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41.
The Wnt pathway, epithelial-stromal interactions, and malignant progression in phyllodes tumours 总被引:3,自引:0,他引:3
Sawyer EJ Hanby AM Rowan AJ Gillett CE Thomas RE Poulsom R Lakhani SR Ellis IO Ellis P Tomlinson IP 《The Journal of pathology》2002,196(4):437-444
In a previous study of phyllodes tumours, it has been shown that both the stroma and the epithelium can exhibit distinct molecular changes, suggesting that both are part of the neoplastic process. In view of this finding, it was decided to study stromal-epithelial interactions in these tumours by examining the Wnt-APC-beta-catenin pathway. Beta-catenin and cyclin D1 immunohistochemistry was performed on 119 phyllodes tumours. Eighty-six (72%) showed stromal nuclear beta-catenin localization and in 57% the staining was moderate or strong; however, of the eight malignant tumours in the series, seven showed absent or weak nuclear staining (p<0.025). In no tumour was nuclear beta-catenin staining seen in the epithelial component. Moderate or strong stromal cyclin D1 staining correlated with nuclear stromal beta-catenin staining (p<0.05). Forty-five of the tumours, including two malignant lesions, were screened for beta-catenin exon 3 mutations using SSCP and sequencing, but none was found. Loss of heterozygosity (LOH) of the marker D5S346 was used to infer APC mutation, but only one (benign) tumour showed LOH. Wnt2 and Wnt5a mRNA was localized by in situ hybridization in 13 cases (three malignant) chosen to reflect the different beta-catenin staining patterns. There was an association between strong nuclear beta-catenin staining of stromal cells and epithelial Wnt5a expression (p<0.0015). These data suggest that stromal proliferation in benign phyllodes tumours relies on abnormalities in the Wnt pathway which result not from mutation, but from Wnt5a expression in the epithelium. In the progression to malignancy, the stromal proliferation appears to become independent of the Wnt pathway and, presumably, of the epithelial component of these tumours. 相似文献
42.
Lymphokine-activated killer (LAK) cells can be focused at sites of tumor growth by products of macrophage activation 总被引:1,自引:0,他引:1
R J Migliori S A Gruber M D Sawyer R Hoffman A Ochoa F H Bach R L Simmons 《Surgery》1987,102(2):155-162
Successful adoptive cancer immunotherapy presumably depends on the accumulation of tumoricidal leukocytes at the sites of tumor growth. Large numbers of lymphokine-activated killer (LAK) cells can be generated in vitro by growth in high concentrations of interleukin-2 (IL-2), but relatively few arrive at the tumor site after intravenous injection. We hypothesize that the delivery of LAK cells to tumor sites may be augmented by previously demonstrated lymphocyte-recruiting factors, including activated macrophage products such as interleukin-1 (IL-1) and tumor necrosis factor. 111Indium-labeled LAK cells were injected intravenously into syngeneic mice bearing the macrophage activator endotoxin (LPS) in one hind footpad, and saline solution was injected into the contralateral footpad. Significantly more activity was recovered from the LPS-bearing footpad at all times during a 96-hour period. Recombinant IL-1 also attracted more LAK cells after injection into tumor-free hind footpads. Furthermore, LAK cells preferentially homed to hind footpads that were bearing 3-day established sarcomas after intralesional injections of LPS, IL-1, or tumor necrosis factor when compared with contralateral tumor-bearing footpads injected with saline solution alone. In preliminary experiments, mice with hind-footpad tumors appeared to survive longer after combined systemic IL-2 and LAK therapy if intralesional LPS was administered. These studies demonstrate that macrophage activation factors that have been shown capable of attracting circulating normal lymphocytes can also effectively attract LAK cells from the circulation. By the stimulation of macrophages at the sites of tumor growth, more LAK cells can be attracted. It is hoped that by "focusing" the migration of LAK cells to tumors, LAK cells and IL-2 would effect tumor regression more efficiently and with less toxicity. 相似文献
43.
Gemma M. J. Taylor Katherine Sawyer David Kessler Marcus R. Munaf Paul Aveyard Alison Shaw 《Health expectations》2021,24(2):411
BackgroundTobacco smoking rates are significantly higher in people with common mental illness compared to those without. Smoking cessation treatment could be offered as part of usual outpatient psychological care, but currently is not.ObjectiveTo understand patient and health care professionals'' views about integrating smoking cessation treatment into outpatient psychological services for common mental illness.DesignQualitative in‐depth interviews, with thematic analysis.ParticipantsEleven Improving Access to Psychological Therapies (IAPT) psychological wellbeing practitioners (PWPs), six IAPT patients, and six stop smoking advisors were recruited from English smoking cessation, and IAPT services.ResultsPatients reported psychological benefits from smoking, and also described smoking as a form of self‐harm. Stop smoking advisors displayed therapeutic pessimism and stigmatizing attitudes towards helping people with mental illness to quit smoking. PWPs have positive attitudes towards smoking cessation treatment for people with common mental illness. PWPs and patients accept evidence that smoking tobacco may harm mental health, and quitting might benefit mental health. PWPs report expertise in helping people with common mental illness to make behavioural changes in the face of mood disturbances and low motivation. PWPs felt confident in offering smoking cessation treatments to patients, but suggested a caseload reduction may be required to deliver smoking cessation support in IAPT.ConclusionsIAPT appears to be a natural environment for smoking cessation treatment. PWPs may need additional training, and a caseload reduction. Integration of smoking cessation treatment into IAPT services should be tested in a pilot and feasibility study.Patient or public contributionService users and members of the public were involved in study design and interpretation of data. 相似文献
44.
