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81.
Zusammenfassung Infektionen mit Herpes-simplex-Virus Typ I und Typ II (HSV) und Varicella/Zoster-Viren (VZV) w?hren ein Leben lang. Klinische Manifestationen werden durch den Lebenszyklus der Viren – Prim?rinfektion-Latenzphase-endogene Reaktivierung – bestimmt. Prim?rinfektionen mit HSV und VZV führen w?hrend der Schwangerschaft oft zu schwersten, auch t?dlichen Erkrankungen. Insbesondere in der ersten H?lfte der Schwangerschaft sind solche Infektionen mit einer Gefahr für den F?ten verbunden: als Folge einer f?talen Infektion kommt es zu einer erh?hten Rate von Spontanaborten, Totgeburten und von f?talen Mi?bildungen; das „f?tale Varizellensyndrom” stellt dabei eine gut definierte Entit?t dar. In der Peripartalphase stellen sowohl Varizellen aber auch ein Herpes genitalis (auch Rezidive) im Geburtskanal potentielle Infektionsquellen dar, welche zu lebensbedrohlichen Erkrankungen des Neugeborenen führen k?nnen. In dieser Arbeit werden die unterschiedlichen Phasen des Lebenszyklus von HSV/VZV dargestellt und die Besonderheiten dieser Infektionkrankheiten in der Schwangerschaft aufgezeigt. Besonders hervorgehoben wird Epidemiologie und klinisches Bild der Erkrankungen des F?ten und Neugeborenen, und schlie?lich werden deren Prophylaxe und Therapie besprochen. Eingegangen am 15. Dezember 1998 Angenommen am 3. Februar 1999  相似文献   
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OBJECTIVE: The surgical treatment of aortoesophageal fistulae (AEF) has a high morbidity and mortality rate. We report our experience with the sequential use of endovascular thoracic stentgrafts and cryopreserved aortic homografts for in situ repair of the descending thoracic aorta. METHODS: In a 7-year period, 6 patients with AEF were treated at our center. After primary endovascular repair in all cases, 4 patients subsequently underwent in situ repair of the descending thoracic aorta with cryopreserved homografts. Long-term antibiotic therapy was given in all cases. Recent clinical status and radiologic findings on follow-up studies of each patient were analyzed. The mean follow-up time was 35 months (range, 2-76). RESULTS: Endovascular stentgraft repair was technically successful in all cases. Two patients were not candidates for open surgical repair because of their medical condition; they both died within 8 weeks after discharge from the hospital, 1 from recurrent septic episodes, and the other from upper gastrointestinal bleeding. One of 4 patients who had undergone open surgical repair died 1 year later from upper gastrointestinal bleeding that occurred presumably due to an infectious degeneration of the homograft after secondary infection with a methacillin-resistant Staphyloccocus aureus. In 1 case persistent paraplegia and in another case persistent renal failure occurred. CONCLUSION: The use of cryopreserved homografts is a valuable alternative to in situ repair with prosthetic vascular grafts or extra-anatomic reconstructions in the surgical treatment of AEF. Endovascular stentgraft placement plays a role as a bridging procedure in emergency situations.  相似文献   
86.
The number of patients returning to dialysis after graft failure increases. Surprisingly, little is known about the clinical and immunological outcomes of this cohort. We retrospectively analyzed 254 patients after kidney allograft loss between 1997 and 2017 and report clinical outcomes such as mortality, relisting, retransplantations, transplant nephrectomies, and immunization status. Of the 254 patients, 49% had died 5 years after graft loss, while 27% were relisted, 14% were on dialysis and not relisted, and only 11% were retransplanted 5 years after graft loss. In the complete observational period, 111/254 (43.7%) patients were relisted. Of these, 72.1% of patients were under 55 years of age at time of graft loss and only 13.5% of patients were ≥65 years. Age at graft loss was associated with relisting in a logistic regression analysis. In the complete observational period, 42 patients (16.5%) were retransplanted. Only 4 of those (9.5%) were ≥65 years at time of graft loss. Nephrectomy had no impact on survival, relisting, or development of dnDSA. Patients after allograft loss have a high overall mortality. Immunization contributes to long waiting times. Only a very limited number of patients are retransplanted especially when ≥65 years at time of graft loss.  相似文献   
87.
The Centers for Medicare and Medicaid Services (CMS) designated the achieved urea reduction ratio (URR) as a pay-for-performance measure, but to what extent this measure reflects patient characteristics and adherence instead of its intent to reflect facility performance is unknown. Here, we quantified the contributions of patient case-mix and adherence to the variability in achieving URR targets across dialysis facilities. We found that 92% of 10,069 hemodialysis patients treated at 173 facilities during the last quarter of 2004 achieved the target URR ≥65%. Mixed-effect models with random intercept for dialysis facility revealed a significant facility effect: 11.5% of the variation in achievement of target URR was attributable to the facility level. Adjusting for patient case-mix reduced the proportion of variation attributable to the facility level to 6.7%. Patient gender, body surface area, dialysis access, and adherence with treatment strongly associated with achievement of the URR target. We could not identify specific facility characteristics that explained the remaining variation between facilities. These data suggest that if adherence is not a modifiable patient characteristic, providers could be unfairly penalized for caring for these patients under current CMS policy. These penalties may have unintended consequences.  相似文献   
88.

