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231.
232.
A prospective study was performed to determine the prevalence of endocervical infection by Chlamydia trachomatis and vaginal colonization by Mycoplasma hominis and Ureaplasma urealyticum in pregnant women seeking routine obstetrical care in two clinics in the southern part of the Netherlands. C. trachomatis was detected using the direct immunofluorescence staining technique. For the genital mycoplasmata, generally accepted culture methods were used. Evaluable samples were obtained from 691 of 770 women in the first trimester of pregnancy. C. trachomatis was detected in 2.3%, M. hominis in 5.2% and U. urealyticum in 23.9% of the women. The isolation percentages of C. trachomatis and U. urealyticum were almost equally distributed in the different age groups. The prevalence of all three micro-organisms did not seem to be related to parity. Smoking and alcohol consumption seemed to influence the isolation rate of M. hominis and U. urealyticum.  相似文献   
233.
We examined the expression of CD81 (also known as TAPA, or target of the antiproliferative antibody) after traumatic spinal cord injury in the rat. CD81, a member of the tetraspanin family of proteins, is thought to be involved in reactive gliosis. This is based on the antiproliferative and antiadhesive effects of antibodies against CD81 on cultured astrocytes, as well as its up-regulation after penetrating brain injury. CD81 expression following dorsal hemisection of the spinal cord was determined immunohistochemically at time points ranging from 1 day to 2 months postlesion (p.l.). In the unlesioned cord a low background level of CD81 was observed, with the exception of the ependyma of the central canal and the pia mater, which were strongly CD81-positive. One day p.l., CD81 was diffusely up-regulated in the spinal cord parenchyma surrounding the lesion site. From 3 days onward, intensely CD81-positive round cells entered the lesion site, completely filling it by 7 days p.l. Staining with the microglial markers OX-42 and Iba1 revealed that these cells were reactive microglia/macrophages. At this time, no significant CD81 expression by GFAP-positive reactive astrocytes was noted. From the second week onward, CD81 was gradually down-regulated; i.e., its spatial distribution became more restricted. The CD81-positive microglia/macrophages disappeared from the lesion site, leaving behind large cavities. After 2 months, astrocytes that formed the wall of these cavities were strongly CD81-positive. In addition, CD81 was present on reactive astrocytes in the dorsal funiculus distal from the lesion in degenerated white matter tracts. In conclusion, the spatiotemporal expression pattern of CD81 by reactive microglia and astrocytes indicates that CD81 is involved in the glial response to spinal cord injury.  相似文献   
234.
235.
Influence of population density on antibiotic resistance   总被引:4,自引:0,他引:4  
Antibiotic consumption and population density as a measure of crowding in the community were related to the prevalence of antibiotic resistance of three cities in three different countries: St Johns in Newfoundland (Canada), Athens in Greece and Groningen in The Netherlands. Antibiotic consumption was expressed in DDD (defined daily dose), as DID (DDD/1000 inhabitants/day) and as DSD (DDD/km(2)). The prevalence of antibiotic-resistant Escherichia coli and enterococci was determined in faecal samples of healthy volunteers. In both Newfoundland (28 DID) and Greece (29 DID) the overall consumption of antibiotics was more than three times higher compared with that of The Netherlands (9 DID). The lowest prevalence of resistant E. coli against the majority of antibiotics tested was found for the samples from Newfoundland and was significant (P < 0.05) for cefazolin, oxytetracycline and trimethoprim. A poor correlation between the number of DID and the prevalence of resistance was observed [the Pearson correlation coefficient (Pcc) ranged between -0.93 and 0.87]. However, when population density was taken into consideration and antibiotic consumption was expressed in DSD, a strong correlation was observed (and Pcc ranged between 0.86 and 1.00). This study suggests that population density is an important factor in the development of antibiotic resistance and warrants special attention as a factor in resistance epidemiology.  相似文献   
236.
The prevalence and degree of antibiotic resistance in catfish and eel farms in the southern part of The Netherlands was examined using motile aeromonads as indicator bacteria. A total of 29 water samples were collected, originating from six catfish farms, one catfish hatchery and three eel farms, and were plated on an Aeromonas-selective agar with and without antibiotics. From each plate, one colony was screened for presumptive motile aeromonads and tested for antibiotic susceptibility. The prevalence of resistance was as follows: ampicillin and oxytetracycline 100%; sulfamethoxazole 24%; trimethoprim 3%; and ciprofloxacin and chloramphenicol 0%. The majority of samples showed a high degree of oxytetracycline resistance, implicating fish farms as a major reservoir of oxytetracycline resistance genes. This reservoir might form a risk for human health and has major consequences for the effectiveness of this antibiotic in the treatment of infectious diseases in fish.  相似文献   
237.