45.
K L Wickens J Crane T J Kemp S J Lewis W J D'Souza G M Sawyer M L Stone S J Tohill J C Kennedy T M Slater N E Pearce 《Epidemiology (Cambridge, Mass.)》1999,10(6):699-705
We conducted a prevalence case-control study to investigate the relation between family composition, infection, and development of asthma at age 7-9 years. Potential cases (399) and controls (398) were selected from the Wellington, NZ, arm of the International Study of Asthma and Allergies in Childhood, a population-based prevalence study. Further screening questions restricted cases to children with a diagnosis of asthma and current medication use (N = 233) and restricted controls to children without a history of wheezing and no diagnosis of asthma (N = 241). After controlling for confounders (including infections, atopy, and socioeconomic status), family size was strongly related to asthma. Having no siblings [prevalence odds ratio (POR) = 2.51; 95% confidence interval (CI) = 1.05-6.01] or one sibling (POR = 1.86; 95% CI = 1.14-3.03) was associated with an increased risk of asthma compared with having more than one sibling. Parent-reported rubeola infection (and possibly other similar viral exanthems) was independently associated with a decreased risk of asthma (POR = 0.48; 95% CI = 0.27-0.83), but reported pertussis infection (POR = 1.57; 95% CI = 0.58-4.24) and day care attendance in the first year of life (POR = 1.81; 95% CI = 0.93-3.51) were not strongly associated with increased risks of asthma. 相似文献
46.
Pyle MA Jasinevicius TR Lalumandier JA Kohrs KJ Sawyer DR 《General dentistry》1999,47(5):500-3; quiz 504-5
The occurrence of retromolar foramina (RMF) was examined in a sample of dry skulls (African American n = 249; Causcasian n = 226) to consider the potential clinical impact. A prevalence rate of 7.8% of RMF was found. There were no statistical differences based on race or gender. The prevalence may contribute to the explanation of a portion of inferior alveolar nerve block failures and provide insight into potential implications of surgery in the posterior mandible. 相似文献
47.
A domestic swine model was developed to examine the interaction of chemical warfare agents with anesthetics and other drugs used during general anesthesia. Animals were fully instrumented, and clinically relevant physiological parameters were monitored throughout the experimental procedures. Exposure of animals under halothane anesthesia to the chemical warfare agent sulfur mustard (HD; 1 mg/kg intravenous) produced mild signs of systemic intoxication during the subsequent 5 hours. Induction doses of ketamine 1 hour after HD exposure resulted in periods of profound apnea, with continued respiratory distress for the next 2 hours. When animals were treated with HD 1 hour after the initiation of ketamine anesthesia, severe and persistent convulsion-like muscular activity was observed within 45 minutes of HD administration. This nonpurposeful activity was not ameliorated by diazepam but was dramatically reduced or eliminated by resumption of halothane anesthesia. Treatment of HD-intoxicated pigs with succinylcholine produced a prolonged apnea resulting in death. In these apparently mildly HD-intoxicated animals, the introduction of ketamine or succinylcholine can rapidly induce potentially life-threatening situations. 相似文献
48.
Fifty five teenage girls with cystic fibrosis and their mothers were interviewed to assess the provision of sexual health information. Parents were the most common source of information for adolescents. The cystic fibrosis doctor was identified as the key resource for parents. Yet few parents had spoken to their doctor about these issues, and 96% requested more information. This information was wanted before puberty by mothers, and from puberty onwards by girls. 相似文献
49.
Screening for complement deficiency in bacterial meningitis 总被引:1,自引:0,他引:1
T Ernst PJ Späth C Aebi UB Schaad MG Bianchetti 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(9):1009-1010
Seventy-seven children with bacterial meningitis were screened for complement deficiency. Both the classical and the alternate pathways were normal in 75 patients. Transiently reduced total haemolytic activity of the classical pathway was documented in a boy with meningococcal meningitis. Total haemolytic activity of both the classical and the alternate pathways were reduced in another patient with pneumococcal meningitis: individual complement components determination indicated predominant activation of the alternate pathway. 相似文献
50.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献