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991.
992.
993.
In this study DC numbers, phenotype and DC responses to the Toll-like receptor (TLR)-3 ligand, poly I:C, were examined in new-onset Type 1 diabetes (T1D) patients (ND) and in established T1D patients (ED). Absolute blood myeloid DC (MDC) and plasmacytoid DC (PDC) numbers were decreased in ND and ED patients compared to age-matched controls. The decrease in MDC and PDC counts was less evident in patients with a combination of T1D and coeliac disease (CD) or CD alone. The age-dependent decline in blood DC numbers, found in control children, was not evident in ND patients, such that 2-10 years old ND children had similar MDC and PDC numbers to 15-17 years old controls. In ED patients the t-score of MDC and PDC numbers related to the age of diagnosis but not to disease duration. Blood DC in T1D patients were not distinguished from those of controls by the levels of HLA-DR, CD40 and CD86 expression or the percentage of DC expressing cytokines, IL-12, IL-10, IL-6 and TNF-alpha, in responses to poly I:C. If low DC numbers are shown to contribute to the autoimmunity in T1D, interventions aimed to increase DC numbers may mitigate against beta-cell loss.  相似文献   
994.
Detection of human bocavirus in Canadian children in a 1-year study   总被引:8,自引:0,他引:8       下载免费PDF全文
Human bocavirus was detected by PCR in 65 (5.1%) of 1,265 respiratory specimens collected in 2002 and 2003 from the Stollery Children's Hospital from children <17 years of age. The spectrum of illness included upper respiratory infection, croup, bronchiolitis, and pneumonia with a prominence of cough and fever.  相似文献   
995.
OBJECTIVES: Individuals with HIV constitute the largest group using cannabinoids for medicinal reasons; yet, no studies have directly compared the tolerability and efficacy of smoked marijuana and oral dronabinol maintenance in HIV-positive marijuana smokers. This placebo-controlled within-subjects study evaluated marijuana and dronabinol across a range of behaviors: eating topography, mood, cognitive performance, physiologic measures, and sleep. METHODS: HIV-positive marijuana smokers (n = 10) completed 2 16-day inpatient phases. Each dronabinol (5 and 10 mg) and marijuana (2.0% and 3.9% Delta9-tetrahydrocannabinol [THC]) dose was administered 4 times daily for 4 days, but only 1 drug was active per day, thereby maintaining double-blind dosing. Four days of placebo washout separated each active cannabinoid condition. RESULTS: As compared with placebo, marijuana and dronabinol dose dependently increased daily caloric intake and body weight in HIV-positive marijuana smokers. All cannabinoid conditions produced significant intoxication, except for low-dose dronabinol (5 mg); the intoxication was rated positively (eg, "good drug effect") with little evidence of discomfort and no impairment of cognitive performance. Effects of marijuana and dronabinol were comparable, except that only marijuana (3.9% THC) improved ratings of sleep. CONCLUSIONS: These data suggest that for HIV-positive marijuana smokers, both dronabinol (at doses 8 times current recommendations) and marijuana were well tolerated and produced substantial and comparable increases in food intake.  相似文献   
996.
OBJECTIVES: In this paper we examine Chlamydia trachomatis testing in settings other than genitourinary medicine (GUM) clinics, focusing on the factors associated with chlamydial infection and with postal testing. METHODS: Analysis of tests collected from young people aged 13-25 years (n = 4475) between May 2001 and June 2004 via postal testing kits, at a local sexual health clinic, and at further education colleges in Lothian, Scotland. RESULTS: 84.8% of the testers were female and 15.2% were male. 84 men (12.3%, 95% CI 10.1-15.0) and 403 women (10.6%, 95% CI 9.7-11.6) tested positive. The odds of a positive result was nearly doubled for postal and clinic testers, relative to college testers; and increased by 70% for 16-19-year-olds, compared with 13-15-year-olds. Postal testing was the main source for men (80.2%) while 46.1% of women used postal and 48.1% used clinic testing. Postal testing was significantly associated with age, sex and National Health Service (NHS) board area, with odds increasing with age, and lower odds among females than males, and among Lothian residents than those outwith this NHS board area. CONCLUSIONS: Substantial chlamydial infection was apparent among the young people in this study and positivity rates were highest among postal and clinic testers and those in the 16-19-year age group. While postal kits were the main source for men, and should be used to target them, the combination of this approach with continuing screening programmes in clinic settings would be most effective at targeting those most at risk.  相似文献   
997.
