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81.
Hepatic amino acid uptake, urea and glucose production are increased in acute uraemia. It has been shown that this metabolic pattern is mediated by glucocorticoids. Accordingly, the administration of the antiglucocorticoid RU 38486 to acutely uraemic rats resulted in a reduction of serum urea-N and glucose levels. To clarify whether this effect is due to a reduction in hepatic gluconeogenesis we examined the effect of the antiglucocorticoid RU 38486 on urea and glucose formation in isolated hepatocytes from sham-operated (SHAM) and bilaterally nephrectomized (BNX) rats receiving RU 38486 or the vehicle only. Hepatic glucose production in BNX rats was considerably increased from Na-pyruvate (+79%), alanine (+174%), glutamine (+158%), and serine (+87%) compared with SHAM animals. Concomitantly, hepatic urea formation was also enhanced from amino acid substrates in acutely uraemic rats. When uraemic animals were treated with RU 38486, glucose production from amino acids and Na-pyruvate was reduced to the range of SHAM animals or even lower. This effect could not be demonstrated in SHAM-operated controls. A comparable decrement in hepatic urea production was observed in BNX rats treated with the antiglucocorticoid. Thus, glucocorticoids appear to play a key role in the abnormal hepatic urea and glucose production of acutely uraemic rats.  相似文献   
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BACKGROUND: Limited information exists on home transfusion practices. STUDY DESIGN AND METHODS: In 1995, a survey requesting data for 1994 was sent to 1273 American Association of Blood Banks (AABB) institutional members and 113 non-AABB home health care agencies that provide out-of-hospital transfusions. RESULTS: Of 943 respondents, 102 provide blood to a home transfusion program, 37 provide blood and run a home transfusion program, and 13 run a home transfusion program only, for a total of 152 (16%) with some involvement in home blood transfusions. Most of the 50 respondents with a home transfusion program are licensed by their state and accredited by the Joint Commission on Accreditation of Healthcare Organizations. All respondents have written policies for home transfusion, and 90 percent require a signed informed-consent document before initiating transfusions in the home. Most have policies requiring that there be a second adult and a telephone in the home, that the home be deemed safe for transfusion, that the patient's physician be readily available, and that the patient have had prior transfusions. The most common component issued by the blood providers was red cells, followed by platelets. White cell-reduced components were always provided by 36 percent of respondents. The most common patient diagnosis was cancer. Home transfusions were provided primarily by registered nurses. Only 14 percent of respondents indicated that the medical director of the blood bank is responsible for approving a patient for home transfusion. A posttransfusion visit is performed by 46 percent of respondents. CONCLUSION: Although most facilities have policies for the administration of home transfusions, there remains marked heterogeneity among blood providers and transfusionists regarding home transfusion practices.  相似文献   
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SM Bromley  RL Doty 《Oral diseases》2010,16(3):221-232
Oral Diseases (2010) 16 , 221–232 Practitioners of oral medicine frequently encounter patients with complaints of taste disturbance. While some such complaints represent pathological processes specific to the gustatory system, per se, this is rarely the case. Unless taste‐bud mediated qualities such as sweet, sour, bitter, salty, umami, chalky, or metallic are involved, ‘taste’ dysfunction inevitably reflects damage to the sense of smell. Such ‘taste’ sensations as chicken, chocolate, coffee, raspberry, steak sauce, pizza, and hamburger are dependent upon stimulation of the olfactory receptors via the nasopharynx during deglutition. In this paper, we briefly review the anatomy, physiology, and pathophysiology of the olfactory system, along with means for clinically assessing its function. The prevalence, etiology, and nature of olfactory disorders commonly encountered in the dental clinic are addressed, along with approaches to therapy and patient management.  相似文献   
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Objective: To evaluate the impact of late 3rd trimester fetal growth cessation on anatomical birth characteristic predictions used in classifying SGA neonates.

Methods: A prospective longitudinal study was performed in 119 pregnancies with normal neonatal growth outcomes. Seven biometric parameters were measured at 3–4 weeks intervals using 3D ultrasonography. Rossavik size models were determined to predict birth characteristics at different ages. Percent Differences (% Diff) were calculated from predicted and measured birth characteristics. Growth Cessation Ages (GCA) were identified when no systematic change in % Diff values occurred after specified prediction ages. Systematic and random prediction errors were compared using different assumptions about the GCA. Predicted and measured size parameters were used to determine six new Growth Potential Realization Index (GPRI) reference ranges. Five were used to sub-classify 34 SGA neonates (weight?<?10th percentile) based on the number of abnormal GPRI values.

Results: Growth cessation ages were 38 weeks for HC, AC, mid-thigh circumference, estimated weight and mid-arm circumference. Crown-heel length GCA was 38.5 weeks. At GCA, birth characteristics had prediction errors that varied from 0.08?±?3.4% to 15.7?±?9.1% and zero % Diff slopes after 38 weeks. Assuming growth to delivery gave increased systematic and random prediction errors as well as positive % Diff slopes after 38 weeks, MA. Seventeen of the SGA neonates had 0 or 1 abnormal GPRI values [Subgroup 1] and 17 others had 2 or more abnormal values [Subgroup 2]. In Subgroup 1, 4/85 (4.7%) of GPRI's were abnormal while in Subgroup 2, 43/85 (50.6%) were abnormal. Use of only one type of GPRI for SGA subclassification resulted in substantial false negative and some false positive rates when compared to subclassification based on all five GPRI values.

Conclusions: Growth cessation occurred at approximately 38 weeks for all six birth characteristics studied. SGA neonates can be separated into normal and growth restricted subgroups based on the frequency of abnormal GPRI values (GPRI Profile Classification).  相似文献   

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Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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