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排序方式: 共有1766条查询结果,搜索用时 15 毫秒
101.
Diniz G Aktaş S Ortaç R Erbay A Vergin C Ergin M 《The Turkish journal of pediatrics》2004,46(3):239-244
Possible clinical relevance of Nm23 expression, angiogenesis and proliferative activity were evaluated as prognostic parameters in childhood embryonal rhabdomyosarcoma (RMS). Specimens of 25 RMS cases were studied for Nm23 antigen immunohistochemically. Vascular surface density (VSD) and number of vessels per stroma (NVES) calculated by stereologic methods on labeling sections with CD34 antibody. For evaluation of proliferative activity of tumors, mitotic figures and Ki67 positive cells were investigated. All findings were searched statistically. Five patients were stage 1 (20%), two were stage 2 (8%), 15 were stage 3 (60%) and three were stage 4 (12%). The mean event free survival (EFS) was 20.8 and the mean overall survival (OS) was 25.9 months. Sixteen patients (64%) were alive and without disease. The percentage of Nm23 positivity was 52%. Log rank analysis showed Nm23 as a predictor for survival (p=0.0313). In Pearson correlation analysis, there was statistical significance between OS and presence of Nm23 expression (p=0.044). VSD was also positively related with EFS (p=0.040). Despite the present parameters in use, there is a need for new prognostic markers, especially to predict the outcome of patients. These findings suggested that Nm23 expression and VSD might be useful for follow-up in RMS. 相似文献
102.
Case report A 58-year-old male was admitted with headache to our neurosurgery clinic. His neurological examination revealed slight left hemiparesis. The radiological evaluation with contrast administred magnetic resonance imaging (MRI) scan demonstrated a right temporo-parietal ring enhancing mass lesion surrounded by edema which was resembling a typical glioma (Fig. 1). The patient was operated on via a temporo-parietal craniotomy and an arteriovenous malformation surrounded by abnormal glial tissue was observed during the exposure. A nidus supplied by several branches arising from the middle cerebral artery (MCA) was obvious. The venous drainage of the malformation was to the superficial venous system. The observed arterial feeders and the draining vein were coagulated and the nidus was macroscopically totally excised. The frozen examination from surrounding glial tissue revealed a high grade glioma. The tumor was also macroscopically totally excised. Postoperatively, the cerebral angiogram demonstrated a right temporal arteriovenous malformation with a centrally excised nidus. The remaning major feeders involved the angular gyrus and the posterior temporal arteries. The venous drainage was to the straight and sigmoid sinuses (Fig. 2). The final histopathological examination of the specimen revealed an arteriovenous malformation surrounded by a high grade glioma (Fig. 3). The patient refused a second operation for total removal of the AVM. Postoperatively, he is doing well with improvement of his left hemiparesis. 相似文献
103.
We investigated the changes in renal excretion of calcium, sodium, and potassium in asthmatic children treated with inhaled budesonide, an inhaled glucocorticoid. Twenty-two asthmatic patients (7 female, 15 male, mean age 10.1±4.3 years) treated with 400–600 g/day inhaled budesonide and 23 healthy children (6 female, 17 male, mean age 10.2±2.8 years) were enrolled in the study. The parameters recorded were serum sodium, potassium, calcium, phosphorus, alkaline phosphatase (ALP), type I collagen carboxyterminal telopeptide (ICTP), osteocalcin, intact parathyroid hormone (PTH) levels, first spot morning urine calcium/creatinine ratio, sodium/potassium ratio, and daily renal calcium excretion rate (UCa-ER). These parameters were measured in the control group and pre- and post-budesonide treatment in asthmatic children. Serum electrolytes, ALP, PTH, ICTP, and UCa-ER were in the normal ranges and were not significantly different between controls and asthmatic children. Serum levels of ICTP increased, while levels of osteocalcin decreased after budesonide therapy in the asthmatic group (P=0.001, P=0.005). UCa-ER was decreased after budesonide therapy in asthmatics (P=0.000). In conclusion, moderate doses of inhaled budesonide cause hypocalciuria and decreased bone turnover. These results may be attributed to a mechanism compensating for decreased absorption of calcium in the gut due to the topical effect of swallowed budesonide rather than the systemic effects of the drug. Increased bone metabolism and decreased turnover may have an important role in this compensatory mechanism. 相似文献
104.
