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排序方式: 共有1137条查询结果,搜索用时 414 毫秒
111.
Three patients with viral infections of the central nervous system (CNS) were evaluated on an inpatient infectious diseases consultation service within a two-week period. These cases, caused by herpes simplex virus, varicella zoster virus and enterovirus, highlight the importance of viral pathogens in causing debilitating infections of the CNS and provide examples of the utility of molecular diagnostics in evaluating patients with encephalitis and meningitis. The importance of antiviral therapy is particularly underscored by these cases, as is the variability in response of patients to such agents. 相似文献
112.
Lora J. Kasselman PhD Jeremy M. Shefner MD PhD Seward B. Rutkove MD 《Muscle & nerve》2009,40(1):115-121
Motor unit number estimation (MUNE) of the rodent hindlimb has been used mainly for following the progression of motor neuron disorders. By performing MUNE in the tail, however, progression of axonal neuropathy could also be assessed, as both proximal and distal regions would be available for study. In this investigation, three raters performed a modified multipoint stimulation MUNE technique in the tails of 14 healthy adult rats. The technique was straightforward to perform, with a relatively narrow range of motor unit number estimates of 40 ± 16 (standard deviation) for the proximal tail and 21 ± 11 for the distal tail. Intrarater reliability coefficients were 0.31 (P = 0.033) and 0.32 (P = 0.028) for the proximal and distal tail, respectively. Interrater reliability coefficients were 0.22 (P = 0.086) and 0.44 (P = 0.004). These reliability assessments, along with the relatively low motor unit estimates and narrow range of values, support the idea that rat tail MUNE may have utility in the evaluation of rodent models of neuromuscular disease, including length‐dependent neuropathy. Muscle Nerve 40: 115–121, 2009 相似文献
113.
Ann R. Peden Lynne A. Hall Mary Kay Rayens Lora L. Beebe 《Journal of nursing scholarship》2000,32(2):145-151
Purpose: Although cognitive-behavioral interventions have been successful in treating depression, no studies were found that focused solely on reducing negative thinking via group intervention as a means of preventing depression in at-risk groups. The purpose of this randomized controlled trial was to test the effectiveness of a cognitive-behavioral group intervention in reducing depressive symptoms, decreasing negative thinking, and enhancing self-esteem in young women at risk for depression.
Design: A randomized controlled trial with 92 college women ages 18 to 24 who were at risk for depression was conducted.
Methods: Participants were randomly assigned to either the control or experimental group. The experimental group participated in a 6-week cognitive-behavioral group intervention. Data on self-esteem, depressive symptoms, and negative thinking were collected via selfreport questionnaires from control and experimental groups at baseline, 1 month after the intervention, and at 6-month follow-up. Data were analyzed using mixed-model methodology and the Cochran-Mantel-Haenszel chi-square test.
Findings: Compared to those in the control group, women who received the intervention had a greater decrease in depressive symptoms and negative thinking and a greater increase in self-esteem, and these beneficial effects were maintained over 6-months.
Conclusions: The findings document the effectiveness of this cognitive-behavioral group intervention and indicate empirical support for the beneficial effects of reducing negative thinking by the use of affirmations and thought-stopping techniques on women's mental health. 相似文献
Design: A randomized controlled trial with 92 college women ages 18 to 24 who were at risk for depression was conducted.
Methods: Participants were randomly assigned to either the control or experimental group. The experimental group participated in a 6-week cognitive-behavioral group intervention. Data on self-esteem, depressive symptoms, and negative thinking were collected via selfreport questionnaires from control and experimental groups at baseline, 1 month after the intervention, and at 6-month follow-up. Data were analyzed using mixed-model methodology and the Cochran-Mantel-Haenszel chi-square test.
Findings: Compared to those in the control group, women who received the intervention had a greater decrease in depressive symptoms and negative thinking and a greater increase in self-esteem, and these beneficial effects were maintained over 6-months.
Conclusions: The findings document the effectiveness of this cognitive-behavioral group intervention and indicate empirical support for the beneficial effects of reducing negative thinking by the use of affirmations and thought-stopping techniques on women's mental health. 相似文献
114.
