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91.
PURPOSE: To review a large single-institution experience in the management of aggressive fibromatosis to determine the effectiveness of external beam radiotherapy (EBRT) and identify the presentation and treatment variables predictive of locoregional control. METHODS AND MATERIALS: Between 1975 and 2000, 72 patients were treated with EBRT for a pathologically confirmed diagnosis of aggressive fibromatosis. Thirty patients were treated at the primary presentation and 42 at the time of a locoregional recurrence. Minimal 2-year follow-up data were available for 65 patients (median 6 years). Megavoltage irradiation with 60Co to 20 MV photons or electron therapy was used for all patients. Most patients were treated after attempted complete surgical resection; 16 patients underwent pretreatment biopsy alone. The prescribed treatment was standard (1.8 Gy) daily fractions in 42 cases and 1.2 Gy fractions b.i.d. in 23 cases. The median prescribed dose was 54 Gy. The prognostic variables and treatment results were evaluated by Kaplan-Meier actuarial analysis. RESULTS: Locoregional control was achieved in 52 of 65 patients. The 5-year actuarial locoregional control was 83%. Locoregional failure occurred in 13 patients (11 in patients with recurrent tumors). Only two failures occurred within the irradiation fields; nine failures occurred at the field margins. Eleven patients were salvaged by surgery: wide excision in nine and amputation in two. The only prognostic factor significant for locoregional control was primary vs. recurrent presentation (p = 0.0193). The 5-year locoregional control rates for irradiation at initial presentation and at recurrence were 96% and 75%, respectively. The variables without significance for locoregional control included primary tumor location, surgical procedures performed, resection margins, and gross vs. microscopic residual tumor at irradiation. Lymphedema was the most common late effect, occurring in 7 patients, 5 with prior treatment. Bone fracture occurred in 3 patients; all 3 had fibromatosis involving the bone at presentation but without recurrence at the time of fracture. CONCLUSION: EBRT is effective treatment for aggressive fibromatosis. The probability of locoregional control decreases with multiple prior recurrences.  相似文献   
92.
BACKGROUND: Acupuncture may improve motor function in patients with chronic hemiparetic stroke, yet the neural mechanisms underlying such an effect are unknown. As part of a sham-controlled, randomized clinical trial testing the efficacy of a 10-week acupuncture protocol in patients with chronic hemiparetic stroke, we examined the relationship between changes in function of the affected upper limb and brain activation using functional magnetic resonance imaging (fMRI). METHODS: Seven (7) chronic hemiparetic stroke patients underwent fMRI and testing of function of the affected upper limb (spasticity and range-of-motion) before and after a 10-week period of verum (N=4) or sham (N=3) acupuncture. The correlation between changes in function of the affected upper limb and brain activation after treatment was tested across patients. RESULTS: We found a significant positive correlation between changes in function of the affected upper limb (spasticity and range of motion) and activation in a region of the ipsilesional motor cortex. Patients treated with verum acupuncture showed a trend toward a greater maximum activation change in this motor cortical area as compared to those treated with sham acupuncture. CONCLUSIONS: Acupuncture may improve function of the affected upper limb in chronic hemiparetic stroke patients by increasing activity in the ipsilesional motor cortex.  相似文献   
93.
HLA and granulocyte-specific antibodies have been implicated in the production of transfusion-related acute lung injury (TRALI). Reported here is a case that suggests that the patient's preexisting condition may play an important role in determining whether TRALI develops upon transfusion of blood products containing anti-white cell (WBC) antibodies. A 29-year-old woman with thrombotic thrombocytopenic purpura (TTP) underwent an uneventful 1.5-volume plasma exchange, which was followed by the transfusion of 2 red cell (RBC) units. At the end of the second RBC transfusion, the patient developed clinical signs and symptoms of noncardiogenic pulmonary edema. Serologic studies demonstrated that the serum from the second RBC donor had no HLA antibodies but did have a granulocyte-specific antibody (anti-NB2) that caused the agglutination of the recipient's granulocytes, which were NB2 positive. Serum from the donor of the first RBC unit and serum from the donors of units used in the exchange had no HLA or granulocyte-specific antibodies that reacted with the recipient's WBCs. Because the donor implicated in this reaction had a history of 21 blood donations, none of which had been associated with a transfusion reaction, we suggest that the patient's preexisting condition played a significant role in this episode of TRALI, owing to the granulocyte-specific antibody.  相似文献   
94.
沙赛普肽注射液的细菌内毒素检测   总被引:2,自引:0,他引:2  
目的:用鲎试剂检测沙赛普肽注射液中的细菌内毒素。方法:采用鲎试法(LT)与家兔法(RT)对沙赛普肽注射液进行细菌内毒素检测。结果:两种方法检查结果一致,用直接稀释法排除细菌内毒素的干扰。结论:以鲎试法用于控制沙赛普注射液的热原方法可行。  相似文献   
95.
Long term chronic calorie restriction (CR) of adult nonhuman primates significantly reduces morbidity and increases median age of death. The present review is focused upon an ongoing study of sustained adult- onset calorie restriction, which has been underway for 15 years. Monkeys, initially calorie restricted at about 10 years of age, are now approximately 25 years old. The median life span of these restricted monkeys is increasing, now exceeding that of ad libitum (AL)-fed monkeys. In our laboratory, maximum life span for AL-fed monkeys appears to be about 40 years. Thus, whether CR can also increase maximal life span, as it does in rodents, cannot be determined for at least another 15 years. The earliest detectable positive benefit on morbidity in these monkeys was previously reported as the prevention of obesity. Current evidence, as reviewed here, suggests that much obesity- associated morbidity is also mitigated by sustained calorie restraint in nonhuman primates. Furthermore, probably because of the prevention of obesity, diabetes has also been prevented. Recent findings include the identification of extraordinary changes in the glycogen synthesis pathway, and on the phosphorylation of glycogen synthase in response to insulin. This calorie restriction-induced prevention of morbidity does not require excessive leanness, but is clearly present when body fat is within the normal range of 10 to 22%, and this is likely to be true in humans as well.   相似文献   
96.
