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101.
ObjectiveTo evaluate in vivo antioxidant and hepatoprotective activities of the methanolic extract of the root of Cassia singueana in rats following acute and chronic carbon tetrachloride intoxication.MethodsMalondialdehyde (MDA), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin as indices of liver damage and lipid peroxidation were detected in rats after intraperitoneal administration of extract (5 mg/kg).ResultsThe liver, kidney and heart showed significant reduction (P<0.05) in the levels of MDA from (0.18±0.04), (0.23±0.07) and (0.26±0.10) nmol/mg respectively in the CCl4 control to (0.15±0.03), (0.17±0.04) and (0.17±0.07) nmol/mg protein in groups pre-treated with the extract for three days at 5 mg/kg). Similarly, compared to the CCl4 control, significant reduction (P<0.05) in serum AST, ALT and bilirubin as well as in level of total cholesterol and MDA with concomitant increase in HDL cholesterol, superoxide dismutase and catalase levels when CCl4-intoxicated rats were treated with Cassia singueana root extract for two weeks.ConclusionsThese results suggest that methanolic extract of Cassia singueana contain potent antioxidant compounds that can offer significant protection against hepatic and oxidative injuries.  相似文献   
102.
103.
Objectivethis study was performed to determine the predictive capacity of four different bioelectrical impedance analysis (BIA) devices in the assessment of adolescents, with and without a protocol.Methodsa cross-sectional study was performed with 215 adolescents aged 10 to 14 years, of both genders, evaluated through anthropometry and body composition by dual energy X-ray absorptiometry (DXA) and by four different BIA devices, with and without a protocol. The following tests were used: Kolmogorov-Smirnov's, chi-squared, Student's t or Mann-Whitney's, Kruskal-Wallis's, Wilcoxon's, and kappa index. The ROC curves were constructed and the sensitivity, specificity, and positive and negative predictive values were calculated.Resultsof the 215 adolescents, 44.2% had excessive body fat. The tetrapolar BIA device equipped with eight tactile electrodes showed more sensitivity and results that were closer to those obtained by DXA (area under the ROC curve [AUC] = 0.964 with protocol and AUC = 0.973 without protocol, p < 0.001), as well as greater agreement (k = 0.67 with protocol and k = 0.63 without protocol, p < 0.001). The evaluation without protocol was similar to that by DXA in most investigated situations (p > 0.05).ConclusionBIA is capable of predicting alterations in adolescents’ body composition. When it is impossible to perform the assessment with a protocol, its results may be useful in population studies.  相似文献   
104.

Introduction and Objective

Studies in adults have shown an association between increased adiposity and hypertension, but few studies have analyzed this association in childhood. The aim of this study was to investigate the association between blood pressure (BP) and body adiposity indicators in children, controlling for the variables of birth conditions, sociodemographics, lifestyle and diet.

Methods

In this cross‐sectional study of 399 children aged 4 to 7 years, the dependent variable was BP, measured according to the protocol established by the 7th Brazilian Guidelines on Hypertension. The explanatory variables of the study were waist‐to‐height ratio (WHtR) and body mass index (BMI). Multiple linear regression was used to assess the independent association between adiposity and BP indicators adjusted for the variables of birth conditions, sociodemographics, lifestyle and diet. Statistical significance was set as α=5%.

Results

BMI for age and WHtR correlated positively with systolic (SBP) and diastolic blood pressure (DBP). After multivariate analysis, higher values of BMI (model 1) and WHtR (model 2) were associated with increased SBP and DBP.

