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81.
OBJECTIVE: To evaluate the relationship between the serum concentration of TNFalphaRII and some adhesion molecules (including ICAM-1, VCAM-1, P-selectin and E-selectin) and coronary artery stenosis. DESIGN AND SETTING: Observational (cross-sectional) study in a university heart hospital in Tehran, Iran. PATIENTS: 81 patients with angiographically proven coronary artery disease were compared with 75 individuals who had undergone coronary angiography with no significant evidence of stenosis (control subjects). METHODS: Soluble adhesion molecules and TNFalphaRII were determined by enzyme-linked immunosorbent assay technique. sICAM-1 and sP-selectin values were significantly higher in patients with coronary artery disease than in control subjects (146 +/- 38 vs. 132 +/- 48 p < 0.04 and 275 +/- 107 vs. 241 +/- 104 ng/ml p < 0.04 respectively). Multiple logistic regression analysis showed sICAM-1 as an independent discriminating risk factor for coronary artery disease (p < 0.03). Prediction models that incorporated sICAM-1 in addition to other established coronary risk factors were significantly better at predicting risk than the models based on the other risk factors alone. Multiple regression analysis indicated that sP-selectin levels were greater in patients with single-vessel disease than in the respective normal (p < 0.01). CONCLUSIONS: Our findings suggest that sICAM-1 has an association with stable coronary artery disease and the evaluation of this marker may improve the coronary risk assessment in Iranian patients.  相似文献   
82.
A reversed-phase high-performance liquid chromatography method is described for the determination of oxybutynin (OXB) in human bladder samples. Following homogenization, tissue samples underwent double extraction with hexane and eventually were concentrated by freeze-drying before analysis. Chromatographic separation was performed with a mobile phase of acetonitrile-water-1 M ammonium acetate, pH 7.0 (85:13:2, v/v/v) at a flow-rate of 0.5 ml/min and double (electrochemical and UV) detection was applied. The retention time of oxybutynin eluting peak was around 18 min. Using a standard curve range of 10 to 500 ng/ml the quantification limit with electrochemical detection was 5 ng/ml with an injection volume of 100 microl. Within-day and day-to-day relative standard deviation values were 4.9 and 9.81%, respectively, while a 94% accuracy and a 72% recovery was attained. We applied this method to compare the OXB levels into bladder wall tissue samples after passive diffusion and after electromotive drug administration (EMDA), using a two-chambered poly(vinyl chloride) diffusion cell designed and developed in our laboratory. The results obtained show that EMDA enhanced OXB penetration into bladder wall and that this novel way of local drug administration can be potentially used in patients with neurogenic bladder dysfunction or urinary incontinence.  相似文献   
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Background: It seems that polymorphism in the regulatory areas of cytokine genes affects the cytokine production capacity and may play a role in the development of infectious diseases. Interleukin-10 (IL-10) and Interleukin-6 (IL-6), which are cytokines of Th2, cause the macrophage become inactive and patient conditions get worse.

Methods: In this case‐control study, 60 patients with brucellosis and 60 healthy participants were recruited. IL-10 genotyping at positions -1082 (G/A), -819 (C/T), and -592 (C/A) and IL-6 genotyping at position -174 (G/C) were analyzed by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods. The levels of IL-10 and IL-6 were determined by a sandwich enzyme-linked immunosorbent assay in sera of study population.

Results: The AA and CC genotypes of the IL-10 gene at positions -1082 G/A and -819 C/T were significantly more frequent in patients in comparison to controls, respectively. The AG genotype of the IL-10 gene at positions -1082 G/A was significantly more frequent in control groups than the patients. Serum levels of IL-10 and IL-6 were significantly more frequent in the patients than in the control groups.

Conclusions: Our study showed that the AA and CC genotypes at positions -1082 and -819 are very important, respectively. These results suggest that IL-10 (-1082 G/A) GG genotype may be considered as a risk factor for brucellosis, while the AG genotype might be a protective factor against the disease.  相似文献   

