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BackgroundIn February 2020, the Ministry of Health and Medical Education in Iran announced the first case of COVID-19. The aim of this study was to investigate the impact of COVID-19 on the number of CT-Scans and MRI services in public hospitals in western Iran.MethodsWe collected CT-scans and MRI services data from 18 public hospitals via Vice-Chancellor Office, Lorestan University of Medical Sciences from January 2017 to February 2021. Interrupted time series analysis (ITSA) was conducted to assess the impact of COVID-19 on CT-Scans and MRI services. More specifically, ITSA was conducted using ordinary least squares regression with the number of CT-Scans and MRI services per 1,000 registered persons per month as dependent variable.ResultsAt the beginning of the observation period, the monthly rate of CT-Scans was constant (p for trend = 0.267) at 291.9 (from 95%CI 240.5 to 343.4) per 1,000 registered patients. The first case of COVID-19 coincided with an abrupt increase by 211.8 (from 95%CI 102.9 to 320.7) per 1,000 patients. Thereafter, the trend of CT-Scans did not change (p=0.576) compared to the pre-pandemic period. The rate of MRI services was 363.5 per 1,000 per registered patients per month (P = <0.0001) with a slightly decreasing trend (coefficient=-5; 95%CI, -6.9 to -3.1).ConclusionThe findings of this study showed that crises such as COVID-19 can affect the service delivery process. Health policymakers and decision makers should work to prevent potential reductions in health care during events such as COVID-19.  相似文献   
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After the initial study of different protocols in the synthesis of indeno[2′,1′:5,6]pyrido[2,3-d]pyrimidines, herein, a new method is presented using cheaper and more accessible starting materials to produce high-efficiency products. In this protocol, the novel nanocatalyst is very effective in the progression of the reaction and increasing the efficiency. This green approach in aqueous media has several advantages as compared with other methods, such as easier work-up, very mild reaction conditions, reusability of the catalyst, and eco-friendliness. The products of this four-component condensation were evaluated using IR, 1H NMR, 13C NMR spectra, and C. H. N. analyses, and the catalyst structure was confirmed by FT-IR, XRD, SEM, EDX, TGA and VSM techniques.

In this protocol, a novel nanocatalyst was very effective in progression of the reaction and increasing efficiency. This green approach in aqueous media has several advantages compared with the reported methods.  相似文献   
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Background and goals  This study is designed to survey gestational trophoblastic neoplasia with vaginal metastases (GTN + VM) manifestations, prognosis and chemotherapy response in order to consider appropriate chemotherapy regimen for these patients. There have been just a few studies about treatment of GTN + VM. Materials and methods  Patients with Stage III GTN with or without vaginal metastases who had referred to Vali-e-Asr Hospital during 1996–2006 have been selected to take part in this study and the size of metastases was measured. Then response and resistance to single and combination chemotherapy regimens have been compared in these two groups. The data were processed using SPSS system (release 10). Statistical analysis was done with X2 to determine factors associated with complete clinical response. The level of significance was assigned at P < .05. Results  Forty-eight patients with stage III (with pulmonary metastases) GTN patients have been selected, 13 with vaginal metastases and 35 without vaginal metastases. Incidence of vaginal metastases in stage III was 26%. Metastases were mainly in distal part of vagina and suburethra. Chief complaint was severe hemorrhage in 25% of patients and was controlled by vaginal packing with just one exception. Group of vaginal metastases showed 66.6% resistance to first-line chemotherapy, compared to 28.6% in patients with no vaginal metastases (P-value = 0.010). Median of chemotherapy courses in low-risk vaginal metastatic patients was 5 (mean = 5.2), compared to three courses in the group without vaginal metastases. Resistance to single chemotherapy was significantly higher in GTN + VM versus GTN without VM patients and resistance was higher especially in patients with metastases with more than 3 cm (in diameter). Conclusions  Vaginal metastasis with more than 3 cm in diameter is an important prognostic factor in GTN patients. There have higher risks for severe hemorrhage and resistance to single agent chemotherapy, so in these patients combination chemotherapy, with no regard to staging and scoring, would be a better choice. An erratum to this article can be found at  相似文献   
16.

Ethnopharmacological relevance

The experimental finding of Asian traditional medicine revealed the pharmacological effect of the local application of ghee which was taken from cow butterfat and the rhizomes of Curcuma longa. These materials significantly improved the healing process of the wound. In addition, ancient physicians of Middle East discovered that the powdered rhizomes of Curcuma longa (common turmeric) also had impressive medicinal qualities. Over the centuries, this spice has been used as a pain relieving, anti-inflammatory agent to relieve pain and inflammation in the skin and muscles.

Aim of the study

We decided to mix ghee which was taken from sheep butterfat with the powdered rhizomes of Curcuma longa to formulate a novel cost-benefit material and then, evaluate its potential therapeutic effect on acceleration of surgical wound healing; moreover, this present study was performed to compare the effects of Curcuma longa–ghee formulation and hyaluronic acid on gingival wound healing following surgery.

Materials and methods

Five healthy 3-year-old male beagle dogs were used in this study. They had intact teeth and the clinical and radiographic examination revealed no periodontal disease. Ghee was obtained from the refined sheep butterfat heated to 70 °C mixed with the powdered rhizomes of Curcuma longa and was applied with two different ratios including materials A and B. Randomly, these three materials including hyaluronic acid, materials A and B were applied topically in test regions and then covered with periodontal pack. Histological changes were monitored in days 4 and 7 after operation to evaluate the inflammatory and repair stage of healing process.

