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81.
Pastoral nomadism, as a successful economic and social system drawing on mobile herding, long-distance trade, and cavalry warfare, affected all polities of the Eurasian continent. The role that arid Inner Asia, particularly the areas of northwestern China, Kazakhstan, and Mongolia, played in the emergence of this phenomenon remains a fundamental and still challenging question in prehistoric archaeology of the Eurasian steppes. The cemetery of Liushiu (Xinjiang, China) reveals burial features, bronze bridle bits, weaponry, adornment, horse skulls, and sheep/goat bones, which, together with paleopathological changes in human skeletons, indicate the presence of mobile pastoralists and their flocks at summer pastures in the Kunlun Mountains, ~2,850 m above sea level. Radiocarbon dates place the onset of the burial activity between 1108 and 893 B.C. (95% probability range) or most likely between 1017 and 926 B.C. (68%). These data from the Kunlun Mountains show a wider frontier within the diversity of mobile pastoral economies of Inner Asia and support the concept of multiregional transitions toward Iron Age complex pastoralism and mounted warfare.  相似文献   
82.
Dysregulation of cerebral vascular function and, ultimately, cerebral blood flow (CBF) may contribute to complications such as stroke and cognitive decline in diabetes. We hypothesized that 1) diabetes-mediated neurovascular and myogenic dysfunction impairs CBF and 2) under hypoxic conditions, cerebral vessels from diabetic rats lose myogenic properties because of peroxynitrite (ONOO(-))-mediated nitration of vascular smooth muscle (VSM) actin. Functional hyperemia, the ability of blood vessels to dilate upon neuronal stimulation, and myogenic tone of isolated middle cerebral arteries (MCAs) were assessed as indices of neurovascular and myogenic function, respectively, in 10- to 12-week control and type 2 diabetic Goto-Kakizaki rats. In addition, myogenic behavior of MCAs, nitrotyrosine (NY) levels, and VSM actin content were measured under normoxic and hypoxic [oxygen glucose deprivation (OGD)] conditions with and without the ONOO(-) decomposition catalyst 5,10,15,20-tetrakis(4-sulfonatophenyl) prophyrinato iron (III), chloride (FeTPPs). The percentage of myogenic tone was higher in diabetes, and forced dilation occurred at higher pressures. Functional hyperemia was impaired. Consistent with these findings, baseline CBF was lower in diabetes. OGD reduced the percentage of myogenic tone in both groups, and FeTPPs restored it only in diabetes. OGD increased VSM NY in both groups, and although FeTPPs restored basal levels, it did not correct the reduced filamentous/globular (F/G) actin ratio. Acute alterations in VSM ONOO(-) levels may contribute to hypoxic myogenic dysfunction, but this cannot be solely explained by the decreased F/G actin ratio due to actin nitration, and mechanisms may differ between control and diabetic animals. Our findings also demonstrate that diabetes alters the ability of cerebral vessels to regulate CBF under basal and hypoxic conditions.  相似文献   
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Background and study aimsBoth hepatitis C virus (HCV) and schistosomiasis are highly endemic in Egypt and coinfection is frequently encountered. Such coinfection is responsible for leading to a more severe liver disease. Hence, the aim of the study was to assess the fibroscan in chronic HCV patients coinfected with Schistosoma.Patients and methodsThis study included 231 chronic HCV patients. Routine pre-treatment work-up was done including anti-schistosomal antibodies. Liver stiffness measurements using fibroscan and reference needle-liver biopsy were done. Patients were categorised into two groups: HCV patients with positive schistosomal serology and HCV patients with negative schistosomal serology.ResultsAnti-schistosomal antibody was positive in 29% of the studied population. Positive schistosomal serology status was significantly associated with the disagreement between the results of liver biopsy (Metavir) and the fibroscan results (p value = 0.02), which was more obvious in F2 and F3 fibrosis stages. The sensitivity of fibroscan for the detection of the F2 stage decreased from 64% among negative schistosomal serology patients to 30.8% among positive schistosomal serology patients, and for the F3 stage it decreased from 43.8% to 21.4%, respectively. Multivariate logistic regression showed that fibrosis stages (F0–F1 and F4) were the most independent factors that were associated with the agreement between fibroscan and liver biopsy (odds ratio (OR) 3.4, 7.12 and p value <0.001, <0.001, respectively).ConclusionAlthough the sensitivity of fibroscan for the detection of fibrosis stages (F2 and F3) was impaired in patients with positive schistosomal serology, fibrosis stages (F0–F1 and F4) were the most independent factors associated with the agreement between fibroscan and liver biopsy.  相似文献   
