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61.
Pooling of clinical specimens prior to testing for Chlamydia trachomatis by PCR is accurate and cost saving 下载免费PDF全文
Currie MJ McNiven M Yee T Schiemer U Bowden FJ 《Journal of clinical microbiology》2004,42(10):4866-4867
The accuracy and cost savings of pooling specimens prior to testing for Chlamydia trachomatis by PCR were evaluated with genital and urine specimens (n = 2,600). There was a 60% reduction in tests without significant loss of accuracy. The efficiency of pooling vaginal swabs is demonstrated for the first time. 相似文献
62.
Cohen JH Faughnan ME Letarte M Vandezande K Kennedy SJ Krahn MD 《American journal of medical genetics. Part A》2005,137(2):153-160
Endoglin (ENG) and ALK-1 mutations cause hereditary hemorrhagic telangiecstasia (HHT), an autosomal dominant disorder leading to vascular dysplasia in the form of mucocutaneous telangiectasia and visceral arteriovenous malformations (AVMs). We proposed to compare two alternative strategies for management of HHT: screening HHT families with molecular diagnostic tests followed by targeted clinical screening versus conventional clinical screening. A decision analytic model was constructed to compare screening strategies for a hypothetical HHT family. The family consists of 1 index case and 13 relatives. The clinical screening protocol in use at the Canadian HHT Center in Toronto was assumed to be the standard of care. Unit costs for clinical screening (in Canadian dollars) were obtained from the 2003 Ontario Health Insurance Schedule of Benefits. Genetic screening costs were estimated for quantitative multiplex PCR and sequencing of Endoglin (ENG) and ALK-1 genes, as performed at HHT Solutions, Toronto. The genetic screening strategy resulted in a net cost of $4,060 per individual versus $5,975 for the clinical screening strategy. The genetic screening strategy would save $1,915 per family member or $26,810 saved per family. Sensitivity analyses revealed that the genetic screening strategy was cost saving over all plausible ranges of input variables for all hypothetical families tested. We concluded that a genetic screening strategy with targeted clinical screening is more economically attractive than conventional clinical screening and results in a reduction in the number of clinical tests for family members who do not have HHT. 相似文献
63.
Regulation of CD23 in the chronic inflammatory response in asthma: a role for interferon-gamma and heat shock protein 70 in the TH2 environment. 总被引:2,自引:0,他引:2
Michelle S Harkins Pope L Moseley Gary K Iwamoto 《Annals of allergy, asthma & immunology》2003,91(6):567-574
BACKGROUND: Monocytic cells and alveolar macrophages (AMs) are activated in patients with asthma, producing inflammatory cytokines. This occurs despite a TH2 environment that consists of the cytokines interleukin (IL) 4, IL-10, and IL-13. The mechanism by which this occurs may involve cross-linking of the low-alphaffinity IgE receptor CD23. OBJECTIVE: To determine the effect of the TH2 environment with interferon-gamma (IFN-gamma) and heat shock protein 70 (HSP 70) on CD23 receptor expression and tumor necrosis factor alpha (TNF-alpha) production. METHODS: We examined the effect of IL-4 and IL-13 in culture with IFN-gamma and HSP 70 on CD23 expression in both THP-1 cells and AMs from healthy controls via flow cytometry. AMs from mild asthmatic patients and THP-1 cells were evaluated for TNF-alpha production after cross-linking CD23 with immune complexes. RESULTS: Asthmatic AMs stimulated with anti-IgE exhibited a 5.7- +/- 1.9-fold increase in TNF-alpha protein. AMs from healthy controls increased the geometric mean +/- SD of CD23 2.00- +/- 0.50-fold in IL-4 and 2.14- +/- 0.50-fold in IL-13. THP-1 cells cultured with IL-4 and IL-13 then stimulated with IFN-gamma or HSP 70 increased CD23 expression above baseline as follows: IL-4, 2.16- +/- 0.31-fold; IL-13, 2.66- +/- 0.43-fold; IFN-gamma, 2.03- +/- 0.34-fold; IL-4/IFN-gamma, 9.14- to 4.02-fold; IL-13/IFN-gamma, 11.51- +/- 5.51-fold; IL-4/HSP, 5.20- +/- 0.61-fold; and IL-13/HSP, 5.60- +/- 0.79-fold. Stimulating the CD23 receptor with immune complexes significantly increased TNF-alpha production by THP-1 cells stimulated with IFN-gamma, IL-4, IL-13, or a combination of these. CONCLUSIONS: Both IFN-gamma and HSP 70, in the TH2 environment, up-regulate CD23 expression and thus may play an important role in maintaining the chronic inflammatory state in asthma. 相似文献
64.
