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651.
Journal of Neurology - Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Metformin is reported to have pleiotropic neuroprotective effects through...  相似文献   
652.
Candida auris is a multidrug‐resistant yeast emerging in immunocompromised and in otherwise healthy individuals. Due to difficulties in microbiological identification of C. auris because of the lack of available laboratory technology in developing countries, the number of patients affected is most likely underestimated. We report the first case of C. auris otitis which now adds Iran as the fifth country around the Persian Gulf, in addition to Kuwait, Oman, United Arab Emirates and Saudi Arabia. Candida auris is an unknown pathogen in routine laboratories in Iran because most Candida isolates are probably misdiagnosed. Otomycosis seems to be a different clinical presentation of C. auris mainly involving isolates from the East‐Asian clade. We compared the mycological and clinical details of the Iranian patient with other cases of otitis reported since the last review of C. auris otomycosis in 2017.  相似文献   
653.

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs), as an alternative, are replacing corticosteroids in ocular inflammatory diseases. Diclofenac has been used mainly topically, and recent focus has been on intravitreal delivery. Both of these methods have been shown to have complications in long-term application.

Purpose

To assess the efficacy of slow release oral diclofenac sodium on intravitreal concentration in experimental model of chemically injured eyes.

Methods

In an experimental double-masked clinical trial, right eyes of 24 albino rabbits were chemically injured by 1 N NaOH. One hour after chemical injury, 10 cc suspension gavage containing 100 mg slow release diclofenac sodium was administered in all cases. 2, 4, 6, 12, 24, 48 h after gavage, vitreous samples were obtained in all cases. Intravitreal concentration of diclofenac sodium was evaluated in all samples using high-performance liquid chromatography (HPLC) method.

Results

Intravitreal diclofenac levels by oral intake were enhanced by the inflammation in all the measurements. In inflamed eyes, diclofenac concentration was ten times more than control eye (2.658 ± 0.344 vs. 0.242 ± 0.0279 and 1.617 ± 0.527 vs. 0.148 ± 0.095; in 2 and 4 h, respectively). After 6 h, diclofenac concentration was statistically different, although it reduced below 1 μg/ml.

Conclusion

Diclofenac is delivered to the inflamed eye more than healthy eye. It seems that by oral diclofenac consumption, it is possible to make a significant intravitreal concentration.
  相似文献   
654.

Objective

The aging effects on auditory change detection have been studied using the Mismatch Negativity (MMN) potential. However, recent studies have found earlier correlates of deviance detection at the level of the middle-latency response (MLR) and the effects of aging on this deviant-related response have not yet been clarified. The purpose of this study was to examine the effects of aging on both levels of the auditory deviance detection system.

Methods

MMN and MLR responses were recorded in 33 young and 29 older adults from 32 scalp electrodes during frequency oddball and swapped-oddball conditions.

Results

In the young group, modulation of MLR and a clear MMN response were observed, whereas in the aged group, no evidence of deviance detection was found at the level of MLR and the MMN amplitude was significantly diminished.

Conclusions

Based on the obtained results, aging affects both levels of the auditory deviance detection system which seems to be a result of deficits in regularity encoding along the auditory hierarchy.