86.
Objectives  To describe the biomedical and other causes of maternal death in Syria and to assess their preventability.
Methods  A reproductive age mortality study (RAMOS) design was used to identify pregnancy related deaths. All deaths among women aged 15–49 reported to the national civil register for 2003 were investigated through home interviews. Verbal autopsies were used to ascertain the cause of death among pregnancy related maternal deaths, and causes and preventability of deaths were assessed by a panel of doctors.
Results  A total of 129 maternal deaths were identified and reviewed. Direct medical causes accounted for 88%, and haemorrhage was the main cause of death (65%). Sixty nine deaths (54%) occurred during labour or delivery. Poor clinical skills and lack of clinical competency were behind 54% of maternal deaths. Ninety one percent of maternal deaths were preventable.
Conclusions  The causes of maternal death in Syria and their contributing factors reflect serious defects in the quality of maternal care that need to be urgently rectified.  相似文献   
87.
In order to guide the antimalarial treatment policy of Somalia, we conducted therapeutic efficacy studies of routinely used antimalarial monotherapies as well as artemisinin-based combination therapies (ACTs) for uncomplicated malaria in three sentinel sites during 2003-2006. Therapeutic efficacy of chloroquine (CQ), amodiaquine (AQ) and sulfadoxine/pyrimetahmine (SP) monotherapies, and artesunate plus SP (AS + SP) or AQ (AS + AQ) were evaluated in children 6 months to 10 years old with uncomplicated malaria. For the assessment of the monotherapies, 2003 WHO protocol with 14-day follow-up was used while the 2005 WHO protocol with 28-day follow-up was used for testing the ACTs. Of the monotherapies, CQ performed very poorly with treatment failures varying from 76.5% to 88% between the sites. AQ treatment failure was low except for Janale site with treatment failure of 23.4% compared to 2.8% and 8% in Jamame and Jowhar, respectively. For SP, treatment failures from 7.8% to 12.2% were observed. A 28-day test of artemisinin-based combinations, AS + SP and AS + AQ, proved to be highly efficacious with cure rates of 98-100% supporting the choice of AS + SP combination as first line treatment for uncomplicated malaria for Somalia.  相似文献   
88.
Improved laboratory diagnosis is critical to reduce the burden of malaria in pregnancy. Peripheral blood smears appear less sensitive than Plasmodium falciparum histidine-rich protein 2-based rapid diagnostic tests (RDTs) for placental malaria infections in studies conducted at delivery. In this study, 81 women in Uganda in the second or third trimester of pregnancy were followed-up until delivery. At each visit, peripheral blood was tested by blood smear, RDT, and nested species-specific polymerase chain reaction (PCR). Sensitivity and specificity of the tests was calculated with PCR, which detected 22 infections of P. falciparum, as the gold standard. The sensitivity and specificity of blood smears were 36.4% (95% confidence interval [CI] = 18.0-59.2%) and 99.6% (95% CI = 97.7-100%), respectively. The corresponding values for RDT were 31.8% (95% CI = 14.7-54.9%) and 100% (95% CI = 98.3-100%). The RDTs could replace blood smears for diagnosis of malaria in pregnancy by virtue of their relative ease of use. Field-based sensitive tests for malaria in pregnancy are urgently needed.  相似文献   
89.
Background: Huge efforts have been made to control chronic HCV in Egypt with introduction of Direct-Acting Antivirals (DAAs). Current study aims at evaluating effect of various DAA regimens on liver biochemical profile and haematological indices during treatment.

Methods: 272 patients with chronic HCV genotype 4 treated by different DAA regimens (SOF/RBV, SOF/DAC ± RBV, SOF/SIM) for a duration of 12 or 24 weeks in Kasr Alainy Viral Hepatitis Center, Cairo University were followed up for serum bilirubin (BIL), albumin (ALB), alanine transaminase (ALT), aspartate aminotransferase (AST), prothrombin concentration, international normalized ratio (INR), and CBC at baseline, week-4 and end of treatment.

Results: Mean age was 54 years. Males comprised 64.7%, 72.4% were treatment-naïve, 39% were cirrhotic. Overall SVR12 rate was (93.4%). With all regimens, ALT and AST declined after treatment. In cirrhotics, there was a rise in BIL and INR; with no change in ALB and a decrease in White blood cells. Drop in Hemoglobin and platelets in cirrhotic patients were noted with SOF/RBV, while SOF/SIM showed rise in BIL.

Conclusion: DAAs are safe and effective in genotype 4 chronic HCV patients. It improves liver necro-inflammatory markers in cirrhotics and non-cirrhotics. Cirrhotic patients require careful observation being more vulnerable for treatment related complications.  相似文献   
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