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21.
Contribution of a case report of cutaneous horn of penis surgically treated with extensive resection of the implantation base. A well differentiated, microinvasive epidermoid carcinoma was histopathologically demonstrated on a hyperkeratosis squamous papilloma. Although underlying lesions to cutaneous horn are usually benign, malignant changes have been reported in up to one third of cases; surgical treatment should therefore include extensive resection of the implantation base.  相似文献   
22.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective.  相似文献   
23.
This research demonstrates the use of biogenic silica derived from bamboo leaf ash as a support for iron oxide nanoparticles. The preparation includes silica extraction from bamboo leaf ash and iron oxide nanoparticle impregnation into the silica gel under hydrothermal conditions, which is followed by calcination at 400 °C for 2 h. The physicochemical characterization includes X-ray diffraction analysis, gas sorption analysis, scanning electron microscopic analysis and transmission electron microscopic analysis. The light absorption capability and the band gap energy of the materials were determined by diffuse-reflectance UV–visible spectrophotometry. The materials obtained by varying the Fe content to 5 and 10% wt. were evaluated in rhodamine B photocatalytic degradation and photooxidation systems. It was found that the materials have a combined hematite and magnetite nanostructure, with the ratio of 9:10, and the particle sizes range from 10 to 40 nm. With a band gap energy of 2.27 eV, the prepared materials produce the successive photocatalytic degradation of rhodamine B. It was clarified that the formation of composite enhances stability and reusability of photocatalyst as shown by the stable initial rate at wide pH range and reuse for 5 cycles. Degradation mechanism is enhanced by the addition of H2O2 as an oxidant, and the investigation of the effect of scavengers shows that the degradation rate not only depends on radical formation but also on other species related to the formation of oxidizing agent.  相似文献   
24.
The fungicide, methoxyethylmercury chloride, was given in a saline solution to four groups of Sprague-Dawley C D rats (5 , 5 ) as a single injection (IP) of 0, 0.5, 1.0, and 2.0 mg Hg/kg. In a three-day period, no changes were observed in urine collected every 24 h from rats given 0 or 0.5 mg Hg/kg; 1 mg Hg/kg induced only a transient increase of urine gamma glutamyl transferase (x 4) and alkaline phosphatase (x 2.5) on the day 2; 2.0 mg Hg/kg caused an early increase of enzymuria (day 1 and day 2) and a decrease of Na+, Cl, K+, urea, and creatinin excretion. Urine enzymes and total mercury excretion were higher in males. These time-related variations of enzymuria, compared to previous results with Hg Cl2, could reflect the existence of metabolites more toxic than the native compound.  相似文献   
25.
Kniep  B; Flegel  WA; Northoff  H; Rieber  EP 《Blood》1993,82(6):1776-1786
Monoclonal CDw60 antibodies recognize glycolipid antigens with restricted surface expression on human leukocytes. They allow us to define new functional subpopulations of T lymphocytes and are able to induce costimulatory signals. In this report, we describe the molecular composition of CDw60 glycolipid antigens derived from different human leukocyte subpopulations. The glycolipids were isolated and their structures were identified by immunochemical methods. All molecules containing the CDw60 determinant were found in the disialoganglioside fraction. They were O-acetylated derivatives of the gangliosides II3 (Neu5Ac)2-LacCer (GD3), IV3 (Neu5Ac)2-nLc4Cer (DSPG), and VI3 (Neu5Ac)2- nLc6Cer (DSnHC), respectively. The most common CDw60 glycolipid antigen in human leukocytes was 9-O-acetyl GD3. In a comparison of various cell types, the highest concentration of 9-O-acetyl GD3 on a per cell basis was determined in granulocytes and in blood T lymphocytes, whereas B lymphocytes, thymus cells, and monocytes contained considerably smaller amounts of this molecule. Polar CDw60 antigens such as 9-O-acetyl DSPG and 9-O-acetyl DSnHC were only detected in granulocytes.  相似文献   
26.