Results

We observed significant difference in the inflammatory and repair parameters of the healing process between cases treated with this new formulation and cases of hyaluronic acid application.

Conclusion

The results suggested a positive potential therapeutic effect on surgical wound healing particularly improvement of periodontal treatment consequences after surgery.  相似文献   
17.
Oxidative damage is the earliest event in Alzheimer disease   总被引:32,自引:0,他引:32  
Recently, we demonstrated a significant increase of an oxidized nucleoside derived from RNA, 8-hydroxyguanosine (8OHG), and an oxidized amino acid, nitrotyrosine in vulnerable neurons of patients with Alzheimer disease (AD). To determine whether oxidative damage is an early- or end-stage event in the process of neurodegeneration in AD, we investigated the relationship between neuronal 8OHG and nitrotyrosine and histological and clinical variables, i.e. amyloid-beta (A beta) plaques and neurofibrillary tangles (NFT), as well as duration of dementia and apolipoprotein E (ApoE) genotype. Our findings show that oxidative damage is quantitatively greatest early in the disease and reduces with disease progression. Surprisingly, we found that increases in A beta deposition are associated with decreased oxidative damage. These relationships are more significant in ApoE epsilon4 carriers. Moreover, neurons with NFT show a 40%-56% decrease in relative 8OHG levels compared with neurons free of NFT. Our observations indicate that increased oxidative damage is an early event in AD that decreases with disease progression and lesion formation. These findings suggest that AD is associated with compensatory changes that reduce damage from reactive oxygen.  相似文献   
18.
A 7-year-old boy with hypertension secondary to intimal hyperplasia of the left renal artery was normotensive after laparoscopic autotransplantation following failed angioplasty. This appears to be the first such case reported.  相似文献   
19.
OBJECTIVES: To determine the incidence of chromosome abnormalities among couples for whom intracytoplasmic sperm injection (ICSI) treatment was indicated and fetuses conceived through the ICSI procedure. METHODS: All cytogenetic results were evaluated retrospectively. Patients undergoing ICSI (n = 508) were classified according to the referring indications as: (1) males with severe infertility (87 azoospermia and 34 oligoasthenoteratozoospermia, OAT), (2) prior to ICSI (56 males and 61 females), and (3) following an unsuccessful ICSI procedure (132 males and 138 females). Fetuses conceived through ICSI (n = 475) were also classified into 4 groups according to the additional risk factors for chromosome abnormalities: ICSI (n = 185), ICSI + advanced maternal age (AMA, n = 215), ICSI + positive triple test result (TT, n = 50), and ICSI + abnormal ultrasound findings (USG, n = 25). RESULTS: An abnormal karyotype was found in 31.03% of males with azoospermia and 14.71% of males with OAT, in 3.57% of males and 1.64% of females in the group prior to ICSI, and in 5.30 and 5.07%, respectively, in the group following unsuccessful ICSI treatment. Gonosomal aneuploidies were predominant in males with azoospermia and autosomal rearrangements in males with OAT, while low-level sex chromosome mosaicism was found in females. The overall frequency of chromosome abnormalities in fetuses was 4.42% and varied in the different groups from 1.62% in ICSI, 2.79% in ICSI + AMA, 10.0% in ICSI + TT to 28.0% in ICSI + USG. The frequencies of the different types of chromosome abnormalities were as follows: balanced 1.05%, unbalanced 3.37%, familial 0.84%, de novo 3.37%, autosomal 3.58%, gonosomal 0.84%, numerical 1.89%, structural abnormalities 2.53%, and mosaicism 1.26%. CONCLUSION: Our results indicate that cytogenetic investigations of the ICSI parents and fetuses are essential for the families, genetic counselors and also reproductive centers. In fetal karyotyping, de novo structural chromosome abnormalities and mosaicism should be taken into consideration.  相似文献   
20.
Selective neuronal dysfunction and degeneration are defining features of Alzheimers disease (AD). While the exact mechanism(s) contributing to this selective neuronal vulnerability remains to be elucidated, we hypothesized that the differential expression of metabotropic glutamate receptors (mGluRs) may play a key role in this process since the various mGluR groups differentially regulate neuronal cell death and survival. In the present study, we focused on the metabotropic glutamate receptor 2 (mGluR2), a subtype of group II mGluRs. The mGluR2 is expressed at low levels in pyramidal neurons in age-matched control cases, whereas we found a strikingly increased mGluR2 expression in AD, in a pattern that mirrored both the regional and cellular subtype of neuronal vulnerability to degeneration and neurofibrillary alterations. Immunoblot analysis confirmed the significant increase in the level of mGluR2 in AD compared with age-matched controls. Agonists for group II mGluRs activate extracellular receptor kinase (ERK), a kinase that is chronically activated in vulnerable neurons of AD. ERK is able to phosphorylate tau protein, so the up-regulation of mGluR2 in vulnerable neurons may represent the upstream mediator of abnormal tau phosphorylation in AD. Immunocytochemical examination revealed considerable overlap between mGluR2 and neurofibrillary alterations. Thus, it is likely that mGluR2 represents a novel therapeutic target for AD.  相似文献   
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