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991.
Acute ischemia of the rectum is uncommon and usually occurs after aorto-iliac surgery. In this report, we present a case of
acute ischemic proctosigmoiditis that developed from a brief episode of hypotension. An 85-year-old male presented to the
emergency room with hypotension, mental confusion, and passage of maroon-colored stool. He was resuscitated and treated for
presumed sepsis. Computerized tomography of the abdomen and pelvis displayed signs of acute inflammation of the distal colon
and rectum. Endoscopic findings and microscopic examination of the rectal biopsy revealed changes consistent with acute ischemic
proctosigmoiditis. An evaluation for infectious etiologies was negative. The patient's clinical condition improved over the
next 24 h with supportive care. Involvement of the rectum is rare in ischemic colitis because of its abundant collateral blood
supply. Acute ischemic proctosigmoiditis should be considered in the differential diagnosis of elderly patients with multiple
co-morbidities presenting with hematochezia. 相似文献
992.
Mehdi Torabi Fereshteh Mazidi Sharaf Abadi Mohammad Reza Baneshi 《The American journal of emergency medicine》2018,36(5):816-819
Objectives
Hyperglycemia with unknown mechanism plays a predictive role in determining the prognosis of multiple trauma patients. The exact time of blood sugar measurement and the role of blood sugar changes in the monitoring of these patients have not been well established.Methods
This follow-up study was done on multiple trauma patients (> 18 years) with an Injury Severity Scores (ISS) > 16. These patients didn?t have any history of diabetes, underlying disease, or drug or alcohol use. Data collection was done by the questionnaire (checklist), and the patients were followed by the medical records. Cox regression was used to measure the effect of independent variables on the patients' hospital mortality.Results
Of a total of 963 patients, 280 patients were enrolled. Of those, 202 were male (72.1%) and 78 were female (27.9%). Hospital mortality was 18 (6.4%). Cox regression analysis suggested that those who had high blood sugar 3 h after admission had higher hospital mortality (P = 0.04). Changes in blood sugar, ΔBS (BS 3 h after admission – BS on admission), in these patients was also significantly correlated with hospital mortality (P < 0.001). The multivariate model using the backward conditional method showed that ΔBS (P < 0.001), international normalized ration (INR) (P < 0.001), and heart rate (P = 0.036) were significantly correlated with hospital mortality.Conclusions
In multiple trauma patients, blood sugar changes in the early hours of admission to the emergency department may help predict hospital mortality, but further studies are needed. Blood sugar monitoring in these patients during this time frame may be helpful in predicting these patients' outcomes. In addition, coagulopathy and tachycardia were significantly associated with hospital mortality. 相似文献993.
S. A. Salehizadeh Hossein Mahmoudi Chenari Mehdi Shabani Hossein Abbastabar Ahangar Reza Zamiri Avito Rebelo J. Suresh Kumar M. P. F. Graa J. M. F. Ferreira 《RSC advances》2018,8(4):2100
A BaCO3/BaSnO3/SnO2 nanocomposite has been prepared using a co-precipitation method without adding any additives. The prepared sample was characterized by using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. Detailed studies on the dielectric and electrical behavior (dielectric constant, complex impedance Z*, ac conductivity, and relaxation mechanisms) of the nanocomposite have been performed using the nondestructive complex impedance spectroscopy technique within the temperature range 150–400 K. The dielectric constant of the sample as a function of temperature showed the typical characteristics of a relaxor. The maximum dielectric constant value was observed to depend on frequency. The non-monotonic relaxation behavior of the prepared nanocomposite was evidenced from the spectra of loss tan, tan(δ). The relaxation kinetics was modeled using a non-Arrhenius model.A BaCO3/BaSnO3/SnO2 nanocomposite has been prepared using a co-precipitation method without adding any additives. 相似文献
994.
