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51.
The objective of this study was to analyze the long-term morbidity and mortality in patients with a clinically diagnosed vertebral fracture. Seventy men with a mean age of 70 years (range 50–91 years) and 187 women with a mean age of 72 years (range 50–96 years) were radiographically diagnosed as having a vertebral fracture in the thoracic or lumbar spine at the Malmö University Hospital (Sweden) during 1979. At the time of a follow-up examination 12 years later, 56 of the 76 patients who were still alive participated in an investigation that evaluated back pain and subjective health status by a questionnaire. Forty-four of these subjects also participated in a further radiologic examination of the spine. Serving as controls were age- and gender-matched subjects from the Malmö cohort of the European Vertebral Osteoporosis Study (EVOS). A mortality analysis was also conducted, covering 22 years following the baseline fracture. There were more female patients, who, in comparison with the controls, 12 years after the diagnosis, had had back pain during the year preceding the follow-up (72% vs 33%, P < 0.001), had current back pain (42% vs. 19%, P = 0.006), and had a subjectively impaired health status (44% vs. 17%, P < 0.001). The corresponding differences in men reached only a borderline significance, for both back pain during the year preceding the follow-up (60% vs. 28%, P = 0.07) and current back pain (40% vs. 15%, P = 0.09), whereas there was no difference in subjective health status. The incidence of new vertebral fractures in individuals with a clinically diagnosed vertebral fracture during the following 12 years was in men 25 per 1,000 person-years and in women 49 per 1000 person-years. There were more women with a new vertebral fracture at the 12-year follow-up examination who, in comparison with women without a new fracture, had had back pain during the year preceding the follow-up examination (90% vs. 50%, age-adjusted P = 0.02) and had current back pain (65% vs. 21%, age-adjusted P = 0.03). Women with a new vertebral fracture at the 12-year follow-up examination had a higher subsequent mortality rate in the next 10 years [age-adjusted hazard ratio 2.8 (95% CI 1.0–7.9)] as compared with women without. The mortality rate during the 22 years following the diagnosis among the male patients was 111.7 per 1,000 person-years as compared with 73.4 per 1,000 person-years among the male population at risk. The mortality rate among the female patients was 95.1 per 1,000 person-years as compared with 62.0 per 1,000 person-years among the female population at risk. We conclude that a clinically diagnosed thoracic or lumbar vertebral fracture in the elderly can be regarded as a risk factor for subsequent, long-term morbidity, especially in women, and for mortality in both genders.  相似文献   
52.
53.

Purpose

In August 2011, orthopaedic surgeons from more than 20 countries attended a summit on anatomic anterior cruciate ligament (ACL) reconstruction. The summit offered a unique opportunity to discuss current concepts, approaches, and techniques in the field of ACL reconstruction among leading surgeons in the field.

Methods

Five panels (with 36 panellists) were conducted on key issues in ACL surgery: anatomic ACL reconstruction, rehabilitation and return to activity following anatomic ACL reconstruction, failure after ACL reconstruction, revision anatomic ACL reconstruction, and partial ACL injuries and ACL augmentation. Panellists’ responses were secondarily collected using an online survey.

Results

Thirty-six panellists (35 surgeons and 1 physical therapist) sat on at least one panel. Of the 35 surgeons surveyed, 22 reported performing “anatomic” ACL reconstructions. The preferred graft choice was hamstring tendon autograft (53.1 %) followed by bone-patellar tendon-bone autograft (22.8 %), allograft (13.5 %), and quadriceps tendon autograft (10.6 %). Patients generally returned to play after an average of 6 months, with return to full competition after an average of 8 months. ACL reconstruction “failure” was defined by 12 surgeons as instability and pathological laxity on examination, a need for revision, and/or evidence of tear on magnetic resonance imaging. The average percentage of patients meeting the criteria for “failure” was 8.2 %.

