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71.
The Japan Clinical Oncology Group conducted two multicenter phase II trials in 200 patients with advanced Hodgkin lymphoma (HL) in the 1990s. Among 181 patients whose histopathological specimens were available and reviewed by 6 hematopathologists, 167 (92.3%) were diagnosed with HL. Five-year overall survival (OS) among these 167 patients was 88.3%, including 89.2% among nodular sclerosis and 82.2% among mixed cellularity cases. International prognostic score was not closely associated with OS. Seven unfavorable prognostic factors for OS on univariate analysis were male, B symptoms, clinical stage of III or IV, elevated serum LDH, elevated alkaline phosphatase, elevated β2-microglobulin, and pathological subtype (mixed cellularity and lymphocyte depletion). On multivariate analysis, male [HR 3.30 (95% CI 1.15–9.52, p = 0.027)] and elevated serum LDH [HR 2.41 (95% CI 1.07–5.43, p = 0.034)] were independent factors for OS. Based on these prognostic factors, the 5-year OS was 95.7% in the low-risk group (no adverse factor), 87.9% in the intermediate-risk group (1 adverse factor) and 73.3% in the high-risk group (2 adverse factors). This simple prognostic model for HL warrants further validation studies.  相似文献   
72.
Several DNA probes were designed for use in real-time polymerase chain reaction (PCR) assays to target sequence variation within the ribosomal intergenic spacer (IGS) of schistosomes. A sub-section of the IGS (∼300 bp) was amplified, with cross-specific primers, after which group-specific fluorescent, locked nucleic acid probes were assessed for their ability to differentiate and quantify DNA from Schistosoma haematobium and Schistosoma mansoni group parasites. A number of fluorescent probe candidates were screened and validated against genomic DNA from adult schistosome worms and laboratory infected freshwater snails. Two fluorescent, locked nucleic acid probes ShaemLNA5 and SmanLNA2, of 20–26 bp in length, were identified and found to be effective in providing evidence of infection in field-collected snails. To adapt these real-time PCR assays for more resource-poor laboratory settings, a PCR-restriction fragment length polymorphism (RFLP) assay was developed and primer/probe combinations were modified for use in oligochromatography, a DNA ‘dipstick’ technology. An appropriate dipstick was developed, inclusive of internal amplification and amplicon migration controls that could be of particular importance for assessing schistosome transmission dynamics. These assays and tools also have future potential for use in detection of schistosome infections in humans and livestock.  相似文献   
73.
Objective  To assess the efficacy of intermittent preventive treatment (IPT) against malaria in school-aged children.
Methods  This was an open randomized controlled trial of seasonal IPT among school children (IPTsc) aged 6–13 years in Kollé, Mali. The study began in September 2007 and completed follow-up in May 2008. Students were randomized to one of three study arms: Sulfadoxine–pyrimethamine plus artesunate (SP/AS), amodiaquine plus artesunate (AQ/AS) or vitamin C. All students received two full treatment doses, given 2 months apart during the season of high transmission from September to December. Groups were compared with respect to incidence of clinical malaria, asymptomatic parasitemia and haemoglobin concentration.
Results  A total of 296 students were randomized, and retention in the study was 99.3%. Clinical malaria incidence in the SP/AS and AQ/AS arms was reduced by 66.6% and 46.5%, respectively, vs . vitamin C ( P  < 0.001). There were fewer clinic visits for any cause among the children receiving SP/AS or AQ/AS ( P  = 0.024). The prevalence of asymptomatic parasitemia was fivefold higher in the vitamin C arm than either SP/AS or AQ/AS at each post-treatment evaluation ( P  < 0.001). At the end of the transmission period, children treated with IPT had lower rates of anaemia (SP/AS, 17.7%; AQ/AS, 16.0%; vitamin C, 29.6%; P  = 0.039).
Conclusion  IPT among school children reduced the rates of clinical malaria, all-cause acute clinic visits, asymptomatic parasitemia and anaemia among school-aged children.  相似文献   
74.
BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships.  相似文献   
75.
76.
