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991.
Rationale, aims and objectives The transmission of research findings into routine care is a slow and unpredictable process. Important factors predicting receptivity for innovations within organizations have been identified, but there is a need for further research in this area. The aim of this study was to describe contextual factors and evaluate if organizational climate and implementation strategy influenced outcome, when a computer‐based concept for lifestyle intervention was introduced in primary health care (PHC). Method The study was conducted using a prospective intervention design. The computer‐based concept was implemented at six PHC units. Contextual factors in terms of size, leadership, organizational climate and political environment at the units included in the study were assessed before implementation. Organizational climate was measured using the Creative Climate Questionnaire (CCQ). Two different implementation strategies were used: one explicit strategy, based on Rogers’ theories about the innovation‐decision process, and one implicit strategy. After 6 months, implementation outcome in terms of the proportion of patients who had been referred to the test, was measured. Results The CCQ questionnaire response rates among staff ranged from 67% to 91% at the six units. Organizational climate differed substantially between the units. Managers scored higher on CCQ than staff at the same unit. A combination of high CCQ scores and explicit implementation strategy was associated with a positive implementation outcome. Conclusions Organizational climate varies substantially between different PHC units. High CCQ scores in combination with an explicit implementation strategy predict a positive implementation outcome when a new working tool is introduced in PHC.  相似文献   
992.
The relative importance of Haemophilus ducreyi and Treponema pallidum in genital ulcer disease in Africa has decreased recently, whereas that of herpes simplex virus (HSV) type 2 has increased. We analysed 301 lesional specimens from Tanzanian patients with genital ulcer disease for the presence of H. ducreyi, T. pallidum and HSV-1/HSV-2 by performing a separate PCR for each pathogen. Infectious agents were detected in 211 (70%) of the cases. A single pathogen was found in 191 samples and two or more pathogens in the remaining 20. HSV-2 represented 83% of all identified pathogens, HSV-1 8%, T. pallidum 4% and H. ducreyi 5%. HSV-1 was identified as a single pathogen in four samples, in combination with others in an additional 14 samples. Thus, HSV-1 can also be the cause of genital ulcer disease in Africa. Regular surveillance of genital ulcer disease aetiology is important in programs for management of genital ulcer disease and HIV in Africa.  相似文献   
993.
The immunoglobulin production capacities of peripheral blood lymphocytes obtained from patients with various chronic inflammatory liver diseases and from normal individuals were compared. Using a reverse hemolytic plaque assay, immunoglobulin-secreting cells (ISC) were counted immediately after isolation (immediate ISC) and again after 6-day, in vitro cultivation without stimulant (spontaneous ISC) or in the presence of pokeweed mitogen, PWM (PWM-induced ISC). An increased number of immediate ISC were observed in patients with chronic active hepatitis (CAH) of the autoimmune type (n = 7) or with CAH type B (n = 32), probably reflecting a defect of the in vivo suppressor cell system as previously demonstrated. In vitro preincubation of cells with 5 x 10(-8) M prednisolone reduced the increase in the number of immediate ISC in patients with CAH of the autoimmune type. On the other hand, lymphocytes obtained from patients with CAH-type NANB (n = 9) and with primary biliary cirrhosis (PBC) (n = 12) showed an impaired capacity to generate ISC upon stimulation with PWM. Spontaneous ISC from patients' lymphocytes were not significantly different from those of normal individuals. Using allogeneic co-cultures with lymphocytes from normal individuals and from patients with CAH NANB hepatitis or primary biliary cirrhosis, we observed no increase in suppressor cell activity. Therefore, the diminished responses to PWM are probably attributable to an alteration in the peripheral helper T-cell compartment.  相似文献   
994.
995.
We describe two patients with upper medullary infarctions showing ipsilateral facial weakness and relative sparing of the upper facial muscles. Electrophysiological follow-up using transcranial magnetic stimulation of the motor cortex in combination with stimulation of the peripheral facial nerve disclosed a supranuclear (corticofacial) tract lesion in one patient and a partial nuclear/infranuclear intra-axial facial nerve lesion in another. Received: 27 November 1998 Received in revised form: 27 January 1999 Accepted: 18 February 1999  相似文献   
996.
