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1.
Various techniques are used to collect specimens from the nasal mucosa for morphologic and biochemical analysis. The purpose of this study was to devise a method that overcomes some of the disadvantages (e.g., invasive procedure, samples not suitable for cytologic and biochemical analysis, lack of standardization, and poor reproducibility) of these techniques. The new method requires subjects, with neck extended, to inhale an ultrasonic nebulization of a hypertonic (3% NaCl) solution (UNHS) for 5 min. They then blow their nose into a Petri dish, one nostril at a time with the other one blocked. The secretions are dispersed with 0.1% dithiothreitol in phosphate buffer solution for 20 min. Total cell count (TCC) is evaluated, and the cellular suspension is divided into two aliquots: one is centrifuged and the supernatants are collected for eosinophil cationic protein (ECP) measurements; the other is cytocentrifuged and the slides, stained with Diff-Quik, are used for differential cell count. The results obtained with the UNHS and nasal lavage (NL) methods were compared. Eleven nonatopic healthy subjects and 19 allergic rhinitic patients were studied. Total cell count (×105) was significantly higher with UNHS than with NL (13.0±12.3 vs 1.911.6; P<0.0]) The differential cell count was similar with the two procedures. ECP levels (μg/l) were higher with UNHS than with NL (39.1+38.2 V.S 16.7±41.2; P<0.01). For evaluation of reproducibility, four healthy and six rhinitic subjects underwent UNHS on two occasions within 5 days, and the results of two samples (sample 1 vs sample 2) were analyzed. Reproducibility was good as to TCC, differential cell count, and ECP  相似文献   
2.
Summary 26 patients with astrocytoma grade 11–111, and 36 with malignant glioma (astrocytoma grade IV or glioblastoma) were submitted three days after surgery to a cycle of combination chemotherapy, including BCNU, VCR, PCZ (BVP). Eighteen days after surgery, patients received 40 Gy (astrocytoma grade 11–111) or 45 Gy (malignant glioma) of megavoltage whole-brain irradiation, with an additional boost to the tumor bed of 20 Gy, delivered in 6 weeks. Vincristine was injected weekly during radiotherapy. At the end of radiotherapy, patients received BVP every 6 weeks for at least 8 cycles or until a recurrence or progressive disease. Performance status of grade 1 or 2 was achieved in 15 (60%) and in 5 (20%), respectively, of patients with astrocytoma grade 11–111 after 6 months, and in 6 ps. (29%) and in 9 ps. (42%) after 12 months of follow-up. Only 2 (5.5%) and 18 (64%) patients with malignant glioma achieved a performance status of grade 1 or 2 after 6 months, and these proportions are 6% and 35%, respectively, after 12 months. After a 5-year follow-up, 59% of patients with astrocytoma are still alive, with a median survival time of 60+ months, whereas only 4% of patients with malignant glioma are alive, with a median of 11.2 months.  相似文献   
3.
The RET gene encodes a single-pass transmembrane receptor tyrosine kinase. RET is the oncogene that causes papillary thyroid carcinoma and medullary thyroid carcinoma. The latter may arise as a component of multiple endocrine neoplasia type 2 syndromes; germline mutations in RET are responsible for multiple endocrine neoplasia type 2 inheritance. In this report we review data on the mechanisms leading to RET oncogenic conversion and on RET targeting as a strategy in thyroid cancer treatment.  相似文献   
4.
Gain-of-function RET mutations are responsible for multiple endocrine neoplasia syndromes (MEN) 2A and 2B and familial medullary thyroid carcinoma (FMTC), whereas loss-of-function mutations are found in Hirschsprung disease. We report a new RET point mutation [R694Q (CGG-->CAG)], serendipitously found in a 23-yr-old woman with hypothyroidism due to atrophic Hashimoto's thyroiditis and primary ovarian failure, without altered calcitonin secretion. Familial history and clinical and biochemical evaluation of first-degree relatives were negative for FMTC, MEN 2A and 2B, and Hirschsprung disease. Genetic analysis showed that the mutation was inherited from the mother, who was submitted 2 yr before to thyroidectomy for goitrous Hashimoto's thyroiditis. Histological revision and immunohistochemical studies documented normal C cell number and morphology. We cloned the mutation in an expression vector encoding a full-length RET protein. The construct was transiently expressed in 293T cells in parallel with a wild-type RET and a C634R MEN 2A-associated RET mutant. Proteins were harvested from transfected cells, and tyrosine phosphorylation levels were assayed. The mutation did not exert significant potentiating effects on RET kinase. A focus assay was also performed on NIH3T3 fibroblasts; the mutant did not exert significant transforming activity.In conclusion, a new RET mutation was found in two subjects without any evidence of MEN and FMTC. In keeping with clinical data, transfection studies confirmed lack of activating activity. This serendipitous discovery, apparently devoid of oncogenic potential, underscores the problems that may be encountered in genomic studies on RET.  相似文献   
5.