Significance

The current findings suggest that age-related physiological changes result in deficits in regularity encoding, starting from early stages of processing. This might eventually affect stream segregation and induce difficulties in understanding speech in complex environments.  相似文献   
655.
Human epithelial mucin, MUC1, is commonly overexpressed in adenocarcinoma that includes more than 80% of breast cancers. The PR81 is a murine anti-MUC1 monoclonal antibody (MAb) that was prepared against the human breast cancer. We developed an indirect method for labeling of this antibody with (99m)Tc in order to use the new preparation in immunoscintigraphy studies of BALB/c mice bearing breast tumors. The (99m)Tc-PR81 complex was prepared using the HYNIC as a chelator and tricine as a coligand. The labeling efficiency determined by instant thin-layer chromatography (ITLC) was 89.2%+/-4.7%, and radiocolloides measured by cellulose nitrate electrophoresis were 3.4%+/-0.9%. The in vitro stability of labeled product was determined at room temperature by ITLC and in human serum by gel filtration chromatography - 88.3%+/-4.6% and 79.8%+/-5.7% over 24 h, respectively. The integrity of labeled MAb was checked by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis, and no significant fragmentation was seen. The results of cell binding studies showed that both labeled and unlabeled PR81 were able to compete for binding to MCF 7 cells. Biodistribution studies performed in female BALB/c mice with breast tumor xenografts at 4, 16 and 24 h after the (99m)Tc-HYNIC-PR81 injection demonstrated a specific localization of the compound at the site of tumors and minimum accumulation in non target organs. The tumor imaging was performed in BALB/c mice with breast xenograft tumors at 4, 8, 12, 16, 20, 24, 28, 32 and 36 h after the complex injection. The tumors were visualized with high sensitivity after 8 h. The findings showed that the new radiopharmaceutical is a promising candidate for radioimmunoscintigraphy of the human breast cancer.  相似文献   
656.
657.
OBJECTIVES: To study the early effect of axotomy on spinal motoneurons and dendritic trees in the newborn rat.METHODS: The left sciatic nerve of 50 neonatal Sprague--Dawley rats aged 5 days old was transected and the right area kept as a control. The operated animals were killed 2, 4, 8, 12 and 24 hours after axotomy. The L4--L6 segments of the spinal cord were sampled, and stained either with Golgi-Cox or Cresyl fast violet methods. The number of motoneurons, the largest soma diameter and the different parameters of the dendritic trees such as: number, length and thickness of the primary, secondary and tertiary branches in the axotomized sides were estimated and compared statistically with that of the intact sides.RESULTS: The results indicated that in the axotomized sides, the number of motoneurons and the largest soma diameter were decreased, but these were significant only in 12- and 24-hour groups. The number of branches of the dendritic trees including primary, secondary and tertiary branches was not significantly decreased in the groups. The thickness of the dendrites showed a reduction; however, this was significant only for the tertiary branches in the 24-hour groups. The length of the primary, secondary and tertiary branches of the dendrites--especially the latter--were also decreased significantly in most of the groups.CONCLUSION: Axotomy at the early stages in newborn rats resulted in noticeable morphometrical changes in motoneurons and their dendrites.  相似文献   
658.
A multivariate curve resolution method based on the combination of Kubista approach and iterative target transformation method of Gemperline has been proposed. This method is a soft model and need no information about the spectrum of the product and mechanism of the reaction. The method was used to study the degradation kinetics of nifedipin, 1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridine dicarboxilic acid dimethyl ester, upon exposure to the light of a 40 W tungsten lamp. The spectra of the nifedipine, collected at different lighting times, were subjected to the factor analysis and two chemical components were detected in the reaction system. Pure spectra of the components involved and their concentration profiles were obtained. The results revealed that the photodecomposition kinetics of nifedipine is zero-order at the beginning of the reaction. However, when the reaction preceded more than 50%, the kinetics of reaction changed to a first-order manner. The rate constants for the zero-order and first order regions were estimated as regions (4.96+/-0.13) x 10(-9) M(-1) s(-1) and (6.22+/-0.10) x 10(-5) s(-1), respectively.  相似文献   
659.
This research study investigated the effect of nicotine gum, clonidine, and naltrexone, in the maintenance treatment of cigarette smoking. In a double blind study, 171 nicotine-dependent male subjects who met DSM-IV criteria for nicotine dependence and smoking 10 cigarettes or more per day, were allocated randomly to three equal groups of 57. Subjects received nicotine gum, clonidine, or naltrexone over a 24-week treatment period. The nicotine gum dose was 2 mg every 1 to 2 h for the first 6 weeks, 2 mg every 2 to 4 h for the next 3 weeks, and 2 mg every 4 to 8 h for the remaining 15 weeks. The clonidine dose was 0.4 mg and the naltrexone dose was 50 mg per day. Continuous abstinence rates were recorded weekly for 24 weeks from the quit date. The abstinence rates by treatment groups were 36.8% for the nicotine gum group, 19.3% for the clonidine group, and 5.3% for the naltrexone group,and all between groups differences were significant. These results support the efficacy and safety of nicotine gum and clonidine for smoking relapse prevention among Iranian nicotine-dependent patients, but call in question the utility of naltrexone treatment for smoking relapse prevention.  相似文献   
660.
Chronic bronchitis is the most frequent late respiratory disease among Iranians exposed to mustard gas during the Iraq-Iran war. The aim of this study was to investigate efficacy of oral and intravenous corticosteroid therapy in improving lung function in mustard gas induced chronic bronchitis patients. 65 mustard gas-exposed chronic bronchitis patients, who were not responsive to standard treatments in exacerbation occasions, were randomly divided into two groups: an intravenous group (39 patients) receiving 500 mg intravenous methylprednisolone daily, and an oral group (26 patients) receiving 1 mg/kg oral prednisolone daily. Corticosteroid was tapered over the study period in both groups. Spirometery was performed on admission and on day 8 of therapy for assessment of effectiveness of therapy. There was significant improvement in spirometery indexes of both groups in approximately half of the patients over the study period. Furthermore, there was no difference between the pulse corticosteroid versus oral corticosteroid therapy in these patients. Since short-term corticosteroid therapy has a significant effect on lung function of almost fifty percent of patients with mustard gas-induced chronic bronchitis in exacerbation occasions, we suggest a short-term bolus steroid treatment to triage the patients into responders and non-responders for subsequent treatment.  相似文献   
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