased rubella antibody levels, and homozygosity at the class IA alleles was associated with lower mumps lymphoproliferative response. Homozygosity at increasing numbers of loci was also associated with lower mumps antibody levels and lymphoproliferative response. Therefore, two doses of the MMR vaccine appear to induce sufficient antibody levels and lymphoproliferative responses against measles and rubella, regardless of HLA homozygosity status. However, children who are HLA homozygous may be less protected against mumps compared with children who are heterozygous.  相似文献   
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The protective effect of measles immunization is due to humoral and cell-mediated immune responses. Little is known about cell-mediated immunity (CMI) to measles vaccine virus, the relative contribution of CD4(+) and CD8(+) T cells to variability in such immune responses, and the immunologic longevity of the CMI after measles vaccination in humans. Our study characterizes cellular immune response in subjects seronegative or highly seropositive for measles vaccine immunoglobulin G-specific antibody, aged 15 to 25 years, previously immunized with two doses of measles-mumps-rubella II vaccine. We evaluated the ability of subjects to respond to measles vaccine virus by measuring measles virus-specific T-cell proliferation. We examined the frequencies of measles virus-specific memory Th1 and Th2 cells by an ELISPOT assay. Our results demonstrated that proliferation of T cells in seronegative subjects was significantly lower than that for highly seropositive subjects (P = 0.003). Gamma interferon (IFN-gamma) secretion predominated over interleukin 4 (IL-4) secretion in response to measles virus in both groups. The median frequency of measles virus-reactive CD8(+) T cells secreting IFN-gamma was 0.09% in seronegative subjects and 0.43% in highly seropositive subjects (P = 0.04). The median frequency of CD4(+) T cells secreting IL-4 in response to measles virus was 0.03% in seronegative subjects and 0.09% in highly seropositive subjects (P = 0.005). These data confirm the presence of measles virus-specific cellular immune responses post-measles vaccine immunization in humans. The detection of measles virus-induced IFN-gamma and IL-4 production by ELISPOT can be used to identify measles virus-specific low-frequency memory T cells in subjects immunized with measles vaccine. These differences agree in directionality with the observed antibody response phenotype.  相似文献   
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Pain sensitivity varies substantially among humans. A significantpart of the human population develops chronic pain conditionsthat are characterized by heightened pain sensitivity. We identifiedthree genetic variants (haplotypes) of the gene encoding catecholamine-O-methyltransferase(COMT) that we designated as low pain sensitivity (LPS), averagepain sensitivity (APS) and high pain sensitivity (HPS). We showthat these haplotypes encompass 96% of the human population,and five combinations of these haplotypes are strongly associated(P=0.0004) with variation in the sensitivity to experimentalpain. The presence of even a single LPS haplotype diminishes,by as much as 2.3 times, the risk of developing myogenous temporomandibularjoint disorder (TMD), a common musculoskeletal pain condition.The LPS haplotype produces much higher levels of COMT enzymaticactivity when compared with the APS or HPS haplotypes. Inhibitionof COMT in the rat results in a profound increase in pain sensitivity.Thus, COMT activity substantially influences pain sensitivity,and the three major haplotypes determine COMT activity in humansthat inversely correlates with pain sensitivity and the riskof developing TMD.  相似文献   
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BACKGROUND: AbobotulinumtoxinA (AboBoNT-A; Dysport®; Ipsen, Boulogne-Billancourt, France/Azzalure®; Galderma, Lausanne, Switzerland) is a botulinum neurotoxin type A approved for aesthetic use in the treatment of glabellar lines in adult patients under 65 years in Europe, the United States, and other countries. OBJECTIVE: We sought to analyze current literature on patient satisfaction with aboBoNT-A for upper facial aesthetic indications. METHODS: A systematic review of literature databases (PubMed/MEDLINE, Embase, the Cochrane Library, and Google Scholar) was performed to identify English-language publications reporting on patients with aesthetic indications (including glabellar lines and wrinkles) receiving aboBoNT-A, that assessed patient and/or physician satisfaction with treatment, with no restrictions on comparator studies. Structured data extraction was used to enable inter-study analysis. A post-hoc analysis was also performed to assess patient satisfaction by sex and age, using results from the noninterventional APPEAL study of patients’ satisfaction with aboBoNT-A for treating glabellar lines. RESULTS: Overall, 22 original research papers were identified. Patient satisfaction rates for aboBoNT-A treatment were significantly higher versus placebo from two weeks to between three and five months postinjection. At two to three weeks postinjection, patient satisfaction rates were 52% and 99% across studies. In studies with later time points, patient satisfaction rates were 85 to 87 percent at 5 months and between 25 and 100 percent at 6 months post-injection. Physician satisfaction was also high (97%–100%, across three treatments). No notable differences in patient satisfaction by sex or age were observed in the APPEAL study. CONCLUSION: High rates of patient satisfaction have been achieved with aboBoNT-A treatment for upper facial aesthetic indications. Despite the current recommended interval of ≥12 weeks, satisfaction with the aesthetic results of aboBoNT-A therapy is still evident up to 6 months post-injection in some patients.  相似文献   
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We have determined the effects of myosin binding protein-C (MyBP-C) and its domains on the microsecond rotational dynamics of actin, detected by time-resolved phosphorescence anisotropy (TPA). MyBP-C is a multidomain modulator of striated muscle contraction, interacting with myosin, titin, and possibly actin. Cardiac and slow skeletal MyBP-C are known substrates for protein kinase-A (PKA), and phosphorylation of the cardiac isoform alters contractile properties and myofilament structure. To determine the effects of MyBP-C on actin structural dynamics, we labeled actin at C374 with a phosphorescent dye and performed TPA experiments. The interaction of all three MyBP-C isoforms with actin increased the final anisotropy of the TPA decay, indicating restriction of the amplitude of actin torsional flexibility by 15–20° at saturation of the TPA effect. PKA phosphorylation of slow skeletal and cardiac MyBP-C relieved the restriction of torsional amplitude but also decreased the rate of torsional motion. In the case of fast skeletal MyBP-C, its effect on actin dynamics was unchanged by phosphorylation. The isolated C-terminal half of cardiac MyBP-C (C5–C10) had effects similar to those of the full-length protein, and it bound actin more tightly than the N-terminal half (C0–C4), which had smaller effects on actin dynamics that were independent of PKA phosphorylation. We propose that these MyBP-C-induced changes in actin dynamics play a role in the functional effects of MyBP-C on the actin–myosin interaction.  相似文献   
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