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31.
Two studies were conducted to consider the looking behavior of infants and toddlers with Williams syndrome (WS).In Study 1,the looking behavior of a 10-month-old girl with WS during play sessions with her mother and with a stranger was compared to that of 2 groups of infants who were developing normally (ND),1 matched for chronological age and the other for developmental age. The infant with WS spent more than twice as much time looking at her mother as the infants in either contrast group did. She also spent twice as much time looking at the stranger.In addition, during 78%of this time, her gaze at the stranger was coded as extremely intense. Looks of this intensity were virtually never made by the ND infants. In Study 2,the looking behavior of 31 individuals with WS ages 8 to 43 months during a genetics evaluation was compared to that of 319 control children in the same age range (242 with developmental delay due to causes other than WS).Twenty-three of the 25 participants with WS aged 33 months or younger demonstrated extended and intense looking at the geneticist. In contrast, none of the control participants looked extensively or intently at the geneticist. Findings are discussed in the context of previous research on arousal and focused attention during normal development and on temperament and personality of older children and adults with WS. It is argued that the unusual looking patterns evidenced by infants and toddlers with WS presage the unusual temperament and personality of older individuals with WS, and the possibility of a genetic basis for these behaviors is addressed.  相似文献   
32.
Spontaneous cytolytic activity of shark peripheral blood leukocytes is observed only during periods of decreased environmental temperature (< 23°C). The effector cell is adherent to glass and is phagocytic. Leukocytes tested during warmer periods (26–31°C) exhibit no spontaneous activity; however, glass-adherent cells isolated from those fish are cytotoxic in vitro, indicating that the effector cell is present at all temperatures. During warmer temperatures, nonadherent cells added to adherent cells were shown to inhibit spontaneous cytotoxicity. This inhibition requires viable cells in contact with the spontaneous cytotoxic population. Thus decreased environmental temperature correlated with spontaneous cytotoxicity, and appears to affect a regulatory cell that is glass nonadherent. In addition, the cytotoxic effector cell is more active at 23°C than 30°C in vitro. These data show that by the time of emergence of the nurse shark, a temperature-dependent mechanism had evolved for cellular regulation of at least one immune function, spontaneous cytotoxicity.  相似文献   
33.
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients.  相似文献   
34.
The specificities of two anti-neuraminidase monoclonal antibodies have been compared by their ability to fix complement. They were found to differ to some extent in their reactivity with a range of N2 influenza viruses. Thus, as in the case of anti-hemagglutinin antibodies, anti-neuraminidase monoclonal antibodies are able to detect subtle structural changes in the viral antigen. Although both monoclonal antibodies fixed complement with intact virus, neither one fixed complement when complexed with isolated neuraminidase “heads”.  相似文献   
35.
36.
The present study showed that incorporation of CpG adjuvant into plasmid DNA coding for NcGRA7 antigen resulted in a twofold increase in the level of protection against congenital transfer of Neospora caninum. The level of protection was considerably higher than that observed in pups born from dams immunized with nonrecombinant plasmid.  相似文献   
37.
Serological markers of hepatitis B virus (HBV) replication were assessed in a randomized, controlled trial of prednisone withdrawal followed by α -interferon in the treatment of chronic hepatitis B. HBV DNA levels in more than 700 serial serum samples from 41 patients were determined by a sensitive and quantitative solution hybridization assay. Results were compared with HBV DNA polymerase (DNAp) activity and hepatitis B e antigen (HBeAg) in 21 untreated controls and 20 treated patients. Among treated patients, the mean pretherapy HBV DNA values were higher in nonresponders than in responders. During prednisone treatment, DNA levels increased an average of 2.1-fold in responders and 1.4-fold in nonresponders. During the 2-week rest interval between prednisone and interferon, DNA values fell an average of 57% in responders. In contrast, the mean DNA values in nonresponders did not change during the same interval. This early distinction between responders and nonresponders was not apparent from DNAp or HBeAg results. During interferon treatment, HBV DNA became undetectable in responders and remained negative during a 1-year follow-up. DNA in nonresponders declined to 14% of baseline during interferon treatment but increased to pretherapy levels after treatment. DNAp values generally paralleled HBV DNA values, but DNAp activity showed more variability and lower sensitivity than did the hybridization assay results. HBeAg values varied independently of HBV DNA and DNAp with a much delayed decline in responders. These results indicate that HBV DNA, when measured quantitatively by a sensitive solution hybridization assay, is an early predictor of the effects of antiviral agents on replication.  相似文献   
38.
