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101.
102.
PURPOSE: Impaired immune effector functions in the melanoma sentinel lymph node (SLN) may allow for early metastatic events. Local administration of PF-3512676 (formerly known as CpG 7909) has shown immunostimulatory effects of both dendritic cell and T-cell subsets in the melanoma SLN. Here, we set out to ascertain whether these PF-3512676-induced immunostimulatory effects translate into higher frequencies of melanoma-specific CD8(+) T cells. EXPERIMENTAL DESIGN: Twenty-four stage I to III melanoma patients were randomized to preoperative local administration of either PF-3512676 or saline. CD8(+) T cells from SLN and peripheral blood were tested for reactivity by IFN-gamma ELISPOT assay against several HLA-A1/A2/A3-restricted epitopes derived from various melanoma-associated antigens (MAA) in 21 of 24 enrolled patients. Frequencies of natural killer (NK) cells and frequencies and maturation state of dendritic cell subsets in the SLN were determined by flow cytometry. RESULTS: Melanoma-specific CD8(+) T-cell response rates against >1 MAA epitope in the SLN were 0 of 11 for the saline group versus 5 of 10 for the PF-3512676-administered group (P = 0.012). Of these 5 responding patients, 4 also had a measurable response to >1 MAA epitope in the blood. Increased frequencies in the SLN of both MAA-specific CD8(+) T cells and NK cells correlated to CpG-induced plasmacytoid dendritic cell maturation. CONCLUSIONS: These data show an increase in melanoma-specific CD8(+) T-cell frequencies as well as an increased effector NK cell rate after a single dose of PF-3512676 and thus support the utility of local PF-3512676 administration as adjuvant treatment in early-stage melanoma to try and halt metastatic spread.  相似文献   
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OBJECTIVE: This study was designed to determine whether a community sample of obese mothers with young children used different feeding styles compared with a matched sample of normal-weight mothers. Four aspects of feeding style were assessed: emotional feeding, instrumental feeding (using food as a reward), prompting/encouragement to eat, and control over eating. RESEARCH METHODS AND PROCEDURES: Participants were from 214 families with same-sex twins; 100 families in which both parents were overweight or obese and 114 in which both parents were normal weight or lean. RESULTS: We found that obese mothers were no more likely than normal-weight mothers to offer food to deal with emotional distress, use food as a form of reward, or encourage the child to eat more than was wanted. The obese and normal-weight mothers did differ on "control"; obese mothers reported significantly less control over their children's intake, and this was seen for both first-born and second-born twins. Twin analyses showed that these differences were not in response to children's genetic propensities, because monozygotic correlations were no greater than dizygotic correlations for maternal feeding style. DISCUSSION: These results suggest that the stereotype of the obese mother, who uses food in nonnutritive ways so that her child also becomes obese, is more likely to be myth than fact. However, the results raise the possibility that lack of control of food intake might contribute to the emergence of differences in weight.  相似文献   
105.
Incipient CADASIL   总被引:1,自引:0,他引:1  
BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in the NOTCH3 gene. Knowledge of disease expression in young adult NOTCH3 mutation carriers (MCs) is limited. OBJECTIVE: To characterize clinical, neuropsychological, and radiological status in NOTCH3 MCs younger than 35 years. DESIGN: Clinical characterization and blinded survey comparing MCs with non-MCs. SETTING: Referral center. PARTICIPANTS: Individuals younger than 35 years who were at a 50% risk of a NOTCH3 mutation, from our CADASIL database. Thirteen individuals, from 8 families, met the criteria. METHODS: Comprehensive clinical, genetic, neuropsychological, and radiological investigations. Magnetic resonance images were scored according to a standardized white matter hyperintensities rating scale. RESULTS: Six individuals, from 5 families, were MCs. Clinical symptoms consisted of migraine (with aura), stroke, and stroke-like episodes. We did not find evidence for psychiatric disturbances, functional disability, or cognitive dysfunction, compared with non-MCs. Radiologically, a characteristic magnetic resonance imaging lesion pattern emerged for all MCs. This comprised white matter hyperintensities in the anterior temporal lobes, the frontal lobes, and the periventricular frontal caps. CONCLUSIONS: Migraine (with aura) and stroke can present in NOTCH3 MCs younger than 35 years; however, more importantly, physical function and cognition are intact. Possible subtle cognitive dysfunction needs to be assessed in a larger study. White matter hyperintensities on magnetic resonance imaging are characteristic, and are consistently visualized from the age of 21 years and onward. Awareness of the clinical and radiological features of CADASIL in those younger than 35 years should increase early diagnosis and allow for customized counseling of young adults from families with CADASIL.  相似文献   
106.
OBJECTIVES: The aim of the present study was to describe the patient's perspective on the GP's care after violent events: which role is the GP assigned; and how is the care appreciated. Events studied were serious accidents, burglary, robbery, physical and sexual abuse, disasters and war. METHOD: A postal questionnaire was sent to a random sample of 2997 patients (> or =20 years) from the practice population of 32 GPs (67 500 patients). RESULTS: The response was 50%. Forty-two per cent of the respondents had experienced one or more events. Twenty-eight per cent of the victims desired some kind of professional help; more than half of them desired that care from their GP, three-quarters actually seeking it. Most frequently sought care was sympathy, "a number of good talks", and care for physical complaints. Overall, contentment with the GP's contribution was high; patients especially appreciate sympathy and support, as well as initiative on the GP's part in commencing and pursuing care. Of those who felt no need for professional help, 88% found that they could cope with the traumatic event well enough, with or without the help of family and friends. For those who did not seek help, although they did desire it, the main reasons were that they considered their problems insufficiently medical or felt that their GP lacked the time. In the case of physical and sexual abuse, feelings of guilt and issues of patient confidentiality played a role for some patients. CONCLUSIONS: The number of events experienced by our respondents is lower than in previous studies for burglary, robbery, physical and sexual abuse (adults and children); the occurrence of accidents is similar. The majority of the people who experience traumatic events cope with them well enough without professional help. For those seeking help, the GP plays an important role. Care could be improved as follows: the GP should make it clear to patients that he/she can play a role in caring for them in the aftermath of a traumatic event and stress the confidential nature of the consultation. On the whole, GPs should be more supportive and attentive when being consulted about this topic; also patients would like their doctors to be more active in raising the subject, as well as in initiating follow-up.  相似文献   
107.
