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91.
BACKGROUND: Treatment options for allergic rhinitis include antihistamines, decongestants, anticholinergics, cromolyn sodium and corticosteroids. As the nose is a small organ, comprising less than 1% of total body mass and surface area, it seems logical to confine treatment of rhinitis to the diseased organ. OBJECTIVE: To evaluate the effects of therapy with intranasal fluticasone propionate (FP), both on subjective symptoms and pathophysiological mechanisms, in rhinitis patients during pollen season when the patients were symptomatic. METHODS: We used a double-blind, placebo (PLA)-controlled, randomized, double dummy, parallel group study of the effect of 6 weeks treatment. The double-blind comparison was made between the following three treatments: FP aqueous nasal spray, 200 microg taken once daily, levocabastine (LEV) nasal spray, 200 microg taken twice daily and PLA nasal spray. Clinical evaluation and the levels of cells and mediators in nasal washing were performed before and after treatments. Twenty-four patients (11 men and 13 women, aged 17-50 years, mean age 30.1 +/- 8.5) with strictly seasonal allergic rhinitis to Parietaria entered the study. Clinical evaluation and the levels of inflammatory cells (eosinophils and activated eosinophils, i.e. EG2+) and their mediators (tryptase, eosinophil cationic protein, eosinophil protein X and neutrophil myeloperoxidase) in nasal-lavage were performed before and after treatments. RESULTS: Treatment with FP significantly increased, with respect to placebo, the percentage of days without sneezing (P < 0. 001), nasal blockage (P < 0.001), rhinorrhea (P < 0.001), nasal itching (P < 0.001). Furthermore, treatment with FP showed additional benefits with respect to LEV. The percentage of days without nasal blockage was significantly higher in the FP group that in the placebo group (P = 0.018). The same applied to rhinorrhea (P = 0.009). The percentages of days without sneezing and itching were instead not significantly different between the two groups. As expected, no significant differences were observed in baseline medians of the rhinitis symptom scores as well as in mean values of all mediators and eosinophils in nasal lavages of the various groups under study. After treatment the mean of subjective symptoms as well as all values in nasal lavage level fell significantly only in the FP group, whereas no significant changes were observed either in LEV or PLA groups. Accordingly, significant differences were observed at the end of the treatments between the values of fluticasone group vs LEV and PLA group values. Significant correlations between these values and symptom scores were found, according with literature data suggesting a pathogenetic role for these mediators and eosinophils in rhinitis. CONCLUSION: FP (200 microg once daily) affords a significant degree of improvement in rhinitis control during pollen season, as measured by subjective and objective parameters, compared with LEV (200 microg twice daily) and PLA. The therapeutic benefits of intranasal FP are reflected in, and may be caused by, the decrease in nasal inflammatory cells.  相似文献   
92.
OBJECTIVE: To study acid-base status during a constant-load treadmill test at exercise levels close to the maximum lactate steady-state. DESIGN: Two tests were performed: one maximal and one steady-state at a load corresponding to the mean of the two ventilatory thresholds observed in the first test. SETTING: University Sports Science Laboratory. PARTICIPANTS: Twenty-three male Sports Science students, aged 26.7 (+/- 4.9 SD) years, 176.1 (+/- 6.3) cm in height, and weighing 72.8 (+/- 6.7) kg. MAIN OUTCOME MEASURES: Capillary blood gases, metabolites, electrolytes. RESULTS: Acid-base status variables declined significantly during the maximal test. Lactate concentrations were above the values observed at onset of blood lactate accumulation. All the blood variables did not vary significantly at the various experimental times, except pH values and PCO2 values. Bicarbonate concentration remained constant. Plasma potassium, chlorine and sodium concentration did not increase. CONCLUSION: During a steady-state test at a load corresponding to approximately 80% of VO2max, the acid-base status in capillary blood remained constant even though the lactate concentration was over 4 mmol/L. However, despite the maintenance of a constant acid-base status, other physiological variables did not behave in the same fashion.  相似文献   
93.