The health care industry is slowly embracing the use of statistical process control (SPC) to monitor and study causes of variation in health care processes. While the statistics and principles underlying the use of SPC are relatively straightforward, there is a need to be cognizant of the perils that await the user who is not well versed in the key concepts of SPC. This article introduces the theory behind SPC methodology, describes successful tactics for educating users, and discusses the challenges associated with encouraging adoption of SPC among health care professionals. To illustrate these benefits and challenges, this article references the National Hospital Quality Measures, presents critical elements of SPC curricula, and draws examples from hospitals that have successfully embedded SPC into their overall approach to performance assessment and improvement.  相似文献   
998.
999.
Research was conducted in order to assess potential exposure to asbestos while harvesting firewood from amphibole-contaminated trees near Libby, MT, USA. Three firewood-harvesting simulations took place in the summer and fall of 2006 in the Kootenai Forest inside the US Environmental Protection Agency (EPA) restricted zone surrounding the former W.R. Grace vermiculite mine. Another simulation was conducted near Missoula, MT, USA, which served as the control. The work practices following each simulation were consistent throughout each trial. Personal breathing zone (PBZ) asbestos concentrations were measured by phase contrast microscopy (PCM) and transmission electron microscopy (TEM). Surface wipe samples of personal protective clothing were measured by TEM. The mean (n = 12) PBZ PCM sample time-weighted average (TWA) concentration was 0.29 fibers per milliliter, standard deviation (SD = 0.54). A substantial portion (more than five fibers per sample) of non-asbestos fibers (cellulose) was reported on all PBZ samples (excluding field blanks) when analyzed by TEM. The mean (n = 12) PBZ TEM sample TWA concentration for amphibole fibers <5-microm long was 0.15 fibers per milliliter (SD = 0.21) and the mean (n = 12) PBZ TEM concentration for amphibole fibers >5-microm long was 0.07 fibers per milliliter (SD = 0.08). Substantial amphibole fiber concentrations were revealed on Tyvek clothing wipe samples. The mean concentration (n = 12) was 29 826 fibers per square centimeter (SD = 37 555), with 91% (27 192 fibers per square centimeter) comprised fibers <5-microm long. There were no significant differences in PBZ and wipe sample concentrations among the tasks performed by four investigators. Each of these three simulations were consistent in demonstrating that amphibole fibers are released from tree reservoirs during firewood-harvesting activities in asbestos-contaminated areas and that the potential for exposure exists during such activities.  相似文献   
1000.
Splenomegaly was discovered by chance in a 9-year-old boy who had no further complaints. Apart from splenomegaly and mild thrombocytopenia, no other pathological condition was found in the first instance. Ultrasound revealed a spleen with a median length of 16.7 cm. Blood tests remained stable and a bone marrow biopsy showed no pathology either. Doppler ultrasound of the splenic vessels was normal; screening for a coagulation disorder was not performed. A wait-and-see policy was instituted. Later, the patient developed haematemesis because ofoesophageal varices. It turned out that he had portal hypertension caused by thrombosis of the portal vein. The underlying cause was a heterozygous protein-C deficiency. Treatment consisted of anticoagulant therapy and a mesocaval shunt procedure. Splenomegaly is an atypical clinical manifestation in childhood. Coagulation disorders should be considered in children with splenomegaly.  相似文献   
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