Masoud Karimlou Masoud Salehi Mehdi Imani Agha-Fatemeh Hosseini Afsaneh Dehnad Nasim Vahabi Mahmood Bakhtiyari 《International journal of occupational and environmental health》2015,21(4):279-284
Background
Work-related accidents result in human suffering and economic losses and are considered as a major health problem worldwide, especially in the economically developing world.Objectives
To introduce seasonal autoregressive moving average (ARIMA) models for time series analysis of work-related accident data for workers insured by the Iranian Social Security Organization (ISSO) between 2000 and 2011.Methods
In this retrospective study, all insured people experiencing at least one work-related accident during a 10-year period were included in the analyses. We used Box–Jenkins modeling to develop a time series model of the total number of accidents.Results
There was an average of 1476 accidents per month (1476·05±458·77, mean±SD). The final ARIMA (p,d,q) (P,D,Q)s model for fitting to data was: ARIMA(1,1,1)×(0,1,1)12 consisting of the first ordering of the autoregressive, moving average and seasonal moving average parameters with 20·942 mean absolute percentage error (MAPE).Conclusions
The final model showed that time series analysis of ARIMA models was useful for forecasting the number of work-related accidents in Iran. In addition, the forecasted number of work-related accidents for 2011 explained the stability of occurrence of these accidents in recent years, indicating a need for preventive occupational health and safety policies such as safety inspection. 相似文献995.
Mehdi MOHEBALI Behnaz AKHOUNDI Zahra KAKOOEI Zabih ZAREI Sorour CHAREHDAR Soheila MOLAEI 《Iranian Journal of Parasitology》2015,10(3):360-365
Background: Visceral leishmaniasis is systematic serous parasitic disease with public health importance. Zoonotic form of visceral leishmaniasis is wide spread in Mediterranean basin and South America regions. Direct agglutination test (DAT) is an accurate, reliable and non-expensive serological test for the diagnosis of visceral leishmaniasis in human and canines but the antigen preparation involves some limitations. This study aimed to compare the conventional production of DAT antigen with our modified DAT antigen and then assessed on human and dog pooled sera.
Methods: Conventional DAT antigen has been prepared at the School of Public Health, Tehran University of Medical Sciences and some modifications were carried out on it, which named as modified DAT antigen. Three positive and one negative human and dog pooled serum were separately used for the comparison of modified DAT with conventional DAT antigen batches with one-month interval for a period of 9 months.
Results: A good concordance was observed between modified DAT compared to conventional DAT antigens for the detection of visceral leishmaniasis on human (100%) and dog (94.4%) pooled sera, respectively.
Conclusion: Since the modified DAT antigen could be reduced the preparation time from 3 days to several hours and a good degree of agreement was found between modified DAT and convention DAT antigen batches, it can be used as a simple and easy tool for screening and serodiagnosis of human and canine L. infantum infection.Key Words: Direct agglutination test, Antigen modification, Visceral leishmaniasis 相似文献
996.
Mehdi NATEGHPOUR Gholamhossein EDRISSIAN Afsaneh MOTEVALLI HAGHI Leila FARIVAR Elham KAZEMI-RAD 《Iranian Journal of Parasitology》2015,10(4):547-553
Background:
The number of malaria cases is declining worldwide; however, it remains as a serious health problem. Diagnosing unusual cases is the most important issue to manage the problem. This study designed to describe the number of falciparum and vivax malaria infected patients referred to Malaria Reference Laboratory in Tehran University of Medical Science from 2000 to 2012.Methods:
A retrospective study was conducted based on the collected questionnaires from each patient referred to the laboratory. Diagnosing results and demographic information for positive cases were analyzed using SPSS software. Problematic cases were evaluated for any difficulties in diagnosis or in clinical signs. Scanning and molecular methods were performed whenever there was an atypical case referred to the laboratory. Some of the samples had various difficulties for diagnosing such as presence of fussed gametocytes and schizonts of Plasmodium falciparum in peripheral blood and CCHF like hemoragic disorders.Results:
Plasmodium vivax caused a large proportion of the cases (76.1%) in contrast with P. falciparum that included smaller proportion (22.8%) and the rest (1.1) belonged to mixed infection. Most of the positive cases (69.6%) were belonged to Afghani people. Men (94.6%) showed more infection than women (5.4%), moreover the most infection (44.5%) was seen at a range of 21–30 yr.Conclusion:
In the case of existing atypical issues to diagnose, it is needed to perform more precise microscopical examination beyond the current standard conditions. Sometimes molecular method is required to verify the exact agent of the disease. 相似文献997.