Sanjay Logani Danielle Lu Wim G V Quint Lora H Ellenson Edyta C Pirog 《Modern pathology》2003,16(8):735-741
Histologic criteria of low-grade vulvar/vaginal intraepithelial neoplasia (VIN1/VAIN1) are well established; however, a significant interobserver variability in diagnosing VIN1/VAIN1 has been reported. The goal of this study was to evaluate the utility of MIB-1 immunostaining as an adjunct test to increase the diagnostic accuracy in equivocal cases of VIN1/VAIN1. The second goal was to examine the distribution of low- and high-oncogenic risk human papillomaviruses (HPVs) in VIN1/VAIN1 lesions. Consecutive vulvar/vaginal biopsies originally diagnosed as VIN1/VAIN1 (n = 43) or benign (n = 20) were reviewed by two pathologists to obtain a consensus diagnosis. The diagnosis was further confirmed with HPV testing using Short PCR Fragment 10 and Line Probe Assay. MIB-1 immunostaining was performed, and positive staining was defined as a cluster of two or more stained nuclei in the upper two thirds of the epithelial thickness. After verification of the diagnosis using the consensus histologic review and HPV detection as an objective confirmatory test, 31% of cases originally diagnosed as VIN1/VAIN1 were identified as being overdiagnosed. The sensitivity and the specificity of MIB-1 staining for identifying VIN1/VAIN1 were 0.96 and 0.90, respectively. Seventy percent of VIN1 cases were associated with low-risk viral types. In contrast, the majority (84%) of VAIN1 cases were associated with high-risk HPVs. In conclusion, MIB-1 staining is sensitive and specific for identifying VIN1/VAIN1, helpful in verifying the diagnosis in equivocal cases. 相似文献
115.
We examined the effect of a toxic concentration of allyl alcohol (0.5 mM) on intracellular calcium concentrations in isolated
rat hepatocytes. An increase in phosphorylase a activity was evident in the hepatocytes after 30 min of incubation with allyl alcohol, suggesting that the toxicant may produce
an early rise in cytosolic free calcium. The increase in phosphorylase a activity was not reversed by the addition of dithiothreitol (DTT), a sulfhydryl compound that reverses the events that initiate
cell killing by allyl alcohol. When intracellular calcium concentrations were measured directly, using fura-2 as the calcium
indicator, there was no effect of allyl alcohol on cytosolic free calcium during the first 60 min of exposure, a critical
period for development of irreversible damage. Incubation with allyl alcohol did not interfere with the measurement of intracellular
calcium. The increases in cytosolic free calcium produced by phenylephrine or ATP were similar to those reported by others
and not affected by the presence of allyl alcohol. The results from this study demonstrate that increased cytosolic free calcium
is not essential for allyl alcohol-induced cytotoxicity to isolated rat hepatocytes.
Received: 16 February 1994 / Accepted: 25 May 1994 相似文献
116.
117.
Rountree CB Barsky L Ge S Zhu J Senadheera S Crooks GM 《Stem cells (Dayton, Ohio)》2007,25(10):2419-2429
Although oval cells are postulated to be adult liver stem cells, a well-defined phenotype of a bipotent liver stem cell remains elusive. The heterogeneity of cells within the oval cell fraction has hindered lineage potential studies. Our goal was to identify an enriched population of bipotent oval cells using a combination of flow cytometry and single cell gene expression in conjunction with lineage-specific liver injury models. Expression of cell surface markers on nonparenchymal, nonhematopoietic (CD45-) cells were characterized. Cell populations were isolated by flow cytometry for gene expression studies. 3,5-Diethoxycarbonyl-1,4-dihydrocollidine toxic injury induced cell cycling and expansion specifically in the subpopulation of oval cells in the periportal zone that express CD133. CD133+CD45- cells expressed hepatoblast and stem cell-associated genes, and single cells coexpressed both hepatocyte and cholangiocyte-associated genes, indicating bilineage potential. CD133+CD45- cells proliferated in response to liver injury. Following toxic hepatocyte damage, CD133+CD45- cells demonstrated upregulated expression of the hepatocyte gene Albumin. In contrast, toxic cholangiocyte injury resulted in upregulation of the cholangiocyte gene Ck19. After 21-28 days in culture, CD133+CD45- cells continued to generate cells of both hepatocyte and cholangiocyte lineages. Thus, CD133 expression identifies a population of oval cells in adult murine liver with the gene expression profile and function of primitive, bipotent liver stem cells. In response to lineage-specific injury, these cells demonstrate a lineage-appropriate genetic response. Disclosure of potential conflicts of interest is found at the end of this article. 相似文献
118.