Biparental Phodopus campbelli and uniparental P. sungorus juvenile litters (2 males, 2 females) both consumed amniotic fluid and placenta during the birth of younger siblings. Three days later, P. campbelli juveniles were most responsive to a displaced younger sibling. Thus, P. campbelli are responsive to pups as juvenile alloparents and as new parents; however, at intervening ages, infanticidal attack (bite) was seen. At 5, 7, 9, 11, or 13 weeks of age, male and female P. campbelli were given a 5-min test with an unrelated, 3-day-old, anesthetized pup. Females attacked more often than males, yet pup-retrieval rates did not differ. Female aggression increased with age and was replaced by retrieval behavior 3 days after parturition. Male attack ceased after a birth, but parental behavior did not increase, remaining below the rate for new fathers tested with their own awake pup. Over repeated testing, behavior in one test did not predict behavior in another. Transitions from caregiving alloparent to infanticidal adult and back to parental care were clear in females, but less discrete with this stimulus paradigm in these highly paternal males. 相似文献
65.
Platner JH Bennett LM Millikan R Barker MD 《Environmental and molecular mutagenesis》2002,39(2-3):102-107
The National Breast Cancer Coalition (NBCC) is a grassroots organization that represents breast cancer advocates and is committed to eradicating breast cancer. NBCC defines a breast cancer advocate as someone who has been personally affected by the disease (e.g., a breast cancer survivor, family member, or friend), represents a constituency, and is motivated to join the fight against the disease. One of the organization's goals is to ensure that breast cancer advocates have a seat at the table when decisions are made about breast cancer research and policy. To accomplish this goal, NBCC educates advocates so that they can participate in and make meaningful contributions to legislative, scientific, and regulatory decision-making bodies. In addition to creating educational opportunities for advocates, NBCC has spearheaded several initiatives designed to directly increase the quality and quantity of breast cancer research. NBCC has also played a major role in making funding available to breast cancer researchers. Two of NBCC's most notable programs include Project LEAD, an intensive science-training course for breast cancer advocates, and the Environmental Initiative, a collection of activities designed to improve research into the relationship between breast cancer and the environment. Breast cancer advocates trained by NBCC have partnered with the scientific community and individual scientists to improve the peer review, design, and implementation of breast cancer research. 相似文献
66.
D. Décimo Odile Boespflug M. Meunier-Rotival Michelle Hadchouel M. Tardieu 《Archives of virology》1993,130(3-4):269-277
Summary To study the host-dependent genetic variations in murine hepatitis virus type 3 (MHV 3) induced diseases, we localized the sites of MHV 3 (Mill Hill strain) expression within liver and brain by immunohistochemistry or hybridization in situ. Two strains of mice were studied: BALB/c mice, which develop an acute and lethal hepatitis and C3H mice which develop a chronic brain infection. In BALB/c mice, viral RNA and antigens appeared during the first 24 h post infection (p.i.) in liver, whereas viral RNA was barely detectable in brain, up until death at day 3 p.i. In C3H mice, viral RNA and antigens were detected simultaneously in liver and brain only at day 2 p.i. In brain, the virus was detected in meningeal and ependymal cells and in perivascular cortical areas (days 5 and 7 p.i.). After day 49, the virus was no longer detected in brain parenchyma, but persisted in meningeal cells. Two host-dependent genetic differences in viral processing were observed in the liver: (1) the virus was first detected in Kupffer cells in BALB/c mice and mostly in hepatocytes in C3H mice; (2) in BALB/c mice, the 180 kDa S viral glycoprotein appeared more frequently cleaved in 90 kDa form than in C3H mice. 相似文献
67.
A fastidious gram-negative bacterium was isolated from the blood of a 37-year-old man who had insidious endocarditis with a sudden rupture of a cerebral aneurysm. Characterization of the organism through phylogenetic and phenotypic analyses revealed a novel species of Cardiobacterium, for which the name Cardiobacterium valvarum sp. nov. is proposed. C. valvarum will supplement the current sole species Cardiobacterium hominis, a known cause of endocarditis. Surgeries and antibiotic treatment cured the patient's infection and associated complications. During cardiac surgery, a congenital bicuspid aortic valve was found to be the predisposing factor for his endocarditis. 相似文献
68.
