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111.
A longitudinal survey was conducted to investigate the presence of Brachyspira species in layer flocks. A total of 66 layer flocks kept in alternative husbandry systems were sampled at three time points: end of rearing, at peak of lay and at end of lay. Content from caecal samples of freshly killed birds was cultured at each sampling time point and processed for further investigations. Gross pathological lesions in caeca were recorded during post mortem investigation. Spirochaetes were isolated from 50 flocks: three flocks were positive at all three sampling points, 25 flocks at two and 22 flocks at one sampling point, respectively. The presence of Brachyspira spp. could not be related to specific gross pathological caecal lesions or antibiotic treatments. The number of positive flocks increased with the age of birds. Furthermore, organic flocks were more often positive than flocks from barn systems. In total 80 spirochaetal cultures were obtained. B. intermedia (43.8%) was the most common species, followed by B. pulli (13.8%) and B. pilosicoli (12.5%). Brachyspira murdochii and B. innocens were found in 5.0% and 2.5%, respectively, whereas 11.3% of Brachyspira isolates could not be identified to species level. In 11.3% of the samples mixed infections were detected. Finally, the longitudinal survey revealed for the first time a possible shift in the Brachyspira species in a substantial number (32%) of layer flocks during their lifetime.  相似文献   
112.
The current study investigated the influence of acute stress and the resulting cortisol increase on response inhibition and its underlying cortical processes, using EEG. Before and after an acute stressor or a control condition, 39 healthy men performed a go/no‐go task while ERPs (N2, P3), reaction times, errors, and salivary cortisol were measured. Acute stress impaired neither accuracy nor reaction times, but differentially affected the neural correlates of response inhibition; namely, stress led to enhanced amplitudes of the N2 difference waves (N2d, no‐go minus go), indicating enhanced response inhibition and conflict monitoring. Moreover, participants responding to the stressor with an acute substantial rise in cortisol (high cortisol responders) showed reduced amplitudes of the P3 of the difference waves (P3d, no‐go minus go) after the stressor, indicating an impaired evaluation and finalization of the inhibitory process. Our findings indicate that stress leads to a reallocation of cognitive resources to the neural subprocesses of inhibitory control, strengthening premotor response inhibition and the detection of response conflict, while concurrently diminishing the subsequent finalization process within the stream of processing.  相似文献   
113.
OFD1, now recognized as a ciliopathy, is characterized by malformations of the face, oral cavity and digits, and is transmitted as an X‐linked condition with lethality in males. Mutations in OFD1 also cause X‐linked Joubert syndrome (JBTS10) and Simpson–Golabi–Behmel syndrome type 2 (SGBS2). We have studied 55 sporadic and six familial cases of suspected OFD1. Comprehensive mutation analysis in OFD1 revealed mutations in 37 female patients from 30 families; 22 mutations have not been previously described including two heterozygous deletions spanning OFD1 and neighbouring genes. Analysis of clinical findings in patients with mutations revealed that oral features are the most reliable diagnostic criteria. A first, detailed evaluation of brain MRIs from seven patients with cognitive defects illustrated extensive variability with the complete brain phenotype consisting of complete agenesis of the corpus callosum, large single or multiple interhemispheric cysts, striking cortical infolding of gyri, ventriculomegaly, mild molar tooth malformation and moderate to severe cerebellar vermis hypoplasia. Although the OFD1 gene apparently escapes X‐inactivation, skewed inactivation was observed in seven of 14 patients. The direction of skewing did not correlate with disease severity, reinforcing the hypothesis that additional factors contribute to the extensive intrafamilial variability.  相似文献   
114.
115.
There is an increase in older-adult renal transplant recipients in United States. The objective of this study was to assess the association between physical function (PF) and patient survival in renal transplant recipients who are aged 65 years or older. Using United Network for Organ Sharing (UNOS) data from 2007 to 2016, renal transplant recipients aged 65 years or older were included. Multivariable Cox regression was used to assess associations between survival and functional status adjusted for age, sex, race, donor quality, diabetes, and dialysis vintage. The study identified 26,721 patients. Patient survival was significantly higher in recipients who needed no assistance and lowest in patients in need of total assistance (P < .0001). In deceased donor (DD) transplants, the relative risk for mortality was 2.06 (1.74-2.43) for total assistance and 1.17 (1.08-1.28) for moderate assistance compared to no assistance (P < .0001). In living donor (LD) transplants, the relative risk of mortality was 1.38 (0.78-2.42) for patients needing total assistance and 1.37 (1.14-1.65) for patients needing moderate assistance compared to patients who did not need assistance (0.003). PF is an independent predictor of post-transplant mortality. Assessment of older potential renal transplant recipients should include assessment and standardization of functional status to counsel about post-transplant survival.  相似文献   
116.