Duman M Irken G Oren H Uçar C Atabay B Yilmaz S Yüksel F Ozkan H 《Biology of the neonate》2003,84(3):206-213
In this study, we determined the plasma TGF-beta1 levels in healthy and thrombocytopenic and nonthrombocytopenic neonates who had perinatal risk factors and examined the association between plasma TGF-beta1 levels and platelet counts in these newborns to investigate the role of TGF-beta1 in the pathogenesis of neonatal thrombocytopenia. Three groups were defined in this prospective study: group 1, thrombocytopenic neonates (n=22) who had perinatal risk factors; group 2, nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia (n=20); group 3, healthy and nonthrombocytopenic neonates without any risk factors (n=20). Plasma TGF-beta1 levels were measured with ELISA. Plasma TGF-beta1 levels of the thrombocytopenic neonates were significantly lower than those of healthy nonthrombocytopenic neonates but did not differ significantly from nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia. There was a significant positive correlation between plasma TGF-beta1 levels and platelet counts. Further studies are needed to determine the cause of low plasma TGF-beta1 levels in thrombocytopenic neonates and to investigate the role of plasma TGF-beta1 levels in the pathogenesis of neonatal thrombocytopenia. 相似文献
105.
Irken G Oren H Undar B Duman M Gülen H Uçar C Sanli N 《The Turkish journal of pediatrics》2002,44(1):21-24
Turkey is located in a geographic area of the world where thalassemia syndromes and abnormal hemoglobins are common. In this study we aimed to evaluate the thalassemia syndromes and abnormal hemoglobins in patients from the Aegean region of Turkey. Among the patients admitted to our Pediatric Hematology or Hematology Clinic between January 1997-September 1999, hemoglobin electrophoresis of 3,228 cases investigated for anemia was done using high performance liquid chromatography. Beta thalassemia trait was diagnosed in 21.1%, beta thalassemia major in 0.2%, S-beta thalassemia in 0.37%, Hb D in 0.37%, Hb S trait in 0.32%, Hb E in 0.18%, Hb O-Arab in 0.12%, Hb G-Copenhagen in 0.09%, Hb D-Iran in 0.06%, Hb Lepore in 0.06%, Hb Hasharon in 0.03%. Our results demonstrate that people in the Aegean region of Turkey have a wide spectrum of thalassemia syndromes and abnormal hemoglobins. 相似文献
106.
Alehan D Ozkutlu S Ayabakan C Bilgiç A Ozme S Ozer S Celiker A 《The Turkish journal of pediatrics》2002,44(1):5-12
We retrospectively assessed the clinical course and outcome of left-sided endocarditis in pediatric patients to find out the prognostic significance of the presence and size of echocardiographically detected vegetations. Among the children admitted to our institution with endocarditis between January 1987 and October 1999, 16 patients (mean age 9.03 +/- 4.95 years) who met the Duke criteria for the diagnosis of infective endocarditis (IE) were included in this study. Rheumatic valvular disease was the most frequent underlying heart disease (10 patients: 62.5%). Five patients were operated at a mean of 13.9 months before endocarditis, and all had residual defects. Vegetation was detected in 11 cases (69%). Ten patients had major complications (within 2 weeks in 6 patients). Three patients developed congestive heart failure (CHF), six had intracranial and one had lower extremity emboli. Among them four were operated because of complications (CHF: 3 cases, intracranial emboli: 1 case). All the operated cases are doing well. The association between intracranial embolic events and echocardiographically detected vegetations was determined by calculating specificity (40%), sensitivity (100%), positive predictive value (50%), and negative predictive value (100%). No intracranial embolism occurred in patients without vegetations. All vegetations were < or = 6 mm in patients with systemic embolism. There were four deaths, three of which were because of intracranial embolism. This study suggests that intracranial emboli have a major risk of mortality in left-sided endocarditis. The larger size of the vegetation is not a predictor of complications; furthermore, the absence of vegetations predicts that the patient is safe from embolic events. Therefore all patients with left-sided IE should be considered for earlier surgical intervention. 相似文献
107.
A case of dens invaginatus in a mandibular second primary molar of an eleven-year-old boy is presented. The tooth was extracted and examined by scanning electron microscopy. SEM findings demonstrated the presence of defective enamel and cementum in the pulp chamber. Dentinal tissues were also irregular and had fewer and thinner tubules. This case of dens invaginatus in primary molar is an unusual case of the malformation being the only one in the literature. 相似文献
108.
