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91.
Neutropenic fever is an important cause of morbidity and mortality during therapy of acute myeloid leukemia. Patients with acute myeloid leukemia are at increased risk of acquiring vancomycin resistant enterococcal infection and its treatment remains problematic. Vancomycin therapy for more than 7 days is usually associated with inducible vancomycin-resistant enterococcal infections. We report a case of vancomycin resistant enterococcal sepsis in a patient of acute myeloid leukemia.  相似文献   
92.
The hippocampus is a prominent structure to study mechanisms of learning and memory at the cellular level. Long-term potentiation (LTP) as well as long-term depression (LTD) are the major cellular models which could underlie learning and memory formation. LTP and LTD consist of at least two phases, an early protein synthesis-independent transient stage (<4 h; E-LTP, E-LTD) as well as a prolonged phase (>4 h; L-LTP, L-LTD) requiring the synthesis of new proteins. It is known that during E-LTP the further induction of longer lasting LTP is precluded. However, if E-LTP is transformed into L-LTP, the same synapses now allow the induction of LTP again. We reproduced the LTP-results first and then investigated whether hippocampal LTP or LTD also prevents the establishment of subsequent LTD-induction in the same synaptic input. We show that the prior induction of LTP or LTD does not prevent a short-term depression (STD) but occludes LTD in apical dendrites of CA1 neurons in hippocampal slices in vitro during the early phase of LTP or LTD. However, LTD can again be induced in addition to STD after the establishment of L-LTP or L-LTD, that is about 4 h after the induction of the first event in the same synaptic input. We suggest that the neuronal input preserves the capacity for STD immediately after an initial potentiation or depression, but for the onset of additional longer lasting LTD in the same synaptic input, the establishment of the late plasticity form of the preceding event is critical.  相似文献   
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BACKGROUND: An estimated 25-40 million of the 127 million people of Bangladesh have been exposed to high levels of naturally occurring arsenic from drinking groundwater. The mitigating effects of diet on arsenic-related premalignant skin lesions are largely unknown. OBJECTIVES: The purpose of this study was to clarify the effects of the vitamin B group (thiamin, riboflavin, niacin, pyridoxine, and cobalamin) and antioxidants (vitamins A, C, and E) on arsenic-related skin lesions. METHODS: We performed a cross-sectional study using baseline data from the Health Effects of Arsenic Longitudinal Study (HEALS), 2000-2002, with individual-level, time-weighted measures of arsenic exposure from drinking water. A total of 14,828 individuals meeting a set of eligibility criteria were identified among 65,876 users of all 5,996 tube wells in the 25-km(2) area of Araihazar, Bangladesh; 11,746 were recruited into the study. This analysis is based on 10,628 subjects (90.5%) with nonmissing dietary data. Skin lesions were identified according to a structured clinical protocol during screening and confirmed with further clinical review. RESULTS: Riboflavin, pyridoxine, folic acid, and vitamins A, C, and E significantly modified risk of arsenic-related skin lesions. The deleterious effect of ingested arsenic, at a given exposure level, was significantly reduced (ranging from 46% reduction for pyridoxine to 68% for vitamin C) for persons in the highest quintiles of vitamin intake. CONCLUSIONS: Intakes of B-vitamins and antioxidants, at doses greater than the current recommended daily amounts for the country, may reduce the risk of arsenic-related skin lesions in Bangladesh.  相似文献   
96.

Aims

The aim of this prospective study is to elucidate feasibility of protocol of neoadjuvant concomitant radiochemotherapy with capecitabine and long course radiotherapy with subsequent laparoscopic rectal resection. We assessed treatment toxicity, downstaging rate, pathological response to the neoadjuvant treatment, surgery complications, rate of conversions and sphincter-preserving surgical procedures, and intraoperative and early postoperative complications too.

Methods

We acquired data of 78 patients from 1 January 2005 to 31 December 2007 with a locally advanced rectal cancer in our study. All patients were indicated for the neoadjuvant concomitant chemoradiotherapy due to locally advanced tumor (T3 or T4) or lymph nodes involvement suspicion (N+). Both radiotherapy (to pelvic region) and chemotherapy (capecitabine) were administered. Rectal tumors were localized within 12 cm from the anocutaneous verge. The average follow-up time was 23.9 months.

Results

All patients completed their treatment according to the planned regimen and dose. The surgery was performed laparoscopicaly within 4–8 weeks following the concomitant chemoradiotherapy – in 17% cases was converted into conventional surgery. Downstaging was achieved in 69% of patients, pathological complete response in 10%, histologically negative lymph nodes were documented in 58% of patients. Grade 3 toxicity of the concomitant chemoradiotherapy was present in 3%; grade 2 in 29% of patients, particularly skin and gastrointestinal form. Intraoperative and early postoperative complications of the surgery were 18%. Re-operation was needed in 5% cases.