OBJECTIVE: Previous studies have demonstrated that losartan can block the thromboxane A2 receptor on the vascular wall. The aim of the present study was to assess the effect of losartan on human platelet activation. METHODS: Platelets were obtained from 15 healthy men, aged 26-40 years. Platelet activation was measured by changes in the light transmission of platelet-rich plasma stimulated by the thromboxane A2 analog U46619 (5 x 10(-6) mol/l) or ADP (10(-5) mol/l). RESULTS: U46619-stimulated platelet aggregation was significantly inhibited by losartan in a dose-dependent manner. Only a high dose of EXP 3174 (5 x 10(-5) mol/l), the in vivo active metabolite of losartan, was able to attenuate U46619-induced platelet activation. Captopril, an angiotensin I converting inhibitor, failed to modify U46619-induced platelet aggregation. Furthermore, the binding of [3H]-U46619 to platelets was competitively inhibited by losartan, whereas only a high dose of EXP 3174 reduced the binding of [3H]-U46619. Captopril failed to modify the binding of [3H]-U46619 to platelets. Losartan also reduced the platelet activation induced by ADP (10(-5) mol/l), a platelet agonist partially dependent on thromboxane A2. In addition, when thromboxane A2 generation was blocked by aspirin, ADP-induced platelet aggregation was inhibited to a similar degree to the inhibition induced by losartan. Exogenous angiotensin II did not elicit any modification of either U46619- or ADP-stimulated platelet aggregation. CONCLUSIONS: Losartan decreased platelet aggregation by a thromboxane A2-dependent mechanism. EXP 3174 was less potent than losartan in reducing thromboxane A2-dependent platelet activation. Captopril and exogenous angiotensin II had no effect on human platelet activation. These results suggest that losartan reduced thromboxane A2-dependent platelet activation independently of its effect on angiotensin II.  相似文献   
27.
Phospholipase A2 levels in acute chest syndrome of sickle cell disease   总被引:4,自引:2,他引:4  
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS.  相似文献   
28.
29.
BACKGROUND AND AIM OF THE STUDY: The study aim was to determine whether beta-blocker treatment (atenolol) improves cardiopulmonary exercise performance and ventilatory response in patients with mitral stenosis in sinus rhythm. METHODS: A prospective study comparing the results of cardiopulmonary exercise tests (CPETs) was performed before and after atenolol therapy in 17 patients in NYHA classes I and II with mitral stenosis in sinus rhythm. Transthoracic echocardiography was performed pre-study, and left ventricular diameters, ejection fraction and mitral valve area monitored. CPETs (Naughton protocol) were performed by two different investigators before and after one-week atenolol therapy (50 mg/day). The second investigator was blinded to the result of the baseline test. O2 consumption, CO2 production, ventilatory parameters and respiratory exchange ratios were measured on line. RESULTS: Maximal O2 uptake (VO2max) did not differ significantly before and after beta-blockade (median 16.8 and 15.0 ml/kg/min, respectively. Median heart rate at rest (72 versus 55 beats/min; p = 0.0003) and during peak exercise (153 versus 105 beats/min; p = 0.0003), and anaerobic threshold (10 versus 8.9 ml/kg/min; p = 0.02) were lower with beta-blockade compared with the baseline state. Minute ventilation at maximum exercise (41 versus 40 l/min) and ventilatory equivalent for CO2 (34 versus 35) were unchanged with atenolol therapy, indicating no improvement in ventilatory performance. When patients were grouped into those in whom VO2max was improved with atenolol therapy (n = 7) and those in whom it was impaired (n = 10), there were no inter-group differences with respect to age, left ventricular function, severity of mitral stenosis, NYHA class and grade of beta-blockade reached. Four patients felt symptomatically worse during atenolol treatment (lower NYHA functional class). CONCLUSION: Beta-blockade does not improve exercise tolerance in patients with mitral stenosis in sinus rhythm. In addition, ventilatory performance does not change with treatment.  相似文献   
30.
We present a case of Gitelman's Syndrome in a 20 year-old woman who came to our service with weakness, asthenia, leg cramps and tetany. Laboratory studies revealed metabolic alkalosis with hypokalemia, hypomagnesemia and low calcium in a 24-hour urine test. The diagnosis of this syndrome is made in some cases during adult life because this syndrome is asymptomatic over several years. Gitelman's Syndrome is autosomal recessive as is Bartter's Syndrome. The gene is located in chromosome 16q, which encodes the cotransporter Na/Cl sensitive to thiazide in the distal convoluted tubule. The defect of cotransporter produces an alteration of sodium reabsorption that causes electrolytic disorders typical of this Syndrome and different from Bartter's Syndrome. The typical electrolytic alterations are hypocalciuria and hypomagnesemia secondary to high urinary magnesium excretion. The prognosis of this syndrome is excellent and treatment consists in correction of serum electrolytes with oral administration of magnesium and potassium. In spite of this treatment, in some cases it is very difficult to reach normal serum levels of magnesium because of the high doses of oral magnesium, which produce common crises of diarrhea that increase magnesium gastrointestinal losses.  相似文献   
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