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11.
Acanthamoeba castellanii is a protozoan parasite that may cause sight-threatening keratitis in some individuals. Its eradication is difficult because the trophozoites encyst making organisms highly resistant to anti-amoebic drugs. To test new anti-Acanthamoeba agents, usually having low water solubility, organic solvents and surfactant agents should be used. Therefore, the lethal effect of different concentrations of the solvents acetone, methanol, ethanol, and DMSO and surfactant agents Tween 20, Tween 80, and Triton X-100 was tested. The minimal inhibitory concentrations (MIC) were determined against Acanthamoeba cysts. Results of the present study showed that the MIC for ethanol, methanol, acetone and DMSO was 25, 12.5, 12.5, and 10 %, respectively and for Tween 20, Tween 80, and Triton X-100 was 0.25, 0.06, and 0.03 %, respectively. There was no significant inhibitory effect on the multiplication of Acanthamoeba cysts as compared to parasite control when using the concentrations 3.12 % for ethanol, 1.6 % for methanol and acetone, 1.25 % for DMSO, and 0.016 % for Tween 20. On the other hand, both Tween 80 and Triton X-100 showed highly significant difference in comparison to parasite control almost among all the range of concentrations used in this study, and both showed lethal effect of 19 and 27.2 %, respectively at their least concentration.  相似文献   
12.
Abstract

Objectives: Headache is one of the most common complaints in medicine. Epidemiological and population-based studies reported that migraine has a variable prevalence worldwide. This study was done to estimate the prevalence of migraine across various age groups in Assiut district, Egypt.

Methods: This is a door-to-door study. It included 4700 randomly selected individuals.

Results: Headache was reported in 1668 subjects (35.49%), of them, 87.65% (n = 1462) had primary headaches. Migraine prevalence was 10.51% with female-to-male ratio of 2.4:1 particularly in ages of 20–40 years. The mean age of patients was 31.46 ± 13.39 years and age at onset was 24.16 ± 12.10 years. Nearly, 63.5% had frequent attacks, 65.2% of the attacks were severe enough to stop daily activities and lasted for >1 day in 32.5% of females compared to 40.7% and 14.5% for males. Chronic or daily migraine was more in females (35.3% versus 20.7% for males). Approximately, 5.6% had chronic migraine and 1.2% had daily migraine from the start, while 24.2% had transformation from episodic to chronic migraine within 6.1 ± 4.4 years. Migraine was prevalent among those with middle educational levels and labor workers. The duration of migraine attacks was found to reduce with age but the chronic/daily migraine increased with age. Hypertension, anxiety, irritable bowel syndrome, and depression were common comorbidities with migraine.

