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排序方式: 共有641条查询结果,搜索用时 209 毫秒
41.
Blepharitis due to Demodex: myth or reality?]   总被引:6,自引:0,他引:6  
PURPOSE: Demodex folliculorum has been incriminated in the development of blepharitis although much controversy persists. Certain authors suggest that Demodex is a direct pathogen in chronic palpebral conditions while others consider the saprophyte to be innocuous to skin. METHODS: We conducted a prospective study of eyelashes in 100 persons, searching for Demodex folliculorum and chronic blepharitis. Microscopy in immersion oil after storage in a moist chamber was performed. RESULTS: The incidence of Demodex folliculorum was very high in patients with blepharitis compared with normal controls. Incidence increased with age. Harmless cuffs around the base of the eyelashes was found in 4% with Demodex irradior. CONCLUSION: Demodex should be considered as the cause of chronic blepharitis. Anti-Demodex treatment is indicated when the parasite is found.  相似文献   
42.
43.
目的:采用解剖M-型超声技术评价冠状动脉内支架置入术前后左室局部室壁运动的改变。方法:30例行左前降支(LAD)支架置人术的患者,在术前72h内、术后72h内以及3个月时分别进行超声心动图检查,在左室短轴二尖瓣切面和乳头肌切面的二维图像中获取前间隔、前壁、侧壁、后壁、下壁和后间隔等节段的解剖M-型超声图像,测量这些节段的室壁收缩期增厚率。结果:30例患者术后72h内检查显示,LAD对应节段(前壁和前间隔)的收缩期增厚率较术前显著增高。25例患者完成3个月随访,其LAD对应节段的术后72h以及术后3个月时的室壁收缩期增厚率,均较术前显著增高。结论:冠状动脉内支架置入术能迅速改善狭窄动脉供血区域的室壁运动,并维持至少3个月;采用解剖M-型超声技术测量室壁节段的收缩期增厚率,能准确评价支架置入术的疗效。  相似文献   
44.
OBJECTIVES: To test the association between hyperhomocysteinemia (HHC) and deep venous thrombosis (DVT) of lower extremities in Tunisians. DESIGN AND METHODS: This case-control study included 90 patients with DVT of the lower extremities and 160 healthy controls. Plasma homocysteine, vitamin B(12) and folate were determined using immunoenzymatic methods. Logistic regression models were performed to test whether the association between HHC and DVT is independent and to precise determinants of HHC in DVT patients. RESULTS: Plasma total homocysteine concentrations were significantly higher in patients with DVT (17.4+/-11.5 micromol/L) and in patients with idiopathic DVT (15.2+/-6.4 micromol/L) as compared to controls (11.5+/-3.3 micromol/L). HHC was significantly associated (p<0.001) with all DVT (OR, 8.82; 95% CI, 3.96-19.6) as well as idiopathic DVT (OR, 7.40; 95% CI, 3.01-10.8). These associations persisted after adjustment for several thrombosis risk factors. In patients with DVT, HHC was related to folate and vitamin B(12) concentrations, but neither to the type of occurrence nor to the recurrence of DVT. CONCLUSION: HHC is independently associated with first DVT of lower extremities in Tunisians. Homocysteine should be assessed in patients with DVT and the effect of vitamin B supplementation should be tested among them.  相似文献   
45.
目的 :应用超声定量组织速度显像 (QTVI)技术测定二尖瓣环运动速度 ,评价其是否与左室整体收缩功能指标左室射血分数 (L VEF)相关。方法 :5 0例冠状动脉疾病患者 (冠心病组 )和 2 5例正常人 (对照组 ) ,从心尖四腔、两腔和长轴切面观中测定后间隔、侧壁、前壁、下壁、前间隔和后壁六个部位的二尖瓣环收缩期平均峰值速度 (Sm)以及心电图 QRS波起始至二尖瓣环收缩波峰值的时间 (Q- Sm) ,并与心尖四腔观单平面改良 Simpson法所测 L VEF作相关性分析。结果 :冠心病组六个部位的二尖瓣环 Sm平均值 (5 .2 1± 1.12 ) cm / sec与 L VEF呈显著正相关 (r=0 .6 6 ,P<0 .0 0 0 1) ,对照组六个部位的 Sm平均值 (6 .0 2± 0 .83) cm/ sec亦与 L VEF显著正相关 (r=0 .6 5 ,P<0 .0 0 0 1)。 Q- Sm和心率则与 L VEF无显著相关性。结论 :应用 QTVI技术测定收缩期二尖瓣环运动可反映左室整体收缩功能 ,有一定临床应用价值  相似文献   
46.