Breast cancer risk associated with ovulation-stimulating drugs   总被引:4,自引:0,他引:4  
BACKGROUND: Despite the recognized role of hormones in the aetiology of breast cancer, there has been little evaluation of hormonal preparations used to treat infertility. METHODS: A retrospective cohort study of 12,193 women evaluated for infertility between 1965 and 1988 at five clinical sites identified 292 in situ and invasive breast cancers in follow-up through 1999. Standardized incidence ratios (SIRs) compared breast cancer risks with those of the general population. Analyses within the cohort estimated rate ratios (RRs) associated with medications after adjustment for other breast cancer predictors. RESULTS: Infertile patients had a significantly higher breast cancer risk than the general population [SIR = 1.29, 95% confidence interval (CI) 1.1-1.4]. Analyses within the cohort showed adjusted RRs of 1.02 for clomiphene citrate and 1.07 for gonadotrophins, and no substantial relationships to dosage or cycles of use. Slight and non-significant elevations in risk were seen for both drugs after > or = 20 years of follow-up (RRs = 1.39 for clomiphene and 1.54 for gonadotrophins). However, the risk associated with clomiphene for invasive breast cancers was statistically significant (RR = 1.60, 95% CI 1.0-2.5). CONCLUSIONS: Although there was no overall increase in breast cancer risk associated with use of ovulation-stimulating drugs, long-term effects should continue to be monitored.  相似文献   
39.
Oxatomide is a very potent inhibitor of histamine release induced by anti-1gE and Timothy pollen extract in passively sensitized human lung fragments and that induced by anti-1gE from human leucocytes. Its spectrum of activity is different from sodium cromoglycate-like drugs.In high concentrations oxatomide, like other antihistamines and related structures, induced histamine release from both lung and leucocytes. However, oxatomide induced histamine release far more effectively from sensitized lung than non-sensitized lung.Inhibition of immunologically induced histamine release by oxatomide may play a part in its action as an anti-hay fever and, possibly, an anti-asthmatic drug.  相似文献   
40.
Objective: Previous work has shown that manic-depressive illness and alcohol abuse are linked. This study further explores the relationship of alcohol and drug abuse in bipolar I patients and unipolar depressives and a comparison group obtained through the acquaintance method. Method: Diagnosis was accomplished according to Research Diagnostic Criteria (RDC): controls=469; bipolars=277; unipolar depressives=678. Systematic data were gathered using the SADS on lifetime and current drug abuse and alcoholism. Both patients and comparison subjects were then followed prospectively for 10 years. First degree family members were interviewed using the RDC family history method. Results: The group of bipolar patients and the group of unipolar patients had higher rates of drug and alcohol abuse than the comparison group when primary and secondary affective disorder patients were combined. However, primary unipolar patients did not have higher rates of alcohol or drug abuse than the comparison group. In contrast, primary bipolar patients had higher rates of alcoholism, stimulant abuse, and ever having abused a drug than the primary unipolar group and the control group. In an evaluation of the bipolar patients, drug abusers were significantly younger at intake and had a significantly younger age of onset of bipolar disorder. There was a significant increase in family history of mania or schizoaffective mania in the drug-abusing bipolar patients as compared to the non-abusing bipolar patients. Limitation: As in all adult samples of patients with affective illness, the chronology of alcohol and substance problems vis-à-vis the onset of illness was determined retrospectively. Conclusions: (1) Alcoholism and drug abuse are more frequent in bipolar than unipolar patients. (2) The drug abuse of bipolar patients tends toward the abuse of stimulant drugs. (3) In a bipolar patient, familial diathesis for mania is significantly associated with the abuse of alcohol and drugs. (4) More provocatively, these findings suggest the hypothesis of a common familial-genetic diathesis for a subtype of bipolar I, alcohol and stimulant abuse. Clinical implications: The present analyses, coupled with two previous ones from the CDS, suggest that drug abuse may precipitate an earlier onset of bipolar I disorder in those who already have a familial predisposition for mania. Furthermore, in dually diagnosed patients with manic-depressive and alcohol/stimulant abuse history, mood stabilization of the bipolar disorder represents a rational approach to control concurrent alcohol and drug problems, and should be studied in systematic controlled trials.  相似文献   
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