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71.
Summary The ultrastructure of the cytoskeleton of cultured mouse hepatocytes was studied by a quick-freezing and deep-etching method. Isolated mouse hepatocytes were cultured on collagen gels for 48 h, fixed in paraformaldehyde and centrifuged to prepare cell pellets. The hepatocytes were split open to remove cytoplasmic soluble proteins for replica preparations. Some specimens were decorated with anti-actin antibody or S1 myosin fragments to identify actin filaments. They were quickly frozen in isopentane-propane mixture, fractured in liquid nitrogen, deeply etched in a freeze-fracture machine and rotary shadowed by platinum and carbon. The basal cell membranes of hepatocytes were in contact with the collagen gels and the apical surface faced the culture medium. Networks of actin filaments were attached to the apical cell membranes, but intermediate filaments were localized along the basal layer. Some intermediate filaments were associated with cell organelles, such as the endoplasmic reticulum. The Golgi apparatus was less associated with the cytoskeleton and showed synthesized materials in the cisternae. Cytoskeletal organization in cultured hepatocytes was revealed three-dimensionally, indicating that the interaction of cell membranes with collagen gels is important for the organization of the cytoskeleton.  相似文献   
72.
PURPOSETo examine medium-term outcomes of hemi-gland low-dose-rate brachytherapy as a primary treatment for intermediate-risk prostate cancer.METHODSWe recruited intermediate-risk unilateral prostate cancer patients for a prospective trial of hemi-gland brachytherapy. Twenty-four patients underwent hemi-gland iodine-125 seed implantation with a prescribed dose of 160 Gy. Serum prostate-specific antigen (PSA) was measured regularly and follow-up biopsy was scheduled after 2–3 years of treatment. When clinically needed afterward, for-cause biopsy was performed to confirm pathology. Treatment failure (TF)-free survival, which was defined as freedom from radical or systemic therapy, metastases, and cancer-specific mortality, was assessed, as was biochemical failure (BF)-free survival. Urinary and sexual functions were also evaluated.RESULTSMedian follow-up duration was 61 months. Twenty-two patients (92%) exhibited a declining trend or decreased value of PSA for 12 months or longer after the treatment. Follow-up biopsy in the initial triennium and for-cause biopsy in the subsequent triennium were performed in 16 and four patients, respectively, and cancer was found from the treated lobe in one patient (4% of the cohort) and significant cancer was found from untreated lobes in four patients (17%) in total. Secondary treatments were performed in six patients successfully. Five-year freedom from BF, TF, and metastasis was 71%, 90%, and 100%, respectively. The International Prostate Symptom Score significantly deteriorated at 3 months and reversed itself afterward. The International Index of Erectile Function 5 had no significant decrease.CONCLUSIONSHemi-gland low-dose-rate brachytherapy provides favorable medium-term oncological outcomes with genito-urinary functional preservation for men with intermediate-risk unilateral prostate cancer.  相似文献   
73.
Management of infected aortic aneurysms, which can be life-threatening, remains challenging. Open surgical treatments, including debridement of the infected aorta and the surrounding tissue and either in situ reconstruction or extra-anatomic bypass covering with omentum or muscle flap, are the mainstay of therapy. However, increasing advances in technology have made endovascular treatment of infected aneurysms feasible. The present study describes the first clinical report of successful treatment of an infected aneurysm using endovascular techniques in the acute phase, followed by delayed open surgery.  相似文献   
74.
Purpose  Several recent reports have discussed refrozen and thawed embryo transfer; however, the process may cause a degree of chromosomal damage and subtle genomic mutation. In view of this possibility, the purpose of this study was to investigate the incidence of aneuploidy in refrozen embryos. Methods  In order to investigate the incidence of aneuploidy and mosaicism observed in chromosome 1, fluorescent in situ hybridization (FISH) was used on surviving embryos that first underwent one freeze-thaw cycle, then were allowed to develop to the blastocyst stage, and subsequently survived a second freeze-thaw cycle. Results  Of 1,132 blastomeric nuclei analyzed from 15 refrozen embryos, disomy was found in 82.9%. In contrast, for the 11 blastocysts subjected to only one freeze-thaw cycle, disomy was noted in 78.4%. Of the 197 blastomeric nuclei analyzed in all arrested embryos, disomy was found in 51.8%. Conclusions  The refreezing process did not increase aneuploidy. The good and fair morphology groups demonstrated a higher percentage of disomy than the poor morphology group regardless of whether they were frozen once or twice.  相似文献   
75.
76.
