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81.
A free exploration test was used to examine the effects of LSD on investigatory responding and locomotor activity in a novel environment. Rats were injected with 20–30 g/kg LSD or saline prior to being placed in a home cage. After 10 min, a door was opened permitting entry into a larger holeboard chamber where crossovers, rearings, hole pokes, and routes of locomotion were monitored. When administered either 10 or 30 min prior to testing, LSD reduced the time spent in the holeboard chamber only during the first half of a 1-h session, resulting in a corresponding reduction in all holeboard activity measures. In the subsequent 30 min, LSD-treated rats maintained a steady level of responding, in contrast to the continual derement exhibited by controls. Despite their initial avoidance of the holeboard, LSD-treated rats made consistently longer hole pokes into floor holes and showed a more diversified pattern of locomotion than did controls throughout the 1-h session. Most striking was the failure of LSD-treated rats to establish the stereotyped excursion routes, characteristic of controls, from the home cage to various parts of the holeboard. It is suggested that LSD potentiates both neophobic (avoidance) and investigatory responses to a novel environment by retarding the rate of behavioral habituation. 相似文献
82.
83.
Gelastic seizures are the hallmark of the epilepsy syndrome associated with hypothalamic hamartomas. Patients typically develop cognitive deterioration and refractory seizures. The authors describe three patients with small hypothalamic hamartomas without these features and thus identify a mild end to the clinical spectrum. All had the unusual symptom of "pressure to laugh," often without actual laughter. This symptom could be dismissed as psychogenic but should be recognized as a clue to the presence of this unusual lesion. 相似文献
84.
We evaluated retrospectively the treatment of 44 open femur fractures occurring between the lesser trochanter and the distal femoral physis in 43 children aged 16 years and younger. Fractures that involved the physis or that were a consequence of gunshot wounds were excluded. There were 25 grade I, 9 grade II, and 9 grade III fractures. The mean age at injury was 9.5 years. Ninety percent of the fractures were automobile related. More than 70% of the children had associated injuries. The average time to healing for all fractures in this study was 17 weeks. Our data indicate that there is a statistically significant increased time to heal with increasing age of the child (p = 0.04). Additionally, grade III fractures healed more slowly than grade I or II fractures (p = 0.0006). Fractures treated with external fixation took longer to unite than those treated with other methods (p = 0.05). The presence of complications increased the time to fracture union (p = 0.00001). Grade III injuries were the most difficult to manage; 50% of the fractures in this group developed osteomyelitis and 20% malunited. In contrast, none of the fractures in either the grade I or II groups developed deep infection. After aggressive debridement, grade I and grade II fractures may be stabilized with age-appropriate fixation methods. Grade III injuries should be managed with vigorous debridement and vigilance, as these injuries are prone to deep infection and malunion. The optimal method of skeletal stabilization in grade III fractures remains unresolved. 相似文献
85.
Intraobserver reproducibility and interobserver reliability of cervical spine measurements 总被引:2,自引:0,他引:2
Wellborn CC Sturm PF Hatch RS Bomze SR Jablonski K 《Journal of pediatric orthopedics》2000,20(1):66-70
Lateral flexion-extension radiographs of 72 patients with Down syndrome were used to assess the interobserver reliability and intraobserver reproducibility of the atlanto-dens interval, Wiesel-Rothman measurement, occiput atlas angle, and Power's ratio in flexion and extension. The radiographs were reviewed by three blinded observers on three different occasions with at least a 1-month interval between assessments. The intraclass correlation coefficient was used to measure the reproducibility of the measurements from a given observer and the reliability between different observers. With the exception of observer one, the atlanto-dens interval had a statistically significant intraobserver agreement compared with any of the other measurements (p < 0.05). The atlanto-dens interval and the Wiesel-Rothman measurements tended to have better correlation between observers, although there was only fair agreement. The agreement, however, was statistically significant (p < 0.05) compared with Power's ratio. The degree of intraobserver reproducibility and interobserver reliability may make it difficult to base treatment protocols on these measurements. 相似文献
86.
