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31.
Effects of physical activity on bone properties, when controlled for genetic effects, are not fully understood. We aimed to study the association between long‐term leisure time physical activity (LTPA) and bone properties using twin pairs known to be discordant for leisure time physical activity for at least 30 yr. Volumetric BMD and geometric properties were measured at the tibia shaft and distal end using pQCT in 16 middle‐aged (50–74 yr) same‐sex twin pairs (seven monozygotic [MZ] and nine dizygotic [DZ] pairs) selected from a population‐based cohort. Paired differences between active and inactive co‐twins were studied. Active members of MZ twin pairs had larger cortical bone cross‐sectional area (intrapair difference: 8%, p = 0.006), thicker cortex (12%, p = 0.003), and greater moment of inertia (Imax, 20%, p = 0.024) at the tibia shaft than their inactive co‐twins. At the distal tibia, trabecular BMD (12%, p = 0.050) and compressive strength index (18%, p = 0.038) were also higher in physically active MZ pair members than their inactive co‐twins. The trends were similar, but less consistently so, in DZ pairs as in MZ pairs. Our genetically controlled study design shows that LTPA during adulthood strengthens bones in a site‐specific manner, that is, the long bone shaft has a thicker cortex, and thus higher bending strength, whereas the distal bone has higher trabecular density and compressive strength. These results suggest that LTPA has a potential causal role in decreasing the long‐term risk of osteoporosis and thus preventing osteoporotic fractures.  相似文献   
32.
We previously showed cell–cell contacts of human dermal fibroblasts to induce expression of the hepatocyte growth factor/scatter factor (HGF) in a process designated as nemosis. Now we report on nemosis initiation in bone marrow mesenchymal stem cells (BMSCs). Because BMSCs are being used increasingly in cell transplantation therapy we aimed to demonstrate a functional effect and benefit of BMSC nemosis for wound healing. Nemotic and monolayer cells were used to stimulate HaCaT keratinocyte migration in a scratch-wound healing assay. Both indicators of nemosis, HGF production and cyclooxygenase-2 expression, were induced in BMSC spheroids. When compared with a similar amount of cells as monolayer, nemotic cells induced keratinocyte in vitro scratch-wound healing in a concentration-dependent manner. The HGF receptor, c-Met, was rapidly phosphorylated in the nemosis-stimulated keratinocytes. Nemosis-induced in vitro scratch-wound healing was inhibited by an HGF-neutralizing antibody as well as the small molecule c-Met inhibitor, SU11274. HGF-induced in vitro scratch-wound healing was inhibited by PI3K inhibitors, wortmannin and LY294002, while LY303511, an inactive structural analogue of LY294002, had no effect. Inhibitors of the mitogen-activated protein kinases MEK/ERK1/2 (PD98059 and U0126), and p38 (SB203580) attenuated HGF-induced keratinocyte in vitro scratch-wound healing. We conclude that nemosis of BMSCs can induce keratinocyte in vitro scratch-wound healing, and that in this effect signaling via HGF/c-Met is involved.  相似文献   
33.

Objective

To compare the systemic effects in burn and non-burn patients undergoing skin grafting with or without the use of topical epinephrine to control bleeding.

Background

The effects of topical epinephrine on haemodynamics and bleeding are principally documented with burn patients. No reports are available on the effects of topical epinephrine on non-burn patients especially on markers of tissue perfusion.

Material and methods

A prospective study where topical epinephrine was used on burn and non-burn patients and five patients served as controls without epinephrine usage. Catecholamine concentrations were measured and to estimate the systemic effects of epinephrine, serum lactate and pyruvate concentrations were analyzed and perioperative haemodynamic changes recorded.

Results

Compared to the baseline values, there was a significant increase in the heart rate, serum epinephrine and lactate concentrations and LP-ratios in the burn patients and an increase in the epinephrine concentrations in the non-burn patients at 1 and 2 h. Epinephrine and lactate concentrations and LP-ratios were also higher in the burn patients compared to the other groups. Altogether, there were no changes in the control group.