Conclusion

Increased body adiposity, as assessed by BMI and WHtR, was associated with increased SBP and DBP among the children studied. Thus, we suggest the use of BMI and WHtR in the nutritional assessment of children to detect changes in BP and other cardiometabolic risk factors in this population.  相似文献   
105.
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
106.
A bleeding diathesis caused by platelet dysfunction is a major cause of morbidity and mortality in patients with uremia. Platelet adhesion to vascular subendothelium is defective in uremia and depends on the interactions of the platelet glycoprotein (GP) Ib/IX complex with the vascular wall. We measured levels of platelet surface GPIb, platelet surface GPIX, plasma glycocalicin (a product of enzymatic cleavage of GPIb), and ristocetin-induced platelet agglutination (RIPA) in patients undergoing chronic hemodialysis compared with patients undergoing peritoneal dialysis and healthy controls. Patients undergoing chronic maintenance hemodialysis have higher levels of platelet surface expression of GPIb (187+/-10 fluorescent units; P < 0.001) than either healthy controls (120+/-4 fluorescent units; P < 0.001) or patients undergoing peritoneal dialysis (127+/-5 fluorescent units; P < 0.001). Similar changes were observed in platelet surface GPIX. Plasma glycocalicin levels were elevated in chronic hemodialysis patients (71+/-5 nmol/L) compared with healthy controls (36+/-3 nmol/L; P < 0.001). Plasma glycocalicin levels also increased progressively throughout the hemodialysis procedure. The slope of RIPA was significantly lower in chronic hemodialysis patients (46+/-3) than in either healthy controls (67+/-4; P < 0.05) or peritoneal dialysis patients (62+/-2; P < 0.05). In conclusion, patients undergoing chronic maintenance hemodialysis have increased plasma glycocalicin levels and decreased RIPA, which may contribute to diminished platelet adhesion to vascular subendothelium and increased bleeding associated with uremia.  相似文献   
107.
The two types of neurophysins known in vertebrate species, namely MSEL-neurophysin (vasopressin-like hormone-associated neurophysin) and VLDV-neurophysin (oxytocin-like hormone-associated neurophysin) have been purified from the pollack (Pollachius virens) pituitary through a combination of molecular sieving and high-pressure liquid chromatography (HPLC). Homogeneity has been checked by gel electrophoresis and rerun in HPLC. The apparent molecular masses measured by SDS-electrophoresis are near 12 kDa, significantly higher than those found for their mammalian homologues (10 kDa). The two types of neurophysins have been recognized through their N-terminal amino acid sequences. The primary structure of MSEL-neurophysin has been partially determined using automated Edman degradation applied on native and reduced-alkylated protein, as well as peptides derived by trypsin or staphylococcal proteinase hydrolyses. Comparison of pollack MSEL-neurophysin with ox, goose and frog counterparts reveals that particular positions in the polypeptide chain are subjected to substitutions and that the numbers of substitutions do not seem closely related to the paleontological times of divergence between the different vertebrate classes.  相似文献   
108.
Spencer  HT; Sleep  SE; Rehg  JE; Blakley  RL; Sorrentino  BP 《Blood》1996,87(6):2579-2587
Trimetrexate (TMTX) is an anticancer drug with potential advantages over the more commonly used antifolate, methotrexate (MTX); however, its use has been limited by severe myelosuppression. Retroviral vectors containing mutant dihydrofolate reductase (DHFR) genes have been used to protect bone marrow cells from MTX, suggesting a similar approach could be used for TMTX. We first screened six variants of human DHFR to determine which allowed maximal TMTX resistance in fibroblasts. A variant enzyme containing a Leu-to-Tyr mutation in the 22nd codon (L22Y) was best, allowing a 100-fold increase in resistance over controls. Murine hematopoietic progenitor cells transduced with an L22Y- containing retroviral vector also showed high-level TMTX resistance in vitro. Mice reconstituted with L22Y-transduced bone marrow cells were challenged with a 5-day course of TMTX to determine whether hematopoiesis could be protected in vivo. Transfer of the L22Y vector resulted in consistent protection from TMTX-induced neutropenia and reticulocytopenia at levels that correlated with the proviral copy number in circulating leukocytes. We conclude that the L22Y vector is highly effective in protecting hematopoiesis from TMTX toxicity and may provide a means for increasing the therapeutic utility of TMTX in certain cancers.  相似文献   
109.
Emergency room radiography of asthma: an efficacy study   总被引:2,自引:0,他引:2  
  相似文献   
110.
Alpidem is a new imidazopyridine compound which has been selected in animal pharmacology for its anxiolytic and anticonvulsant activity, and for its high therapeutic index. In healthy volunteers, alpidem was well tolerated up to doses of 300 mg and appeared to be devoid of CNS toxic effects. An extensive clinical development plan has been carried out in Europe to test its efficacy and safety in anxious patients. In a series of 5 double-blind placebo controlled parallel group studies, alpidem was administered as a single dose in a situation of stress induced anxiety where the stress was represented by diagnostic investigations such as gastroscopy, cardiac catheterisation or minor surgical operations. In these studies, 188 patients received placebo and 188 received alpidem; their anxiety was assessed before and after the drug administration by means of visual analogue scales and state anxiety inventories. Alpidem at 50 and 75 mg was significantly better than placebo in reducing stress induced anxiety. Alpidem was then administered to patients suffering from severe generalized anxiety in doses from 50 to 150 mg/day for 3-4 weeks in 3 double-blind placebo controlled studies: 127 patients received alpidem and 80 received placebo. Patients were assessed by means of rating scales and visual analogue scales. Alpidem did show an anxiolytic activity in this patient population and was well tolerated especially with regard to CNS side-effects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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