Ylva Y. Grams Soile Alaruikka Lisa Lashley Julia Caussin Lynne Whitehead Joke A. Bouwstra 《European journal of pharmaceutical sciences》2003,18(5):329-336
In skin and hair research drug targeting to the hair follicle is of great interest. Therefore the influence of permeant lipophilicity and vehicle composition on local accumulation has been examined using confocal laser scanning microscopy (CLSM). Formulations saturated with either Oregon Green® 488, Bodipy® FL C5 or Bodipy® 564/570 C5 were prepared. The dyes were applied in citric acid buffer, 8% (w/v) surfactants in citric acid buffer or 8% (w/v) surfactants/20% (w/v) propylene glycol in citric acid buffer. Flow-through diffusion experiments were performed with fresh human scalp skin, after which the skin was imaged using CLSM. Diffusion studies showed for Oregon Green® 488 (low lipophilicity) a higher flux when applied in citric acid buffer compared to surfactants. In contrast the fluxes of the more lipophilic dyes (Bodipy® FL C5 and Bodipy® 564/570 C5) are highest when applied in surfactants/propylene glycol. CLSM studies revealed that follicular accumulation increased with (i) a lipophilic dye and (ii) application of lipophilic dyes in surfactants–propylene glycol. Therefore we conclude that targeting to the hair follicle can be increased by the use of lipophilic drugs in combination with surfactant solutions and propylene glycol. 相似文献
87.
Haubrich C Frielingsdorf V Herzig S Schröder H Schwarting R Sturm V Voges J 《Brain research》2000,855(2):225-234
According to in vitro and in vivo studies, the direct application of N-type calcium channel blockers as for instance omega-conotoxin GVIA (omega-ctx) potently inhibits the release of neurotransmitters like dopamine. To find out whether this effect could be used for modulation of neurological functions, omega-ctx was used for continuous infusion into the functionally well characterized rat striatum. Over the 2-week time course of intrastriatal application, rats developed a decrease in spontaneous motor activity, spontaneous rotational asymmetry towards the side of application, and behavioral supersensitivity to apomorphine. After the end of infusion period, all functional deficits showed reversibility. The pattern of spontaneous neurological deficits - in particular supersensitivity to apomorphine - points to a substantial unilateral alteration of dopaminergic transmission due to omega-ctx, which is suggested also by an increase in dopamine receptor protein expression within the ipsilateral striatum. Time course and reversibility of neurological deficits caused by omega-ctx, as well as a lack of dopamine depletion contrast findings after selective destruction of dopaminergic neurons and support a functional modulation of dopaminergic transmission. The present study suggests that omega-ctx is an effective potent tool for the unilateral and reversible intracerebral modulation of neuronal circuits. Intracerebral application of omega-ctx could possibly open the way to therapeutic interventions. 相似文献
88.
Polymorphisms of interleukin (IL)-1α, IL-1β, IL-6, IL-10, and IL-18 and the risk of ovarian cancer 总被引:10,自引:0,他引:10
Abigail W. Bushley Robert Ferrell Katharine McDuffie Keith Y. Terada Michael E. Carney Pamela J. Thompson Lynne R. Wilkens Ko-Hui Tung Roberta B. Ness Marc T. Goodman 《Gynecologic oncology》2004,95(3):269-679
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
89.
Harry J Long Brian N Bundy Edward C Grendys Jo Ann Benda D Scott McMeekin Joel Sorosky David S Miller Lynne A Eaton James V Fiorica 《Journal of clinical oncology》2005,23(21):4626-4633
PURPOSE: On the basis of reported activity of methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) or topotecan plus cisplatin in advanced cervix cancer, we undertook a randomized trial comparing these combinations versus cisplatin alone, to determine whether survival is improved with either combination compared with cisplatin alone, and to compare toxicities and quality of life (QOL) among the regimens. PATIENTS AND METHODS: Eligible patients were randomly allocated to receive cisplatin 50 mg/m(2) every 3 weeks (CPT); cisplatin 50 mg/m(2) day 1 plus topotecan 0.75 mg/m(2) days 1 to 3 every 3 weeks (CT); or methotrexate 30 mg/m(2) days 1, 15, and 22, vinblastine 3 mg/m(2) days 2, 15, and 22, doxorubicin 30 mg/m(2) day 2, and cisplatin 70 mg/m(2) day 2 every 4 weeks (MVAC). Survival was the primary end point; response rate and progression-free survival (PFS) were secondary end points. QOL data are reported separately. RESULTS: The MVAC arm was closed by the Data Safety Monitoring Board after four treatment-related deaths occurred among 63 patients, and is not included in this analysis. Two hundred ninety-four patients enrolled onto the remaining regimens: 146 to CPT and 147 to CT. Grade 3 to 4 hematologic toxicity was more common with CT. Patients receiving CT had statistically superior outcomes to those receiving CPT, with median overall survival of 9.4 and 6.5 months (P = .017), median PFS of 4.6 and 2.9 months (P = .014), and response rates of 27% and 13%, respectively. CONCLUSION: This is the first randomized phase III trial to demonstrate a survival advantage for combination chemotherapy over cisplatin alone in advanced cervix cancer. 相似文献
90.