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91.
George J; Levy Y; Kallenberg CG; Shoenfeld Y 《QJM : monthly journal of the Association of Physicians》1997,90(5):367-373
The association of infections and autoimmune disease has been noted by
various authors. Several mechanisms have been proposed to explain this,
with no current consensus. Wegener's granulomatosis (WG) is an autoimmune
disease involving predominantly the pulmonary and renal systems, and is
associated with a distinct autoantibody-the anti neutrophil cytoplasmic
antibody (ANCA). Although no solid evidence implicates infections in the
emergence of WG, direct and circumstantial data suggest this relation. We
review this evidence and discuss possible underlying mechanisms. We
emphasize the relationship between infections and ANCA, and their role in
the maintenance of the 'on- going' inflammatory response.
相似文献
92.
93.
Persistence of Staphylococcus aureus as detected by polymerase chain reaction in the synovial fluid of a patient with septic arthritis 总被引:1,自引:0,他引:1
Canvin JM; Goutcher SC; Hagig M; Gemmell CG; Sturrock RD 《Rheumatology (Oxford, England)》1997,36(2):203-206
Septic arthritis commonly occurs in the rheumatoid arthritis population.
The diagnosis is frequently delayed and the associated mortality is high.
In this brief report, we present a patient with rheumatoid arthritis and
prosthetic knee joints who developed septic arthritis and had persisting
evidence of Staphylococcus aureus DNA in synovial fluid, from his knees,
which was detected by polymerase chain reaction (PCR) and a gene probe.
This was detected until 10 weeks of therapy despite adequate antibiotic
treatment and a sterile synovial fluid. In the future, it may be found that
PCR of the synovial fluid will be a valuable investigation for the
diagnosis and management of septic arthritis.
相似文献
94.
Leucocyte membrane expression of proteinase 3 correlates with disease activity in patients with Wegener's granulomatosis 总被引:3,自引:0,他引:3
Wegener's granulomatosis (WG) is an inflammatory disorder characterized by
granulomatous inflammation and vasculitis, and is strongly associated with
antineutrophil cytoplasmic antibodies (ANCA). ANCA in patients with WG are
directed against proteinase 3 (Pr3) in most of the cases. In vitro, upon
neutrophil priming, ANCA antigens are expressed on the cell surface,
thereby becoming available for interaction with ANCA. Subsequently, these
neutrophils become activated. Since ANCA can only interact with leucocytes
when the ANCA antigens are present on the cell surface, we questioned
whether Pr3 is already expressed on the membranes of circulating
granulocytes and monocytes of patients with WG, and whether Pr3 expression
is related to disease activity, so explaining the systemic nature and
severity of the disease. The expression of Pr3, and other ANCA antigens,
i.e. myeloperoxidase (MPO) and human leucocyte elastase (HLE), was analysed
on circulating granulocytes and monocytes by flow cytometry, using a
non-activating whole-blood method. Disease activity was quantitated using
the Birmingham Vasculitis Activity Score (BVAS). Seventeen patients with
active WG and anti-Pr3 antibodies were included in this study. Nine of
these patients were also analysed at the time of remission. Twelve patients
with sepsis served as positive controls, and 10 healthy volunteers as
negative controls for granulocyte/monocyte activation. Pr3 expression on
neutrophils was increased in patients with active WG compared to patients
with quiescent disease and healthy controls. On monocytes, no differences
in Pr3 expression were found between those groups. Furthermore, the
expression of MPO and HLE did not differ between patient groups and healthy
controls. Upon follow-up, the expression of Pr3 on neutrophils from
patients with active WG decreased when patients went into remission. Pr3
expression on neutrophils correlated with the BVAS score (r = 0.40, P <
0.05). In conclusion, circulating neutrophils from patients with active WG
have increased expression of Pr3. In addition, the expression of Pr3
correlates with disease activity, suggesting that the availability of Pr3
for interaction with ANCA plays a central role in the disease process.
相似文献
95.
Sang‐Ha Baik PhD Mitchell Fane BSc Joon Hyung Park MSc Yi‐Lin Cheng PhD David Yang‐Wei Fann BSc Ui Jeong Yun MSc Yuri Choi MSc Jong‐Sung Park PhD Bing Han Chai BSc Jin Su Park MSc Seung Hyun Back MSc Jae In Jeong MSc Ye Jin Jang MSc Gahee Bahn MSc Joo‐Yong Lee PhD Yu‐I Li MD PhD Christopher G. Sobey PhD Takafumi Uchida PhD Jae Hyung Park PhD Hong Tae Kim PhD Sung‐Chun Tang MD PhD Thiruma V. Arumugam PhD Dong‐Gyu Jo PhD 《Annals of neurology》2015,77(3):504-516
96.
A 21-year-old woman presented with acute onset of upper abdominal pain. A diagnosis of Peutz-Jeghers syndrome (PJS) was made based on the clinical picture of perioral pigmentation with imaging findings of transient jejunojejunal intussusceptions and small bowel polyps, and confirmed by characteristic histopathological appearances of Peutz-Jeghers polyps. PJS is a rare hereditary condition characterised by unique hamartomatous polyps, perioral mucocutaneous pigmentations, and increased susceptibility to gastrointestinal and extraintestinal neoplasms. Patients usually present with recurrent abdominal pain due to intussusception caused by polyps. Other modes of presentations include rectal bleeding and melaena. We describe the imaging findings of PJS and provide a brief review of bowel polyposis syndromes. The latter are relatively rare disorders characterised by multiple polyps in the large or small intestine, with associated risk of malignancies and other extraintestinal manifestations. Awareness of the manifestations and early diagnosis of these syndromes is crucial to prevent further complications. 相似文献
97.