Conclusions

We demonstrated safety and low toxicity of the concomitant chemoradiotherapy with capecitabine.  相似文献   
97.
Arsenic exposure and anemia in Bangladesh: a population-based study   总被引:1,自引:0,他引:1  
OBJECTIVE: The purpose of this study was to examine the association between arsenic exposure and anemia, based on blood hemoglobin concentration. METHODS: Hemoglobin measures, skin lesions, arsenic exposure, and nutritional and demographic information were collected from 1954 Bangladeshi participants in the Health Effects of Arsenic Longitudinal Study. We used general linear modeling to assess the association between arsenic exposure and hemoglobin concentration, examining men and women separately. RESULTS: Arsenic exposure (urinary arsenic >200 microg/L) was negatively associated with hemoglobin among all men and among women with hemoglobin <10 d/L. Other predictors of anemia in men and women included older age, lower body mass index, and low intake of iron. Among women, the use of contraceptives predicted higher hemoglobin. CONCLUSIONS: The study suggests an association between high arsenic exposure and anemia in Bangladesh.  相似文献   
98.
Bisphenol A (BPA), an estrogenic and endocrine disrupting agent, is widely used in manufacturing of polycarbonate plastics and epoxy resins. BPA and other endocrine disrupting chemicals (EDCs) act via multiple mechanisms including interference with mitochondrial functions. Mitochondria are the hub of cellular energy pool and hence are the target of many EDCs. We studied perturbation of activities of mitochondrial enzymes by BPA and its possible role in hepatotoxicity in Wistar rats. Rats were exposed to BPA (150 mg/kg, 250 mg/kg, 500 mg/kg per os, for 14 days) and activities of enzymes of mitochondrial electron transport chain (ETC) were measured. Besides, other biochemical parameters such as superoxide generation, protein oxidation, and lipid peroxidation (LPO) were also measured. Our results indicated a significant decrease in the activities of enzymes of mitochondrial ETC complexes, i.e., complex I, II, III, IV, and V along with significant increase in LPO and protein oxidation. Additionally, a significant increase in mitochondrial superoxide generation was also observed. All these findings could be attributed to enhanced oxidative stress, decrease in reduced glutathione level, and decrease in the activity of superoxide dismutase in rat liver mitochondria isolated from BPA‐treated rats. BPA treatment also caused a significant increase in serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase indicating its potential hepatotoxicity. Furthermore, histopathological findings revealed marked edema formation, hepatocellular degeneration, and necrosis of liver tissue in BPA‐exposed rats. In conclusion, this study provides an evidence of impaired mitochondrial bioenergetics and liver toxicity after high‐dose BPA exposure in rats. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1922–1934, 2016.  相似文献   
99.
Immunomodulatory activity of aqueous extract of Trigonella foenum graecum L., a widely used medicinal and dietary herb, was evaluated in male Swiss albino mice. Mice were treated with three doses of extract (50, 100 and 250 mg/kg body weight per os) for 10 days. Body weight, relative organ weight, cellularity of lymphoid organs, delayed type of hypersensitivity (DTH) response, plaque-forming cell (PFC) assay, haemagglutination titre (HT), quantitative haemolysis of SRBC (QHS) assay, phagocytosis, and lymphoproliferation were studied in various groups of animals. At doses of 50 and 100 mg/kg, a significant increase (p < 0.05) in relative organ weight of thymus was observed but there was no effect on kidney and spleen weights. Liver weight also increased significantly at doses of 100 and 250 mg/kg. However, no elevation in the levels of liver function test (LFT) enzymes was observed. As regards lymphoid organ cellularity, spleen recorded no significant increase at any dose, whereas cellularities of thymus and bone marrow were significantly increased. T. foenum graecum extract elicited a significant (p < 0.001) increase in the DTH response at doses of 50 and 100 mg/kg, but the change at higher dose of 250 mg/kg was not statistically significant. Humoral immunity as measured by PFC showed an elevated response at a dose of 100 mg/kg, but at 50 and 250 mg/kg, no significant effect was observed. In the HT test, plant extract also showed modulatory effect at all the doses. Plant extract elicited a significant increase in phagocytic index and phagocytic capacity of macrophages. Stimulatory response of plant extract was also observed in lymphoproliferation assay but the response was weak. Overall, T. foenum graecum showed a stimulatory effect on immune functions in mice. As it is used for a variety of medicinal purposes, its immunostimulatory effect, as reported in this study, strengthens the rationale of its use in several Ayurvedic and Unani drugs.  相似文献   
100.
AIM: TO evaluate the incidence of contrast-induced nephropathy (CIN) in cirrhotic patients and to identify risk factors for the development of CIN.
METHODS: We performed a retrospective review of 216 consecutive patients with cirrhosis who underwent computed tomography (CT) with intravenous contrast at the University of Rochester between the years 2000-2005. We retrospectively examined factors associated with a high risk for CIN, defined as a decrease in creatinine clearance of 25% or greater within one week after receiving contrast.
RESULTS: Twenty-five percent of our patients developed CIN, and 74% of these patients had ascites seen on CT. Of the 75% of patients who did not develop CIN, only 46% had ascites. The presence of ascites was a significant risk factor for the development of CIN (P = 0.0009, OR 3.38, 95% CI 1.55-7.34) in multivariate analysis. Patient age, serum sodium, Model for End-stage Liver Disease score, diuretic use, and the presence of diabetes were not found to be significant risk factors for the development of CIN. Of the patients who developed CIN, 11% developed chronic renal insufficiency, defined as a creatinine clearance less than baseline for 6 wk.
CONCLUSION: Our results suggest that in hospitalized cirrhotic patients, especially those with ascites, the risk of CIN is substantial.  相似文献   
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