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1.
BACKGROUND: Laparoscopic surgery for gastric cancer is technically feasible, but it is not widely accepted because it has not been evaluated from the standpoint of oncologic outcome. We conducted a retrospective, multicenter study of a large series of patients in Japan to evaluate the short- and long-term outcomes of laparoscopic gastrectomy for early gastric cancer (EGC). METHODS: The study group comprised 1294 patients who underwent laparoscopic gastrectomy during the period April 1994 through December 2003 in 16 participating surgical units (Japanese Laparoscopic Surgery Study Group). The short- and long-term outcomes of these patients were examined. RESULTS: Distal gastrectomy was performed in 1185 patients (91.5%), proximal gastrectomy in 54 (4.2%), and total gastrectomy in 55 (4.3%); all were performed laparoscopically. The morbidity and mortality rates associated with these operations were 14.8% and 0%, respectively. Histologically, 1212 patients (93.7%) had stage IA disease, 75 (5.8%) had stage IB disease, and 7 (0.5%) had stage II disease (the UICC staging). Cancer recurred in only 6 (0.6%) of 1294 patients treated curatively (median follow-up, 36 months; range, 13-113 months). The 5-year disease-free survival rate was 99.8% for stage IA disease, 98.7% for stage IB disease, and 85.7% for stage II disease. CONCLUSIONS: Although our findings may be considered preliminary, our data indicate that laparoscopic surgery for EGC yields good short- and long-term oncologic outcomes.  相似文献
2.
Body mass index as a predictor of fracture risk: A meta-analysis   总被引:15,自引:15,他引:11  
Low body mass index (BMI) is a well-documented risk factor for future fracture. The aim of this study was to quantify this effect and to explore the association of BMI with fracture risk in relation to age, gender and bone mineral density (BMD) from an international perspective using worldwide data. We studied individual participant data from almost 60,000 men and women from 12 prospective population-based cohorts comprising Rotterdam, EVOS/EPOS, CaMos, Rochester, Sheffield, Dubbo, EPIDOS, OFELY, Kuopio, Hiroshima, and two cohorts from Gothenburg, with a total follow-up of over 250,000 person years. The effects of BMI, BMD, age and gender on the risk of any fracture, any osteoporotic fracture, and hip fracture alone was examined using a Poisson regression model in each cohort separately. The results of the different studies were then merged. Without information on BMD, the age-adjusted risk for any type of fracture increased significantly with lower BMI. Overall, the risk ratio (RR) per unit higher BMI was 0.98 (95% confidence interval [CI], 0.97–0.99) for any fracture, 0.97 (95% CI, 0.96–0.98) for osteoporotic fracture and 0.93 (95% CI, 0.91–0.94) for hip fracture (all p <0.001). The RR per unit change in BMI was very similar in men and women ( p >0.30). After adjusting for BMD, these RR became 1 for any fracture or osteoporotic fracture and 0.98 for hip fracture (significant in women). The gradient of fracture risk without adjustment for BMD was not linearly distributed across values for BMI. Instead, the contribution to fracture risk was much more marked at low values of BMI than at values above the median. This nonlinear relation of risk with BMI was most evident for hip fracture risk. When compared with a BMI of 25 kg/m2, a BMI of 20 kg/m2 was associated with a nearly twofold increase in risk ratio (RR=1.95; 95% CI, 1.71–2.22) for hip fracture. In contrast, a BMI of 30 kg/m2, when compared with a BMI of 25 kg/m2, was associated with only a 17% reduction in hip fracture risk (RR=0.83; 95% CI, 0.69–0.99). We conclude that low BMI confers a risk of substantial importance for all fractures that is largely independent of age and sex, but dependent on BMD. The significance of BMI as a risk factor varies according to the level of BMI. Its validation on an international basis permits the use of this risk factor in case-finding strategies.  相似文献
3.
Estimates of optimal vitamin D status   总被引:13,自引:13,他引:9  
Vitamin D has captured attention as an important determinant of bone health, but there is no common definition of optimal vitamin D status. Herein, we address the question: What is the optimal circulating level of 25-hydroxyvitamin D [25(OH)D] for the skeleton? The opinions of the authors on the minimum level of serum 25(OH)D that is optimal for fracture prevention varied between 50 and 80 nmol/l. However, for five of the six authors, the minimum desirable 25(OH)D concentration clusters between 70 and 80 nmol/l. The authors recognize that the average older man and woman will need intakes of at least 20 to 25 mcg (800 to 1,000 IU) per day of vitamin D3 to reach a serum 25(OH)D level of 75 nmol/l. Based on the available evidence, we believe that if older men and women maintain serum levels of 25(OH)D that are higher than the consensus median threshold of 75 nmol/l, they will be at lower risk of fracture.  相似文献
4.
5.
Burn reconstruction of forefoot remains as a difficult challenge, because the local flap alternatives are limited. We evaluated the efficiency of distally based medial plantar fasciocutaneous island flap in the coverage of forefoot defects resulting from release of toe contracture and burn debridement. Four patients with toe contractures and two patients with third degree burn in forefoot were treated between June 2004 and February 2006. The mean follow-up period was 10.4 months. The flaps were elevated as with a fasciocutaneous base on the distal medial plantar artery. The dimensions of the flaps ranged from 4cmx3cm to 5cmx4cm. The skin over the pedicle was included as a part of flap in three cases. Concomitant vein of the pedicle was anastomosed with the first plantar digital vein in four cases. In the early postoperative period, one flap used to cover third degree burn due to high-voltage electric injury was lost completely. We concluded that this flap was an appropriate alternative reconstructive option for the forefoot defect. Including skin and subcutaneous tissue over the pedicle to flap protects the pedicle against kinking and compression. Venous supercharging of the flap improves venous drainage.  相似文献
6.
