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91.
Streeter  RR; Presant  CA; Reinhard  E 《Blood》1977,50(3):427-432
In order to determine the prognostic significance of thrombocytosis in idiopathic sideroblastic anemia, the clinical courses of 17 patients were reviewed. Six patients (36%) had thrombocytosis, and none developed acute leukemia. Nine patients (53%) had normal platelet counts, and one developed acute leukemia. Two patients (12%) were thrombocytopenic, and one died of acute leukemia. There was little correlation between survival and platelet count. Sixty-three additional case reports of idiopathic sideroblastic anemia were collected from the literature. Analysis of those patients and the patients in the present study documented transformation to acute leukemia in 5 of 9 (56%) thrombocytopenic patients, 4 of 54 (7.4%) patients with normal platelet counts, and 0 of 17 patients with thrombocytosis (p less than 0.05). Therefore patients with idiopathic sideroblastic anemia and thrombocytosis appear to have a decreased likelihood of leukemic transformation.  相似文献   
92.
Hypersensitivity pneumonitis: evaluation with CT   总被引:4,自引:0,他引:4  
Silver  SF; Muller  NL; Miller  RR; Lefcoe  MS 《Radiology》1989,173(2):441-445
Thirteen chest radiographs and computed tomographic (CT) scans obtained from 11 patients with hypersensitivity pneumonitis were reviewed. The CT findings were correlated with open lung biopsy findings in seven patients. The two patients with acute hypersensitivity pneumonitis showed air-space opacification on CT scans. An open lung biopsy, done in one of these patients, demonstrated noncaseating granulomas and filling of the air spaces with macrophages. The nine patients with subacute hypersensitivity pneumonitis showed small, rounded opacities and patchy air-space opacification on CT scans. These findings reflected the histologic findings, which consisted of interstitial pneumonitis, cellular bronchiolitis, and small, noncaseating granulomas. The six patients with symptoms for 12 months or longer also showed irregular linear opacities on CT scans, corresponding to areas of fibrosis. CT scans were superior to radiographs in helping to assess the type and extent of abnormalities, and high-resolution CT scans were superior to conventional CT scans.  相似文献   
93.

Background

Nasopharyngeal carcinoma (NPC) and other head and neck cancer (HNCA) types show a great epidemiological variation in different regions of the world. NPC has multifactorial etiology and many interacting risk factors are involved in NPC development mainly Epstein Barr virus (EBV). There is a need to scrutinize the complicated network of risk factors affecting NPC and how far they are different from that of other HNCA types.

Methods

122 HNCA patients and 100 control subjects were studied in the region of the Middle East. Three types of HNCA were involved in our study, NPC, carcinoma of larynx (CL), and hypopharyngeal carcinoma (HPC). The risk factors studied were the level of EBV serum IgG and IgA antibodies measured by ELISA, age, sex, smoking, alcohol intake, histology, and family history of the disease.

Results

EBV serum level of IgG and IgA antibodies was higher in NPC than CL, HPC, and control groups (p < 0.01). NPC was associated with lymphoepithelioma (LE) tumors, males, regular alcohol intake, and regular smoking while CL and HPC were not (p < 0.05). CL and HPC were associated with SCC tumors (p < 0.05). Furthermore, NPC, unlike CL and HPC groups, was not affected by the positive family history of HNCA (p > 0.05). The serum levels of EBV IgG and IgA antibodies were higher in LE tumors, regular smokers, younger patients, and negative family history groups of NPC patients than SCC tumors, non-regular smokers, older patients and positive family history groups respectively (p < 0.05) while this was not found in the regular alcoholics (p > 0.05).