Several studies have identified cyclooxygenase-2 (COX-2) expression in a variety of sarcomas, including rhabdomyosarcoma, osteosarcoma and chondrosarcoma. Although overexpression of COX-2 has been associated with poor prognosis and decreased survival in chondrosarcoma and osteosarcoma, no relationship between COX-2 expression and patient outcome has been demonstrated in rhabdomyosarcoma or adult soft tissue sarcomas. Little is known concerning the expression of COX-2 in synovial sarcoma. Therefore, the aim of this study was to examine the expression of COX-2 in synovial sarcoma and if shown, to identify any association with tumor stage and oncologic outcome. Paraffin-embedded specimens from 27 patients with synovial sarcoma who were treated with surgical resection or biopsy were obtained. Specimens were evaluated for the degree of COX-2 expression after immunohistochemical staining. Specimens were assigned an immunoreactivity score (IS) based on the percent positivity of the specimen. A retrospective chart analysis was performed to determine the clinical stage at presentation, incidence of local recurrence, presence of metastatic disease and overall survival. Statistical analysis was then performed to determine whether there was a significant relationship between IS and stage at presentation or patient outcomes. COX-2 expression was detected in 18 of 27 (66.67%) of the pathological specimens. There was a statistically significant relationship between COX-2 expression and patient clinical stage at presentation; however, we were unable to identify a significant relationship between IS and patient survival. We also found no significant relationship between IS and development of metastases or local recurrence. COX-2 was expressed to some degree in 67% of the tumor specimens. There was a significant relationship between IS and patient stage at presentation, but no significant relationship between COX-2 expression and clinical outcome could be identified. The fact that these tumors do express COX-2, however, suggests the potential for an additional target for more effective therapy.  相似文献   
97.
The protease-activated thrombin receptor-1 (PAR-1) can be activated by both the tethered ligand exposed by thrombin cleavage and a synthetic peptide having the tethered ligand sequence (thrombin receptor agonist peptide or TRAP). We conducted a mutational analysis of extracellular residues of the receptor potentially involved in interaction with both the tethered ligand and the soluble peptide agonist. Agonist-stimulated calcium efflux in X. laevis oocytes or inositol phosphate accumulation in COS-7 cells was used to assess receptor activation. We have also examined the binding of a radiolabeled TRAP for the wild-type and mutant PAR-1 receptors. Our results indicated that most of the mutations strongly affected TRAP-induced responses without significantly altering thrombin-induced responses or TRAP binding. Several point mutations and deletion of extracellular domains (DeltaEC3, DeltaNH3) drastically altered the ability of mutant receptors to respond to TRAP, but not to thrombin, and did not affect the affinity for the radiolabeled TRAP by these mutant receptors. Only mutations that disrupted the putative disulfide bond or substitution of multiple acidic residues in the second extracellular loop by alanine had a significant effect on both ligand binding and thrombin activation. These results suggest that although both agonists can activate PAR-1, there are profound differences in the ability of thrombin and TRAP to activate PAR-1. In addition, we have found PAR-1 mutants with the ability to dissociate receptor-specific binding from functional activity.  相似文献   
98.
Authors with wide experience report that the Shouldice technique for repair of inguinal hernia is very effective. The technique has not gained widespread acceptance or notoriety. For example, the 13th edition of Textbook of Surgery, edited by Sabiston, devotes only one paragraph to this type of herniorrhaphy. Because of the excellent results reported by the Shouldice Clinic, this technique was adopted at the Augusta Veterans Administration Hospital, a teaching hospital of the Medical College of Georgia. Since 1976, a total of 604 Shouldice repairs have been performed by supervised house staff; 468 patients have been followed for up to 8 years and a recurrence rate of 1.3 per cent is reported. Although the follow-up is brief, the Shouldice hernia repair is widely applicable and good results are not dependent on wide experience alone.  相似文献   
99.
BackgroundTo determine whether utilization of a retrieval bag during laparoscopic appendectomy for uncomplicated and complicated appendicitis (perforation/abscess) is associated with postoperative surgical site infection rates.MethodsWe studied patients presented in the database of the 2016 Appendectomy-Targeted American College of Surgeons National Surgical Quality Improvement Program who underwent laparoscopic appendectomy for pathology-confirmed appendicitis. The primary predictor variable was intraoperative utilization of a specimen retrieval bag for removal of the appendix from the peritoneal cavity. The primary outcome variable was 30-day postoperative surgical site infection. Logistic regression analysis was used to determine the association between use of a specimen retrieval bag and postoperative surgical site infection rate after adjustment for patient- and disease-related variables.ResultsA total of 10,357 patients were included for analysis. Of these procedures, 9,585 (92.6%) included the use of a specimen bag and 772 (7.5%) did not. The 30-day incidence of postoperative surgical site infection was 4.2% in the group in which no bag was used and 3.6% in the group in which a bag was used (adjusted odds ratio of surgical site infection with no bag utilization was 1.15 [95% confidence interval 0.78–1.69; P = .49]). The lack of a statistically significant association between bag utilization and postoperative surgical site infection incidence was also demonstrated for a subgroup of patients with perforated appendicitis.ConclusionUtilization of a retrieval bag during laparoscopic appendectomy is not associated with a statistically significant decrease in postoperative surgical site infection for either uncomplicated or complicated acute appendicitis.  相似文献   
100.
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