Vitamin E and coronary heart disease in Tunisians   总被引:3,自引:0,他引:3  
BACKGROUND: Vitamin E (VE) is thought to be effective in preventing atherosclerosis. However, to date no consistent relationship has been identified between VE and coronary heart disease (CHD). This study was designed to assess the degree of association between VE and CHD in a sample of the Tunisian population. METHODS: Sixty-two angiographically confirmed coronary atherosclerotic patients and 65 age- and sex-matched controls were included. VE was measured in plasma and in the LDL fraction by HPLC. Cholesterol, triglycerides, and phospholipids were measured by enzymatic methods. RESULTS: A trend toward a meaningful decrease of plasma VE was observed in affected patients compared with controls (P: = 0.06). VE concentrations standardized for cholesterol and lipid concentrations were significantly lower (P: <0.02) in coronary patients than in controls (4.35 +/- 1.03 vs 4.82 +/- 1.23 mmol/mol for cholesterol-adjusted VE and 2.35 +/- 0.56 vs 2.66 +/- 0.65 mmol/mol for lipid-adjusted VE, respectively). In the LDL fraction, only cholesterol-standardized VE was significantly lower in cases than controls (3.84 +/- 1.13 vs 4.41 +/- 1.16 mmol/mol). This association between VE and CHD remained unchanged independent of age, sex, smoking habit, hypertension, and diabetes. In CHD patients, lower lipid-adjusted VE was associated with enhanced LDL susceptibility to oxidation but without alteration of the serum fatty acid profile. CONCLUSIONS: These results support the hypothesis that VE plays a role in preventing atherosclerosis.  相似文献   
47.
Ceratonia siliqua is a typical Mediterranean plant, mainly used in food and Tunisian traditional folk medicine. Among the tested extracts, the ethyl acetate fraction (EACs) exhibited the highest total phenolic and flavonoids content. The antioxidant activity in vitro systems showed a more significant potent free radical scavenging activity of this extract than other analysis fractions. The HPLC finger print of EACs active extract showed the presence of six phenolic compounds. The in vivo results showed that oral administration of CCl4 enhanced levels of hepatic and renal markers (ALT, AST, ALP, LDH, γ-GT, urea and creatinine) in the serum of experimental animals. It also increased the oxidative stress markers resulting in increased levels of the lipid peroxidation with a concomitant decrease in the levels of enzymatic antioxidants (SOD, CAT, GPx) in both liver and kidney. The pre-treatment of experimental rats with 250 mg/kg (BW) of the EACs, by intraperitoneal injection for 8 days, prevented CCl4 induced disorders in the levels of hepatic and kidney markers. The biochemical changes were in accordance with histopathological observations suggesting a marked hepatoprotective and nephroprotective effect of the EACs extract.  相似文献   
48.
The CTLA-4 genetic variation, such as single nucleotide polymorphisms (SNPs) may be critical and can affect the functional activity of cells that initiate the graft-versus-host disease (GVHD) effects. The aim of this study is to examine the effect of donor CTLA-4 alleles and haplotypes for the -318C>T and the 49A>G polymorphisms on the occurrence of GVHD in Tunisians recipients of HSCs. A total of 112 patients and their 112 respective sibling donors of HSCs were enrolled in this study. All patients had either grades 0-I or grades II-IV acute GVHD, or chronic GVHD. The SNPs genotyping assay was performed using sets of sequence specific primers (SSP-PCR). The single marker association analysis showed that the 49G allele, in a genetic recessive model, may be a potential risk factor only for the chronic GVHD (p = 0.032, odds ratio [OR] = 2.58, 95% confidence interval = 1.05-6.32). The haplotypes analyses showed that the CTLA-4 -318C49G nucleotide combination is significantly associated with the incidence of chronic GVHD (p = 0.043, χ2 = 3.27). Donor CTLA-4 -318C49G haplotype may be a significant risk factor for developing chronic GVHD after allo-stem cell transplantation. We suppose that donor T cells expressing this haplotype in a homozygous state have higher proliferation than those expressing other haplotypes, especially after recognition of the recipient's minor histocompatibility antigens.  相似文献   
49.
