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101.
Schoomaker  EB; Butler  WM; Diehl  LF 《Blood》1982,59(6):1213-1219
Structural membrane proteins were studied from erythrocytes (RBC) of a patient with a nonhemolytic form of hereditary elliptocytosis (HE) who developed a microcytic anemia with fragmented RBC while cobalamin (B12) deficient. Evidence is presented for qualitative changes in the patient's RBC membranes not related to a loss of structural proteins. Sensitivity of RBC to heat treatment was studied as well as quantitative changes in proteins by densitometry of 1% SDS--10% PAGE gels. Fractions of RBC of various sizes from the patient while B12 deficient all possessed a marked degree of heat sensitivity when compared to RBC from the patient after B12 repletion, normal family members, HE controls, B12-deficient controls, anemic controls, and normal controls. Because loss of spectrin (bands 1 + 2) from heat- sensitive RBC membranes in hereditary pyropoikilocytosis has been reported, the amount of spectrin relative to band 3 was measured. No decrease in the ratio of bands (1 + 2)/3 was found. In addition, no chromatographically abnormal membrane proteins were found by SDS-PAGE of the patient's RBC while B12 deficient. Our findings indicate that B12 deficiency results in an abnormal membrane with enhanced instability in some forms of HE. Since protein loss was not found, we conclude that an alteration in membrane protein interaction may be involved.  相似文献   
102.
Burger  PE; Dowdle  EB; Lukey  PT; Wilson  EL 《Blood》1994,83(7):1808-1812
Basic fibroblast growth factor (bFGF) and transforming growth factor- beta 1 (TGF-beta) have both been shown to act on hematopoietic progenitor cells. bFGF is a hematopoietic cytokine that acts on progenitor cells in concert with other cytokines to promote their proliferation. TGF-beta induces erythroid differentiation in K562 cells. To determine whether bFGF might act on progenitor cells by antagonizing the effects of cytokines that induce differentiation, we determined the effects of bFGF on the TGF-beta-mediated induction of hemoglobin synthesis in K562 cells. bFGF antagonized the TGF-beta- mediated induction of hemoglobin in a dose-dependent manner, with 0.1 ng/mL bFGF inhibiting hemoglobin induction by 40% and 10 ng/mL bFGF completely abrogating hemoglobin production. bFGF was most effective at antagonizing the TGF-beta-mediated induction of hemoglobin if it and TGF-beta were added simultaneously to K562 cells, but delayed addition of bFGF to TGF-beta-treated cultures still resulted in significant inhibition of hemoglobin synthesis. The inhibitory effects of bFGF on hemoglobin production were fully reversible, showing that bFGF did not permanently alter the phenotype of K562 cells. The hemin-mediated induction of hemoglobin synthesis in K562 cells was only partially negated by bFGF. bFGF also diminished the expression of glycophorin A on the surface of K562 cells. These results indicate that bFGF might increase progenitor/stem cell numbers by antagonizing the effects of cytokines that induce differentiation, thereby increasing the pool of proliferating progenitor/stem cells.  相似文献   
103.
The objective of our study was to investigate the efficacy of catalase in preventing the formation of peritoneal adhesions induced by cecal serosal laceration in rats. A research study was set up using a randomized complete block design. This study was performed in the Experimental Surgical Research Center, Kahramanmaras Sutcuimam University, Kahramanmaras, Turkey. Thirty Wistar albino rats were assigned to 3 groups of 10 animals each. The animals were anesthetized, a median laparotomy was performed, and the cecum was traumatized. In the final stages of surgery, the first group received 30,000 U of catalase intraperitoneally (ip) (catalase group), the second group received 2 mL of saline solution ip (isotonic group), and the last group received no treatment (control group). All rats were sacrificed on day 14. Adhesions were counted and blood samples were taken for measuring the catalase level. There were significant differences between the adhesion scores among all groups (p < .05, Kruskal-Wallis test). The catalase group had significantly lower adhesion scores than the other groups (post hoc Mann-Whitney test). At day 14, blood catalase levels in the catalase group were significantly lower than in the other groups (p < .05). We conclude that introduction of catalase into the peritoneal cavity during surgery inhibited adhesion formation.  相似文献   
104.
