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41.
Goehler LE Gaykema RP Opitz N Reddaway R Badr N Lyte M 《Brain, behavior, and immunity》2005,19(4):334-344
Abundant evidence now supports the idea that multiple pathways or mechanisms underlie communication from the immune system to the brain. The presence of a variety of mechanisms suggests that they may each contribute something different to immunosensory signaling. For instance, brain mediated immune signal transduction is dependent upon the presence of circulating mediators whereas peripheral sensory nerves are more likely to be important early on in an infection, prior to elevation of circulating cytokines, or in local infections within the terminal fields of these nerves. To test the hypothesis that local infection in the gut activates vagal sensory neurons, we assessed expression of the neuronal activation marker c-Fos in neurons in the vagal sensory ganglia and in the primary sensory relay nucleus for the vagus, the nucleus of the solitary tract (nTS) in mice treated orally either with saline or live Campylobacter jejuni (C. jejuni). Male CF1 mice were inoculated orally with either C. jejuni or saline, and c-Fos expression in the vagal sensory neurons and brain 4-12 h later was assessed via immunohistochemistry. Oral inoculation with C. jejuni led to a significant increase in c-Fos expression in neurons bilaterally in the vagal ganglia, in the absence of elevated levels of circulating pro-inflammatory cytokines. C. jejuni treatment activated neurons in the nTS, as well as in brain regions associated with primary viscerosensory pathways and the central autonomic network. These findings provide evidence that peripheral sensory neurons contribute an early signal to the brain regarding potential pathogens. 相似文献
42.
Senescence-associated changes in the prostate are believed to play an important role in the genesis of prostate cancer. In order to provide further information on how aging increases the prostate susceptibility to cancer, we examined the pattern of cyclooxygenase (COX)-2 expression and the concomitant alterations in prostaglandin E(2) (PGE(2)) synthesis in the prostate glands of 4-, 10-, 50- and 100-week-old Fischer 344 rats. This was carried out in the prostatic areas where hormone-induced tumors arise, namely the periurethral ducts of the dorsolateral prostate (DLP). Age-associated changes were also evaluated for pro- and anti-apoptotic factors linked to COX-2 signaling and known to be involved in the normal development of the prostate gland as well as in carcinogenesis. COX-2 expression was increased in the DLP in an age-dependent manner where senescent rats had >3-4-fold higher COX-2 mRNA and protein levels than their juvenile counterparts (P<0.05). The age-related changes in COX-2 were accompanied by a similar up-regulation in the PGE(2) synthesis. Evaluation of mediators of apoptotic signaling showed a significant (P<0.05) decline in the expression levels of the pro-apoptotic BAX (>6-fold) and peroxisome proliferator-activated receptor gamma (>3-fold) and in caspase-3 activity (>2-fold) and an up-regulation of the anti-apoptotic Bcl(2) (>8-fold), PKCalpha (>2-fold) and pAkt (>4-fold) in the 100-week-old rats versus the 4-week-old animals. There was an approximately 15-fold age-dependent decrease in the pro-apoptotic ratio BAX:Bcl(2) and an increase in the anti-apoptotic variable PKCalpha(*)Bcl(2)/BAX in the senescent rats compared with the juvenile ones. These results suggest that increased COX-2 expression can be linked to the decline in the pro-apoptotic signaling in the prostate gland during aging. Subsequently, COX-2 inhibitors can be considered as a promising class of agents to attenuate the increased cell survival and, hence, protect against tumorigenesis in the aging prostate. 相似文献
43.
Badawi AF Badr MZ 《International journal of cancer. Journal international du cancer》2003,103(1):84-90
Cyclooxygenase-2 (COX-2) expression and peroxisome proliferator-activated receptor-gamma (PPARgamma) inactivation are linked to increased risk of human breast cancer. The purpose of our study was to examine the relationship between COX-2 (with the resulting prostaglandins E(2), PGE(2)) and PPARgamma (and its natural endogenous ligand 15-Deoxy-Delta(12,14)-prostaglandin J(2), 15d-PGJ(2)) at various stages during the development of human breast cancer and its progression to metastasis. Human breast tissue specimens were collected from normal breasts or from individuals with fibrocystic disease and served as controls (n = 22). Tissues were also collected from uninvolved (n = 25), tumor (n = 25) and lymph node metastasis (n = 15) regions from breast cancer patients. COX-2 and PPARgamma mRNA expression were increased and downregulated, respectively, in tissues from cancer patients compared to controls. Metastatic tissues tended to have higher alterations compared to non-metastatic tissues (p < 0.05). These altered expressions in COX-2 and PPARgamma were paralleled by increases in the tissue levels of PGE(2) and decreases in 15d-PGJ(2). A significant inverse correlation was found between PGE(2) and 15-d-PGJ(2) (r = -0.51, p < 0.05). Significant correlations (p < 0.05) were also obtained between COX-2 and PPARgamma mRNA (inverse, r = -0.72) and between COX-2 and PGE(2) (direct, r = 0.68). Increases in COX-2 mRNA expression and levels of PGE(2) and down-regulation of PPARgamma mRNA expression and 15d-PGJ(2) levels were characterized as predictors of breast cancer risk (p < 0.05). Our results suggest that the altered expression of COX-2 and PPARgamma and the subsequent modulation in the tissue levels of PGE(2) and 15-d-PGJ(2) may influence the development of human breast cancer and its progression to metastasis. 相似文献
44.
