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81.
背景与目的:阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者罹患心血管疾病的危险性增加。内皮细胞损伤被认为是动脉硬化的始动机制之一。本研究观察了OSAHS患者循环中凋亡的内皮细胞与血管收缩功能异常的关系。方法:研究对象包括14例确诊OSAHS患者和10例健康对照。在基线以及持续气道内正压(CPAP)治疗8周后测定臂动脉血流介导扩张(反映内皮依赖臂动脉扩张的指标)。采用流式细胞术测量循环中凋亡的内皮细胞。结果: 相似文献
82.
Rocio A. Lopez Stuti Schoetz Kathryn DeAngelis David O''Neill Arthur Bank 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(2):602-607
We have previously reported the structure of a chromatin remodeling complex (PYR complex) with Ikaros as its DNA binding subunit that is specifically present in adult murine and human hematopoietic cells. We now show that homozygous Ikaros "knockout" (null) mice lack the PYR complex, demonstrating the requirement for Ikaros in the formation of the complex on DNA. Heterozygous Ikaros null mice have about half as much PYR complex, indicating a dosage effect for both Ikaros and PYR complex. We also show that Ikaros null mice have multiple hematopoietic cell defects including anemia and megakaryocytic abnormalities, in addition to previously reported lymphoid and stem cell defects. The null mice also have a delay in murine embryonic to adult beta-globin switching and a delay in human gamma to beta switching, consistent with a previously suggested role for PYR complex in this process. Lastly, cDNA array analyses indicate that several hematopoietic cell-specific genes in all blood lineages are either up- or down-regulated in 14-day embryos from Ikaros null as compared with wild-type mice. These results indicate that Ikaros and PYR complex function together in vivo at many adult hematopoietic cell-specific genes and at intergenic sites, affecting their expression and leading to pleiotropic hematopoietic defects. 相似文献
83.
Immunofluorscence studies have shown that injection of lymphocytes from either the intestinal lamina propria (LP) or from the Peyer's patches (PP) into irradiated (1000-1250 rad) allogeneic rabbits leads to the differentiation and proliferation of IgA containing cells in the spleen, mesenteric lymph node (MLN) and intestine by day 6 and to a lesser extent by day 4. In contrast, few IgA containing cells were seen in irradiated animals not given lymphocytes or given popliteal lymph node cells. Transfer of PP lymphocytes resulted in statistically greater numbers of IgA containing cells in the recipient MLN or spleen than did transfer of LP lymphocytes. In the PP of recipient rabbits given either LP or PP lymphocytes, intercellular IgA was abundant and more IgA containing cells were seen near the PP than in sites distant from PP. These results show that IgA precursor cells are present in the intestinal LP as well as in the PP. The nature and distribution of the IgA precursor and the characteristics of the IgA repopulation are discussed. 相似文献
84.
BACKGROUND: The systemic hypotension during human sepsis has been ascribed to increased production of nitric oxide (NO). Therefore, inhibitors of NO synthesis have been used in the treatment of hypotension in patients with septic shock. In addition, NO production may inhibit the synthesis and vasoconstrictor effects of endothelin-1 (ET-1). In this study, we tested whether ET-1 contributed to the vasopressor action of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in patients with severe septic shock. METHODS AND RESULTS: Compared with healthy volunteers, patients with septic shock had increased plasma levels of nitrite/nitrate (37+/-5 [SEM] versus 12+/-5 mmol/L, P<0.01), the stable end products of NO metabolism, and ET-1 (45+/-7 versus 3+/-2 pg/mL, P<0.001). Plasma ET-1 concentration was not related to plasma nitrite/nitrate concentration or blood pressure. Continuous infusion of L-NAME (1 mg. kg-1. h-1 IV) for 12 hours increased mean arterial pressure by 43+/-5% and systemic vascular resistance by 64+/-10% (both P<0.01). The increase in blood pressure and systemic vascular resistance correlated positively with the level of ET-1 (both P<0. 005) but not with plasma nitrite/nitrate level. L-NAME infusion did not result in significant changes in the plasma concentrations of ET-1 or nitrite/nitrate. CONCLUSIONS: NO and ET-1 may both play a role in the cardiovascular derangements of human sepsis. Although L-NAME does not increase ET-1 concentration in patients with septic shock, the vasopressor response induced by L-NAME depends on the plasma level of ET-1. These findings may indicate that inhibitors of NO synthesis unmask a tonic pressor response of ET-1 in human septic shock. 相似文献
85.
B F O''Donnell C M O''Neill D M Francis N Niimi R M Barr R J Barlow A Kobza Black K I Welsh & M W Greaves 《The British journal of dermatology》1999,140(5):853-858
The major histocompatibility complex (MHC) acts as a marker for self during T-cell ontogeny and is associated with the pathogenesis of many autoimmune diseases. Recent investigations have shown about 30% of patients with chronic idiopathic urticaria (CIU) have IgG autoantibodies against the high-affinity IgE receptor, FcepsilonRI, or IgE. A link between MHC class II alleles and CIU has not been reported previously. DNA was extracted from blood of 100 Caucasian patients with CIU, and the MHC class II type determined using the polymerase chain reaction with sequence-specific primers, testing for DRB and DQB1 alleles. The frequency of alleles in CIU patients was compared with that found in 603 controls. Further human leucocyte antigen (HLA) typing on patient subsets, classified by the patients' responses to intradermal injection of autologous serum and their serum-induced histamine release from basophil leucocytes of healthy donors, was undertaken. HLA DRB1*04 (DR4) and its associated allele, DQB1*0302 (DQ8), are raised in CIU patients compared with a control population (P = 2 x 10-5 and P = 2 x 10-4, respectively). HLA DRB1*15 (DR15) and its associated allele, DQB1*06 (DQ6), are significantly less frequently associated with CIU. The HLA DRB1*04 association is particularly strong (corrected P = 3.6 x 10-6) for patients whose serum has in vivo and in vitro histamine-releasing activity. HLA class II typing is consistent with the concept that CIU is a heterogeneous disease, and supports an autoimmune pathogenesis in a subset of patients. 相似文献
86.
