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1.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
2.
BACKGROUND: Repairing dorsal nasal defects is a frequent challenge for dermatologic surgeons, mainly due to the high frequency of basal cell carcinomas on this site. Obvious scars, mismatched skin and distortion of the nasal contour are the surgical hazards that must be avoided in these cases. AIM: Our aim was to perform surgery involving a simple flap in order to repair medium to large defects on the dorsal side of the nose. METHODS: The dorsal horizontal advancement flap was studied in 12 patients, in order to evaluate the benefits and limits of this surgical procedure. RESULTS: The resulting scars on most of our patients were well-camouflaged among their natural skin lines, and there was neither distortion of the alar contour nor the nostril. CONCLUSIONS: This flap is easy to perform and, in selected cases, provides an outstanding alternative to second-intention healing, full-thickness skin grafts, transposition, rotation and pedicle flaps.  相似文献   
3.
Coating and doping with zinc have been used to modify LiNi0.5Mn1.5O4 powders prepared at 700 and 800 °C. As previously found in the literature, surface treatment with zinc leads to a net improvement of the electrochemical performance of the 5-V electrode in lithium cells. X-ray diffraction reveals the occurrence of surface ZnO, which disappears after heating at 500 °C. This indicates that ZnO forms a coating, although zinc can also be incorporated in the LiNi0.5Mn1.5O4 framework. The electrochemical oxidation of both bare LiNi0.5Mn1.5O4 and zinc treated products has been followed by ex situ X-ray diffraction of charged electrodes. For both materials a decrease in the cubic unit cell parameter and the formation of two cubic phases during lithium extraction has been found. Lattice contraction is significantly larger in the sample modified with zinc. EIS measurements give direct evidence of the better stabilization of the electrode surface in the coated material.  相似文献   
4.
BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55)  相似文献   
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BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
8.
Purpose. The objective of this study was to determine the relationship between muscular strength and bone mineral density (BMD) in patients undergoing regular haemodialysis. Methods. The BMD was measured in the lumbar spine (L2L4) and in the proximal femur (femoral neck and trochanter) with dual-energy X-ray absorptiometry (DEXA (Lunar DPX). Muscular strength of the extensors, flexors and abductors muscles of the femur (proximal muscles) and extensors muscles of the back was measured with an isometric cynamometer. Thirty patients, 15 women with a mean age of 33.7 years (18-43) and 15 men with a mean age of 15.5 years (18-65) were included in the study. Results. There was a positive and significant correlation between the BMD of the femoral neck and muscular strength of the flexors (r=0.490, P<0.005), the extensors (r=0.658, P<0.01) and the abductors muscles of the femur (r=0.671, P <0.0008), as well as between the muscular strength of the flexors (r=0.413, P <0.02) and extensors muscles of the femur (r=0.433, P <0.01) with BMD of the trochanter. There was no correlation between the muscular strength of the back extensor muscles and the BMD of the lumbar spine (r=-0.119, P NS). There was no correlation between the BMD and the number of years of haemodialysis therapy (r=-0.032, P NS), the patient's age (r=-159, P NS), or the value of serum PTH (r=0.369, P NS) respectively. However, there was a significant correlation between the BMD of the femoral neck with muscular strength (r=0.602, P <0.05). Conclusion. This study reveals the close relationship that exists between muscular strength of the proximal muscles and the BMD of proximal femur in patients undergoing haemodialysis.  相似文献   
9.
Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
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