Addiction to nicotine is extremely challenging to overcome, and the intense craving for the next cigarette often leads to relapse in smokers who wish to quit. To dampen the urges of craving and inhibit unwanted behaviour, smokers must harness cognitive control, which is itself impaired in addiction. It is likely that craving may interact with cognitive control, and the present study sought to test the specificity of such interactions. To this end, data from 24 smokers were gathered using EEG and behavioural measures in a craving session (following a three‐hour nicotine abstention period) and a non‐craving session (having just smoked). In both sessions, participants performed a task probing various facets of cognitive control (response inhibition, task switching and conflict processing). Results showed that craving smokers were less flexible with the implementation of cognitive control, with demands of task switching and incongruency yielding greater deficits under conditions of craving. Importantly, inhibitory control was not affected by craving, suggesting that the interactions of craving and cognitive control are selective. Together, these results provide evidence that smokers already exhibit specific control‐related deficits after brief nicotine deprivation. This disruption of cognitive control while craving may help to explain why abstinence is so difficult to maintain.  相似文献   
997.
The ability of intraventricular infusion of apolipoprotein E (apoE) to reduce neuronal damage after global cerebral ischemia was investigated in apoE-deficient and wild-type mice. ApoE (5 microg/mL lipid-conjugated derived from human plasma; 1 microL/h, continuous infusion) significantly reduced neuronal damage in the caudate nucleus and CA2 pyramidal cell layer by approximately 50% in apoE-deficient mice after global ischemia compared to vehicle infusion. In wild-type mice infused with apoE, there was a trend for ischemic neuronal damage to be reduced. ApoE-infused mice had a marked reduction in 4-hydroxynonenal immunoreactivity, as a marker of lipid peroxidation. The results show that the presence of apoE at or after the time of injury can be neuroprotective, possibly via an anti-oxidant mechanism.  相似文献   
998.
A new migration assay, the time-lapse individual cell migration assay (TIM-assay), was developed, which allows the observation of cells over 24 h under controlled conditions. Using this technique, the migratory behavior of 8 human glioblastoma cell lines in vitro was studied. Special features are simultaneous documentation of migratory parameters of individual cells, i.e., migration velocities and migration paths of individual cells. Migration velocity for cell populations of the same cell line ranged from 0 to 24 μm/h. The migration paths were examined for being directional. Two thirds of all cells showed directional migration. Migration paths were further classified according to visual judgements for being linear, oscillating or mixed. The migration index had a mean of 91%. The presented TIM-assay allows the assessment of several new parameters, that may be useful to identify subgroups of gliomas with different biological characteristics. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
999.
1000.
The herbal remedies Natto K2, Agaricus, mistletoe, noni juice, green tea and garlic, frequently used by cancer patients, were investigated for their in vitro inhibition potential of cytochrome P‐450 3A4 (CYP3A4) metabolism. To our knowledge, only garlic and green tea had available data on the possible inhibition of CYP3A4 metabolism. Metabolic studies were performed with human c‐DNA baculovirus expressed CYP3A4. Testosterone was used as a substrate and ketoconazole as a positive quantitative inhibition control. The formation of 6‐β‐OH‐testosterone was quantified by a validated HPLC methodology. Green tea was the most potent inhibitor of CYP3A4 metabolism (IC50: 73 µg/mL), followed by Agaricus, mistletoe and noni juice (1324, 3594, >10 000 µg/mL, respectively). All IC50 values were high compared with those determined for crude extracts of other herbal remedies. The IC50/IC25 ratios for the inhibiting herbal remedies ranged from 2.15 to 2.67, indicating similar inhibition profiles of the herbal inhibitors of CYP3A4. Garlic and Natto K2 were classified as non‐inhibitors. Although Agaricus, noni juice, mistletoe and green tea inhibited CYP3A4 metabolism in vitro, clinically relevant systemic or intestinal interactions with CYP3A4 were considered unlikely, except for a probable inhibition of intestinal CYP3A4 by the green tea product. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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