The purine metabolic enzymes adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) are important in lymphocyte differentiation, and genetic deficiencies of either enzyme have been associated with hereditary immunodeficiency states. Both ADA and PNP activity were measured in null cell-enriched and T cell-enriched peripheral blood lymphocytes from 16 patients with the acquired immune deficiency syndrome (AIDS), seven patients with the AIDS-related symptom complex (ARC), and seven asymptomatic homosexuals. ADA activity in nmol/10(6) lymphocytes/h was significantly elevated in null lymphocytes from AIDS (161 +/- 12) as compared with 23 healthy heterosexual controls (127 +/- 8;P less than .025). PNP activity was also significantly increased in null lymphocytes from AIDS patients (96 +/- 10;P less than .005) as well as those from ARC patients (84 +/- 11:P less than .025) relative to controls (61 +/- 5). No significant differences in enzyme activity were noted in T cell-enriched cells in any group. Along with elevated enzyme activity, AIDS patients had small yet significant increases in the percentages of HLA-DR (P less than .025), terminal deoxynucleotidyl transferase (TdT) (P less than .0001), and peanut agglutinin receptor (P less than .0001) positive lymphocytes in the null fraction compared with controls. TdT-positive cells appeared morphologically as large lymphoblasts with irregular nuclei. The data imply that the cellular immune deficiency in AIDS is not a result of deficiencies in lymphocyte ADA or PNP activity, but is more likely associated with an increase in an immature and/or activated lymphocyte subset. 相似文献
98.
Miller AA De Silva TM Jackman KA Sobey CG 《Clinical and experimental pharmacology & physiology》2007,34(10):1037-1043
1. It is well documented that the incidence and severity of several vascular diseases, such as hypertension, atherosclerosis and stroke, are lower in premenopausal women than men of similar age and post-menopausal women. The mechanisms responsible for gender differences in the incidence and severity of vascular disease are not well understood. However, emerging evidence suggests that sex hormone-dependent differences in vascular oxidative stress may play an important role. The aim of the present brief review is to provide an insight into the effect of gender and sex hormones on vascular oxidative stress. 2. When production of reactive oxygen species (ROS) is enhanced and/or their metabolism by anti-oxidant enzymes is impaired, a condition known as 'oxidative stress' can develop. Oxidative stress is believed to play an important role in both the initiation and progression of a variety of vascular diseases, including hypertension and atherosclerosis. NADPH oxidases are believed to be the major source of vascular ROS. Moreover, excessive production of ROS by NADPH oxidases has been linked to the development of vascular oxidative stress. 3. Increasing evidence suggests that levels of vascular ROS may be lower in women than men during health and disease. Indeed, the activity and expression of vascular NADPH oxidase is lower in female versus male animals under healthy, hypertensive and atherosclerotic conditions. 4. Gonadal sex hormones may play an important role in the regulation of vascular oxidative stress. For example, oestrogens, which are present in highest levels in premenopausal women, have been reported to lower vascular oxidative stress by modulating the expression and function of NADPH oxidases, as well as anti-oxidant enzymes. 5. Further studies are needed to clarify whether lower vascular oxidative stress in women in fact protects against the initiation and development of vascular disease and to further define the roles of gonadal sex hormones in such an effect. Knowledge gained from these studies may potentially lead to advances in the clinical diagnosis and treatment of vascular disease in both genders. 相似文献
99.
Hitesh Peshavariya Gregory J. Dusting Fan Jiang Lesley R. Halmos Christopher G. Sobey Grant R. Drummond Stavros Selemidis 《Naunyn-Schmiedeberg's archives of pharmacology》2009,380(2):193-204
Proliferation and apoptosis of endothelial cells are crucial angiogenic processes that contribute to carcinogenesis and tumor
progression. Emerging evidence implicates the regulation of proliferation and apoptosis by reactive oxygen species (ROS) such
as superoxide and hydrogen peroxide (H2O2). In the present study, we investigated the roles of the ROS-generating Nox4- and Nox2-containing reduced nicotinamide adenine
dinucleotide phosphate (NADPH) oxidases in proliferation of human endothelial cells by examining the impact of these enzyme
systems on (1) specific proliferative and tumorigenic kinases, extracellular regulated kinase1/2 (ERK1/2) and Akt, (2) cytoskeletal
organization, and (3) the mechanisms that influence cellular apoptosis. ROS production and the expression of NADPH oxidase
subunit Nox4, but not Nox2, were markedly higher in proliferating than in quiescent endothelial cells. Addition of the H2O2 scavenger catalase or downregulation of Nox4 protein with specific siRNA reduced ROS levels, cell proliferation, and ERK1/2
phosphorylation but had no effect on either cell morphology or caspase 3/7 activity. Although downregulation of Nox2 protein
with siRNA also reduced ROS production and cell proliferation, it caused an increase in caspase 3/7 activity, reduced Akt
phosphorylation, and caused cytoskeletal disorganization. Therefore, in endothelial cells, Nox4-derived H2O2 activates ERK1/2 to promote proliferation, whereas Nox2-containing NADPH oxidase maintains the cytoskeleton and prevents
apoptosis to support cell survival. Our study provides a new understanding of the molecular mechanisms that underpin endothelial
cell survival and a rationale for the combined suppression of Nox4- and Nox2-containing NADPH oxidases for unwanted angiogenesis
in cancer. 相似文献
100.