Conclusion

It was concluded that risk factors of NPC deviate much from that of other HNCA. EBV, smoking, alcohol intake, LE tumors, male patient, and age > 54 years were hot risk factors of NPC while SCC and positive family history of the disease were not. Earlier incidence, smoking, LE tumors, and negative family history of the disease in NPC patients were associated much clearly with EBV. It is proposed that determining the correct risk factors of NPC is vital in assigning the correct risk groups of NPC which helps the early detection and screening of NPC.  相似文献   
94.
95.
Smoking prevalence among patients with posttraumatic stress disorder (PTSD) is over 40%. Baseline data from the VA Cooperative Studies Program trial of integrated versus usual care for smoking cessation in veterans with PTSD (N = 863) were used in multivariate analyses of PTSD and depression severity, and 4 measures of smoking intensity: cigarettes per day (CPD), Fagerström Test for Nicotine Dependence (FTND), time to first cigarette, and expired carbon monoxide. Multivariate regression analysis showed the following significant associations: CPD with race (B = ?7.16), age (B = 0.11), and emotional numbing (B =0 .16); FTND with race (B = ?0.94), education (B = ?0.34), emotional numbing (B = 0.04), significant distress (B = ?0.12), and PHQ‐9 (B = 0.04); time to first cigarette with education (B = 0.41), emotional numbing (B = ?0.03), significant distress (B = 0.09), and PHQ‐9 (B = ?0.03); and expired carbon monoxide with race (B = ?9.40). Findings suggest that among veterans with PTSD, White race and emotional numbing were most consistently related to increased smoking intensity and had more explanatory power than total PTSD symptom score. Results suggest specific PTSD symptom clusters are important to understanding smoking behavior in patients with PTSD.  相似文献   
96.
In studies of joint attention and sequences of interaction that foster joint attention, limited focus has been placed on toddler characteristics such as race, sex and socioeconomic status (SES). The purpose of the present study was to investigate the relationship between joint attention and toddler's race, sex and SES. Eighty-four dyads of diverse race, sex and SES were videotaped playing, and joint attention and initiating matemal bid sequences were coded. Joint attention related to a “persisting” mother, whether or not the toddler accepted the initial maternal bid. No race differences were found; however, females engaged in more frequent bouts of joint attention and had more frequent nonpersistent maternal responses after the bid was accepted. Finally, SES was generally unrelated to joint attention. The manner in which bids for joint attention transpired and the amount of joint attention that occurred was largely independent of the dyad's SES as measured here.  相似文献   
97.
98.
Combining exercise with calcium supplementation may produce additive or multiplicative effects at loaded sites; thus, we conducted a single blind, prospective, randomized controlled study in pre- and early-pubertal girls to test the following hypotheses. (1) At the loaded sites, exercise and calcium will produce greater benefits than exercise or calcium alone. (2) At non-loaded sites, exercise will have no benefit, whereas calcium with or without exercise will increase bone mass over that in exercise alone or no intervention. Sixty-six girls aged 8.8 +/- 0.1 years were randomly assigned to one of four study groups: moderate-impact exercise with or without calcium or low-impact exercise with or without calcium. All participants exercised for 20 minutes, three times a week and received Ca-fortified (434 +/- 19 mg/day) or non-fortified foods for 8.5 months. Analysis of covariance (ANCOVA) was used to determine interaction and main effects for exercise and calcium on bone mass after adjusting for baseline bone mineral content and growth in limb lengths. An exercise-calcium interaction was detected at the femur (7.1%, p < 0.05). In contrast, there was no exercise-calcium interaction detected at the tibia-fibula; however, there was a main effect of exercise: bone mineral content increased 3% more in the exercise than non-exercise groups (p < 0.05). Bone mineral content increased 2-4% more in the calcium-supplemented groups than the non-supplemented groups at the humerus (12.0% vs. 9.8%, respectively, p < 0.09) and radius-ulna (12.6% vs. 8.6%, respectively, p < 0.01). In conclusion, greater gains in bone mass at loaded sites may be achieved when short bouts of moderate exercise are combined with increased dietary calcium, the former conferring region-specific effects and the latter producing generalized effects.  相似文献   
99.
100.
Audits of clinical transfusion practice have consistently demonstrated deficiencies in knowledge and practice that impact on patient safety and in some cases result in death. These deficiencies include transfusion being prescribed inappropriately, administration of blood components using poor processes, documentation deficiencies and inadequate identification of potential transfusion recipients. Improvement needs to be driven by a multifaceted approach that includes robust systems and mechanisms to ensure compliance combined with education of staff. However, education of medical, nursing and other staff involved in the transfusion chain can be difficult. Large numbers of staff, shiftwork, varying levels of background knowledge and limited resources create significant challenges. Consideration of these problems and informal needs analysis defined a web‐based or on‐line learning tool (e‐learning) as being a suitable mechanism to assist hospitals to increase knowledge of staff. An effective e‐learning tool must be engaging, replicate an authentic learning environment, cater for various learning styles and engage the learner in the learning process. This requires knowledge of on‐line learning best‐practice, learner profiles, learning styles and the learning environment, as well as consideration of interface design, motivational tools and knowledge retention strategies. Funding was provided by the South Australian Department of Health, under the BloodSafe programme, to develop an e‐learning tool. This has resulted in a multimedia‐rich programme utilizing video, audio, animations, and case studies and didactic instruction in order to create an authentic learning environment. Learning content includes expert and peer education, case studies, interactive games and puzzles and modelling of best‐practice processes. A flexible learning pathway gives learners control over learning sequence, content viewed and assessment. Learner demographics, progress and assessment tools and records are stored in an SQL database. This tool is available for use by hospitals and healthcare institutions and professionals. Initial use has demonstrated a high degree of acceptance with participants providing strong feedback on the content, learning pathway and ease of use. Further development is being undertaken to add additional modules offering advanced content and/or a broader audience base. The initial implementation of this e‐learning tool is directed at an Australian audience, however, the content is relevant to the wider transfusion scene in the Asia‐Pacific region (and beyond) as a mechanism for educating staff involved in all steps of the transfusion chain.  相似文献   
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