OBJECTIVES: The natural history of chronic hepatitis C and treatment response are different between blacks and Caucasians, but little comparable data is available about Latinos. METHODS: A cross-sectional secondary analysis to investigate differences between 421 anti-HCV-positive, treatment-na?ve, HCV-viremic Latinos and 2,510 Caucasians in 24 VA medical centers enrolled in a prospective study. RESULTS: Latinos were infected at a younger age and were less likely to have blood contact during combat, surgery, and needle stick injury, but were more frequently HIV coinfected (20.4%vs 3.9%, p < 0.0001) and prior HAV infection (39.9%vs 26.4%, p= 0.0001). Latinos were more likely to be treatment candidates, but less likely to actually initiate treatment. Liver histology (123 Latinos, 743 Caucasians) showed no difference in fibrosis or fibrosis rate, but steatosis (54.7%vs 43.2%, p= 0.038) was more common in Latinos. Eighty-eight Latinos and 481 Caucasians were subsequently treated with interferon-ribavirin: body mass index (BMI), duration of infection, baseline tests, liver histology and genotype distribution were similar. Compared with Caucasians, Latinos discontinued treatment prematurely more often (39.8%vs 28.9%, p= 0.043) and tended to have lower sustained virological response (SVR) rates (14.8%vs 22.5%, p= 0.10). Multivariate analysis found Latino race and history of recent alcohol use to be associated with early treatment discontinuation, whereas genotype and viral load but not ethnicity to be associated with SVR. CONCLUSIONS: Latinos were infected younger, more frequently HIV coinfected, more likely to meet criteria for antiviral therapy yet less likely to initiate treatment and had a trend toward lower SVR rates than Caucasians, but not in severity of liver disease. Latino ethnicity was associated with early discontinuation but not as an independent predictor of SVR.  相似文献   
94.
The DOTA macrocyclic ligand can form stable complexes with many cations besides yttrium and lutetium. For this reason, the presence of competing cationic metals in yttrium-90 and lutetium-177 chloride solutions can dramatically influence the radiolabeling yield. The aim of this study was to evaluate the coordination yield of yttrium- and lutetium-DOTATATE complexes when the reaction is performed in the presence of varying amounts of competing cationic impurities. In the first set of experiments, the preparation of the samples was performed by using natural yttrium and lutetium (20.4 nmol). The molar ratio between DOTATATE and these metals was 1 to 1. Metal competitors (Pb(2+), Zn(2+), Cu(2+), Fe(3+), Al(3+), Ni(2+), Co(2+), Cr(3+)) were added separately to obtain samples with varying molar ratio with respect to yttrium or lutetium (0.1, 0.5, 1, 2 and 10). The final solutions were analyzed through ultra high-performance liquid chromatography with an UV detector. In the second set of experiments, an amount of (90)Y or (177)Lu chloride (6 MBq corresponding to 3.3 and 45 pmol, respectively) was added to the samples, and a radio-thin layer chromatography analysis was carried out. The coordination of Y(3+) and Lu(3+) was dramatically influenced by low levels of Zn(2+), Cu(2+) and Co(2+). Pb(2+) and Ni(2+) were also shown to be strong competitors at higher concentrations. Fe(3+) was expected to be a strong competitor, but the effect on the incorporation was only partly dependent on its concentration. Al(3+) and Cr(3+) did not compete with Y(3+) and Lu(3+) in the formation of DOTATATE complexes.  相似文献   
95.