Despite several new urine markers urinary cytology remains the gold standard for the non-invasive detection of bladder carcinoma. The use of monoclonal antibodies against tumor associated antigens offers a promising approach to improve urinary cytology. The aim of this study was to compare fluorescence immunocytology (ImmunoCyt/Ucyt+ test), alone and in combination with the conventional cytology, with other urine markers. Urine samples from 126 patients undergoing cystoscopy were included in the study. Among them, 42 patients had urothelial carcinoma, two dysplasia, two other malignancies, and 78 had no evidence of bladder cancer. Urine samples were taken before any manipulation. We used the ImmunoCyt test and Papanicolaou staining for conventional cytology. The ImmunoCyt slides were examined under a fluorescence microscope. Evaluations of the tests were blinded to clinical and pathological data and were carried out by three independent observers. The results of cytology and ImmunoCyt were compared with the BTAstat, NMP22, Lewis X, 486p3/12, and Urovision tests. The sensitivity for the ImmunoCyt test was 78.3% and for conventional cytology 84.6%. The combination of ImmunoCyt and cytology showed a sensitivity of 89.1%. The specificity was 73.8% for the ImmunoCyt alone, 80.0% for the cytology, and 72.5% for the combination of ImmunoCyt and cytology. Sensitivities for the other tests were 68.8% for (FISH), 66.6% (BTA-Stat), 68.8% (486p3/12), 95.5% (Lewis X), and 71.1% for (NMP22). Specificity was 89.1% for (FISH), 78.2% (BTA-Stat), 76.4% (486p3/12), 32.8% (Lewis X), and 65.5% for (NMP22). Urinary cytology can be improved by immunostaining with monoclonal antibodies against tumor-associated antibodies. The combination of ImmunoCyt with conventional cytology offers a superior sensitivity to other commercial tests. The ImmunoCyt test provides a useful supplement to urinary cytology in the diagnosis of bladder cancer.M.I. Toma, M.G. Friedrich contributed equally to this study  相似文献   
117.
PURPOSE: To prospectively compare the protective effect of acetylcysteine, theophylline, and both agents combined in patients who are admitted to the intensive care unit with at least one risk factor for contrast material-induced nephropathy and who receive at least 100 mL of iodinated contrast medium. MATERIALS AND METHODS: Institutional ethics review board approval and informed consent were obtained. A total of 91 patients (mean age, 58.5 years+/-14.8 [standard deviation]; 31 women, 60 men; 150 examinations) were admitted to the intensive care unit with at least one risk factor for contrast-induced nephropathy and received either (a) 200 mg theophylline 30 minutes before contrast medium administration (group T), (b) 600 mg acetylcysteine twice daily on the day of and (if possible) the day before the examination (group A), or (c) both agents combined (group AT). The primary endpoint for this study was the incidence of contrast-induced nephropathy (chi2 test). RESULTS: Groups T, A, and AT were comparable with regard to baseline creatinine levels and the amount of contrast medium administered. The incidence of contrast-induced nephropathy in groups T, A, and AT was 2%, 12%, and 4%, respectively, and was significantly lower in group T than in group A (P=.047). There was no significant difference in the incidence of contrast-induced nephropathy between groups A and AT (P=.148) or between groups T and AT (P=.53). For group A, serum creatinine did not change after 12, 24, or 48 hours compared with baseline. Creatinine levels in group T decreased 12 hours (1.19 mg/dL+/-0.58; P=.008) and 48 hours (1.16 mg/dL+/-0.55; P=.034) after contrast material injection compared with baseline (1.25 mg/dL+/-0.61). In group AT, creatinine significantly decreased 24 hours (1.21 mg/dL+/-0.74; P=.003) and 48 hours (1.17 mg/dL+/-0.69; P<.001) after contrast material injection compared with baseline (1.28 mg/dL+/-0.74). Group A had significantly higher maximal increases in creatinine than groups T and AT (P=.014). CONCLUSION: For prophylaxis of contrast-induced nephropathy in patients who are admitted to the intensive care unit and who receive 100 mL or more of contrast medium, theophylline is superior to acetylcysteine.  相似文献   
118.