BACKGROUND: Mesenchymal stem cells (MSCs) play a crucial role in hematopoietic development and have been shown to exert a powerful immunosuppressive effect. In this study, we investigated the effect of bone marrow MSC on the differentiation and function of peripheral blood monocytes into dendritic cells (DCs). METHODS: Human MSCs, generated from normal bone marrow, were added to peripheral blood monocytes stimulated in vitro with granulocyte-macrophage colony stimulating factor and interleukin-4 to become DCs. Monocytes were then examined for the expression of markers characteristic of DCs and their ability to stimulate allogeneic T cells. In addition, the effect of MSCs on the cell cycle of monocyte-derived DCs and the expression of various cell cycle proteins were analyzed by cytometric analysis and Western blotting with specific antibodies. RESULTS: MSCs blocked the differentiation of monocytes into DCs and impaired their antigen-presenting ability. This resulted from a block of monocytes from entering the G1 phase of the cell cycle with a progressive number of cells accumulating in the G0 phase. Cyclin D2 was downregulated. However, differently from what was observed in T-cells stimulated in the presence of MSCs, the expression of p27 was found decreased, suggesting the involvement of similar but not identical pathways. CONCLUSIONS: We conclude that MSCs impair monocyte differentiation and function by interfering with the cell cycle. These findings imply that MSC-induced immunosuppression might be a side product of a more general antiproliferative effect.  相似文献
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8.
OBJECTIVE: Due to limited resources, improvement of preservation solutions is still of great importance in cardiac transplant surgery. New additives with antioxidant properties were tested with respect to coronary function of isolated rat hearts. METHODS: Bretschneider HTK solution containing none or an antioxidant additive (deferoxamine, trolox or LK 616) was used for 8h cold cardioplegia. After reperfusion with Krebs-Henseleit buffer (KHB), we assessed vascular dilator capacity (bradykinin, adenosine triphosphate, reactive hyperemia), myocardial function (left ventricular developed pressure, heart rate, oxygen consumption) and release of biochemical markers (aspartate aminotransferase, creatine kinase, lactate dehydrogenase, troponin, adenosine). RESULTS: Bradykinin- and adenosine triphosphate-induced vasodilations were largely reduced in hearts stored 8h in traditional HTK as compared to unstored controls. Storage in HTK+LK 616 significantly improved bradykinin-induced vasodilation. Vasodilation toward ATP was best preserved in hearts stored in HTK+deferoxamine. Deferoxamine and trolox, both improved reactive hyperaemic response during reperfusion. Left ventricular pressure development was significantly reduced after 8h cardioplegia, but no difference existed between different cardioplegia groups. Release of biochemical markers of tissue injury was similar in all cardioplegia groups. After storage in HTK+LK 616 (100 microM), however, heart marker release was slightly augmented as compared to HTK. CONCLUSIONS: Despite similar myocardial function and marker release, coronary vascular function after cardioplegic storage may profit by addition of iron chelators (or antioxidants) to traditional HTK solution.  相似文献
9.
Fragility fractures are a strong indicator of underlying osteoporosis (OP). With the risk of future fracture being increased 1.5- to 9.5-fold following a fragility fracture, the diagnosis and treatment of OP in men and women with fragility fractures provides the opportunity to prevent future fragility fractures. This review describes the current status of practice in investigation and diagnosis of OP in men and women with fragility fractures, the rates and types of postfracture treatment in patients with fragility fractures and OP, interventions undertaken in this population, and the barriers to OP identification and treatment. A literature search performed in Medline, Healthstar, CINAHL, EMBASE, PreMedline, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews identified 37 studies on OP diagnosis, treatment, and interventions. The studies varied in design methodology, study facilities, types of fractures, and pharmacological treatments. Some studies revealed that no patients with fragility fractures received investigation or treatment for underlying OP. Investigation of OP by bone mineral density was low: 14 of 16 studies reported investigation of less than 32% of patients. Investigation by bone mineral density resulted in high rates of OP diagnosis (35–100%), but only moderate use of calcium and vitamin D (8–62%, median 18%) and bisphosphoates (0.5–38%) in patients investigated postfracture. Studies on barriers to OP identification and treatment focused on various groups of health practitioners. Barriers included the cost of therapies, time and cost of resources for diagnosis, concerns about medications, and the lack of clarity regarding the responsibility to undertake this care.  相似文献
10.
Background and Objective: As Light Emitting Diode (LED) devices are commercially introduced as an alternative for Low Level Laser (LLL) Therapy, the ability of LED in influencing wound healing processes at cellular level was examined. Study Design/Materials and Methods: Cultured fibroblasts were treated in a controlled, randomized manner, during three consecutive days, either with an infrared LLL or with a LED light source emitting several wavelengths (950 nm, 660 nm and 570 nm) and respective power outputs. Treatment duration varied in relation to varying surface energy densities (radiant exposures). Results: Statistical analysis revealed a higher rate of proliferation (p 0.001) in all irradiated cultures in comparison with the controls. Green light yielded a significantly higher number of cells, than red (p 0.001) and infrared LED light (p 0.001) and than the cultures irradiated with the LLL (p 0.001); the red probe provided a higher increase (p 0.001) than the infrared LED probe and than the LLL source. Conclusion: LED and LLL irradiation resulted in an increased fibroblast proliferation in vitro. This study therefore postulates possible stimulatory effects on wound healing in vivo at the applied dosimetric parameters.  相似文献
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