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81.
AIMS: Stenting has become an established interventional cardiology procedure for congenital heart disease. Although most stent procedures are completed successfully, complications may occur. This multicentre study evaluated early complications after stenting in patients with congenital heart disease, including potential risk factors. METHODS AND RESULTS: In this combined Dutch-Belgian retrospective study, 309 consecutive patients had undergone 366 catheterizations and received 464 stents in 13 different anatomical positions (418 sites). Seventy-two stenting-related complications (19%) occurred, of which 24 (5.7%) were major. Seven procedure-related deaths were documented (2.3%). Stent malpositioning and embolization were most common (7.7%). The use of non-premounted stents tended to be associated with higher complication rates. Centre inexperience with stenting and stenting of native vs. post-surgical stenosis tended to be associated with increased major complication rates. CONCLUSION: After stenting, complications are common for congenital heart disease. The vast diversity of stenotic sites combined with relatively small patient populations makes these procedures sensitive to complications. Combining operator experience may reduce the risks of stenting in congenital heart disease. The availability of premounted stents for greater vessel diameters will likely reduce incidences of stent migration and embolization.  相似文献   
82.
Serial transplantation and competitive repopulation were used to evaluate any loss of self-replicative capacity of bone marrow stem cells in a mouse model with increased and persistent hemopoietic demands. Congenic marrows from old control and from young and old mice with hereditary spherocytic anemia (sphha/sphha) were serially transplanted at 35-day intervals into normal irradiated recipients. Old anemic marrow failed or reverted to recipient karyotype at a mean of 3.5 transplants, and young anemic marrow reverted at a mean of 4.0 transplants, whereas controls did so at a mean of 5.0 transplants. In a competitive assay in which a mixture of anemic and control marrow was transplanted, the anemic marrow persisted to 10 months following transplantation; anemic marrow repopulation was greater if anemic marrow sex matched with the host. It is possible that lifelong stress of severe anemia decreases stem cell reserve in the anemic sphha/sphha mouse marrow. However, marginal differences in serial transplantation number and the maintenance of anemic marrow in a competition assay would suggest that marrow stem cells, under prolonged stress, are capable of exhibiting good repopulating and self-replicating abilities.  相似文献   
83.
The traumatic dural sinus injury — a clinical study   总被引:5,自引:0,他引:5  
Summary In a period of 13 years 978 cases of severe head injuries were operated on in our clinic. An analysis of the medical reports includes injuries of the superficial dural sinus (39 cases=4%): among these injuries of the anterior and central part of the superior sagittal sinus (66 per cent), injuries of the transverse sinus (18 per cent), injuries of the posterior part of the superior sagittal sinus (8 per cent), and combined injuries of different dural sinuses (8 per cent).Clinical data, i.e. the causes of accident, radiological examination results, intracranial lesions, operation technqiues and outcome are analysed and discussed. The analysis of cases with dural sinus injuries shows a high mortality rate (total mortality rate: 16 patients=41%; intra-operative mortality rate: 8 patients=20%).  相似文献   
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85.
OBJECTIVE: To investigate whether pathological changes in the umbilical artery (UA), ductus venosus (DV) and short-term fetal heart variation are related to perinatal outcome in severe, early intrauterine growth restriction (IUGR). METHODS: This multicenter, prospective, longitudinal, observational study was carried out in the Departments of Fetal Medicine and Obstetrics in Hamburg, Amsterdam, Utrecht and London. In 70 singleton pregnancies with IUGR fetuses, delivered at 26-33 weeks of gestation because of antepartum fetal distress, short-term variation (STV) of fetal heart rate, pulsatility index of the fetal UA (UA PI) and DV pulsatility index for veins (DV PIV) were assessed at least weekly. The final measurement was performed within 24 h of delivery. Standard cut-off levels (2 SD or 3 SD, absent flow or reversed flow) were used and new cut-off levels were calculated by means of receiver-operating characteristics analysis. Adverse outcome was defined as perinatal death, cerebral hemorrhage (> or = Grade II) or bronchopulmonary dysplasia before discharge. The predictive value for adverse outcome was calculated for different cut-off levels of the monitoring parameters, adjusted for gestational age (GA), by multivariate logistic regression analysis. Data were analyzed separately for three different time blocks, namely 8-14, 2-7 and 0-1 days before delivery. RESULTS: Adverse perinatal outcome occurred in 18/70 (26%) infants. During the last 24 h before delivery DV PIV and UA PI were significantly higher and STV lower in the adverse outcome group, while 2-7 days before delivery only DV PIV was significantly higher. Adverse perinatal outcome could be predicted at 0-1 days before delivery by DV PIV at a cut-off of three multiples of the SD (odds ratio (OR) 11.3; 95% CI 2.3-57) and GA (OR 0.4; 95% CI 0.3-0.8), at 2-7 days by DV PIV at 2 SD (OR 3.0; 95% CI 0.8-12) and GA (OR 0.5; 95% CI 0.3-0.8) and at 8-14 days by DV PIV at 2 SD (OR 3.9; 95% CI 0.8-20) and GA (OR 0.5; 95% CI 0.3-0.8). Other parameters did not contribute to the multivariate model. CONCLUSIONS: DV PIV measurement is the best predictor of perinatal outcome. This measurement may be useful in timing the delivery of early IUGR fetuses and in improving perinatal outcome, even when delivery may be indicated at an earlier GA. However, as GA was also an important factor influencing outcome, with poorer outcome at earlier gestation at delivery, this hypothesis needs to be tested in a multicenter, prospective, randomized trial.  相似文献   
86.