Ercan F Cetinel S Erin N Aydin H Hürdağ C Parker T Parker K Mayhew T 《Urologia internationalis》2003,71(4):393-398
INTRODUCTION: We have investigated the volume of nerve fibers in the rat urinary bladder following systematic exposure to cold-restraint stress and capsaicin treatment. MATERIALS AND METHODS: Adult Wistar albino rats were either exposed to cold-restraint stress (vehicle group) or treated with capsaicin before exposure to cold-restraint stress (capsaicin group). In the control group, animals were neither exposed to cold-restraint stress nor given capsaicin. From each group, samples of bladder were prepared for morphological investigation and stereological evaluation of the volume of nerve fibers. RESULTS: Stress exposure was associated with urothelial degeneration, a higher incidence and degranulation of mast cell profiles in the mucosa, and an increased volume of nerve fibers in the muscular layer of the bladder wall. Capsaicin treatment prevented the stress-induced degenerative changes. In the capsaicin group, the volume of nerve fibers in the muscular layer was also significantly smaller than that in the stress group. CONCLUSIONS: Exposure of adult rats to capsaicin prevented the stress-induced degeneration of the bladder and changed the volume of capsaicin-sensitive fibers in muscular layer. We conclude that capsaicin and related compounds may be useful in treating stress-induced bladder problems. 相似文献
109.
Gürdal C Aydin S Kirimlioğlu H Toprak E Sengör T 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2003,217(5):329-336
PURPOSE: New contact lens materials with high oxygen permeability are said to be convenient for the extended-wear (EW) schedule. We evaluated the short-term effect of EW soft contact lens usage on ocular surface and central corneal thickness. PATIENTS AND METHODS: Fifty-two eyes of 26 patients were included in the study. Sixteen of the patients used the high oxygen-permeable lenses for a 30-day extended-wear schedule (group I). Ten patients used the lenses on a daily wear basis (DW, group II). All patients were evaluated for visual acuity and central corneal thickness by corneal and conjunctival biomicroscopy, Schirmer and tear break-up time (BUT) tests. Impression cytology was performed in the superior/temporal, inferior/nasal quadrants of the conjunctiva, 1 mm from the limbus, with cellulose acetate filter paper. The specimens were graded under light microscopy according to Nelson's classification. RESULTS: Three patients in the EW group were excluded from the study as they discontinued lens usage due to slight discomfort and hyperemia. Biomicroscopic findings and tear function tests indicated no increased pathological results. Central corneal thickness decreased from 554 +/- 9.55 to 546 +/- 9.30 microm (mean +/- SEM) in the EW group (p = 0.002), whereas no significant change occurred in the DW group. Cytological evaluation of the EW group showed an 88% increase in metaplasia (p = 0.007), especially close to the limbal areas and in the superior quadrants; this ratio was 30% in the DW group. Snake-like chromatin changes were found to be increased, from 4 to 6 patients, in the EW group while it remained the same in the DW group (p > 0.05). Individual comparisons of the initial and final pathological conditions of the ocular surfaces in the two groups showed that there was an increase in pathology in the EW group while there was no significant difference in the DW group. CONCLUSIONS: On a 30-day extended-wear basis with high oxygen-permeable lenses, the possible development and increase of conjunctival cytologic changes secondary to mechanical trauma is one of the main remaining problems. Conjunctival and related immunologic pathologies should not be overlooked when prescribing an extended-wear lens schedule. 相似文献
110.
Yalcinkaya F Ergin C Agalar C Kaya S Aksoylar MY 《International journal of environmental health research》2003,13(1):95-98
Monitoring of Vibrio species by blue crabs (Callinectes sapidus) was carried out during the winter period in a selected area of the Belek, Antalya Gulf. Eighty-three blue crabs were examined for Vibrio species. V. alginolyticus (30.1%), V. fluvialis (10.8%), V. damsela (9.6%), V. harveyi (3.6%), V. metschnikovii (3.6%) and V. vulnificus (2.4%) were isolated. V. vulnificus was the highest concentration (5 x 10(8) Vibrio ml(-1)) although it was only 2.4% isolated from blue crabs. The strains of different vibrio species were highly susceptible to doxycycline, tetracycline and ciprofloxacin. 相似文献