OBJECTIVES: To determine the prevalence of antibiotic-resistant faecal Escherichia coli from adult volunteers from urban (U) areas in Kenya, Mexico, Peru and the Philippines, and non-urban (NU) locations in Curacao, Mexico, Venezuela, Ghana, Zimbabwe and the Philippines. METHODS: Faecal samples of adult volunteers (n=1290) were analysed in one laboratory for the presence of antimicrobial-resistant E. coli using Eosin Methylene Blue agar plates containing, respectively, ampicillin, oxytetracycline, cefazolin, ciprofloxacin, gentamicin, chloramphenicol and trimethoprim at breakpoint concentrations. RESULTS: The mean age of the volunteers was approximately 35 years; most of them were female. Ciprofloxacin resistance was in the range 1%-63%: the highest percentages were found in the urban populations of Asia and South America. In Peru and the Philippines (U and NU), the prevalence of gentamicin resistance was >20%. Cefazolin resistance was the highest in the urban Philippines (25%). Higher prevalences for ampicillin, oxytetracycline and trimethoprim were found for urban areas compared with non-urban ones of Asia, Africa and South America, respectively (P<0.05). CONCLUSIONS: In the populations studied, antibiotic resistance in faecal E. coli from adult volunteers was emerging for cefazolin, gentamicin and ciprofloxacin and was high for the older drugs ampicillin, oxytetracycline, trimethoprim and chloramphenicol.  相似文献   
238.
The Euregio Meuse-Rhine (EMR) is formed by the border regions of Belgium, Germany, and The Netherlands. Cross-border health care requires infection control measures, in particular since the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) differs among the three countries. To investigate the dissemination of MRSA in the EMR, 152 MRSA isolates were characterized by pulsed-field gel electrophoresis (PFGE), SCCmec typing, and multilocus sequence typing. PFGE revealed major clonal groups A, G, L, and Q, suggesting dissemination of MRSA in the EMR. Group A harbored mainly SCCmec type III and sequence types (STs) 239 and 241. The majority of the strains from group G harbored SCCmec type I and ST8 and ST247, whereas most strains from group L carried either SCCmec type IV or type I. Within group L, ST8 and ST228 were found, belonging to clonal complexes 8 and 5, respectively. Most strains from group Q included SCCmec type II and were sequence typed as ST225. Both ST225-MRSA-II and ST241-MRSA-III were novel findings in Germany. In addition, the SCCmec type of two isolates has not been described previously. One strain was classified as SCCmec type III but harbored the pls gene and the dcs region. Another strain was characterized as SCCmec type IV but lacked the dcs region. In addition, one isolate harbored both SCCmec type V and Panton-Valentine leukocidin. Finally, the SCCmec type of the strains was found to be correlated with the antibiotic susceptibility pattern.  相似文献   
239.
A retrospective study of donor blood availability and patterns of use from 1984 through 1988 was conducted in a 400-bed university teaching hospital in Nigeria by extraction of data from the master registers for blood donors and recipients. Blood transfusion requests, number of persons who underwent phlebotomy, number of crossmatches performed, and blood use increased each year during the period of study. Average wastage rate and crossmatch-to-transfusion ratio were 3.5 percent and 1.61, respectively. Replacement blood donation constituted 98 percent of available donor blood. Obstetrics and gynecology and surgery patients used 70.4 percent of the donor blood. The donor blood units were used as whole blood (81%) because of a lack of infrastructure such as a refrigerated centrifuge. Less than 5 percent of the donors were females. It is concluded that the levels of voluntary blood donation and general blood supply are unacceptably low. The need for a functional National Blood Transfusion Service is highlighted.  相似文献   
240.
Faecal samples from 180 patients on admission and 108 patients at discharge were analysed for the prevalence and degree of resistance of Escherichia coli and enterococci. Discharged patients had received 24 h cefazolin prophylaxis and had a mean hospital stay of 10 +/- 5 days. The prevalence of resistance of E. coli to amoxicillin (P < 0.05), cefazolin (P < 0.05) and oxytetracycline was higher for patients at discharge (41, 12 and 35%) than for patients at admission (28, 2 and 27%). The prevalence at discharge was higher after short-term (< or =7 days) than after long-term (>7 days) hospitalization, being significant for amoxicillin only (P < 0.05). No significant changes were observed for the enterococci.  相似文献   
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