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341.
Renal function of workers with low-level cadmium exposure   总被引:7,自引:0,他引:7  
The influence of occupational exposure to cadmium on renal function was examined in 27 male cadmium workers from plants with second-degree usage of cadmium. The levels of cadmium in the blood and urine and various protein concentrations in the urine and serum were determined. The urinary levels of beta 2-microglobulin, retinol-binding protein, and N-acetyl-beta-D-glucosaminidase were statistically significantly increased in workers with urinary cadmium levels above 50 nmol/l. SDS-PAGE electrophoresis with silver staining is probably a sensitive indicator of the early effects of cadmium on protein excretion. The currently recommended biological exposure limits may have to be lowered.  相似文献   
342.
The objective is to investigate the effect of obesity and hepatosteatosis on the Doppler waveform pattern of the hepatic veins. B-mode and duplex Doppler sonography of the liver and the right hepatic vein was performed in 102 obese subjects and 84 healthy volunteers. The severity of fatty infiltration was graded as mild, moderate and severe. The flow pattern of the right hepatic vein was classified as triphasic, biphasic and monophasic. The Doppler flow pattern in the right hepatic vein was triphasic in 56 (55%), biphasic in 27 (26%) and monophasic in 19 (19%) obese patients, whereas it was triphasic in 83 (99%) and biphasic in 1 (1%) control subject, achieving a statistical significance (Mann-Whitney U-test, P<0.001). There was an inverse correlation between the sonographic grade of the hepatosteatosis and the phasicity of hepatic venous flow (r=–0.67, P<0.001). The hepatic vein pulsatility is significantly dampened in obese patients correlating with the grade of hepatosteatosis. The body habitus itself does not have an independent effect on hepatic venous waveform. The alteration in hepatic vein Doppler flow pattern in an obese population may suggest reduced vascular compliance in the liver because of fatty infiltration.This revised version was published online in October 2004 with corrections to the author names. The authors are: Nevzat Karabulut, Selçuk Kazil, Baki Yagci, Nuran Sabir.  相似文献   
343.
Effects of powdered Fagonia cretica plant and its two major triterpenoid saponins (saponin-I and saponin-II), isolated from its ethanolic extract, on red blood cells (RBC) count, haemoglobin concentration (HC), mean corpuscular haemoglobin (MCH) and on total leucocyte (WBC) count of normal male rabbits were investigated. Saponins treated three dose groups of animals indicated significant decrease in RBC count during the experimental period of 16 days. This effect was more pronounced in animals treated with saponin-II than saponin-I. The 0.50 and 1.0g crude drug treated animals and 10 and 20mg of both the saponins treated animals, indicated a decreasing tendency of HC up to the 4th day, which increased afterwards up to the 16th day. The third dose of these materials (1.50g of crude drug and 30mg of both saponins) exhibited a highly significant decreasing pattern, up the 16 days. The decreasing effect of haemoglobin concentration was more distinct in the saponin-II treated animals than saponin-I and the crude drug. The MCH followed a reverse pattern than RBC and HC. A continued decreasing trend was found in total WBC during the 16 days treatment. An amount of 1.50g of the crude drug and 30mg of both the saponins had highly significant decreasing effects on the amount of total leukocyte count of rabbit's blood.  相似文献   
344.
Hydatid disease, although known to occur in most body areas, is extremely rare in the female reproductive system. There are different modes of presentation for the disease; however, we report and discuss a case presented with cystic vesicles passing through the vagina, which is considered as a rare presentation for secondary involvement of the uterus and both ovaries. We confirmed diagnosis with radiological examinations and serological tests. We operated on the patient, and studied the excised cysts microscopically. The gynecologist should be aware of hydatid cyst when vaginally passing a grape like vesicle is presented by the patient.  相似文献   
345.
Objective: The methods and results are described of a study on the dermal absorption of chlorpyrifos (CPF) in humans established via urinary excretion of the metabolite 3,5,6-trichloro-2-pyridinol (TCP). Methods: Two dermal, single, doses of CPF were applied in two study groups (A and B) each comprising three apparently healthy male volunteers who gave their written informed consent. The clinical part of the study was conducted in compliance with the ICH Guideline and the EC principles of good clinical practice (GCP). An approximately 0.5 ml dilution of CPF in ethanol was applied to an area of ~100 cm2 of the volar aspect of the forearm, resulting in doses of either 5 mg (A) or 15 mg (B) of CPF per study subject. Duration of dermal exposure was 4 h, after which the non-absorbed fraction was washed off. The following samples were collected at pre-determined intervals for the determination of either CPF or its metabolite TCP: dosing solutions, wash-off fractions and urine samples collected up to 120 h after dosing. Results: A relatively large fraction of CPF (42%–67% of the applied dose) was washed off from the exposed skin area. Application of either 5 mg (A) or 15 mg CPF (B) resulted in the total urinary excretion of 131.8 g (A) or 115.6 g (B) of TCP 120 h after dosing. This indicated that 4.3% of the applied dose has been absorbed (A), while in group (B) no significant increase in urinary TCP (115.6 g) was established. The latter indicates that an increase in the dermal dose at a fixed area does not increase absorption, which suggests that the percutaneous penetration rate was constant. Further, it was observed that the clearance of CPF by the body was not completed within 120 h, suggesting that CPF or TCP was retained by the skin and/or accumulated in the body. A mean elimination half-life of 41 h was established. Conclusion: The results show that daily occupational exposure to CPF may result in accumulation of CPF and/or its metabolites, possibly resulting in adverse effects.  相似文献   
346.
347.
Are Daughters More at Risk Than Sons in Some Societies?   总被引:2,自引:0,他引:2  
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348.
349.
BackgroundThe outcome of cementless total knee arthroplasty (TKA) relies on successful bony ingrowth into the implant surfaces. Failures due to aseptic loosening are still reported, especially in younger and more active patients. The objective of this study is to quantify the micromotion of a commercially available design of cementless tibial tray under loading conditions simulating walking and stair descent.MethodA commercially available design of cementless total knee arthroplasty was implanted in 7 cadaveric knees which were preconditioned with 500 cycles of 0°-100° flexion under a vertical load of 1050 N in a custom-built, multiaxial functional activity simulator. This was followed by application of the peak forces and moments occurring during walking and stair descent. During each loading procedure, 3-dimensional motion at the bone-prosthesis interface was measured using digital image correlation.ResultsThe tray migrated 101 ± 25 μm on average during preconditioning, which was dominated by rotation in the sagittal plane (92% of total migration), combined with posterior translation (28%) and minimal rotation in the transverse plane (14%). The migration varied 2.7-fold (61-167 μm) between the 6 measurement zones. Stair descent produced significantly higher total micromotion than walking in zone #5 (62 ± 9 vs 51 ± 10 μm, P < .05) and zone #6 (68 ± 17 vs 37 ± 10 μm, P < .05). In addition, during stair descent, the tray exhibited significantly more tilting (anterior zones: 31 ± 17 vs ?16 ± 20 μm, P < .05; posterior zones: ?60 ± 8 vs ?40 ± 7 μm, P < .05) and more anteroposterior displacement in the anterior zones (?25 ± 3 vs ?13 ± 2 μm, P < .05) when compared to walking.ConclusionThe relative motion at the bone-prosthesis interface varied substantially around the periphery of the cementless tray. Under the loading conditions evaluated, the tray primarily underwent a rocking motion in the sagittal plane. Compared with walking, stair descent produced significantly more micromotion, especially in the posterior zones.  相似文献   
350.
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