Musculoskeletal computer models allow us to quantitatively relate morphological features to biomechanical performance. In non-human apes, certain morphological features have long been linked to greater arm abduction potential and increased arm-raising performance, compared to humans. Here, we present the first musculoskeletal model of a western lowland gorilla shoulder to test some of these long-standing proposals. Estimates of moment arms and moments of the glenohumeral abductors (deltoid, supraspinatus and infraspinatus muscles) over arm abduction were conducted for the gorilla model and a previously published human shoulder model. Contrary to previous assumptions, we found that overall glenohumeral abduction potential is similar between Gorilla and Homo. However, gorillas differ by maintaining high abduction moment capacity with the arm raised above horizontal. This difference is linked to a disparity in soft tissue properties, indicating that scapular morphological features like a cranially oriented scapular spine and glenoid do not enhance the abductor function of the gorilla glenohumeral muscles. A functional enhancement due to differences in skeletal morphology was only demonstrated in the gorilla supraspinatus muscle. Contrary to earlier ideas linking a more obliquely oriented scapular spine to greater supraspinatus leverage, our results suggest that increased lateral projection of the greater tubercle of the humerus accounts for the greater biomechanical performance in Gorilla. This study enhances our understanding of the evolution of gorilla locomotion, as well as providing greater insight into the general interaction between anatomy, function and locomotor biomechanics.  相似文献   
6.
7.
The immunocytochemical detection of multidrug-resistance (MDR) associated P-glycoprotein (P-170) was longitudinally performed on bone marrow smears from 32 responsive patients with acute leukaemia in the different phases of the disease (at diagnosis, in complete remission, at relapse) by means of APAAP technique and monoclonal antibody C219. The whole group of eight patients with presence of P-170 positive cells while in complete remission rapidly relapsed with a high proportion of blasts showing MDR phenotype; they were resistant to further treatments. Twelve out of 24 subjects without cells with MDR phenotype in complete remission remained in this condition, six had a responsive relapse (without significant expression of P-170 in 5/6 patients) and six a resistant relapse. Four patients of this last group significantly expressed P-170. Our data indicate that the detection of scattered P-170 positive cells during complete remission might identify a subset of leukaemic patients with high risk of early and resistant relapse.  相似文献   
8.
OBJECTIVESAmong patients undergoing transcatheter mitral valve repair with the MitraClip device, a relevant proportion (2–6%) requires open mitral valve surgery within 1 year after unsuccessful clip implantation. The goal of this review is to pool data from different reports to provide a comprehensive overview of mitral valve surgery outcomes after the MitraClip procedure and estimate in-hospital and follow-up mortality. Open in a separate windowMETHODSAll published clinical studies reporting on surgical intervention for a failed MitraClip procedure were evaluated for inclusion in this meta-analysis. The primary study outcome was in-hospital mortality. Secondary outcomes were in-hospital adverse events and follow-up mortality. Pooled estimate rates and 95% confidence intervals (CIs) of study outcomes were calculated using a DerSimionian–Laird binary random-effects model. To assess heterogeneity across studies, we used the Cochrane Q statistic to compute I2 values.RESULTSOverall, 20 reports were included, comprising 172 patients. Mean age was 70.5 years (95% CI 67.2–73.7 years). The underlying mitral valve disease was functional mitral regurgitation in 50% and degenerative mitral regurgitation in 49% of cases. The indication for surgery was persistent or recurrent mitral regurgitation (grade >2) in 93% of patients, whereas 6% of patients presented with mitral stenosis. At the time of the operation, 80% of patients presented in New York Heart Association functional class III–IV. Despite favourable intraoperative results, in-hospital mortality was 15%. The rate of periprocedural cerebrovascular accidents was 6%. At a mean follow-up of 12 months, all-cause death was 26.5%. Mitral valve replacement was most commonly required because the possibility of valve repair was jeopardized, likely due to severe valve injury after clip implantation.CONCLUSIONSSurgical intervention after failed transcatheter mitral valve intervention is burdened by high in-hospital and 1-year mortality, which reflects reflecting the high-risk baseline profile of the patients. Mitral valve replacement is usually required due to leaflet injury.  相似文献   
9.
PurposeTo investigate the course of inherited retinal degenerations (IRD) due to mutations in the RPE65 gene.MethodsThis longitudinal multicentric retrospective chart-review study was designed to collect best corrected visual acuity (BCVA), Goldman visual field, optical coherence tomography (OCT), and electroretinography (ERG) measurements. The data, including imaging, were collected using an electronic clinical research form and were reviewed at a single center to improve consistency.ResultsFrom an overall cohort of 60 Italian patients with RPE65-associated IRD, 43 patients (mean age, 27.8 ± 19.7 years) were included and showed a mean BCVA of 2.0 ± 1.0 logMAR. Time-to-event analysis revealed a median age of 33.8 years and 41.4 years to reach low vision and blindness based on BCVA, respectively. ERG (available for 34 patients) showed undetectable responses in most patients (26; 76.5%). OCT (available for 31 patients) revealed epiretinal membranes in five patients (16.1%). Central foveal thickness significantly decreased with age at a mean annual rate of −0.6%/y (P = 0.044). We identified 43 different variants in the RPE65 gene in the entire cohort. Nine variants were novel. Finally, to assess genotype-phenotype correlations, patients were stratified according to the number of RPE65 loss-of-function (LoF) alleles. Patients without LoF variants showed significantly (P < 0.05) better BCVA compared to patients with one or two LoF alleles.ConclusionsWe described the natural course of RPE65-associated IRD in an Italian cohort showing for the first time a specific genotype-phenotype association. Our findings can contribute to a better management of RPE65-associated IRD patients.  相似文献   
10.
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