Conclusions: We believe that the work done in this study is informative as it determined the actual prevalence of migraine across various age groups and the important predictors of change in the severity, duration, and frequency of migraine in our locality.  相似文献   
13.
SARS-CoV-2 nasopharyngeal shedding contributes to the spread of the COVID-19 epidemic. Among 3271 COVID-19 patients treated at the Hospital University Institute Méditerranée Infection, Marseille, France from 3 March to 27 April 2020, tested at least twice by qRT-PCR, the median SARS-CoV-2 nasopharyngeal shedding duration was 6 days (range 2–54 days). Compared with short shedders (qRT-PCR positivity < 10 days), 34 (1.04%) persistent shedders (qRT-PCR positivity ≥ 17 days; mean ± SD: 23.3 ± 3.8 days) were significantly older, with associated comorbidities, exhibiting lymphopenia, eosinopenia, increased D-dimer and increased troponin (p < 0.05), and were hospitalized in intensive care unit in 17.7% vs. 1.1% of cases (p < 0.0001). Viral culture was positive in six persistent shedders after day 10, including in one patient after day 17, and no viral co-pathogen was detected in 33 tested patients. Persistent shedders received azithromycin plus hydroxychloroquine ≥ 3 days in 26/34 (76.5%) patients, a figure significantly lower than in short shedders (86.6%) (p = 0.042). Accordingly, mortality was 14.7% vs. 0.5% (p < 0.0001). Persistent shedding was significantly associated with persistent dyspnea and anosmia/ageusia (p < 0.05). In the context of COVID-19 treatment, including treatment with azithromycin plus hydroxychloroquine, the persistence of SARS-CoV-2 nasopharyngeal shedding was a rare event, most frequently encountered in elderly patients with comorbidities and lacking azithromycin plus hydroxychloroquine treatment.  相似文献   
14.
Angiogenesis has a significant pathogenic role in liver damage-associated hepatitis C virus infection. We evaluated whether chronic hepatitis C (CHC) is associated with elevated levels of angiogenesis marker (vascular endothelial growth factor) and whether it is modulated by therapy. Vascular endothelial growth factor (VEGF) mRNA was determined in the 36 CHC patients included in this study before therapy and 12 weeks after receiving antiviral combination therapy, pegylated interferon alpha-2b plus ribavirin, compared to 20 healthy controls. CHC patients showed elevated baseline VEGF level before and during treatment, but it was decreased in responder group, indicating a shift toward an “anti-angiogenic” process in CHC patients. In conclusion, this suggests that VEGF mRNA level could be useful as non-invasive, base markers of response to therapy.  相似文献   
15.
Photorefractive keratectomy (PRK) is considered a safe approach laser procedure with a clinical significance in correcting myopia results. PRK requires removing the whole superficial epithelium. The integrity of the epithelial basement membrane and the deposition of abnormal extracellular matrix can put the cornea in a probable situation for corneal haze formation. Mitomycin C (MMC) is applied after excimer laser ablation as a primary modulator for wound healing, limiting corneal haze formation. We aim to summarize the outcomes of MMC application after laser ablation. We searched Scopus, PubMed, Cochrane CENTRAL, and Web of Science till December 2020 using relevant keywords. The data were extracted and pooled as mean difference (MD) or risk ratio (RR) with a 95% confidence interval (CI), using Review Manager software (version 5.4). Our analysis demonstrated a statistically significant result for MMC application over the control group in terms of corneal haze formation postoperatively (RR = 0.29, 95% CI: [0.19, 0.45], P < 0.00001). Regarding corrected distance visual acuity (CDVA), no significant difference was observed between the MMC group and the control group (MD = 0.02; 95% CI: [-0.04, 0.07]; P = 0.56). Regarding the uncorrected distance visual acuity (UDVA), the analysis favored the MMC application with (MD -0.03, 95% CI: [-0.06, -0.00]; P = 0.05). There was no statistically significant increase in complications with MMC. In conclusion, MMC application after PRK is associated with a lower incidence of corneal haze formation with no statistically significant side effects. The long term effect can show improvement regarding UDVA favoring MMC. However, there is no significant effect of MMCs application regarding CDVA, and SE.  相似文献   
16.
A 3‐year‐old child presented with recurrent chest pain for 3 months, echocardiography showed a thorn inside the left ventricle, the patient was diagnosed with foreign body complicated with infective endocarditis and received proper treatment, and operation was performed after inflammatory reaction subsided.  相似文献   
17.
18.
The persistence of antigen-specific memory B-cells (MBCs) in children and young adults long time after vaccination against measles, mumps and rubella (MMR) is not known. Here we have looked at the Swedish immunization program and examined children 1–10 years after the first MMR dose in early childhood, as well as young adults 7–18 years after the second dose of MMR. We show that Ab titers and MBCs against measles and rubella have different kinetics, indicating that the MBC pool and the corresponding Ab titers are regulated independently. These data fit well with other findings that continuous IgG secretion comes from long-lived plasma cells and not MBCs. We also demonstrate that individuals with low post-vaccination Ab titers might have an adequate MBC response. It remains to be shown if memory B-cells provide the same protection as specific antibodies, but our data is a valuable complement to the incomplete knowledge about correlates of protection after vaccination.  相似文献   
19.
In the face of spreading chloroquine and sulfadoxine-pyrimethamine (SP) resistance, amodiaquine remains a cheap and efficacious alternative for treating uncomplicated Plasmodium falciparum malaria in many settings. In Harper, south-eastern Liberia, a previous study we conducted showed very high levels of resistance to both chloroquine and SP. In 2001, in an effort to look for possible alternatives, we measured in the same setting the efficacy of amodiaquine in a 28-d study in vivo, with results corrected by polymerase chain reaction genotyping to distinguish recrudescences from reinfections. In total, 107 children were included in the study and received a 3-d supervised course of 25 mg/kg amodiaquine. Of these, 81 were analysable at day 28. The overall failure rate was 19.8% (95% CI 11.7-30.1%) considering both parasitological and clinical outcomes. These results provide hitherto missing data on amodiaquine in Liberia, and confirm that the drug may still be efficacious in settings where chloroquine and SP are failing. We recommend the introduction of amodiaquine in association with artesunate as a first-line antimalarial in Harper.  相似文献   
20.
A drug-resistance survey was conducted in the French territory of Mayotte in the Comorian Islands in the Indian Ocean where malaria is endemic. A high prevalence of resistant Plasmodium falciparum parasites was observed, not only to chloroquine (88%) and pyrimethamine (99%), but more surprisingly to quinine (17%), mefloquine (9%), and amodiaquine (24%). This leaves few treatment alternatives other than artemisine-mefloquine combinations. However, despite notification to French Health authorities three years ago, inadequate treatment (chloroquine plus sulfadoxine-pyrimethamine) is still used in this locality. Thus, people still die of malaria in this remote territory of France.  相似文献   
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