Our aim was to test the normality of physical activity patterns and energy expenditures in normal weight and overweight primary school students. Heart rate estimates of total daily energy expenditure (TEE), active energy expenditure (AEE), and activity patterns were made over 3 consecutive school days in healthy middle-class Tunisian children (46 boys, 44 girls, median age (25th-75th) percentile, 9.2 (8.8-9.9) years. Our cross-section included 52 students with a normal body mass index (BMI) and 38 who exceeded age-specific BMI limits. TEE, AEE and overall physical activity level (PAL) were not different between overweight children and those with a normal BMI [median values (25th-75th) 9.20 (8.20-9.84) vs. 8.88 (7.42-9.76) MJ/d; 3.56 (2.59-4.22) vs. 3.85 (2.77-4.78) MJ/d and 1.74 (1.54-2.04) vs. 1.89 (1.66-2.15) respectively]. Physical activity intensities (PAI) were expressed as percentages of the individual’s heart rate reserve (%HRR). The median PAI for the entire day (PAI24) and for the waking part of day (PAIw) were lower in overweight than in normal weight individuals [16.3 (14.2-18.9) vs. 20.6 (17.9-22.3) %HRR, p < 0.001) and 24.8 (21.6-28.9) vs.26.2 (24.5-30.8) %HRR, p < 0.01], respectively. Overweight children allocated more of their day to sedentary pursuits [385 (336-468) vs 297 (235-468) min/d, p < 0.001], and less time to moderate physical activity [381(321-457) vs. 460 (380-534) min/d, p < 0.01]. Nevertheless, because of the greater energy cost of a given task, total and active daily energy expenditure did not differ from those with a normal BMI.

Key points

  • The physical activity intensity for the entire day (PAI24) and for the waking part of day (PAIw) were lower in overweight than in normal weight individuals.
  • However, because the energy cost of activity is greater in those who are overweight, they do not differ in total energy expenditure or in active energy expenditure.
  • Normal children spend more time in moderate activity and less time in sedentary pursuits than overweight children.
Key words: Heart rate monitoring, activity patterns, energy expenditure, excess weight, obesity.  相似文献   
50.
Adult bone marrow (BM)-derived insulin-producing cells (IPCs) are capable of regulating blood glucose levels in chemically induced hyperglycemic mice. Using cell transplantation therapy, fully functional BM-derived IPCs help to mediate treatment of diabetes mellitus. Here, we demonstrate the detection of the pentose phosphate pathway enzyme, transketolase (TK), in BM-derived IPCs cultured under high-glucose conditions. Benfotiamine, a known activator of TK, was not shown to affect the proliferation of insulinoma cell line, INS-1; however, when INS-1 cells were cultured with oxythiamine, an inhibitor of TK, cell proliferation was suppressed. Treatment with benfotiamine activated glucose metabolism in INS-1 cells in high-glucose culture conditions, and appeared to maximize the BM-derived IPCs ability to synthesize insulin. Benfotiamine was not shown to induce the glucose receptor Glut-2, however it was shown to activate glucokinase, the enzyme responsible for conversion of glucose to glucose-6-phosphate. Furthermore, benfotiamine-treated groups showed upregulation of the downstream glycolytic enzyme, glyceraldehyde phosphate dehydrogenase (GAPDH). However, in cells where the pentose phosphate pathway was blocked by oxythiamine treatment, there was a clear downregulation of Glut-2, glucokinase, insulin, and GAPDH. When benfotiamine was used to treat mice transplanted with BM-derived IPCs transplanted, their glucose level was brought to a normal range. The glucose challenge of normal mice treated with benfotiamine lead to rapidly normalized blood glucose levels. These results indicate that benfotiamine activates glucose metabolism and insulin synthesis to prevent glucose toxicity caused by high concentrations of blood glucose in diabetes mellitus.  相似文献   
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