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51.
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53.
Leptin induces cell migration and the expression of growth factors in human prostate cancer cells 总被引:15,自引:0,他引:15
Frankenberry KA Somasundar P McFadden DW Vona-Davis LC 《American journal of surgery》2004,188(5):560-565
BACKGROUND: The adipocyte hormone leptin has been shown to increase migration and angiogenesis in epithelial cells. Therefore, we hypothesized that leptin would induce prostate cancer cell migration and growth factor expression in vitro. METHODS: Prostate cancer cell lines DU145 and PC-3 (androgen-resistant) were treated with leptin over time. Supernatants were assayed for growth factor expression via enzyme-linked immunosorbent assay (ELISA). Becton Dickinson-Falcon Transwell systems were used to assay leptin-induced migration. RESULTS: Leptin significantly induced expression of vascular endothelial growth factor (VEGF), transforming growth factor-beta1 (TGF-beta1), and basic fibroblast growth factor (bFGF) in DU145 and PC-3 cells. Prostate cancer cell migration was enhanced by leptin and inhibited 50% to 70% with the addition of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) inhibitors. CONCLUSIONS: The mitogenic effects of leptin on cancer cells, in combination with the increased migration and expression of growth factors, overall likely contributes to the progression of prostate cancer. Therefore, obesity associated with high leptin levels should be considered a risk factor in prostate cancer patients. 相似文献
54.
Introduction. Inflammatory mediators have been implicated in the onset and progression of acute pancreatitis (AP). The signaling pathways affected by inflammation in pancreatic cells are still largely unknown. SOCS proteins are cytokine-induced cytokine signaling inhibitors that terminate the inflammatory response. Our previous studies show that SOCS-3 mRNA levels are up regulated in response to bacterial lipopolysaccharide (LPS) or inflammation (TNFα) in acinar cells. With the addition of IL-6 or IL-1β, SOCS-3 expression is down regulated. Since SOCS-3 proteins are known to affect the JAK/STAT pathway, we hypothesized that LPS and TNFα, in combination with the proinflammatory cytokines IL-6 and IL-1β, would mediate STAT3 mRNA expression in pancreatic acinar cells. Methods. Rat pancreatic acinar cells (AR42J) were treated with either LPS (10 μg/ml) or TNF-α (10, 100, or 200 ng/ml) in the presence or absence of IL-6 (20 ng/ml) or IL-1β (10 ng/ml) for 0, 15, 30, 45, 60, 180, or 360 min. Total RNA extracted at each time point was used in multiplex RT-PCR reactions to determine STAT3 mRNA expression. Values were standardized to 18S rRNA. Results. STAT3 mRNA expression was significantly (P < 0.05) increased by 3 h in acinar cells treated with either LPS or TNFα. At the highest concentration of TNFα, the addition of IL-6 and IL-1β significantly (P < 0.05) enhanced STAT3 mRNA expression. When added in combination with the proinflammatory cytokines IL-6 or IL-1β, LPS-induced STAT3 expression remained elevated without further change. Conclusions. STAT3 expression was increased in response to endotoxin and proinflammatory cytokines, suggesting that STAT3 plays a role in initiating the inflammatory response in pancreatic acinar cells. These results indicate that inhibition of pancreatic STAT3 expression is a potential therapeutic strategy during the onset of acute pancreatitis. 相似文献
55.
OBJECTIVE:
Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.DESIGN:
A double-blind, randomized placebo controlled trial.SETTING:
Level-III neonatal intensive care unit.POPULATION STUDIED:
Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.INTERVENTION:
Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.RESULTS:
Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.CONCLUSIONS:
Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected. 相似文献56.
