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71.

INTRODUCTION

The aims of this study were to audit results of a 10-year experience of surgery for acute limb ischaemia (ALI) in terms of limb salvage and mortality rates, and to compare results with a historical published series from our unit.

PATIENTS AND METHODS

All emergency operations performed during the period 1993–2003 were identified from theatre registers and patient notes reviewed to determine indications for, and outcome of, surgery. Data were compared to a similar cohort who underwent surgery from 1980 to 1990.

RESULTS

There was a 33% increase in workload from 87 to 116 patients between the two time periods. The number of patients with idiopathic ALI reduced (24% versus 4%; P < 0.05), and there were fewer smokers (71% versus 39%; P < 0.05) and a greater number of claudicants (17% versus 35%; P < 0.05) in those treated from 1993–2003. Latterly, more patients underwent pre-operative heparinisation (33% versus 80%; P < 0.05), received prophylactic antibiotics (14% versus 63%; P < 0.05), and had anaesthetic presence in theatre (46% versus 88%; P < 0.05). There was also a reduction in local anaesthetic procedures (80% versus 41%; P < 0.05). Despite increased pre-operative (15% versus 47%; P < 0.05) and on-table imaging (0% versus 16%; P < 0.05) technical success did not improve. Whilst complication rates were identical at 62%, there were fewer cardiovascular complications in the recent cohort. The 30-day mortality rate for embolectomy fell from 45% to 33%. Multivariate analysis revealed age > 70 years, prolonged symptom duration, ASA score ≥ III, lack of prophylactic antibiotics, absence of an anaesthetist, and operations performed under local anaesthetic to be associated with increased risk of mortality. Factors adversely affecting limb salvage included prolonged duration from symptom onset to operation, and a history of claudication or smoking.

CONCLUSIONS

Despite improvements in pre- and peri-operative management, arterial embolectomy/thrombectomy remains a procedure with a high morbidity and mortality. Further attempts to improve outcome must be directed at early diagnosis and referral as delay from symptom onset to surgery is a major determinant of outcome.  相似文献   
72.
IntroductionDaily and event‐driven PrEP are both efficacious in reducing the risk for HIV infection. However, the practice of event‐driven PrEP (edPrEP) is less well studied, in particular when provided as an alternative to daily PrEP. We studied regimen preferences and switches, and sexually transmitted infection (STI) incidence.MethodsWe analysed pooled data from two prospective cohort studies among MSM: Be‐PrEP‐ared, Belgium and AMPrEP, the Netherlands. In both projects, participants could choose between daily and edPrEP at three‐monthly study visits, when they were also screened for sexually transmitted infections including hepatitis C (HCV). We assessed the proportion choosing each regimen, and the determinants of choosing edPrEP at baseline. Additionally, we compared the incidence rates (IRs) of HCV, syphilis and chlamydia or gonorrhoea between regimens using Poisson regression. The study period was from 3 August 2015 until 24 September 2018.Results and discussionWe included 571 MSM, of whom 148 (25.9%) chose edPrEP at baseline. 31.7% of participants switched regimen at least once. After 28 months, 23.5% used edPrEP. Older participants (adjusted odds ratio (aOR) = 1.38 per 10 years, 95% confidence interval (CI) = 1.15 to 1.64) and those unemployed (aOR = 1.68, 95% CI = 1.03 to 1.75) were more likely to initially choose edPrEP. IR of HCV and syphilis did not differ between regimens, but the IR of chlamydia/gonorrhoea was higher among daily users (adjusted incidence rate ratio = 1.61, 95% CI = 1.35 to 1.94).ConclusionsA quarter of participants chose edPrEP at baseline and at 28 months this proportion was similar. Although the IR of HCV and syphilis were similar in the two regimens, the lower incidence of chlamydia and gonorrhoea among edPrEP users may suggest that less frequent STI testing of this group could be considered.  相似文献   
73.
Angiogenesis is an important process for forming new blood vessels. It is fundamental in many biological processes including development, reproduction and wound repair. Under these conditions, angiogenesis is a highly regulated process. Numerous inducers of angiogenesis have been identified, including the members of the vascular endothelial growth factor family, angiopoietins, transforming growth factors, platelet-derived growth factor, tumor necrosis factor-alpha, interleukins and members of the fibroblast growth factor family. Vascular endothelial growth factor-A is the most potent pro-angiogenic protein described to date. It induces proliferation, sprouting and tube formation of endothelial cells. Angiogenesis is therefore a putative target for therapy. The potential application of different angiogenesis inhibitors is currently under intense clinical investigation. A better understanding of the biology of angiogenesis may reveal new targets for treating many diseases that are associated with this complex process. In this review, we summarize the most important molecular mechanisms mediating angiogenesis.  相似文献   
74.

Background and purpose:

Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.

Experimental approach:

Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.

Key results:

Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.

Conclusion and implications:

Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1.  相似文献   
75.
76.
Acute generalized exanthematous pustulosis due to thallium   总被引:4,自引:0,他引:4  
Acute generalized exanthematous pustulosis (AGEP) is characterized clinically by fever, pruritus and acute pustular eruption. Usually a drug is found to be the responsible agent. We present a patient who experienced an acute generalized exanthematous pustulosis due to radioactive thallium. The eruption cleared rapidly after discontinuation of the drug and systemic corticosteroid therapy.  相似文献   
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79.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  相似文献   
80.
Cadmium is a toxic heavy metal element, which probably cause infertility by impairment in spermatogenesis. The present work aimed (i) to study the toxic effect of cadmium on spermatogenesis in rat, as well as (ii) the protective effect of Crocus sativus L. on cadmium‐intoxicated rats. Cadmium chloride was administered intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. Crocus sativus L. was pre‐treated in both of control and cadmium‐injected rats. Animals were sacrificed on day 17 after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank's balanced salt solution for the evaluation of sperm count and viability, and left testis was fixed in 10% formalin for histological evaluation. Following contamination with cadmium, a decrease was observed in the number and viability of cauda epididymis sperm, which were increased by Crocus sativus L. pre‐treatment (P < 0.05). In addition, cadmium decreased both cell proliferation and Johnsen Scores in the seminiferous tubules, which were reversed by Crocus sativus pre‐treatment (P < 0.05). Furthermore, cadmium‐induced decrease in the amount of free serum testosterone as well as an increase in lipid peroxidation activity in the testicular tissue was reversed by Crocus sativus L. (P < 0.05). These findings may support the concept that Crocus sativus L. can improve the cadmium toxicity on spermatogenesis.  相似文献   
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