86.
BACKGROUND: The STAN methodology has been shown to reduce both operative delivery for fetal distress and the cord artery metabolic acidosis rate. OBJECTIVE: The objective of this study was to monitor delivery modes and perinatal outcomes following the introduction of the STAN methodology and the evolution of its use at our institution. METHODS: Two periods were characterized: June 2000-June 2002 (period 1) and July 2002-April 2005 (period 2). Parity, mode of labor and delivery, ST events, and neonatal outcome (Apgar score and pH of the umbilical cord artery and vein), cases of metabolic acidosis and operative delivery for fetal distress were studied. RESULTS: One thousand eight hundred and eighty-nine women were included in the study. The rate of use of STAN increased from 13.5% to 16% over these two time periods. The rate of metabolic acidosis was low: 0.28% and 0.45%, respectively. No cases of neonatal encephalopathy or of perinatal death were diagnosed. There was a decrease in the rate of operative delivery for fetal distress (163/701 (22.9%) vs. 228/1111 (20.3%), p = 0.26). CONCLUSIONS: According to the literature, our use of the STAN appears to be very successful; the metabolic acidosis rate was 0.38% and the rate of operative delivery for fetal distress decreased. We improved the accuracy of the interpretation of the fetal heart rate.  相似文献   
87.
Cardiac attacks and sudden cardiac deaths are more common in cold seasons. Up to now the underlying pathophysiologic mechanism of the seasonal variation in cardiovascular accidents is scarcely known. There are many physiological mechanisms which exhibit seasonal variation (e.g. blood pressure). Nitric oxide (NO) is a potent vasodilator, and impaired responsiveness to its physiological effects has been reported in many pathological situations including cardiovascular accidents. The aim of the present study was to evaluate the role of NO-dependent mechanisms on seasonal variation in aortic relaxation in vitro in rats. Male Sprague-Dawley rats grown up in different seasons in natural light/dark situation were used in the study, while the temperature and humidity were kept constant throughout the study (22+/-1 degrees C). The in vitro aortic ring responsiveness to an NO donor was studied in different seasons. Intact and denuded rings were pre-contracted with phenylephrine and vaso-relaxatory response to sodium isosorbide dinitrate (10(-8) to 10(-4)M) was recorded in vitro. The vaso-relaxatory response to isosorbide dinitrate (10(-6)M) was higher in aortic rings obtained in summer compared with those in winter and fall. There was a significant difference in EC(50) of sodium isosorbide dinitrate-induced vaso-relaxation of rings obtained from rats which were grown up in summer and winter (EC(50): 2.23+/-0.069 versus 4.31+/-0.088, P<0.05). The maximum response (R(max)) to isosorbide dinitrate was, however, identical in rings obtained from these rats. In conclusion, the in vitro responsiveness of aorta to NO is affected by seasonal light/dark periods the rats are exposed. This might be one of the reasons why more sudden cardiac deaths occur also in humans during winter.  相似文献   
88.
The present study portrays the effects of some elements, namely: iron, zinc, copper, magnesium and gold, on platelet count, PCV and platelet aggregation, 60 minutes following administration of the metal salts. Marked thrombocytopenia was encountered in rats treated with ferrous sulphate while the platelet count was significantly changed with the other elements tested. The PCV was significantly increased following treatment with ferrous sulphate and large dose of gold chloride, but was insignificantly altered with the other elements. As regards platelet aggregation, all metals tested, with the exception of magnesium caused significant inhibition of platelet aggregation was only significantly impaired following treatment with iron and gold, but was insignificantly altered following treatment with zinc and copper. On the other hand, treatment with magnesium resulted in enhancement of both ADP- and collagen-induced aggregation. The mechanisms underlying these effects are discussed.  相似文献   
89.
The in vitro effects of zinc and magnesium salts on blood coagulation mechanism and platelet aggregation were studied on rat plasma. Addition of zinc sulphate to pooled rat plasma in a range of concentrations (0.3-1 mg/ml) caused a dose dependent significant prolongation of recalcification, prothrombin and partial thromboplastin times. These effects reached a peak after 30 minutes while the thrombin clotting time was not significantly altered and was even shortened in the presence of highest concentration of zinc tested (1 mg/ml). Incubation of thrombin with zinc sulphate (150 micrograms/ml) for up to 30 minutes did not affect significantly the action of thrombin. Incubation of the same concentrations of zinc sulphate with fibrinogen produced non clotting of fibrinogen after 0-minutes. Addition of rising concentrations of zinc sulphate to rat PRP produced inhibition of ADP-induced platelet aggregation. On the other hand, collagen-induced aggregation was insignificantly inhibited in the presence of zinc. In contrast, in vitro additions of rising concentrations of magnesium sulphate (2-5 mg/ml) to pooled rat plasma exerted no effect on recalcification time immediately after addition (0-minutes), but after 5 minutes following incubation it produced significant shortening of recalcification time in all the doses tested. The prothrombin time showed a general trend of shortening, maximal after 5-minutes incubation. The results of partial thromboplastin times revealed clotting before addition of calcium chloride. The thromboplastin time also showed progressive shortening with rising concentrations of magnesium sulphate. When thrombin solution was exposed to magnesium sulphate (2.5 mg/ml) no effect on the activity of thrombin was seen for up to 30 minutes. Fibrinogen solution similarly exposed to the same concentration of magnesium sulphate did not show any significant effect on its clottability with thrombin for up to 30 minutes. Magnesium sulphate in the range of doses tested significantly enhanced platelet aggregation of PRP in response to both ADP and collagen, and the responses observed were not dose dependent. The mechanisms underlying the effects of these two metals on blood clotting and platelet aggregation are discussed.  相似文献   
90.
The sensitive ELISA assay was used to measure the specific rubella virus IgG & IgM, and also the total IgM in the umbilical cord sera taken from 182 Saudi mothers during delivery in the Maternity Department at Al Ali General Hospital, Riyadh, Saudi Arabia. Nearly 84.6% (154 out of 182) Saudi women tested were found to be immune to rubella virus.  相似文献   
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