Conclusion

This study showed that the use of topical epinephrine has systemic effects on haemodynamics and serum epinephrine concentrations. Increased epinephrine concentrations in burn patients suggest increased absorption properties in these patients. The increased lactate concentrations and LP-ratios suggest tissue ischaemia, likely in skin.  相似文献   
34.
OBJECTIVE: The necessity of operative treatment of endotension after endovascular grafting of abdominal aortic aneurysms (endovascular aneurysm repair; EVAR) is under debate. The proposed causes of endotension and related treatment protocols are controversial. We report the outcome of a nonoperative approach to five patients with endotension after EVAR. METHODS: From February 1997 to August 2004, 160 patients who underwent EVAR of an infrarenal abdominal aortic aneurysm were evaluated for the incidence of endotension. According to the endovascular protocol, plain radiographs, spiral computed tomography, and angiography were performed before and after surgery for follow-up. To detect endotension, spiral computed tomography was performed by using a delayed imaging technique after the infusion of contrast medium. Endotension was defined as an aneurysm sac enlargement after EVAR without evidence of endoleak. Aneurysm sac rupture was defined as discontinuity of the calcific rim of the aneurysmal sac and the presence of intra-aneurysmal fluid outside the sac. RESULTS: We found five (3.1%) patients with endotension. Three of these experienced aneurysmal sac rupture. Only one of the three was underwent operation on experiencing sudden intestinal occlusion due to intra-abdominal adhesions. This patient had no intra-abdominal or retroperitoneal bleeding or hematoma but died after intensive care as a result of non-aneurysm-related problems. Four patients with endotension are still being closely followed up according to our surveillance protocol, and they are doing clinically well. After rupture, clear shrinking of the aneurysm sac was seen in two patients. CONCLUSIONS: Endotension after EVAR may cause subsequent aneurysm rupture. Endotension is evidently not associated with endoleak I to III provided that the endovascular graft is maintained in appropriate position and that free endovascular flow is observed. We propose to consider a nonoperative approach in the clinically asymptomatic patient with aneurysm enlargement after EVAR if endoleak is excluded by well-performed imaging techniques.  相似文献   
35.
We present the details of three children with hypercalcemia-induced acute kidney injury (AKI). After traditional therapy with fluids, loop diuretics, steroids and calcitonin had failed to correct the hypercalcemia, they were given treatment with low doses of intravenous (i.v.) pamidronate, which resulted in normalization of serum calcium and kidney function. In one child Doppler renal ultrasound revealed dampened arterial blood flow, which resolved with normalization of serum calcium. On the basis of cumulative data and our experience, we suggest that i.v. application of bisphosphonates be moved from the second to the first line of treatment of hypercalcemic AKI.  相似文献   
36.
OBJECTIVE: To assess the impact of postoperative continuous pleural lavage (PCPL) after thoracotomy for the treatment of stage 2 pleural empyema in relation to postoperative length of stay and morbidity. METHODS: Stage 2 pleural empyema was diagnosed with computer tomography. Conservative treatment including antibiotics and pleural aspiration was introduced. 89 patients treated for stage 2 pleural empyema by thoracotomy, pleural discharge evacuation and irrigation after pleural decortication were identified after unsuccessful conservative treatment for 10 days. Whenever pleural discharge remained opaque after operation, PCPL was administered daily through the cranial chest tube and discharge evacuated through the caudal pleural suction (10-15 mmHg) tube. Risk factors related to pleural pus and patient outcome were sought for. RESULTS: Seventy-seven out of 89 patients (86.5%) had clear empyema discharge immediately after pleural decortication and irrigation. Pleural discharge remained opaque despite surgery in 12 out of 89 patients (13.5%) and PCPL was introduced. Presence of a combination of risk factors for pleural empyema, such as dental caries, alcohol abuse or previous inflammatory reaction, was predictive for persistence of opaque pleural discharge after operation (P<0.05). Need for re-thoracotomies (in 11 cases, P=ns) and postoperative deaths (P<0.05) were related with patients who did not have PCPL. The length of the hospital treatment was 20.1+/-3.1 (days+/-SEM) among patients with PCPL and 19.2+/-1.8 without PCPL before possible re-thoracotomy, respectively (P=ns). CONCLUSIONS: Early postoperative (1 day-11 months) mortality was statistically associated with patients having fibrinopurulent empyema but no PCPL. PCPL is a feasible method to clear pleural pus discharge without prolongation of hospitalization and may be recommended after thoracotomy for patients with fibrinopurulent stage 2 empyema.  相似文献   
37.
The attitudes of patients toward resident participation in a university-based dermatology outpatient clinic were evaluated. Of 206 patients asked to participate, 191 patients completed the self-administered questionnaire (92.7%). The overwhelming majority of patients (99.5%) were satisfied (81.8% "very satisfied" and 17.7% "satisfied") with the resident's participation in their care. Many more patients expressed a willingness to allow residents to take histories (93.6%), perform physical examinations (87.2%), and counsel on preventive measures (74.5%), than to allow surgical excisions of skin cancers (19.7%), perform skin biopsies (43.6%), or prescribe medications (44.7%). Of respondents to the questionnaire, 83.2% self-reported an understanding of the difference between "resident" and "attending" physicians. However, only 31.3% (95% confidence interval 24.5-38.1) were able to broadly categorize the amount of training completed by dermatology residents. Dermatology resident participation in outpatient clinics is essential to quality dermatologic education. Consistent with the results of prior studies in other medical disciplines, our study demonstrated an overwhelming patient satisfaction with the participation of dermatology residents in their care.  相似文献   
38.
Digestive Diseases and Sciences - Inadequate bowel preparation (IBP) is associated with reduced adenoma detection. However, limited research has examined the impact of different commercial bowel...  相似文献   
39.
40.
Digestive Diseases and Sciences - Severe and fulminant Clostridioides difficile infection (CDI) is associated with significant morbidity and mortality. While fecal microbiota transplantation (FMT)...  相似文献   
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