Objectives

Improved fixation techniques with optional use of bone cements for implant augmentation have been developed to enhance stability and reduce complication rates after osteosynthesis of femoral neck fractures. This biomechanical study aimed to evaluate the effect of cement augmentation on implant anchorage and overall performance of screw-anchor fixation systems in unstable femoral neck fractures.

Methods

Ten pairs of human cadaveric femora were used to create standardized femoral neck fractures (Pauwels type 3 fractures; AO/OTA 31-B2) with comminution and were fixed by means of a rotationally stable screw-anchor (RoSA) system. The specimens were assigned pairwise to two groups and either augmented with PMMA-based cement (Group 1, augmented) or left without such augmentation (Group 2, control).Biomechanical testing, simulating physiological loading at four distinct load levels, was performed over 10.000 cycles for each level with the use of a multidimensional force-transducer system. Data was analysed by means of motion tracking.

Results

Stiffness, femoral head rotation, implant migration, femoral neck shortening, and failure load did not differ significantly between the two groups (p?≥?.10). For both groups, the main failure type was dislocation in the frontal plane with consecutive varus collapse). In the cement-augmented specimens, implant migration and femoral neck shortening were significantly dependent on bone mineral density (BMD), with higher values in osteoporotic bones. There was a correlation between failure load and BMD in cement-augmented specimens.

Conclusion

In screw-anchor fixation of unstable femoral neck fractures, bone-cement augmentation seems to show no additional advantages in regard to stiffness, rotational stability, implant migration, resistance to fracture displacement, femoral neck shortening or failure load.  相似文献   
89.
The reporting quality of publications of clinical trials can affect the quality of clinical decision-making. We systematically assessed the quality of publications of large multicenter trials evaluating immunosuppressive regimens in de novo kidney transplantation. Study quality, reporting quality and accessibility of the results of 63 publications were assessed independently by three blinded investigators using an instrument combining the Jadad scale with a list of reporting quality items. Study quality was rated with an average of only 2.3 (range 1-5) on the Jadad scale. Unblinded studies were reported in 68.3% of publications and follow-up longer than 12 months was reported for only 13 out of 50 studies. The reviewed publications fulfilled an average of 69.1% of the reporting quality criteria. Fifty-four percent of publications did not report both treated and biopsy-proven rejections. Whether reported graft survival was censored for death could not be determined for 27% of publications. Only a few publications gave confidence intervals (CIs) or stated whether additional analyses were pre-specified. Even the largest trials of immunosuppression in kidney transplantation show considerable quality deficits in their design and publication. Additional efforts are required of investigators, editors and sponsors to achieve maximum study and reporting quality.  相似文献   
90.
OBJECTIVES: To develop a physiologic test of nasal responsiveness in mice and to evaluate whether mice with acute bacterial sinusitis develop nasal hyperresponsiveness. DESIGN: Several experimental studies will be described. The first was a titration pilot study. The second was a randomized, placebo-controlled study. The remainder were before-and-after trials. SPECIES: BALB/c or C57BL/6 mice. INTERVENTIONS: For these experiments, we exposed mice to histamine intranasally, then counted the number of sneezes and nose rubs as the primary outcome measure of nasal responsiveness. First, we constructed a dose-response curve. Second, we treated the mice with desloratadine, a histamine 1 receptor antagonist, prior to histamine exposure. Third, we challenged, with intranasal histamine, mice made allergic using 2 techniques. Fourth, we infected mice with Streptococcus pneumoniae to determine whether acute sinusitis causes nasal hyperresponsiveness to histamine exposure. RESULTS: Nasal histamine challenge led to a reproducible, dose-dependent increase in sneezing and nose rubs. The response to histamine exposure was blocked by desloratadine (P < or = .05). Allergic mice had a significant increase in responsiveness (P < or = .05) over baseline after exposure to antigen. Mice with acute sinusitis had a sustained increase in responsiveness, although less severe than after allergy, compared with baseline values that lasted 12 days after infection (P < or = .05). CONCLUSIONS: Nasal challenge with histamine is a physiologic test of nasal responsiveness. The hyperresponsiveness of allergic mice to histamine exposure parallels the response to nonspecific stimuli during the human allergic reaction. In addition, we showed that acute bacterial sinusitis causes nasal hyperresponsiveness in mice.  相似文献   
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