A. R. Pachner E. Delaney W. F. Zhang T. O''Neill E. Major A. B. Frey E. Davidson 《Clinical immunology (Orlando, Fla.)》1999,91(3):310-313
In an effort to develop an effective and safe vaccine for lyme disease, rhesus macaques were injected with a multiantigenic preparation of Borrelia burgdorferi, strain N40. One month later animals were boosted before intradermal challenge with infectious B. burgdorferi. Challenges were performed at 1 and again at 5 months after the booster vaccination. Vaccinated and control nonvaccinated animals were monitored for development of systemic infection by measurement of serum anti-spirochetal antibodies by ELISA and Western blotting, and neurological involvement was monitored by testing of cerebrospinal fluid (CSF) and PCR analysis of central nervous system (CNS) tissue obtained at necropsy. Two control nonhuman primates (NHPs), given saline injections instead of vaccine and then challenged with B. burgdorferi, developed CSF pleocytosis, PCR positivity of the brain, and high levels of specific anti-B. burgdorferi antibody in the serum and CSF. Necropsy studies revealed widespread invasion of the CNS of one of these animals by the spirochete. In contrast, none of the four vaccinated animals developed evidence of invasion of the CNS after either of two challenge inoculations with infectious B. burgdorferi. In addition to resisting infection, no vaccinated animal demonstrated any untoward consequence of vaccination. These data demonstrate that a multiantigenic vaccine is effective in preventing systemic infection and lyme neuroboreliosis in NHPs and suggest that a successful vaccine could be developed in humans which would prevent lyme disease. 相似文献
87.
Jessica L. O''Neill Pharm.D. Caroline A. Gaither Ph.D. F.A.Ph.A. 《Research in social & administrative pharmacy》2007,3(4):438-463
BACKGROUND: Pharmacy employers are being challenged to recruit and retain qualified employees. OBJECTIVES: Our study hypothesized that pharmacists who practice pharmaceutical care have an attractive construed external image (how employees think outsiders view their organization), which strengthens their organizational identification (perceptions of oneness with or belongingness to the organization) and decreases job turnover intention (thoughts of quitting/searching for another job). METHODS: A 7-page questionnaire was mailed to the homes of a random sample of 759 licensed pharmacists practicing in the United States. Participants had the option of returning the completed survey via postal mail or a Web site. The study variables were measured with previously validated scales. Structural equation modeling with latent variables evaluated the hypothesized relationships. Several demographic variables were included. RESULTS: Responses were received from 252 subjects (33%); 121 were community pharmacists. As hypothesized, organizational identification and job turnover intention were significantly related (B=-0.24) as well as construed external image and organizational identification (B=0.41). The practice of pharmaceutical care and construed external image were not significantly correlated (B=0.10). Although not hypothesized, construed external image was directly related to job turnover intention (B=-0.25). The effects of the practice of pharmaceutical care on job turnover intention were mediated through organizational identification. Position had significant effects. CONCLUSIONS: One additional benefit to the practice of pharmaceutical care may be strengthened organizational identification. Pharmacists' perception of the image of their employer may increase organizational identification and decrease job turnover intention. An understanding of the organizational identification of pharmacists would be useful in decreasing job turnover intention. Given the current demand for pharmacists, this is a worthwhile endeavor. Future research should focus on other predictors of construed external image and ways to enhance organizational identification. Encouraging the practice of pharmaceutical care may be 1 such way. 相似文献
88.
89.
90.
Naoumova O''Neill Dunn Neuwirth Taylor Axelson & Thompson 《European journal of clinical investigation》1999,29(5):404-412
BACKGROUND: Atorvastatin is a potent inhibitor of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, but its effect on bile acid synthesis is unknown. The objectives of the study were to determine the effect of atorvastatin on bile acid synthesis in patients in whom this process had not been or had been previously up-regulated by pharmacological or surgical means. MATERIALS AND METHODS: Four patients with heterozygous familial hypercholesterolaemia (FH) and partial ileal bypass (PIB) and 19 FH heterozygotes without PIB were treated with placebo, atorvastatin 10 mg and atorvastatin 40 mg daily, each regimen for 4 weeks. The non-PIB group was subsequently treated with bile acid (BA) sequestrant 8-16 g daily followed by co-administration of atorvastatin 10 mg, each for 4 weeks. Plasma 7 alpha-hydroxy-4-cholesten-3-one (7 alpha-HCO), a well-validated marker of BA synthesis was measured using high-performance liquid chromatography with UV detection. RESULTS: The plasma 7 alpha-HCO concentration was tenfold higher with placebo in the PIB than in the non-PIB group (418.5 ng mL-1 vs. 39.6 ng mL-1 p = 0.0001). Levels decreased in PIB patients treated with atorvastatin 10 mg and 40 mg daily (350.1 ng mL-1 and 174.0 ng mL-1, P = 0.007 respectively) but did not change significantly in the non-PIB group (44.7 ng mL-1 and 28.3 ng mL-1 respectively). Administration of BA sequestrant to non-PIB patients increased 7 alpha-HCO to 197.4 ng mL-1; this decreased to 106.0 ng mL-1 during co-administration of atorvastatin 10 mg daily (P = 0.0001). CONCLUSION: Atorvastatin decreases the rate of BA synthesis only if the latter is up-regulated by PIB or BA sequestrants, presumably by limiting the supply of newly synthesized free cholesterol. 相似文献