Burke LE Hudson AG Warziski MT Styn MA Music E Elci OU Sereika SM 《The American journal of clinical nutrition》2007,86(3):588-596
BACKGROUND: A vegetarian diet may lead to numerous health benefits, including weight loss. OBJECTIVE: We examined the joint effects of personal preference of dietary treatment and a calorie-restricted, low-fat lactoovovegetarian diet (LOV-D) compared with a standard calorie-restricted, low-fat omnivorous diet (STD-D) on changes in weight, total cholesterol, ratio of LDL to HDL cholesterol (LDL:HDL cholesterol), triacylglycerols, insulin resistance, and macronutrient intake during an 18-mo study. DESIGN: This was a randomized clinical trial of 176 overweight and obese adults who were recruited and randomly assigned first to 1 of 2 preference conditions (yes or no). If assigned to Preference-No, they were randomly assigned to 1 of the 2 diet conditions (STD-D or LOV-D). If assigned to Preference-Yes, they were assigned to the diet they indicated as preferred at screening. The 12-mo intervention was followed by a 6-mo maintenance phase. RESULTS: Participants were mainly women (86.9%) and white (70.5%); 75% completed the 18-mo study. A significant interaction between preference and dietary treatment was not observed for any of the outcome variables. However, participants in the Preference-No groups significantly decreased their triacylglycerols (P = 0.04). The only effect observed for diet was a borderline significant decrease in LDL:HDL cholesterol for the LOV-D group (P = 0.06). Within the LOV-D groups, those who were 100% adherent to the LOV-D had significant and marginally significant reductions in monounsaturated fat (P = 0.02) and total fat (P = 0.05) intakes at 18 mo. CONCLUSIONS: Our findings suggest that neither prescribing a vegetarian diet nor allowing persons to choose their preferred diet had a significant effect on outcome measures. However, all participants had a significant reduction in total energy and fat intakes and an increase in energy expenditure, which was reflected in reduced body weight. This clinical trial was registered at www.clinicaltrials.gov as NCT00330629. 相似文献
119.
Crystal structures of Escherichia coli topoisomerase IV ParE subunit (24 and 43 kilodaltons): a single residue dictates differences in novobiocin potency against topoisomerase IV and DNA gyrase
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Bellon S Parsons JD Wei Y Hayakawa K Swenson LL Charifson PS Lippke JA Aldape R Gross CH 《Antimicrobial agents and chemotherapy》2004,48(5):1856-1864
Topoisomerase IV and DNA gyrase are related bacterial type II topoisomerases that utilize the free energy from ATP hydrolysis to catalyze topological changes in the bacterial genome. The essential function of DNA gyrase is the introduction of negative DNA supercoils into the genome, whereas the essential function of topoisomerase IV is to decatenate daughter chromosomes following replication. Here, we report the crystal structures of a 43-kDa N-terminal fragment of Escherichia coli topoisomerase IV ParE subunit complexed with adenylyl-imidodiphosphate at 2.0-A resolution and a 24-kDa N-terminal fragment of the ParE subunit complexed with novobiocin at 2.1-A resolution. The solved ParE structures are strikingly similar to the known gyrase B (GyrB) subunit structures. We also identified single-position equivalent amino acid residues in ParE (M74) and in GyrB (I78) that, when exchanged, increased the potency of novobiocin against topoisomerase IV by nearly 20-fold (to 12 nM). The corresponding exchange in gyrase (I78 M) yielded a 20-fold decrease in the potency of novobiocin (to 1.0 micro M). These data offer an explanation for the observation that novobiocin is significantly less potent against topoisomerase IV than against DNA gyrase. Additionally, the enzyme kinetic parameters were affected. In gyrase, the ATP K(m) increased approximately 5-fold and the V(max) decreased approximately 30%. In contrast, the topoisomerase IV ATP K(m) decreased by a factor of 6, and the V(max) increased approximately 2-fold from the wild-type values. These data demonstrate that the ParE M74 and GyrB I78 side chains impart opposite effects on the enzyme's substrate affinity and catalytic efficiency. 相似文献
120.
Dunbar-Jacob J Holmes JL Sereika S Kwoh CK Burke LE Starz TW McCall M Foley SM 《Arthritis and rheumatism》2004,51(3):422-428
OBJECTIVE: To examine factors contributing to the loss of potential minority participants in a study of medication adherence among rheumatoid arthritis patients. METHODS: Chi-square statistics were used to test for differences in refusal/ineligibility by race and site at 4 screening points (initial eligibility review, initial patient contact, adherence screening, and informed consent). Differences in criteria-specific risks for exclusion at initial eligibility review were examined across 4 sites by race. Odds ratios (95% confidence intervals) were estimated if differences were significant. Multivariate logistic regression was used to examine sociodemographic factors associated with the probability for ineligibility at the initial eligibility review. Stated reasons for refusal were qualitatively quantified. RESULTS: A greater percentage of African Americans were lost at every screening point when compared with whites, but only the difference at the initial eligibility review was statistically significant. CONCLUSION: Factors associated with attrition included selection of area medical sites, research design issues, comorbid conditions, alcohol abuse, and being younger, unmarried, African American, and male. 相似文献