Poulos LM O'Meara TJ Hamilton RG Tovey ER 《The Journal of allergy and clinical immunology》2002,109(4):701-706
BACKGROUND: IgE-mediated responses to natural rubber latex allergens have become a major health problem among recognized risk groups. OBJECTIVE: The purpose of this investigation was to measure the amounts of Hevea brasiliensis latex allergen (Hev b 1) inhaled and deposited on surfaces when latex or vinyl gloves were worn and compare the results with the conventional measures (breathing zone samplers) of occupational exposure. METHODS: Hev b 1 exposure was measured by nasal sampling and breathing zone sampling. Latex allergen exposure was generated by having each subject don a pair of powdered latex examination gloves and continuing his or her normal daily activity for 30 minutes. By means of adhesive tape, surface dust samples were collected from the surfaces of gloves, the subject's hands, and work areas. Sampling was performed with subjects wearing no gloves, subjects wearing powdered vinyl gloves, subjects wearing powdered latex gloves, and nearby colleagues wearing latex gloves. All samples were assayed through use of the HALOgen assay (Inhalix, Sydney, Australia) with a Hev b 1-specific mAb. Particles transporting latex allergen were identified by a surrounding immunostain halo, and these were quantified and reported as total numbers of particles inhaled, airborne, or found on surface areas evaluated. RESULTS: Study subjects inhaled 26 times more allergen when powdered latex gloves were worn than under the "no glove" and powdered vinyl glove conditions. During the same period, Hev b 1 particle levels measured in the ambient air through use of the breathing zone sampler increased by 24-fold. The median numbers of particles carrying Hev b 1 allergen per square centimeter on the surface of the hands after the wearing of latex and vinyl gloves were 1964 and 5, respectively. Latex allergen was physically associated both with cornstarch granules and with larger dust particles having a darker, more irregular appearance. CONCLUSION: In a laboratory where gloves are worn for protection, the use of latex gloves resulted in a 26-fold increase in inhaled latex allergen over background levels measured while vinyl gloves were worn as controls. Low levels of latex exposure also occurred when vinyl gloves or no gloves were worn; the reasons for this are under investigation. 相似文献
69.
Molecular epidemiologic evaluation of endocarditis due to Oerskovia turbata and CDC group A-3 associated with contaminated homograft valves 下载免费PDF全文
McNeil MM Brown JM Carvalho ME Hollis DG Morey RE Reller LB 《Journal of clinical microbiology》2004,42(6):2495-2500
Oerskovia turbata is an unusual bacterial cause of endocarditis and septicemia in immunocompromised patients. In this study, we compared 12 isolates from a 1975 medical center cluster, 11 originally identified as O. turbata (four from the blood of a homograft aortic valve-associated endocarditis patient and seven from contaminated homograft valves) and one CDC group A-3 strain from the blood of a second endocarditis patient with fatal outcome, with eight control strains from unrelated locations. The control strains included type and reference strains of O. turbata, Cellulomonas hominis, and CDC group A-3. The four blood isolates from the first patient and six of the valve isolates shared identical biochemical, antimicrobial susceptibility, and BglI ribotype patterns that differed from the second patient's isolate and control strains. The blood isolate from the second patient and the remaining valve isolate shared a phenotypic and genotypic profile and were phenotypically identical to, but epidemiologically different from, the CDC group A-3 reference strain with the strain-specific enzyme. Also, these isolates differed from the type strain and the other reference strains of C. hominis and O. turbata. Our results indicate that the four blood isolates from the first patient and six of the homograft valve isolates represent a single clone of O. turbata associated with endocarditis. Additionally, our results indicate that the blood isolate from the second patient and one of the homograft valve isolates differ from O. turbata and C. hominis and represent a unique clone of CDC group A-3 associated with fatal endocarditis. 相似文献
70.
This work discusses the strengths, limitations and validity of a novel arterial spin labeling technique when used specifically to measure perfusion in limb skeletal muscle. The technique, flow-driven arterial water stimulation with elimination of tissue signal (FAWSETS), offers several advantages over existing arterial spin labeling techniques. The primary goal of this study was to determine the perfusion signal response to changes in net hind limb flow that were independently verifiable. The range of perfusate flow was relevant to skeletal muscle during mild to moderate exercise. Localized, single voxel measurements were acquired from a 5 mm-thick slice in the isolated perfused rat hind limb at variable net flow rates. The results show that the perfusion signal is linearly proportional to net hind limb flow with a correlation coefficient of 0.974 (p = 0.0013). FAWSETS is especially well suited for studies of skeletal muscle perfusion, where it eliminates the need to compensate for magnetization transfer and arterial transit time effects. A conceptual discussion of the basic principles underlying these advantages is presented. 相似文献