Conclusions

These data summarize the results of five panels on anatomic ACL reconstruction. The most popular graft choice among surgeons for primary ACL reconstructions is hamstring tendon autograft, with allograft being used most frequently employed in revision cases. Nearly half of the surgeons surveyed performed both single- and double-bundle ACL reconstructions depending on certain criteria. Regardless of the technique regularly employed, there was unanimous support among surgeons for the use of “anatomic” reconstructions using bony and soft tissue remnant landmarks.

Level of evidence

V.  相似文献   
54.
Mechanical efficiency of positive work in running at different speeds   总被引:2,自引:0,他引:2  
To investigate the possible role of elastic potentiation on mechanical efficiency, three male marathon runners were filmed while running on a treadmill at various steady-state speeds ranging from 7.0-22.0 km X h-1. Kinematic and mechanical energy analyses were performed from the film. Expired air was collected for energy expenditure determination. The analysis disclosed that during contact on the treadmill the knee and ankle joints initially had a phase of negative (flexion) angular velocity, followed by a positive velocity. In the hip joint the stretch-shortening cycle of the extensor muscles occurred primarily during the flight phase. The mean vertical and horizontal forces of the negative and positive phases of the contact period increased linearly with the increase in the running speed. The calculated mechanical efficiency of positive work was high but relatively constant (55.1 +/- 12.7%) across all speeds. The absolute contribution of the extra work, which comes from the stored elastic energy to the positive work, increased with running speed; however, its relative value (0.61 +/- 0.09 J X min-1 X kg-1) remained constant at all measured speeds. It is suggested, therefore, that when the flight phase is included in the mechanical energy calculations, the measured efficiency for the positive work reaches a high but constant value in running at low-to-moderate speeds.  相似文献   
55.

Purpose

Tendons generally exhibit poor healing capacity, probably due to slow cell regeneration potential and low vascularization. The potential to regenerate may partly be due to activation of stem/progenitor cells localized in the tendon or its vicinity. In the present study, we attempted to determine where in the rat Achilles tendon stem/progenitor cells reside and to investigate the effect of exercise on cell proliferation in the in vivo situation.

Method

We used bromodeoxyuridine (BrdU) labelling to investigate proliferation and label-retaining cells (i.e. slow-cycling cells) in non-exercised and exercised rats, in combination with immunostaining of the stem cell marker nucleostemin. Rat Achilles tendons were harvested 14, 28, 56 and 105 days after BrdU administration.

Results

We found the proportion of stem/progenitor cells to be twice as high in the distal tendon (DT) compared with the mid/proximal tendon (MPT) and that paratenon/endotenon regions appear to host a pool of existing stem/progenitor cells. Exercise increased the BrdU-stained cell population after 14 days only (DT region p = 0.032, MPT p = 0.065), indicating effect mainly on more differentiated cells, since the nucleostemin-positive cells (i.e. stem/progenitor cells) remained unaffected in the intact Achilles tendon.

