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171.
Computer-assisted image analysis is useful for quantifying the histologic and molecular changes of sun-induced squamous cell carcinoma progression. We used the CAS 200 image analysis system to measure nuclear morphometric parameters, p53 expression, and proliferation markers in actinic keratosis (AK), sun-exposed, and normal skin in 51 patients. Nuclear morphometry revealed significant increases in nuclear absorbance, irregularity of nuclear shape, and nuclear size in AK compared with normal and sun-damaged skin. These parameters showed significantly greater variability in AK nuclei. Argyrophyllic nucleolar organizer area and number were also significantly greater in AK compared with sun-damaged skin and normal skin. Ki67 and p53 expressions were both increased in sun-damaged skin relative to normal and greater still in AK. These data are evidence that sun damage induces proliferation and p53 abnormalities before the appearance of nuclear abnormalities and their associated DNA instability. Following these changes during a skin cancer chemopreventative trial can then help assess the efficacy of the agent and help determine where in the progression of neoplastic changes it exerts its biological effects.  相似文献   
172.
PURPOSE: To determine the antitumor activity of ABX-EGF, a fully human monoclonal antibody to the epidermal growth factor receptor (EGFr), in previously treated patients with metastatic renal cell carcinoma, and to characterize its toxicity, immunogenicity, pharmacokinetics, and pharmacodynamics. PATIENTS AND METHODS: The antitumor activity, as well as the toxicity, pharmacokinetics, pharmacodynamics, and immunogenicity of ABX-EGF, were assessed. RESULTS: Eighty-eight patients were treated with ABX-EGF doses of 1.0, 1.5, 2.0, or 2.5 mg/kg weekly with no loading dose. EGFr immunostaining was performed on 76 tumor biopsy specimens (86%), and 69 (91%) scored positive. Major responses occurred in three patients, and two patients had minor responses. Forty-four patients (50%) also had stable disease at their first 8-week assessment, and the median progression-free survival (PFS) was 100 days (95% CI, 58 to 140 days). Low hemoglobin and high alkaline phosphatase predicted for short PFS. The principal toxicity, an acneiform rash, occurred in 68%, 95%, 87%, and 100% of patients who received at least three doses of ABX-EGF at 1.0, 1.5, 2.0, and 2.5 mg/kg/wk, respectively. A trend indicated that the severity of the rash may relate to PFS. No human antihuman antibodies were detected. ABX-EGF pharmacokinetics fit a model that incorporated both linear and saturable EGFr-mediated clearance mechanisms, and interindividual variability was low. At 2.5 mg/kg/wk, ABX-EGF concentrations throughout treatment exceeded those estimated to saturate nonlinear clearance and inhibit xenograft growth by 90%. CONCLUSION: ABX-EGF was generally well tolerated. The objective response rate was low in previously treated patients with metastatic renal cell carcinoma. Although skin rash may be a pharmacodynamic marker of drug action, its potential as a surrogate marker of clinical benefit requires further evaluation.  相似文献   
173.
PURPOSE: Imatinib mesylate is a tyrosine kinase inhibitor with high affinity for the BCR-ABL fusion protein expressed by the hematopoietic cells in chronic myelogenous leukemia (CML). Some patients with chronic-phase or accelerated-phase CML either relapse after an initial response or are refractory to imatinib, prompting us to evaluate the efficacy of dose increase in such patients. EXPERIMENTAL DESIGN: Twelve chronic-phase patients initially receiving 400 mg/day and 4 patients with accelerated phase initially receiving either 400 mg/day (two patients) or 600 mg/day (two patients) had their dose increased (14 to 800 mg/day and 2 to 600 mg/day) because of progressive disease (usually clonal evolution) or inadequate cytogenetic response after at least 1 year of therapy. RESULTS: Six patients had major cytogenetic responses after dose increase (3 complete and 3 partial). Two others had minor cytogenetic responses. Two patients with clonal evolution transiently lost the additional clonal aberrations. Almost all of the responses occurred within 6 months, and were typically 3-6 months in duration. However, 3 patients have continuing major cytogenetic responses of >18 months duration. Dose increase was well tolerated, with thrombocytopenia, mild leukopenia, and exacerbation of prior edema being the most common adverse events. CONCLUSIONS: Although increasing the dose of imatinib can benefit a subgroup of patients with CML with either an inadequate cytogenetic response or disease progression, our results suggest the majority will not have a sustained meaningful response, and that other options, such as allogeneic stem cell transplant or investigational therapies, also need to be considered at the time of dose increase.  相似文献   
174.
