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41.
BackgroundRoux-en-Y gastric bypass surgery is the leading surgical treatment of morbid obesity in the United States. The role of preoperative weight loss in gastric bypass surgery remains controversial. We performed a prospective randomized trial to determine whether preoperative weight loss results in better outcomes after laparoscopic gastric bypass.MethodsA total of 100 patients undergoing laparoscopic gastric bypass surgery from May 2004 to October 2005 were randomized preoperatively to either a weight loss group with a 10% weight loss requirement or a group that had no weight loss requirements. The patients were followed prospectively. The variables analyzed included perioperative complications, operative time, postoperative weight loss, and resolution of co-morbidities.ResultsData were available for 26 patients in the weight loss group and 35 in the nonweight loss group. The 2 groups had similar preoperative characteristics, conversion and complication rates, and resolution of co-morbidities. The initial body mass index was 48.7 kg/m2 and 49.3 kg/m2 for the weight loss group and nonweight loss group, respectively (P = NS). The preoperative body mass index was 44.5 kg/m2 and 50.7 kg/m2 for the weight loss group and nonweight loss group, respectively (P = 0.0027). The operative time was 220.2 and 257.6 minutes for the 2 groups (P = 0.0084). The percentage of excess weight loss at 3 and 6 months for the weight loss group and nonweight loss group was 44.1% and 33.1% (P = 0.0267) and 53.9% and 50.9% (P = NS), respectively. The interval to surgery from the initial consultation was 5.4 months and 5.2 months for the 2 groups (P = NS).ConclusionsPreoperative weight loss before laparoscopic Roux-en-Y gastric bypass was associated with a decrease in the operating room time and an improved percentage of excess weight loss in the short term. Preoperative weight loss, however, did not affect the major complication or conversion rates, and its long-term effects were not apparent through this study. Also, preoperative weight loss did not have any bearing on the resolution of co-morbidities.  相似文献   
42.
Bisphosphonates are widely used for the treatment of bone diseases associated with increased osteoclastic bone resorption. Bisphosphonates are known to inhibit biochemical markers of bone formation in vivo, but it is unclear to what extent this is a consequence of osteoclast inhibition or a direct inhibitory effect on cells of the osteoblast lineage. In order to investigate this issue, we studied the effects of various bisphosphonates on osteoblast growth and differentiation in vitro. The aminobisphosphonates pamidronate and alendronate inhibited osteoblast growth, caused osteoblast apoptosis, and inhibited protein prenylation in osteoblasts in a dose-dependent manner over the concentration range 20-100 microM. Further studies showed that alendronate in a dose of 0.1 mg/kg inhibited protein prenylation in calvarial osteoblasts in vivo, indicating that alendronate can be taken up by osteoblasts in sufficient amounts to inhibit protein prenylation at clinically relevant doses. Pamidronate and alendronate inhibited bone nodule formation at concentrations 10-fold lower than those required to inhibit osteoblast growth. These effects were not observed with non-nitrogen-containing bisphosphonates or with other inhibitors of protein prenylation and were only partially reversed by cotreatment with a fourfold molar excess of ss-glycerol phosphate. We conclude that aminobisphosphonates cause osteoblast apoptosis in vitro at micromolar concentrations and inhibit osteoblast differentiation at nanomolar concentrations by mechanisms that are independent of effects on protein prenylation and may be due in part to inhibition of mineralization. While these results need to be interpreted with caution because of uncertainty about the concentrations of bisphosphonates that osteoblasts are exposed to in vivo, our studies clearly demonstrate that bisphosphonates exert strong inhibitory effects on cells of the osteoblast lineage at similar concentrations to those that cause osteoclast inhibition. This raises the possibility that inhibition of bone formation by bisphosphonates may be due in part to a direct inhibitory effect on cells of the osteoblast lineage.  相似文献   
43.
Over the last 6 years, a health care program aimed at the surgical correction of postburn contractures has taken place in Faridpur, Bangladesh. People in this rural region are very poor and often cannot afford medical treatment. Often secondary flexion contractures of the face and chin as well as the upper and lower extremity impede daily functioning and have an enormous psycho-social impact. The application of basic plastic surgical principles such as local transposition of skin flaps as well as skin grafts restores function dramatically and results in stable skin cover. It is quite challenging - both for the surgeon and the anaesthesiologist - to perform these operations within a rather limited infrastructure. In Bangladesh, there is a monumental need for correction of postburn contractures for the social needs of the patient as well as for functional purposes. Future actions should be directed to the training of surgeons and the development of specialized hospitals to demonstrate social as well as political commitment to health care programs.  相似文献   
44.