Purpose It is generally assumed that the biodistribution and pharmacokinetics of radiolabelled antibodies remain similar between dosimetric and therapeutic injections in radioimmunotherapy. However, circulation half-lives of unlabelled rituximab have been reported to increase progressively after the weekly injections of standard therapy doses. The aim of this study was to evaluate the evolution of the pharmacokinetics of repeated 131I-rituximab injections during treatment with unlabelled rituximab in patients with non-Hodgkins lymphoma (NHL).Methods Patients received standard weekly therapy with rituximab (375 mg/m2) for 4 weeks and a fifth injection at 7 or 8 weeks. Each patient had three additional injections of 185 MBq 131I-rituximab in either treatment weeks 1, 3 and 7 (two patients) or weeks 2, 4 and 8 (two patients). The 12 radiolabelled antibody injections were followed by three whole-body (WB) scintigraphic studies during 1 week and blood sampling on the same occasions. Additional WB scans were performed after 2 and 4 weeks post 131I-rituximab injection prior to the second and third injections, respectively.Results A single exponential radioactivity decrease for WB, liver, spleen, kidneys and heart was observed. Biodistribution and half-lives were patient specific, and without significant change after the second or third injection compared with the first one. Blood T1/2, calculated from the sequential blood samples and fitted to a bi-exponential curve, was similar to the T1/2 of heart and liver but shorter than that of WB and kidneys. Effective radiation dose calculated from attenuation-corrected WB scans and blood using Mirdose3.1 was 0.53+0.05 mSv/MBq (range 0.48–0.59 mSv/MBq). Radiation dose was highest for spleen and kidneys, followed by heart and liver.Conclusion These results show that the biodistribution and tissue kinetics of 131I-rituximab, while specific to each patient, remained constant during unlabelled antibody therapy. RIT radiation doses can therefore be reliably extrapolated from a preceding dosimetry study.  相似文献   
119.
OBJECTIVE: We studied the fate of the ipsilateral external carotid artery (ECA) after stenting of the internal carotid artery (ICA) compared with the contralateral ECA. SUBJECTS AND METHODS: One hundred twenty-one ipsilateral ECAs in 112 consecutive patients who underwent carotid artery Wallstent placement were prospectively studied with color-coded duplex sonographic scanning (CCDS) and compared with 83 contralateral ECAs over 2 years. CCDS was scheduled for the day before (day 0), the day after (day 1) and 3, 6, 12, and 24 months after stenting. Development of ECA occlusive disease was evaluated with ECA-common carotid artery flow ratio (peak systolic velocity). For estimation of ECA stenosis 70% or greater, flow ratio 4.1 was used as the cutoff point. RESULTS: Before and after stenting, two and three (one additional) ECA occlusions were seen. Median grade of ECA stenosis on day 1 did not significantly change at angiography (P = 1.0; tendency of increase) or CCDS (P =.27; tendency of decrease).At follow-up (day 1-24 months, CCDS only), frequency of stenosis 70% or greater in the ipsilateral ECA was 21 of 120 (17.5%) on day 1 and 41 of 107 (38.32%) at 24 months, and 3 of 107 (2.5%) and 5 of 107 (4.67%) ECA occlusions were registered at the two time points. Progression of disease, as demonstrated by increase in flow ratio over time, was much more pronounced in the ipsilateral ECAs compared with the contralateral ECAs (P =.0002).In stented ICA, 2 (1.85%) asymptomatic recurrent stenoses 70% or greater were found at CCDS.One of three patients with new ECA occlusions reported jaw claudication for 10 days. Perioperative stroke (one major, four minor) occurred in 5 of 121 patients (4.46%). Two minor strokes caused by embolization occurred during the first year. CONCLUSION: The more pronounced progression of arteriosclerotic disease at the orifice of the ipsilateral ECAs during the first year after carotid stenting might be due to local factors of the ICA stent. Its clinical significance in respect to the effect of the ECA as collateral supply to the brain might depend on the incidence of carotid stent rerecurrent stenosis, which was low in the present study.  相似文献   
120.
The mammalian startle reflex is a fast response to sudden intense sensory stimuli that can be increased by anxiety or decreased by reward. The cellular integration of sensory and modulatory information takes place in giant neurones of the caudal pontine reticular formation (PnC). The startle reflex is known to be enhanced by 5-hydroxytryptamine (5-HT); however, signalling mechanisms that change the excitability of the PnC giant neurones are poorly understood. Possible molecular candidates are two-pore-domain K+ (K2P) channels that generate a variable K+ background conductance and control neuronal excitability upon activation of G-protein-coupled receptors. We demonstrate by in situ hybridization that the K2P channel TASK-3 is substantially expressed in PnC giant neurones. Brain slice recordings revealed a corresponding background K+ current in these cells that forms about 30% of the outward current at −30 mV. Inactivation of TASK-3 at pH 6.4 and by ruthenium red depolarized the cells by about 7 mV and increased the action potential frequency as well as duration. Specific activation of Gαq-coupled 5-HT2 receptors with α-methyl 5-HT evoked a similar increase of neuronal excitability. Consistently, we measured afferent synaptic inputs from serotonergic raphe neurones and detected 5-HT2C receptors in PnC giant neurones by immunohistochemistry. Thus, neuronal excitability of PnC giant neurones in vivo is most likely increased by serotonergic projections via the K2P channel TASK-3.  相似文献   
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