Inhibition of 5-lipoxygenase activating protein decreases proteinuria in diabetic rats 总被引:4,自引:0,他引:4
BACKGROUND: The binding of 5-lipoxygenase (5-LO) to the 5-LO activating protein (FLAP) is a prerequisite for subsequent formation of leukotrienes (LT) from arachidonic acid. We have shown that FLAP antagonist administration decreased proteinuria in glomerulonephritic patients. In this follow-up study, we assessed the role for FLAP in a rat model of streptozotocin-induced diabetic nephropathy. METHODS: Diabetic rats were treated for 4 weeks with FLAP (BAY X-1005, 200 mg/kg) or 5-LO (Zileuton, 80 mg/Kg) antagonists. Proteinuria, renal function and LT production was assessed. We also determined protein permeability of cultured glomerular endothelial cells (which possess no 5-LO) by measuring their permeability to radiolabeled albumin with and without FLAP antagonists. RESULTS: FLAP mRNA levels increased dramatically in glomeruli from diabetic animals compared to controls. Inhibition of FLAP (but not inhibition of 5-LO) reduced proteinuria, with no effect on estimated glomerular filtration rate. Interestingly, diabetes-induced rises in urinary excretion and glomerular production of leukotrienes were not modified by the inhibitors. Increased FLAP expression in glomerular endothelial cells in culture was associated with an increase in albumin permeability, and this increase was abolished by FLAP antagonists. On the other hand, addition of LTA(4) led to increases in leukotriene formation and in permeability. This increase in permeability was also reduced by co-incubation with FLAP antagonists, whereas the increase in leukotriene synthesis was not modified. CONCLUSIONS: These results suggest a role for FLAP other than the activation of 5-LO, possibly in protein handling, and point to FLAP antagonists as anti-proteinuric agents. 相似文献
45.
Badr Hel-S 《The Journal of the Egyptian Public Health Association》2003,78(3-4):319-339
Industrialization has provided humanity with many material and social benefits. Unfortunately, it has also brought about many material and social problems, one of which is environmental pollution that nowadays poses a major threat not only to humans, but also to all life on earth. The aim of the present study is to assess the level of environmental awareness among high school teachers in Kuwait; to study the extent of their environmental worry; and to evaluate the relationship between their environmental awareness and worry, and how they vary with different socio-demographic variables. A cross sectional study of 461 high school teachers was conducted using a random multistage cluster sample design. The target population comprised public high school teachers (males and females) in 2 governorates, Hawalli and Ahmadi. Data collection was performed using a structured anonymous self-administered questionnaire covering the environmental awareness and environmental worry checklists. The sample involved 499 teachers. About 60% of the teachers had high level of environmental awareness and almost half of them had high level of environmental worry. Both scores increased with increasing age, years of experience, level of education of the spouse, presence of children and being non-Kuwaiti. Males scored higher in both scores, but the difference was only significant in the part concerning environmental worry. The level of teachers' environmental worry was significantly positively related to their environmental awareness. 相似文献
46.
Dahniya MH Hanna RM Ashebu S Muhtaseb SA el-Beltagi A Badr S el-Saghir E 《The British journal of radiology》2001,74(879):283-289
On reviewing our cases of hydatid disease seen over a period of 20 years (1978-1998), we encountered a number of unusual radiological appearances and sites, which are demonstrated in this pictorial review. We briefly discuss the pathology of hydatid disease and its complications. 相似文献
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49.
The extensive care a ventilator-assisted child (VAC) requires when cared for in the home can impact the mother's ability to participate in health promotion activities. The purpose of this study was to examine health promotion activities and the relationships among functional status of the child, impact of the illness on the family, coping, social support, and health promotion activities of mothers who care for ventilator-assisted children at home. Thirty-eight primary female caregivers, mostly mothers, participated in the study and completed the Personal Lifestyle Questionnaire (PLQ), measures of child's functional status, impact of the illness on the family, coping, social support, and demographic data. Findings revealed that the mothers scored low on the nutrition, exercise, relaxation, and general health promotion subscales of the PLQ. Functional status of the child and coping were positively correlated with participation in health promotion activities, whereas impact of the child's illness on the family was inversely related to health promotion of the mothers. Regression analysis revealed that functional status of the child and coping were significant predictors of mothers' participation in health promotion activities. The high demands associated with caring for a VAC with poor functioning can be a significant risk factor for not participating in health promotion activities. Nurses need to help mothers with coping and finding resources to help mediate the stress related to caring for their child, thereby helping the mothers to maintain their own health. 相似文献
50.
Badr G Sayed D 《The Egyptian journal of immunology / Egyptian Association of Immunologists》2006,13(2):23-31
Cytokines play important roles in the growth and growth arrest of cancer cells. IL-13 via an IL-4R alpha/IL-13R alpha 1 heterocomplex receptor inhibits the growth of renal cell carcinoma cells (RCC). However, it does not inhibit the growth of glioblastoma cells that express the IL-13R alpha 2 chain. In the present studies we investigated whether melanoma cells express IL-13R alpha 1 and IL-13R alpha 2 chains as well as whether they respond to IL-13. Membrane IL13R alpha 2 was co-expressed with IL-4R alpha and IL-13R alpha 1 chains in three of six tested melanoma cell lines. Furthermore, the IL-13R alpha 2 positive cell lines, release a soluble form of IL-13R alpha 2, specifically under IL-13 but not IL-4 stimulation. The release of soluble IL-13R alpha 2 was inhibited by various metalloproteinase inhibitors and EDTA inhibits the biological response to IL-13. 相似文献