We report a patient with discoid lupus erythematosus (DLE) and associated allergic contact dermatitis (ACD) in the eyelids. In women, ACD caused by nail varnish is frequent and often seen in the eyelids. ACD caused by drugs (e.g. neomycin) is also frequent in this region. However, DLE with periorbital presentation without evidence of systemic or other cutaneous involvement is rare.  相似文献   
105.
The baboon oviductal epithelium differentiates into a tall columnarepithelium consisting of ciliated and secretory cells duringthe follicular phase of the menstrual cycle in response to risingoestradiol levels. The apical tips of these secretory cellsare filled with membrane-bound secretory granules. During theluteal phase when progesterone levels are elevated, the epitheliumregresses and deciliation occurs. Analysis of secretory proteinsobtained from explant culture media by SDS-PAGE followed byfluorography or Western Blots has revealed that the baboon oviductsynthesizes and secretes a high molecular weight glycoproteinduring the follicular phase of the cycle. Immunocytochemistrydemonstrated that the oviductal glycoprotein is localized tothe secretory granules of epithelial secretory cells, is oviductspecific, and that following secretion the oviductal glycoproteinbinds to the zona pellucida and periviteline space of ovulatedoocytes and embryos within the oviduct. Similar proteins havebeen characterized in other mammalian species. cDNA data showthat the complete coding sequence is 2228 bp for a protein of623 amino acids. A Genbank search showed that baboon oviductalglycoprotein has high homology to other oviductal glycoproteinsequences at both the nucleotide and amino acid levels. Studiesconducted to date probing the biological function of oviductalglycoprotein indicate that this protein plays a role in prefertilizationreproductive events (sperm capacitation; sperm-zona binding;zona penetration). Additional experiments are needed to reveala specific function and mechanism for this molecule.  相似文献   
106.
BACKGROUND: Deterioration of renal function and rise in blood pressure are clinically important side-effects of cyclosporin (CsA) treatment. Calcium antagonists may have a renoprotective effect against CsA nephrotoxicity. PURPOSE: To investigate the effect of the dihydropyridine calcium-channel blocker felodipine on renal haemodynamics, tubular sodium handling, and blood pressure in CsA- treated patients with no primary renal disease, 18 patients with various CsA-treated dermatological diseases were allocated to receive either felodipine 5 mg (extended release tablets) once daily for 4 weeks followed by placebo for 4 weeks, or vice versa, in a prospective, randomized, double-blind study. The patients were investigated before treatment and at the end of each treatment period. RESULTS: After felodipine, both glomerular filtration rate (GFR) and renal plasma flow (RPF) were significantly higher compared to placebo (89.4 +/- 17.5 (mean +/- SD) vs 79.0 +/- 15.9 ml/min and 412.0 +/- 107.6 vs 326.1 +/- 78.0 ml/min respectively, P < 0.001 for both), and filtration fraction (FF) was lower (0.22 +/- 0.03 vs 0.25 +/- 0.03, P < 0.001). Both systolic and diastolic blood pressure were lower after felodipine compared to placebo (116 +/- 11/71 +/- 7 vs 133 +/- 18/83 +/- 10 mmHg, P < 0.001 for both). Furthermore, proximal output of sodium, i.e. fractional excretion of lithium, was higher after felodipine (26.9 +/- 7.3% vs 20.4 +/- 5.5%, P < 0.001) as well as total sodium excretion (0.33 +/- 0.19 vs 0.19 +/- 0.08 mmol/min, P < 0.001). CONCLUSIONS: It is concluded, that felodipine 5 mg once daily for 4 weeks increased GFR, RPF, and sodium excretion in cyclosporin-treated dermatological patients with no primary renal disease. Furthermore, felodipine lowers blood pressure in these patients. The effects of felodipine may be due to an antagonizing effect against CsA-induced nephrotoxicity.   相似文献   
107.