Conclusion

Stem/progenitor cells exist in several areas of the rat Achilles tendon which implies a possible stem cell regeneration pool of different origins. The distal region has twice the amount of stem/progenitor cells compared with the mid/proximal region, indicating a potentially higher stem cell activity in this tissue. Daily moderate exercise (treadmill running) mainly improves in vivo cell proliferation in rapidly proliferating cells, whereas the stem/progenitor pool remains constant.  相似文献   
56.
The aim of this study was to evaluate whether a prevalent vertebral deformity predicts mortality and fractures in both men and women. In the city of Malmö, 598 individuals (298 men, 300 women; age 50–80 years) were selected from the city's population and were included in the Swedish part of the European Vertebral Osteoporosis Study (EVOS). At baseline the participants answered a questionnaire and lateral spine radiographs were performed. The prevalence of subjects with vertebral deformity was assessed using a morphometric method. The mortality during a 10-year follow-up period was determined through the register of the National Swedish Board of Health and Welfare. Eighty-five men and 43 women died during the study period. The subsequent fracture incidence during the follow-up period was ascertained by postal questionnaires, telephone interviews and by a survey of the archives of the Department of Radiology in the city hospital. Thirty-seven men and 69 women sustained a fracture during the study period. Data are presented as hazard ratios (HR) with 95% confidence interval (95% CI) within brackets. Prevalent vertebral deformity, defined as a reduction by more than 3 standard deviations (SD) in vertebral height ratio, predicted mortality during the forthcoming decade in both men [age-adjusted HR 2.4 (95% CI 1.6–3.9)] and women [age-adjusted HR 2.3 (95% CI 1.3–4.3)]. In men there was an increased mortality due to cardiovascular and pulmonary diseases and in women due to cancer. Prevalent vertebral deformity predicted an increased risk of any fracture during the forthcoming decade in both men [age-adjusted HR 2.7 (95% CI 1.4–5.3)] and women [age-adjusted HR 1.8 (95% CI 1.1–2.9)]. Prevalent vertebral deformity predicted an increased risk of any subsequent fragility fracture in women [age-adjusted HR 2.0 (95% CI 1.1–3.5)]; however, in men the increased risk was nonsignificant [age-adjusted HR 1.9 (95% CI 0.7–5.1)]. In summary, a prevalent vertebral deformity can predict both increased mortality and increased fracture incidence during the following decade in both men and women. We conclude that prevalent vertebral deformity could be used as a risk factor in both genders for mortality and future fracture.  相似文献   
57.
The aim of this study was to evaluate the effect of increasing the amount of time spent in physical education classes on bone mineral accrual and gain in bone size in prepubertal Danish children. A total of 135 boys and 108 girls, aged 6–8 years, were included in a school-based curriculum intervention program where the usual time spent in physical education classes was doubled to four classes (180 min) per week. The control group comprised age-matched children (62 boys and 76 girls) recruited from a separate community who completed the usual Danish school curriculum of physical activity (90 min/week). Dual-energy X-ray absorptiometry was used to evaluate bone mineral content (BMC; g), bone mineral density (g/cm2), and bone width at the calcaneus and distal forearm before and after 3 years of intervention. Anthropometrics and Tanner stages were evaluated on the same occasions. General physical activity was measured with an accelerometer worn for 4 days. In girls, the intervention group had a 12.5% increase (P = 0.04) in distal forearm BMC and a 13.2% increase (P = 0.005) in distal forearm scanned area compared with girls in the control group. No differences were found between the intervention and control groups in boys. Increasing the frequency of physical education classes for prepubertal children is associated with a higher accrual of bone mineral and higher gain in bone size after 3 years in girls but not in boys.  相似文献   
58.
BACKGROUND CONTEXT: Several studies report a favorable short-term outcome after nonoperatively treated two-column thoracic or lumbar burst fractures in patients without neurological deficits. Few reports have described the long-term clinical and radiological outcome after these fractures, and none have, to our knowledge, specifically evaluated the long-term outcome of the discs adjacent to the fractured vertebra, often damaged at injury and possibly at an increased risk of height reduction and degeneration with subsequent chronic back pain. PURPOSE: To evaluate the long-term clinical and radiological outcome after nonoperatively treated thoracic or lumbar burst fractures in adults, with special attention to posttraumatic radiological disc height reduction. STUDY DESIGN: Case series. PATIENT SAMPLE: Sixteen men with a mean age of 31 years (range, 19-44) and 11 women with a mean age of 40 years (range, 23-61) had sustained a thoracic or lumbar burst fracture during the years 1965 to 1973. Four had sustained a burst fracture Denis type A, 18 a Denis type B, 1 a Denis type C, and 4 a Denis type E. Seven of these