BACKGROUND: The aim of this study was to assess the long-term predictive values of supine bicycle exercise stress echocardiography (ESE), and the ESE additional role compared to other traditional clinical and rest echocardiographic variables, in 607 patients with low, intermediate and high pretest risk of cardiac events. METHODS: Clinical status and long-term outcome were assessed for a mean period of 46 months (range 12-60 months). ESE was performed for the diagnosis of suspected coronary artery disease (CAD) in 267 patients (43.9%), and for risk stratification of known CAD in 340 patients (56.1%). At baseline, the mean value of wall motion score index (WMSI) was 1.22 +/- 0.36, and the mean left ventricular ejection fraction was 58.5 +/- 10.9%. RESULTS: ESE was positive for ischemia in 210 patients (34.9%), while ECG was suggestive for ischemia in 157 patients (25.8%). During the test only 97 patients (15.9%) experienced angina. At peak effort, the mean WMSI was 1.38 +/- 0.46. A low workload was achieved by 158 patients (26.1%). During the follow-up period there were 222 events, including 82 hard events (36.9%), 48 deaths (21.6%) and 34 acute non-fatal myocardial infarction (15.3%). At stepwise multivariate model, cigarette smoking (p < 0.01), peak WMSI (p < 0.001), ESE positive for ischemia (p < 0.001) and low workload (p < 0.01) were the only independent predictors of cardiac death, while positive ESE, peak WMSI, angina during the test and hypercholesterolemia were the only independent determinants of hard cardiac events. The cumulative 5-year mean survival rate according to ESE response was 95.9% in patients with negative ESE, and 83.7% in patients with positive ESE (log rank 13.6; p < 0.00001). CONCLUSIONS: ESE yields prognostic information in known or suspected CAD, especially in patients with intermediate pretest risk level. The combined evaluation of clinical variables and other ESE variables, such as peak WMSI and exercise capacity, may further select patients at greatest risk of cardiac death in the overall population.  相似文献   
96.
BACKGROUND AND OBJECTIVES: Loss of heterozygosity (LOH) on the long arm of chromosome 7 (7q) has been frequently reported in several types of human cancer including hematologic malignancies. Moreover, monosomy of chromosome 7 and 7q deletions have been associated in acute myeloid leukemia (AML) with aggressive disease and poor prognosis. DESIGN AND METHODS: Using a panel of 11 polymorphic microsatellite markers at bands 7q21-q36, we investigated fifty patients (acute myeloid leukemia [AML], n=33 and acute lymphoid leukemia [ALL], n=17) for LOH, a hallmark of possible involvement of tumor suppressor genes. In parallel, the same acute leukemia (AL) cases were studied by conventional cytogenetics. RESULTS: A total of 48 spots of allelic loss were observed in 16 (32%) out of 50 patients (AML, n=11 and ALL, n=5). Among LOH+ve cases 3 showed chromosome 7 monosomies, whereas no cytogenetically detectable abnormalities were observed in chromosome 7 in the remaining 13. INTERPRETATION AND CONCLUSIONS: Comparison with karyotypic results indicated that presence of LOH at 7q21-q36 was significantly associated with other chromosomal aberrations. In fact, an altered karyotype was detectable in 87% of LOH+ve and in 52% of LOH(-ve) AL cases (p=0.024). In addition, LOH at 7q was prevalently associated with unfavorable cytogenetic lesions (p=0.013). Our study represents the first report of a significant association between LOH and recurrent chromosomal abnormalities in AL patients suggesting that the 7q21-q36, region may be an unstable area prone to chromosome breakage in patients with an abnormal karyotype.  相似文献   
97.
98.
Perineural cysts may be discovered incidentally on pelvic sonography and can easily mimic more common gynecologic masses. We report the complex cystic adnexal mass like appearance of these incidentally noted cysts which mimicked malignancy on sonography in a postmenopausal female, with stage I breast cancer and vaginal spotting. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound 2013  相似文献   
99.
Purpose: To evaluate the acquisition of AAC skills during an initial clinical trial and assess subsequent transfer of the training to the home setting. Method: A 12-year-old male with autism was first seen in a clinical setting to establish the use of a voice-output communication device. After learning to use the device to request access to preferred objects in the clinical trial, the intervention was transferred to the home. Follow-up with the parent was conducted via e-mail and telephone. Videotapes were made of initial home-based sessions to enable evaluation of the participant's progress. Results: The programme was successful in teaching the participant to use a portable AAC device to make requests during the clinical trial and then in two home-based activities. Conclusion: An initial clinical trial with follow-up support for parents may be an efficient method for beginning AAC intervention and transferring the training procedures to the home setting.  相似文献   
100.
The paper describes the carbohydrate, lipidic and nitrogen metabolism of the postoperative period which is subdivided into an early and a late phase. Since the metabolism of caloric substrates in the early postoperative period is a stress metabolism with glucose intolerance and wide protein catabolism, the authors emphasise that an insufficient caloric intake is worse than the fasting state and suggest that alternative caloric sources, such as branched chain amino acids, fatty acids and, even, ketonic bodies, should be used.  相似文献   
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