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11.
Acute gastroenteritis (AGE) is a common illness in both adults and children worldwide and is caused by several microorganisms including viruses, bacteria, and parasites. Rotavirus (RV), which is the main cause of AGE, can occur as a mixed infection with other viruses. The aim of this study is to assess the molecular epidemiology of viral enteric viruses and assess RV coinfections with other enteric viruses and their influence on disease severity before and after RV vaccine introduction in children under 5 years of age. A total of 600 samples collected from children hospitalized for AGE in five large hospitals in Norway, and were analyzed for viral gastroenteritis agents by enzyme immunoassay and quantitative real-time polymerase chain reaction (qRT-PCR). Positive results confirmed either by Sanger sequencing or genotyped by multiplex semi-nested RT-PCR. In total, 243 of the 300 (81%) samples, collected from the prevaccine cohort, were positive for at least one of the four viruses tested in this study. RV was most frequently identified in 82.6% of the samples. In the postvaccine cohort, 114 of the 300 (38%) samples were positive for at least one of the viruses tested. RV found in 36.5% of the samples. Coinfections found less frequently in the postvaccine cohort. Among circulating enteric viruses in Norway, RV is the most important cause of viral gastrointestinal infection. As expected, there were fewer RV positive and fewer coinfections after RV vaccine implementation. The results provide valuable data that can aid in further evaluation of the vaccine impact.  相似文献   
12.