Purpose To report the outcome of transcorneal electrical stimulation (TES) of the visual system on long-standing retinal artery occlusion (RAO). Design Open labeled, case series. Patients and methods Two patients with central RAO (15 and 33 months respectively) and one with branch RAO (26 months) underwent TES therapy. Subjective and objective ophthalmological evaluations were performed before and after the TES. The ages of the patients were 38, 49, and 63 years. The TES (20 Hz biphasic pulses, 30 minutes, up to 1100 uA) was delivered by a bipolar contact lens electrode once a month for 3 months. Perimetric and/or electrophysiological examinations were performed as outcome measures. Results The visual acuity improved by more than 0.2 logMAR units in two cases, and the visual fields were improved in all three cases. The multifocal ERGs which had been reduced in the loci corresponding to the ischemic retinal area were improved after the treatment in two cases. Neither ocular nor systemic adverse effects were observed except for transient superficial keratitis. Conclusions TES of the retina can improve retinal function in eyes with long-standing RAOs. None of the authors have any financial or proprietary interest in any material or methods mentioned. This study was supported by Researches on Sensory and Communicative Disorders from the Ministry of Health, Labor, and Welfare, Japan.  相似文献   
77.
Aim: Differential diagnosis, including the respective distinctions between benign and malignant tumors, follicular and papillary neoplasms, and follicular adenoma and follicular carcinoma, are always required in clinical practice, because therapeutic strategy largely depends on the diagnosis made. Methods: The present study describes a novel approach to obtaining clinically useful markers by means of the simultaneous comparison of multiple molecules using tissue array analysis. The markers examined in this study include galectin‐3, CD44v6, p53, HBME‐1, maspin and S100A4, which were reportedly useful for making these distinctions in association with metastasis and invasion. A total of 45 cases of thyroid tumors (seven adenomatous goiters, 16 follicular adenomas, 12 follicular carcinomas and 10 papillary carcinomas) were analyzed. Results: The results demonstrated the following suggestive phenotypes: galectin‐3, HBME‐1 and maspin+ as benign lesions, galection‐3, HBME‐1+ and maspin as follicular carcinoma, and galectin‐3+, HBME‐1+ and maspin+ as papillary carcinoma. Conclusions: The expression of the molecules was assessed in each case and the expression profiles were compared. Useful multiple molecules were selected for each distinction and were correlated with each other. To understand the complex relationship, a logistic regression model was constructed. These results suggested that combined analysis of multiple molecules enhanced the differential diagnostic accuracy.  相似文献   
78.
79.
We describe a 37-year-old man complaining of right back pain and gait disturbance. He had a big soft tumor on his right back, hemihypertrophy of the right lower extremity, and right thoracic scoliosis. We diagnosed Klippel-Trenaunay-Weber syndrome based on the pathological findings of the soft tumor. Computed tomography (CT) scan revealed severe spinal stenosis due to a hypertrophic vertebral body and facet joint at T7. Treatment by decompression of hypertrophic bone led to complete neurological recovery. To our knowledge, no case has been reported of Klippel-Trenaunay-Weber syndrome with myelopathy which originated from thoracic scoliosis with a hypertrophic facet joint and vertebral body. We suggest that the cause of myelopathy in Klippel-Trenaunay-Weber syndrome originated not only from arteriovenous fistula, medullary angioma, and extradural hemangioma but also vertebral hypertrophy with scoliosis.  相似文献   
80.
PURPOSE: It is known that even after visual loss, younger patients with Leber's hereditary optic neuropathy (LHON) can recover vision. The purpose of this study was to determine the mean age at onset for LHON patients with and without visual recovery who carried the 11778 mutation, and to determine the pattern of central vision recovery. METHODS: Thirty-five LHON patients with the 11778 mutation of mitochondrial DNA who had visited the Keio University Hospital between 1980 and 1999 and were followed for 2 to 20 years, were the subjects of this retrospective study. The patients who had recovered vision were tested by Goldmann perimetry, Humphrey perimetry, and landmark-driven fundus microperimetry with a scanning laser ophthalmoscope (SLO). The fixation status was assessed by SLO microperimetry. RESULTS: Nine of the 35 patients (14 of 70 eyes) demonstrated a recovery of visual acuity to better than 0.3 in at least one eye. The mean age of disease onset was 15.9 +/- 4.6 years in patients with visual recovery and 25.5 +/- 8.9 years in patients without visual recovery. This difference in the mean age at onset was significant (P =.0001; Welch t-test). These 9 patients (14 eyes) showed fenestrated central scotomas in testing by Humphrey 10-2 threshold and SLO microperimetry. The nasal side of the central visual fields had a higher sensitivity than the temporal side in 7 of the 9 patients in Humphrey 10-2 threshold testing. Areas insensitive to 0 dB were detected on the nasal side of the central retina in these patients by SLO microperimetry, and fixation stability was related to the degree of clinical visual acuity. CONCLUSION: The LHON patients with the 11778 mutation and a younger age of onset were more likely to show visual recovery. The findings made by perimetry suggest that the nerve fiber bundles in the nasal field (retina temporal to the fovea) may have a greater potential to recover function in LHON patients.  相似文献   
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