patients had neurological deficits at injury, all retrospectively classified as Frankel D. OUTCOME MEASURES: The clinical outcome was evaluated subjectively with Oswestry score and questions regarding work capacity and objectively with the Frankel scale. The radiological outcome was evaluated with measurements of local kyphosis over the fractured segment, ratios of anterior and posterior vertebral body heights, adjacent disc heights, pedicle widths, sagittal width of the spinal canal, and lateral and anteroposterior displacement. METHODS: From the radiographical archives of an emergency hospital, all patients with a nonoperatively treated thoracic or lumbar burst fracture during the years 1965 to 1973 were registered. The fracture type, localization, primary treatment, and outcome were evaluated from the old radiographs, referrals, and reports. Twenty-seven individuals were clinically and radiologically evaluated a mean of 27 years (range, 23-41) after the injury. RESULTS: At follow-up, 21 former patients reported no or minimal back pain or disability (Oswestry Score mean 4; range, 0-16), whereas 6 former patients (of whom 3 were classified as Frankel D at baseline) reported moderate or severe disability (Oswestry Score mean 39; range, 26-54). Six former patients were classified as Frankel D, and the rest as Frankel E. Local kyphosis had increased by a mean of 3 degrees (p<.05), whereas the discs adjacent to the fractured vertebrae remained unchanged in height during the follow-up. CONCLUSIONS: Nonoperatively treated burst fractures of the thoracic or lumbar spine in adults with or without minor neurological deficits have a predominantly favorable long-term outcome, and there seems to be no increased risk for subsequent disc height reduction in the adjacent discs.  相似文献   
59.
BACKGROUND: Six men and seven women, aged 62 years, bedridden due to back pain from a septic spondylitis in the thoracolumbar region and not responding to conservative treatment, were operated on with transpedicular stabilisation of the affected segments to enhance mobilisation. All patients experienced immediately reduced back pain, allowing them to leave their bed and start mobilisation during the first postoperative day. At follow-up after a mean of 29 months (range 13-60 months) only one was using analgesics. RESULTS: Nine of the 11 patients with pathological neurology at surgery had improved, none had deteriorated, and all were ambulatory without bladder or bowel disturbances. Seven had achieved a solid interbody fusion, with a continued radiographic decrease in the spondylitic change in the rest, indicating that a progressive interbody fusion was in progress. Three individuals had increased kyphosis, a mean of 11 deg compared with the postoperative radiographs.  相似文献   
60.
This 2-year prospective controlled exercise intervention trial in 99 girls at Tanner stage 1, evaluating a school curriculum-based training program on a population-based level, showed that the annual gain in BMC, aBMD, and bone size was greater in the intervention group than in the controls. INTRODUCTION: Most exercise intervention studies in children, evaluating the accrual of BMD, include volunteers and use specifically designed osteogenic exercise programs. The aim of this study was to evaluate a 2-year general school-based exercise intervention program in a population-based cohort of girls at Tanner stage 1. MATERIALS AND METHODS: Forty-nine girls 7-9 years of age in grades 1 and 2 in one school were included in a school curriculum-based exercise intervention program of general physical activity for 40 minutes per school day (200 minutes/week). Fifty healthy age-matched girls in three neighboring schools, assigned to the general Swedish school curriculum of physical activity (60 minutes/week), served as controls. All girls were premenarchal, remaining in Tanner stage 1 during the study. BMC (g) and areal BMD (aBMD; g/cm2) were measured with DXA of the total body (TB), the lumbar spine (L2-L4 vertebrae), the third lumbar vertebra (L3), the femoral neck (FN), and the leg. Volumetric BMD (vBMD; g/cm3) and bone size were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. Height and weight were also registered. Baseline measurements were performed before the intervention was initiated. Follow-up was done after 2 years. RESULTS: No differences between the groups were found at baseline in age, anthropometrics, or bone parameters. The annual gain in BMC was greater in the intervention group than in the controls: L2-L4, mean 3.8 percentage points (p = 0.007); L3 vertebra, mean 7.2 percentage points (p < 0.001); legs, mean 3.0 percentage points (p = 0.07). The intervention group had a greater annual gain in aBMD: total body, mean 0.6 percentage points (p = 0.006), L2-L4, mean 1.2 percentage points (p = 0.02), L3 vertebra, mean 1.6 percentage points (p = 0.006); legs, mean 1.2 percentage points (p = 0.007). There was also a greater mean annual gain in bone size in the L3 vertebra (mean 1.8 percentage points; p < 0.001) and in the FN (mean 0.3 percentage points; p = 0.02). CONCLUSIONS: A general school-based exercise program for 2 years for 7- to 9-year-old girls (baseline) enhances the accrual of BMC and BMD and increases bone size.  相似文献   
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