Background  

Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders.  相似文献   
45.
This study investigated the relationship between imagery function and individual perceptions of collective efficacy as a function of skill level. Elite (n = 70) and non elite (n = 71) athletes from a number of interactive team sports completed the Sport Imagery Questionnaire (SIQ) and the Collective Efficacy Inventory (CEI). Multiple hierarchical regression analysis was then used to examine which SIQ sub-scales predicted individual perceptions of collective efficacy. For the elite sample, Motivational General-Mastery (MG-M) imagery accounted for approximately 17% of the variance in collective efficacy scores. No significant predictions were observed in the non elite sample. The findings suggest MG-M imagery as a potential technique to improve levels of collective efficacy although competitive level may moderate the effectiveness of such interventions.

Key points

  • As imagery is an individual intervention, an examination of individual perceptions of collective efficacy was most appropriate.
  • Elite athletes who use more MG-M imagery also have higher individual perceptions of collective efficacy.
  • For non-elite athletes, none of the imagery functions tested predicted individual perceptions of collective efficacy.
  • Performance accomplishments provided by MG-M imagery may increase individual perceptions of collective efficacy.
  • Future research should investigate further the effects of imagery intervention programmes on collective efficacy beliefs.
Key words: Mental rehearsal, mental skills, team confidence, self efficacy, group dynamics  相似文献   
46.
OBJECTIVES: To describe the results and complications of in situ preservation (ISP) of kidneys from donors after cardiac death (DCD). BACKGROUND: DCD donors are increasingly being used to expand the pool of donor kidneys. ISP reduces warm ischemic injury which is associated with DCD donation. METHODS: Insertion of a double-balloon triple-lumen catheter allows selective perfusion of the abdominal aorta to preserve the kidneys in situ. From January 2001 until August 2005, 133 ISP procedures were initiated in our procurement area. RESULTS: Fifty-six (42%) ISP procedures led to transplantation; in the remaining 77 cases (58%), the donation procedure was abandoned or both kidneys were discarded because of ISP complications (n = 31), poor graft quality (n = 23), no consent for donation (n = 13), medical contraindications (n = 8), or unknown cause (n = 2). Increasing donor age (odds ratio (OR) 1.06 per year, P < 0.001) and uncontrolled DCD donation (OR 5.4, P < 0.001) were independently correlated with ISP complications. After transplantation, prolonged double-balloon triple-lumen catheter insertion time was an independent predictor of graft failure (OR 2.0, P = 0.05). Selected controlled DCD donors were managed by rapid laparotomy and direct aortic cannulation; graft survival of these kidneys was superior to kidneys from controlled DCD donors managed by ISP. CONCLUSIONS: A minority of initiated ISP procedures led to transplantation, resulting in a high workload compared with donation after brain death. The association between increasing catheter insertion time and inferior graft outcome emphasizes the need for fast and effective surgery. Therefore, rapid laparotomy with direct aortic cannulation is preferred over ISP in controlled DCD donation. Despite these limitations, we have expanded our donor pool 3- to 4-fold by procuring DCD kidneys that were preserved in situ.  相似文献   
47.

Purpose

Plaster casts can cause burns. Synthetic casts do not. Composite plaster–synthetic casts have not been thoroughly evaluated. This study analyzed the temperature from plaster casts compared with composite casts in a variety of in vitro conditions that would simulate clinical practice.