108.
This study was designed to compare the effect of pretreatment with N-acetylcysteine (NAC) and β -glucan (β GLU) on inflammatory response in a rat model of sepsis. The study was performed in the animal laboratory of the Kahramanmaras Sutcu Imam University, School of Medicine. Forty rats were randomized into four groups (control, sham, NAC, and β GLU). Control and Sham groups received saline or NAC (200 mg/kg, po) in the NAC group and β GLU (50 mg/kg, po) in the βGLU group via intragastric gavage once a day for 10 days and 30 min prior to surgery. Sepsis was induced by cecal ligation and puncture (CLP) in rats. In the NAC, β GLU, and control groups, a laparotomy was performed with the CLP procedure. In the sham group, laparotomy was performed and cecum was manipulated but not ligated or perforated. TNF-α and IL-6 levels were significantly elevated in the control group and decreased in the NAC and β GLU groups. IL-10 levels were significantly increased in the β GLU group (p <. 05). Superoxide dismutase and catalase levels in the liver tissue were significantly increased in the NAC and β GLU groups, whereas superoxide dismutase levels were higher in the β GLU pretreatment group than the NAC pretreatment group (p < 0.05). Malondialdehyde levels in the liver tissue were significantly elevated in the control group and decreased in the NAC and β GLU groups (p <. 05). Prophylactic administration of NAC or β GLU similarly ameliorated sepsis syndrome by reduction of the proinflammatory cytokines and increase of the anti-inflammatory cytokine levels and accession of cellular antioxidants, which protect cells from oxidative stress, thereby recruiting inflammatory cells into tissue.  相似文献   
109.
Several skin diseases are believed to be associated with oxidative stress. Tinea pedis is an infection of the feet caused by fungi. The infectious diseases caused by dermatophytes are mainly related to the enzymes produced by these fungi. The cutaneous oxidative stress status of tinea pedis has not been demonstrated in the published work up to now. The aim of the present study was to evaluate the role of oxidative stress in affected skin areas in a group of patients with interdigital tinea pedis. Thirty‐one consecutive patients with a diagnosis of unilateral interdigital tinea pedis were enrolled. The samples were obtained by scraping the skin surface. Oxidative stress biomarkers such as superoxide dismutase, catalase and malondialdehyde levels were measured spectrophotometrically. The activities of superoxide dismutase and catalase and the levels of malondialdehyde were significantly higher on the lesional area than the non‐lesional area (P < 0.001). According to sex and fungal subtypes, there was no significant difference in the levels of oxidative stress biomarkers in patients with tinea pedis (P > 0.05). Our results suggested that antioxidant defense of lesional skin surface was higher compared to non‐lesional skin. This is possibly due to a compensatory response to various fungal infections and thereby protects the cells against oxidative damage.  相似文献   
110.
Background Warts are abnormal skin growths caused by human papilloma virus (HPV) infections within the skin of the patients. Sometimes the disease is difficult to treatment, and also, the relationship between HPV and some forms of skin cancers is important. The cutaneous oxidative stress status of warts is absent in the literature. Objectives To evaluate the role of oxidative stress in affected skin areas in a group of patients with plantar warts. Methods Thirty‐six consecutive patients with a diagnosis of plantar warts were enrolled. The samples were obtained by scraping the skin surface. Superoxide dismutase (SOD) and catalase (CAT) activities and malondialdehyde (MDA) levels were measured spectrophotometrically at samples. Results The SOD activity was significantly lower, and the MDA level was significantly higher on the lesional area than on the non‐lesional area (P < 0.001 for each), and there was no significant difference in the CAT activity between both areas (P = 0.11). Conclusion Cutaneous oxidative stress in patients with plantar warts may play a role in pathogenesis of the disease. The addition of topical drugs with antioxidative effects may be valuable in the treatment of warts.  相似文献   
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