Hossein HAMIDINEJAT Massoud Reza SEIFI ABAD SHAPOURI Mohammad Mehdi NAMAVARI Parviz SHAYAN Marzieh KEFAYAT 《Iranian Journal of Parasitology》2015,10(1):69-77
Background:
Dense granules are immunodominant proteins for the standardization of immunodiagnostic procedures to detect neosporosis. In the presented study different fragment of a dense-granule protein was evaluated for serodiagnosis of Neospora caninum in cattle and water buffalo.Methods:
NcGRA7, from N. caninum tachyzoites was amplified. PCR product and pMAL-c2X plasmid were digested with EcoR1 restriction enzyme and expressed in Escherichia coli to evaluate its competence for detection of anti- N. caninum antibodies with ELISA in comparison with commercial IDEXX ELISA. Furthermore, 230 sera of presumably healthy cattle and water buffaloes (108 cattle and 122 water buffaloes) were analyzed by both tests to determine the agreement of these two procedures.Results:
Sensitivities and specificities of NcGRA7-based ELISA were 94.64% and 90.38% respectively using sera of cattle, but were 98.57% and 86.54% in the case of buffaloes respectively. A good correlation between the results of IDEXX ELISA and ELISA based on recombinant NcGRA7 for detecting N. caninum antibodies was appeared. Analyzing by Mc Nemar′s showed that NcGRA7-based ELISA has acceptable capability to differentiate the positive results in comparison with IDEXX ELISA.Conclusion:
NcGRA7-based ELISA considering utilized new fragment of genomic DNA is a good tool for serodiagnosis of anti- N. caninum antibodies for screening and epidemiological purposes on cattle herd and water buffaloes as well. 相似文献998.
Inder M. Singh MD MS Steven J. Filby MD Fredy El Sakr BS Eiran Z. Gorodeski MD MPH A. Michael Lincoff MD FACC Stephen G. Ellis MD FACC Mehdi H. Shishehbor DO MPH 《Catheterization and cardiovascular interventions》2010,76(2):257-262
Objectives : We compared the long‐term outcomes of drug‐eluting stents (DES) versus bare‐metal stents (BMS) for treatment of bare‐metal in‐stent restenosis (ISR). Background : There are no randomized trials or observational studies directly comparing the safety and efficacy of DES versus BMS for treatment of bare‐metal ISR. Methods : We examined data on all patients who underwent percutaneous coronary intervention (PCI) for ISR at Cleveland Clinic between 05/1999 and 06/2007. We compared the efficacy and safety of DES to BMS for treating bare‐metal ISR. The primary end point was a composite of death, myocardial infarction (MI), or target lesion revascularization (TLR). The secondary endpoints were individual components of the primary endpoint. Results : Of the 931 patients identified over 8 years, 706 had bare‐metal ISR and met our study criteria. Of the 706 patients with bare‐metal ISR, 362 were treated with DES and 344 with BMS. There were 230 cumulative events for a median follow‐up of 3.2 years. After adjusting for 27 variables, DES were associated with lower primary endpoint compared to BMS for treatment of bare‐metal ISR (21% vs. 45%, adjusted hazard ratio [HR] 0.63; 95% confidence interval [CI], 0.42–0.95; P = 0.03). The individual secondary endpoint of death (8% vs. 24%, P = 0.005) favored DES, but MI (3% vs. 8%, P = 0.31), and TLR (13% vs. 20%, P = 0.23) failed to reach statistical significance. Conclusions : In our multivariate analysis of patients with bare‐metal ISR, DES use was associated with significantly lower death, MI, or TLR when compared to BMS. © 2010 Wiley‐Liss, Inc. 相似文献
999.
Davis JC Marra CA Beattie BL Robertson MC Najafzadeh M Graf P Nagamatsu LS Liu-Ambrose T 《Archives of internal medicine》2010,170(22):2036-2038
1000.
Zamani S Vazirian M Nassirimanesh B Razzaghi EM Ono-Kihara M Mortazavi Ravari S Gouya MM Kihara M 《AIDS and behavior》2010,14(4):885-890
This study was conducted to compare needle and syringe sharing practices among injecting drug users (IDUs) in two neighborhoods,
one with and one without a needle and syringe program (NSP). In 2005, 419 street-based IDUs were interviewed at specific locations
in two neighborhoods where IDUs are known to congregate. We compared self-reported needle and syringe access and use between
IDUs from a neighborhood with an active NSP to IDUs from a neighborhood without such an intervention. A significantly smaller
proportion of IDUs from the former neighborhood reported having used a shared needle/syringe over a 1-month period (21.0%)
compared to IDUs from the latter neighborhood (39.9%; adjusted odds ratio, 0.24; 95% confidence interval, 0.13–0.45). These
findings indicate that access to an NSP may reduce needle and syringe sharing practices. Therefore, these programs should
be intensified in settings with concentrated HIV epidemics among IDUs in Iran. 相似文献