The c-kit tyrosine kinase inhibitor STI571 for colorectal cancer therapy   总被引:8,自引:0,他引:8  
The c-kit tyrosine kinase inhibitor STI571 exhibits a substantial therapeutic activity in patients with chronic myeloid leukemia and gastrointestinal stromal tumors respectively associated with constitutive activation of the BCR-ABL and c-kit tyrosine kinases. Human colorectal tumors also express the c-kit proto-oncogene. The present study focuses on the anticancer activity of STI571 in human colorectal tumor cells in vitro and in vivo. The c-kit receptor was identified as a M(r) 145,000 immunoreactive band in human colon cancer cells HT29, HCT8/S11, and HCT116. Cellular invasion induced by 10 ng/ml stem cell factor (EC(50) = 3 ng/ml) in HT29 cells was blocked by 1 micro M STI571 (IC(50) = 56 nM) and pharmacological inhibitors of several oncogenic signaling pathways, namely, phosphatidylinositol 3-kinase (LY294002), Rho GTPases (Clostridium botulinum exoenzyme C3 transferase), and Rho-kinase (Y27632). STI571 inhibited HT29 cell proliferation (IC(50) = 6 micro M) and induced apoptosis in vitro. These cellular effects were associated with a decrease in tumor growth. We also demonstrated that stem cell factor is a proangiogenic factor in vivo and in vitro. These encouraging results warrant further preclinical investigations and clinical trials on the use of the c-kit inhibitor STI571 as a chemotherapeutic agent in colon cancer prevention and in treatment of advanced colorectal cancers associated with liver metastases.  相似文献   
108.
TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) induces apoptosis in a large variety of cancer cells but not in most normal human cells. This feature makes TRAIL, a potential antitumor agent. TRAIL can bind to four different receptors, two pro-apoptotic death receptors (DRs), DR4 and DR5, and two antiapoptotic decoy receptors (DcRs), DcR1 and DcR2. Normal cells express all four of the receptors. The increased TRAIL sensitivity of tumor cells has been postulated to result from the lack of DcR expression. We studied the tumor-specific down-regulation of the TRAIL receptors DcR1 and DcR2, as well as DR4 and DR5, in a group of pediatric tumor cell lines [nine neuroblastoma and three peripheral primitive neuro-ectodermal tumors (PNETs)] and three cell lines from adult tumors. Lack of expression of DcR1 and DcR2 was widespread (13 of the 15 cell lines and 10 of 15, respectively), both in the adult tumor cell lines and in the pediatric tumor lines. DR4 and DR5 were expressed in 8 of 15 and 12 of 15 cell lines, respectively. To understand the tumor-specific down-regulation of the TRAIL receptors, the promoter regions were studied for possible methylation changes of their CpG islands. All normal tissues were completely unmethylated, whereas in the tumor cell lines, we found frequent hypermethylation of the promoter. For DcR1 and DcR2, we found dense hypermethylation in 9 (69%) of 13 and 9 (90%) of 10 of nonexpressing cell lines, respectively. DR4 and DR5 were methylated in 5 (71%) of 7 and 2 (67%) of 3 nonexpressing cell lines, respectively. Treatment with the demethylating agent 5-aza-2'deoxycytidine resulted in partial demethylation and restored mRNA expression. In addition, we performed mutation analysis of the death domains of DR4 and DR5 by sequencing exon 9. Mutations were not present in any of the neuroblastoma or PNET cell lines. A panel of 28 fresh neuroblastoma tumor samples also lacked expression of DcR1 and DcR2 in 85 and 74% of cases, respectively. Hypermethylation was observed in 6 (21%) of 28 for DcR1 and 7 (25%) of 28 for DcR2. DR4 and DR5 were both expressed in 22 of 28 tumors, and no promoter methylation was observed. These data suggest that hypermethylation of the promoters of DcR1 and DcR2 is important in the down-regulation of expression in neuroblastoma and other tumor types.  相似文献   
109.
OBJECTIVE: To assess relationships between hypoglycaemic awareness and diabetes-related, psychosocial and demographic characteristics. METHOD: Ninety-eight type 1 diabetic patients completed questionnaires on somatic awareness (Somatic Awareness Questionnaire, SAQ), negative affectivity (Positive And Negative Affectivity Schedule, PANAS), symptom beliefs, bustle and variety of daily life. They then performed up to 70 measurements on a hand-held computer, during 4 to 6 weeks, at home. During every measurement, they rated the presence of 20 symptoms on a 0-6 scale, and estimated and measured their blood glucose level. The percentage of recognised hypoglycaemic episodes was calculated from these data, and used as a measure of hypoglycaemic awareness. RESULTS: Hypoglycaemic awareness was negatively associated with disease duration and antecedent hypoglycaemia, and positively associated with the use of an insulin pump instead of injections, variety in the daily life, somatic awareness, sensitivity of the symptom beliefs and female gender. However, only 17% of the variance in hypoglycaemic awareness was explained. CONCLUSIONS: Psychosocial variables contribute to hypoglycaemic awareness, to a moderate but statistically significant extent.  相似文献   
110.
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