Methods

A Pyrex cylinder filled with constant body temperature circulating water simulated a human extremity. Circumferential casts, of either plaster or composite construction (plaster inner layer with outer synthetic layer), were applied to the model. Peak temperatures generated by the exothermic reactions were studied relative to the following variables: dip water temperature (24 °C versus 40 °C), cast thickness (16, 30, and 34 ply), and delayed (5-min) versus immediate application of the synthetic outer layers. Peak temperatures from the all-plaster casts were compared with the composite casts of the same thickness. Finally, the relative cast strength was determined.

Results

Potentially dangerous high temperatures were measured only when 40 °C dip water was used or when thick (30- or 34-ply) casts were made. Cast strength increased with increasing cast thickness. However, the presence of synthetics in the composite casts layers did not increase cast strength in every case.

Conclusion

When applying composite casts, the outer synthetic layers should be applied several minutes after the plaster to minimize temperature rise. Composite casts do not routinely generate peak temperatures higher than plaster casts of similar thickness. Because the skin of children and the elderly is more temperature-sensitive than average adult skin, extra care should be taken to limit the exothermic reaction when casting children and the elderly: clean, room temperature dip water, minimal required cast thickness, avoidance of insulating pillows/blankets while the cast is drying.  相似文献   
48.

Background

After surgery for Hirschsprung's disease (HD) the majority of patients have satisfactory clinical outcomes. Nevertheless, a substantial number of patients remain who suffer from severe persistent constipation. Current consensus attributes these complaints to the hallmarks of HD. In non-HD patients a cause for severe constipation is dyssynergic defecation.

Methods

Retrospectively, we reviewed the medical records of ten postoperative HD patients with severe persistent constipation who had undergone extensive anorectal function tests to diagnose the reason for the constipation. We analyzed the results of these tests.

Results

During the last three years, ten postoperative HD patients with severe persistent constipation were given extensive anorectal function tests. All ten patients were diagnosed with dyssynergic defecation. The ages at the time of diagnosis ranged from 7 to 19 years with a median age of 12 years. Signs of an enlarged rectum were seen in all ten patients, with a maximum measured value of 845 mL.

Conclusions

Patients with HD may also suffer from dyssynergic defecation. It is important to consider this possibility when dealing with severe persistent constipation in postoperative HD patients. Viable options for treating dyssynergic defecation are available that could prevent irreversible long-term complications.  相似文献   
49.
Fifty-five patients with a clonal expansion of B lymphocytes in the peripheral blood were studied. According to the Kiel classification, 22 patients had chronic lymphocytic leukemia (CLL), 29 had immunocytoma (IC), two had prolymphocytic leukemia, and one had centrocytic lymphoma; one was not subclassified. Cytogenetic studies after B cell mitogen stimulation showed that six patients had an extra chromosome 12 as the sole abnormality. Another ten patients had an extra chromosome 12 together with other abnormalities. One patient had dup(12). Fifteen patients showed clonal aberrations without +12. Eleven patients showed only normal metaphases, and 12 patients were not evaluated cytogenetically. The cytogenetic subgroup pattern did not distinguish between CLL and IC patients. There was no significant difference between the CLL and IC groups as regards clinical findings and prognosis. However, the cytogenetic typing proved to be of prognostic significance. Increasing numbers of chromosomal aberrations within the cell clone were significantly associated with a poorer prognosis, ie, with impairment of survival (P = .04) and therapy-free survival (P less than 10(-4]. Patients with complex karyotypes (at least clonal aberrations) showed the poorest survival (P = .007). Patients with +12 required treatment earlier than patients with a normal karyotype (P = .01) and patients with karyotypic changes other than +12 (P = .006). These latter differences were even more pronounced when only IC patients were considered (P = .005 and P = .002, respectively). A multivariate analysis revealed that +12 was as strong an indicator of poor survival as advanced Rai or Binet stages and a stronger predictor of therapy-demanding disease.  相似文献   
50.
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