Background  

Estimates of baseline incidence of childhood intussusception could help safety monitoring after the introduction of rotavirus vaccines. We studied the incidence of intussusception in Uzbekistan, a GAVI-fund eligible state in Central Asia.  相似文献   
13.
To better assess the risk for transmission of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV), we obtained serial specimens and clinical and exposure data from seven confirmed U.S. SARS patients and their 10 household contacts. SARS-CoV was detected in a day-14 sputum specimen from one case-patient and in five stool specimens from two case-patients. In one case-patient, SARS-CoV persisted in stool for at least 26 days after symptom onset. The highest amounts of virus were in the day-14 sputum sample and a day-14 stool sample. Residual respiratory symptoms were still present in recovered SARS case-patients 2 months after illness onset. Possible transmission of SARS-CoV occurred in one household contact, but this person had also traveled to a SARS-affected area. The data suggest that SARS-CoV is not always transmitted efficiently. Routine collection and testing of stool and sputum specimens of probable SARS case-patients may help the early detection of SARS-CoV infection.  相似文献   
14.
Hypothyroidism in pregnancy is associated with serious maternal and fetal risk. Rarely, it is manifested by life-threatening cardiac complications, such as gross pericardial effusion and tamponade. We present a case of successfully treated gross pericardial effusion and tamponade in a 22-week pregnant woman with hypothyroidism. The patient was treated by pericardial drainage with further treatment of hypothyroidism with levothyroxine. During the follow-up pregnancy was uncomplicated without recurrence of pericardial effusion and successful delivery of full-term baby. We conclude that careful monitoring of thyroid functional tests and proper management should be performed in pregnant women with hypothyroidism to prevent cardiac complications of the disease, like pericardial effusion and tamponade.  相似文献   
15.
The resistance to picornaviral infection cells of susceptible lines has similar changes in the phenotype. They have decreased number of nucleoli and increased percentage of euploidy. Also the percentage of euploid cells those were resistant to the picornaviral infection increased in all highly transformed cultures. In resistant cells of all cultures has been found reduction of DNA. RNA amount also decreased both in nucleus and in cytoplasm. All these data correlated with the increased euploidy of the resistant population. The resistant cells had a less transformed phenotype, and decreased proliferative activity. Decreased nucleolar status became apparent by reduction of absolute and relative nucleolar indices. Consequently the reduction of viral titer (viral titters reduction) in resistant cells could be the direct result of diminished activity of the RNA synthesis machinery. It is important to note that the cells lose resistance while another type of virus, even from the same family, infects the culture once.  相似文献   
16.
17.
Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-μm-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm2. Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20.  相似文献   
18.
In-room air cleaners (ACs) and upper-room air ultraviolet germicidal irradiation (UVGI) are engineering control technologies that can help reduce the concentrations of airborne bacteria and fungal spores in the indoor environment. This study investigated six different types of ACs and quantified their ability to remove and/or inactivate airborne bacteria and fungal spores. Four of the air cleaners incorporated UV lamp(s) into their flow path. In addition, the efficacy of combining ACs with upper-room air UVGI was investigated. With the ventilation system providing zero or six air changes per hour, the air cleaners were tested separately or with the upper-room air UVGI system in operation in an 87-m3 test room. Active bacteria cells and fungal spores were aerosolized into the room such that their numbers and physiologic state were comparable both with and without air cleaning and upper-room air UVGI. In addition, the disinfection performance of a UV-C lamp internal to one of the ACs was evaluated by estimating the percentage of airborne bacteria cells and fungal spores captured on the air filter medium surface that were inactivated with UV exposure. Average airborne microbial clean air delivery rates (CADRm) varied between 26-981 m3 hr-1 depending on the AC, and between 1480-2370 m3 hr-1, when using air cleaners in combination with upper-room air UVGI. Culturing, direct microscopy, and optical particle counting revealed similar CADRm. The ACs performed similarly when challenged with three different microorganisms. Testing two of the ACs showed that no additional air cleaning was provided with the operation of an internal UV-C lamp; the internal UV-C lamps, however, inactivated 75% of fungal spores and 97% of bacteria cells captured in the air filter medium within 60 min.  相似文献   
19.
ObjectiveTo compare the gene dosage results achieved by a novel multiplex quantitative assay with cytogenetic and quantitative fluorescent polymerase chain reaction (QF-PCR) analysis for prenatal screening of trisomy 21 syndrome on corresponding fetal samples.Design and methodsFetal samples (n = 134) were collected from pregnant women considered high risk for having trisomy 21 affected fetus. Cytogenetic analysis and QF-PCR were performed. Then, the relative gene dosage of DSCAM and DYRK1A2 genes was determined on corresponding samples using comparative delta cycle of threshold (ΔCT) method.ResultsThe mean gene dosage ratio was 1.55 ± 0.11 (95% CI:1.51–1.58) in trisomy 21 cases and 1.01 ± 0.12 (95% CI:0.98–1.03) in normal samples (p value < 0.001). The results were in agreement to the results of cytogenetic and QF-PCR analysis with the overall specificity of 0.96 (95% CI:0.91–0.98) and the sensitivity of 0.80 (95% CI:0.49–0.94).ConclusionsThis gene dosage assay is appropriate for the screening of high risk pregnant women and is readily amenable to automation.  相似文献   
20.

Background

We aimed to estimate the societal costs of rotavirus cases among children less than 5 years in Kazakhstan, an upper-middle income country in Central Asia.

Methods

Data on medical, non-medical and indirect costs were collected for 190 patients less than 5 years, hospitalized with severe diarrhea in 2009 in two pediatric hospitals. Data on resource use for moderate and mild diarrhea cases were obtained from published sources. A probabilistic sensitivity analysis was performed to explore uncertainty in cost estimates.

Results

Approximately 4,000 severe, 30,700 moderate, and 122,900 mild rotavirus cases were estimated annually in children <5 years old. The mean societal cost of a severe, moderate and mild rotavirus case was estimated at US$ 454, 82, and 21, respectively. The total annual cost of rotavirus disease was $37.53 million or on average $107.36 for a child under 5 years old in Kazakhstan. Ninety-four percent of total costs (35.13 million) are indirect costs (productivity losses) from fatal cases and parents’ job absenteeism, while direct medical costs account for 2.04 million (5.4%), and direct non-medical for 0.46 million (1.2%).

Conclusions

Rotavirus-associated diarrhea represents a significant economic burden in Kazakhstan, largely due to indirect costs. The costs of rotavirus infections should be considered when planning further preventive actions, including the introduction of rotavirus vaccination.  相似文献   
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