In 2002, the orthodontic clinic at Case Western Reserve University totally converted to digital photography. We want to share the learning curve during this transition with clinicians planning the same change. A system and a protocol were developed for this transition; they have been in use for over a year. This system allows the handling of digital cameras when there are more clinicians than cameras; it can be applied to various specialties or fields.  相似文献   
87.
88.
Zusammenfassung Es wird gezeigt, daß das Nichteintreten der Totenstarre in einer Gasatmosphäre bei bis zur Erschöpfung gereizten Froschmuskeln in hohem Maße abhängig ist von genügender Sauerstoffzufuhr zu allen Teilen.Beim dünnen M. sartorius genügt der Sauerstoff der Luft. Beim M. gastrocnemius ist es auch durch Sauerstoffüberdruck nicht möglich, den Eintritt der Starre nach Reizung zu verhindern. Erst durch gleichzeitiges Eintauchenlassen in Flüssigkeit wird dieser Zweck erfüllt.Bei Aufbewahrung inFlüssigkeit genügt für den M. sartorius im allgemeinen die Unterbringung in selbst O2-armer (ausgekochter) Ringerlösung zur Verhütung von Starre nach erschöpfender Reizung. Nachträgliches Durchleiten von Wasserstoff oder Stickstoff ruft Contractur hervor. Bei M. gastrocnemius genügt einfaches Unterbringen in Lösung nicht, erst bei Sauerstoffdurchleitung oder bei gleichzeitigem Sauerstoffüberdruck läßt sich Starre vermeiden.Durchleiten eines indifferenten Gasesvor Beginn der Reizung führt zu einer sehr raschen Erschöpfbarkeit des Muskels ohne Starre.Auch beimWarmblütermuskel gelingt es in vielen Fällen trotz erschöpfender Reizung den Starreeintritt zu verhindern, jedoch nur bei dünnen, ungeschädigten Muskeln, unter Sauerstoffüberdruck und in einem flüssigen Medium.Die Untersuchungen bestätigen durchaus die Auffassung, daß die Totenstarre eine Folge der Anhäufung von Milchsäure ist. Die Wegschaffung der letzteren durch Diffusion und Oxydation verhindert den Starreeintritt.Zum Schlusse möchte ich Herrrn ProfessorWinterstein auch an dieser Stelle meinen herzlichsten Dank aussprechen für die dauernde Unterstützung und Förderung bei vorliegender Arbeit.  相似文献   
89.
Fractures of the clival complex were diagnosed in a series of 17 patients admitted to the Maryland Institute for Emergency Medical Services System and the University of Maryland Medical System over a 30-month period. These fractures were divided pathologically into three types based upon their appearance on computed tomography: longitudinal, transverse, and oblique. The mechanisms of injury were similar in all groups, and the Glasgow Coma Scale scores at admission were comparable, regardless of fracture type, in survivors and nonsurvivors. Longitudinal fractures were associated with severe injury to the central nervous system and with brain stem infarction, and 4 of 6 (67%) of these patients died. Transverse fractures of the clival complex were found in 6 patients, 3 of whom (50%) died. All of these patients had fractures of the petrous ridge; 2 of the 3 survivors had multiple cranial nerve deficits, and one patient developed a carotid-cavernous fistula. Of the 5 patients with oblique clival fractures, 2 survived (40%), both of whom had multiple cranial nerve palsies; in addition, one of these patients developed a carotid-cavernous fistula. Using the present generation of computed tomographic scanners, fractures of the clival complex can be reliably diagnosed; they are probably more common than previously believed and can be separated into three groups based on the characteristics on computed tomographic scans and clinical findings.  相似文献   
90.
Between 1974 and 1984, 173 patients were treated for squamous cell carcinoma of the tongue base. Fifty-four patients had T1 or T2 primaries, while 115 patients had T3 or T4 tumors (4 were not staged). Lymph node metastasis was present in 120 patients. Early primary tumors treated with surgery or radiotherapy had a control rate of 83% (5 of 6 tumors) and 89% (40 of 45 tumors), respectively. For advanced primary tumors, definitive radiotherapy produced a local control rate of 55% (42 of 76 tumors), compared with 79% (23 of 29 tumors) for surgery and postoperative radiotherapy. If primary control was obtained, the regional failure rate was less than 10%. Tumor growth patterns were predictive of the response to radiotherapy. The primary control rate at 2 years for 21 patients with exophytic tumors was 84% as opposed to 58% for 62 patients with ulcerative-infiltrative tumors (p = 0.04). Radiotherapy is effective for early stage or exophytic tumors, whereas for advanced or deeply invasive tumors combined therapy enhances local control.  相似文献   
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