The eight member states (Djibouti, Eritrea, Ethiopia, Kenya, Somalia, South Sudan, Sudan and Uganda) of the Intergovernmental Authority for Development (IGAD) have the largest proportions of cross-border mobile pastoralists and refugees in Africa. Although all IGAD countries have had national HIV/AIDS prevention, care and treatment programmes since the late 1980s, the IGAD Regional HIV & AIDS Partnership Program was (IRAPP) established in 2007 to mitigate the challenges of HIV among neglected pastoral and refugee communities. This article assesses vulnerability of pastoralists and refugee communities to HIV and interventions targeting these groups in the IGAD countries. Outcomes from this study may serve as a baseline for further research and to improve interventions. Published articles were accessed through web searches using PubMed and Google Scholar engines and unpublished documents were collected manually. The search terms were HIV risk behaviour, vulnerability, HIV prevalence and interventions, under the headings pastoralists, refugees, IGAD and north-east Africa for the period 2001–2014. Of the 214 documents reviewed, 78 met the inclusion criteria and were included. Most HIV/AIDS related studies focusing of pastoral communities in IGAD countries were found to be limited in scope and coverage but reveal precarious situations. Sero-prevalence among various pastoral populations ranged from 1% to 21% in Ethiopia, Kenya, Somalia and Uganda and from 1% to 5% among refugees in Sudan, Kenya and Uganda. Socioeconomic, cultural, logistic, infrastructure and programmatic factors were found to contribute to continuing vulnerability to HIV. Interventions need to be further contextualised to the needs of those impoverished populations and integrated into national HIV/AIDS programmes. HIV/AIDS remains a major public health concern among the pastoral and refugee communities of IGAD countries. This calls for IGAD to collaborate with national and international partners in designing and implementing more effective prevention and control programmes. Furthermore, interventions must extend beyond the health sector and improve the livelihood of these populations.  相似文献   
77.
78.
We assessed morbidity indicators for both Schistosoma haematobium and Schistosoma mansoni infections and evaluated the appropriateness of the World Health Organization (WHO) guidelines for ultrasound in schistosomiasis in the context of large-scale control interventions. Abdominal and urinary tract ultrasonography was performed on 2,247 and 2,822 school children, respectively, from 29 randomly selected schools in Mali before the implementation of mass anthelminthic drug administration. Using two-level logistic regression models, we examined associations of potential factors with the risk of having a positive ultrasound global score (morbidity indicative of S. haematobium infection), abnormal image pattern scores, dilatation of the portal vein, and/or enlarged liver (morbidity indicative of S. mansoni infection). The WHO protocol was found useful for detection of S. haematobium pathology but overestimated the risk of portal vein dilatation and left liver lobe enlargement associated with S. mansoni infection. We conclude that ultrasonography should be included in large-scale control interventions, where logistics allow, but cautiously.  相似文献   
79.
Human African trypanosomiasis, or sleeping sickness caused by Trypanosoma brucei gambiense, occurs in Western and Central Africa. T. brucei s.l. displays a huge diversity of adaptations and host specificities, and questions about its reproductive mode, dispersal abilities, and effective size remain under debate. We have investigated genetic variation at 8 microsatellite loci of T. b. gambiense strains isolated from human African trypanosomiasis patients in the Ivory Coast and Guinea, with the aim of knowing how genetic information was partitioned within and between individuals in both temporal and spatial scales. The results indicate that (i) migration of T. b. gambiense group 1 strains does not occur at the scale of West Africa, and that even at a finer scale (e.g., within Guinea) migration is restricted; (ii) effective population sizes of trypanosomes, as reflected by infected hosts, are probably higher than what the epidemiological surveys suggest; and (iii) T. b. gambiense group 1 is most likely a strictly clonally reproducing organism.  相似文献   
80.
In this prospective study, we have compared women undergoing laparoscopic cholecystectomy, laparoscopic gynaecological surgery and laparoscopic minor gynaecological procedures (diagnostic, tubal, ligation) (n = 10 in each group) to determine if lower abdominal laparoscopy results in less postoperative pulmonary dysfunction than upper abdominal laparoscopy. Pulmonary testing was performed before operation, and 3 and 6 h after operation, on the first and second days after surgery. After operation, a significant reduction in forced vital capacity, forced expiratory volume in 1 s and peak expiratory flow rate occurred after laparoscopic cholecystectomy at each time. There were no significant changes after minor gynaecologic laparoscopy, whereas laparoscopic gynaecological surgery resulted in minor pulmonary dysfunction on the day of surgery only. We conclude that postoperative pulmonary function was less impaired after gynaecological laparoscopy than after laparoscopic cholecystectomy. This study suggests that the site of surgery is an important determinant of lung dysfunction after laparoscopy.   相似文献   
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