Ødegård RA Vatten LJ Nilsen ST Salvesen KA Vefring H Austgulen R 《Obstetrics and gynecology》2001,98(2):289-294
OBJECTIVE: To study the association between umbilical plasma levels of interleukin-6 (IL-6) in relation to fetal growth in subgroups of preeclampsia, and in control pregnancies. METHODS: Umbilical cord plasma was collected from 12,804 consecutive births. A total of 271 singleton cases of preeclampsia were identified, and classified as mild or severe, and as disease with early or late onset. As controls, 611 singleton pregnancies without preeclampsia were selected, and the ratio between observed and expected birth weight was used as a measure of fetal growth. In the analysis, we also included maternal smoking during pregnancy. Umbilical cord plasma IL-6 concentration was measured with an IL-6 bioassay. Comparing controls with subgroups of preeclampsia (severe and early onset), this study had a statistical power of 90% to detect a difference in cord IL-6 of 10 pg/mL. RESULTS: In severe preeclampsia, cord plasma IL-6 concentration was lower than among controls (P <.001), and there was a sharp decrease in cord plasma IL-6 with decreasing birth weight ratio (P trend <.001). By further dividing the preeclampsia group into early or late onset, the strong association between low IL-6 levels and low birth weight ratio appeared to be present mainly in early-onset disease. These results were not confounded by maternal smoking. CONCLUSION: Restricted fetal growth related to preeclampsia is associated with reduced umbilical cord plasma IL-6 concentration in cases with early-onset disease. In these cases, fetal growth restriction could be mediated by impaired trophoblast function. 相似文献
57.
58.
ABSTRACT. Milt7eacute;nyi, M., Pohlandt, F., Bóka, G. and Kun, E. (2nd Department of Paediatrics, Semmelweis University, Medical School, Budapest, Hungary, and the Section of Neonatology, Centre of Paediatrics, University of Ulm, Federal Republic of Germany). Tubular proteinuria after perinatal hypoxia. Acta Paediatr Scand, 70:399, 1981.–Urinary total protein (UTP) and urinary protein pattern have been studied in 23 newborn infants with Apgar scores ±S3 at one minute or acidosis (pH ±7.15) on the first day. On the first and second day UTP excretion was increased in 13 out of 18 patients. At this time the excretion of low molecular weight microproteins (T-4 and T-5) was elevated in 12 patients without increased plasma urea concentration in any case. The increased excretion of the smallest microproteins T-4/T-5 is an early sign of an impaired tubular function. 相似文献
59.
A model of corrective gene transfer in X-linked ichthyosis 总被引:5,自引:0,他引:5
Freiberg RA; Choate KA; Deng H; Alperin ES; Shapiro LJ; Khavari PA 《Human molecular genetics》1997,6(6):927-933
Single gene recessive genetic skin disorders offer attractive prototypes
for the development of therapeutic cutaneous gene delivery. We have
utilized X-linked ichthyosis (XLI), characterized by loss of function of
the steroid sulfatase arylsulfatase C (STS), to develop a model of
corrective gene delivery to human skin in vivo. A new retroviral expression
vector was produced and utilized to effect STS gene transfer to primary
keratinocytes from XLI patients. Transduction was associated with
restoration of full-length STS protein expression as well as steroid
sulfatase enzymatic activity in proportion to the number of proviral
integrations in XLI cells. Transduced and uncorrected XLI keratinocytes,
along with normal controls, were then grafted onto immunodeficient mice to
regenerate full thickness human epidermis. Unmodified XLI keratinocytes
regenerated a hyperkeratotic epidermis lacking STS expression with
defective skin barrier function, effectively recapitulating the human
disease in vivo. Transduced XLI keratinocytes from the same patients,
however, regenerated epidermis histologically indistinguishable from that
formed by keratinocytes from patients with normal skin. Transduced XLI
epidermis demonstrated STS expression in vivo by immunostaining as well as
a normalization of histologic appearance at 5 weeks post-grafting. In
addition, transduced XLI epidermis demonstrated a return of barrier
function parameters to normal. These findings demonstrate corrective gene
delivery in human XLI patient skin tissue at both molecular and functional
levels and provide a model of human cutaneous gene therapy.
相似文献
60.
A monokine regulates colony-stimulating activity production by vascular endothelial cells 总被引:20,自引:0,他引:20
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA. 相似文献