Women with advanced breast cancer frequently experience psychologic distress as a result of their illness and its treatment. This distress may be manifest as depression, anxiety, symptoms of the stress-response syndrome, difficulty coping and social isolation. Six randomized trials of psychosocial interventions have been conducted in metastatic breast cancer. Five of these evaluated group psychosocial support – supportive-expressive therapy in three studies, cognitive-behavioral in one, and a combination of cognitive-behavioral and supportive therapy in another. All of these studies identified psychological benefits, notably improvement in mood, pain control and coping, although benefits were small in one study that provided the control group with a home cognitive-behavioral study program. One study identified an unexpected survival benefit associated with a group intervention – three subsequent studies have failed to replicate this result. Survival results of one additional ongoing study are pending.Studies in early breast cancer, and in patients with a spectrum of other cancers, have demonstrated benefits of individual psychological interventions, educational interventions and relaxation/self-hypnosis/imagery interventions, however, these have not been adequately evaluated in metastatic breast cancer.Based on these results, it is recommended that psychosocial support be offered to women with advanced breast cancer. Current research does not provide sufficient information to determine the optimal type of intervention to be used, or the optimal timing and duration of such interventions. Furthermore, it is not clear which patients benefit the most from psychosocial intervention and whether there are some patients who do not require psychosocial intervention. Research to address these issues is recommended.  相似文献   
175.
Interleukin-8 (IL-8), a potent neutrophilic chemoattractant and inflammatory cytokine, is present in middle ear effusions (MEEs) of children with otitis media and is thought to be responsible for the accumulation of neutrophils in MEEs. We hypothesized that IL-8 concentration predicts the total number and proportion of neutrophils in MEEs. IL-8 concentration and total and differential cell counts were measured in MEEs of children undergoing tympanostomy tube placement for otitis media. IL-8 was present in 80 (98%) of 82 effusions. The mean ± SEM value for IL-8 was 7342 ± 847 pg/mL. The mean ± SEM count and percentage of neutrophils were 1.34 × 106 ± 3.44 × 105 and 70.6 ± 3.1%, respectively. IL-8 concentrations correlated positively with the total number(r = +0.30; P = 0.02) and percentage of neutrophils(r= +0.32; P = 0.01) in the effusion. Additionally, purulent effusions had greater IL-8 concentrations (P = 0.003) and greater neutrophil count (P = 0.03) than mucoid or serous effusions. We conclude that IL-8 is consistently present in MEEs of children and IL-8 concentration predicts the total number and proportion of neutrophils. Furthermore, IL-8 concentration and the total number of neutrophils correlate positively with the type of effusion. These results support the hypothesis that IL-8 recruits neutrophils to the middle ear in MEEs.  相似文献   
176.
Systemic Lupus Erythematosus: Perinatal and Neonatal Implications   总被引:2,自引:0,他引:2  
Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that can affect almost all organ systems in the body. It is most common in women of childbearing age and may cause multiple peripartum complications. This article reviews the pathophysiology of SLE and the effects of SLE on fertility and pregnancy. The complexities of managing a pregnant patient with SLE are reviewed, and the importance of interdisciplinary collaboration discussed, as well as the effects of SLE on the fetus and a review of neonatal lupus erythematosus. Finally, a case report of a pregnant patient with SLE with challenging clinical management issues is presented.  相似文献   
177.
178.
OBJECTIVE: To determine if differences between English- and Spanish-speaking parents in ratings of their children's health care can be explained by need for interpretive services. METHODS: Using the Consumer Assessment of Health Plans Survey-Child-Survey (CAHPS), reports about provider communication were compared among 3 groups of parents enrolled in a Medicaid managed care health plan: 1) English speakers, 2) Spanish speakers with no self-reported need for interpretive services, and 3) Spanish speakers with self-reported need for interpretive services. Parents were asked to report how well their providers 1) listened carefully to what was being said, 2) explained things in a way that could be understood, 3) respected their comments and concerns, and 4) spent enough time during medical encounters. Multivariate logistic regression was used to compare the ratings of each of the 3 groups while controlling for child's gender, parent's gender, parent's educational attainment, child's health status, and survey year. RESULTS: Spanish-speaking parents in need of interpretive services were less likely to report that providers spent enough time with their children (odds ratio = 0.34, 95% confidence interval = 0.17-0.68) compared to English-speaking parents. There was no statistically significant difference found between Spanish-speaking parents with no need of interpretive services and English-speaking parents. CONCLUSIONS: Among Spanish- versus English-speaking parents, differences in ratings of whether providers spent enough time with children during medical encounters appear to be explained, in part, by need for interpretive services. No other differences in ratings of provider communication were found.  相似文献   
179.
OBJECTIVE: Recent studies of ovarian cancer have suggested a role for inflammation in carcinogenesis. Data from a population-based case-control study in Hawaii were examined to assess the relation between polymorphisms in cytokines involved with the inflammatory response, specifically members of the interleukin (IL) family and the incidence of ovarian cancer. PATIENTS AND METHODS: The analysis of 182 epithelial ovarian cancer cases and 219 controls focused on the polymorphisms in the following genes: IL-1alpha, IL-1beta, IL-6, IL-10, and IL-18. Genotype data were obtained from blood samples collected in participants' homes, and reproductive, demographic, and lifestyle histories were collected during interview. RESULTS: There were no significant odds ratios (ORs) for ovarian cancer by allelic variants in any of the IL genes after adjusting for age, ethnicity, education, oral contraceptive pill use, pregnancy, and history of tubal ligation. Although there was a significantly reduced risk of ovarian cancer risk among women with an IL-1alpha (-4845) T allele compared to women with two G alleles (OR: 0.59; 95% confidence interval: 0.37-0.97) after adjustment for age and ethnicity, the trend was not significant (p = 0.10). Further examination of the data suggested that women with at least one IL-18 variant allele (a G to C transition at position -137) were at significantly decreased risk of advanced ovarian cancer (OR: 0.51; 95% confidence interval: 0.28-0.90) compared to women with the IL-18 GG genotype. There was a significant difference in the risk of ovarian cancer associated with the IL-18 C allele by stage at diagnosis (p = 0.04 for homogeneity in the ORs): cases with IL-18 GC or CC genotypes were less likely to be diagnosed at regional/distant stages. Analysis of the data within ethnic subgroups revealed a significant positive association of the heterozygous IL-18 GC genotype with ovarian cancer risk among Native Hawaiian women (OR: 9.96; 95% CI: 1.88-52.90). The OR for ovarian cancer was not significant for Native Hawaiian women homozygous for the IL-18 C allele, but only one case and control had the IL-18 CC genotype. CONCLUSIONS: Overall, this study does not support an association of selected IL-1alpha, IL-1beta, IL-6, IL-10, or IL-18 polymorphisms with the risk for ovarian cancer. However, the IL-18 G137C variant may be a marker for ovarian cancer progression or metastasis.  相似文献   
180.
PURPOSE: We determined the maximum-tolerated dose (MTD) and the dose-limiting toxicities (DLT) of 17-allylamino-17-demethoxygeldanamycin (17-AAG) when infused on days 1, 8, and 15 of a 28-day cycle in advanced solid tumor patients. We also characterized the pharmacokinetics of 17-AAG, its effect on chaperone and client proteins, and whether cytochrome P450 (CYP) 3A5 and NAD(P)H:quinone oxidoreductase 1 (NQO1) polymorphisms affected 17-AAG disposition or toxicity. PATIENTS AND METHODS: An accelerated titration design was used. Biomarkers were measured in peripheral-blood mononuclear cells (PBMCs) at baseline and on days 1 and 15, and pharmacokinetic analysis was performed on day 1 of cycle 1. CYP3A5*3 and NQO1*2 genotypes were determined and correlated with pharmacokinetics and toxicity. RESULTS: Twenty-one patients received 52 courses at 11 dose levels. DLTs at 431 mg/m(2) were grade 3 bilirubin (n = 1), AST (n = 1), anemia (n = 1), nausea (n = 1), vomiting (n = 1), and myalgias (n = 1). No tumor responses were seen. 17-AAG consistently increased heat shock protein (Hsp) 70 levels in PBMCs. At the MTD, the clearance and half-life (t(1/2)) of 17-AAG were 11.6 L/h/m(2) and 4.15 hours, respectively; whereas the active metabolite 17-aminogeldanamycin had a t(1/2) of 7.63 hours. The CYP3A5*3 and NQO1*2 polymorphisms were not associated with 17-AAG toxicity. The CYP3A5*3 polymorphism was associated with higher 17-AAG clearance. CONCLUSION: The MTD of weekly 17-AAG is 308 mg/m(2). 17-AAG induced Hsp70 in PBMCs, indicating that Hsp90 has been affected. Further evaluation of 17-AAG is ongoing using a twice-weekly regimen, and this schedule of 17-AAG is being tested in combination with chemotherapy.  相似文献   
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