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991.
Ancient change in a schwannoma is a histological variant typically found in longstanding tumors. Histologically, the tumor has biphasic features typical of a schwannoma with evidence of degenerative changes that may complicate diagnosis. The authors report on a 23-year-old man with no features of neurofibromatosis who presented with headaches, blurred vision, and ataxic gait. Magnetic resonance imaging demonstrated a rim-enhancing lesion in the cerebellopontine angle with displacement of brainstem structures and no supratentorial hydrocephalus. Using a lateral suboccipital approach together with image guidance and intraoperative neurophysiological monitoring, a gross-total macroscopic excision was performed. At surgery, the tumor was found to arise from the inferior division of the trigeminal nerve. The final histological diagnosis was schwannoma with ancient change. Note that ancient change in schwannomas is a histological variant thought to result from degenerative changes in longstanding tumors. To the authors' knowledge, this is the first independent report of this histological variant in an intracranial schwannoma.  相似文献   
992.
993.
Detection of thyroid carcinoma in wall of a cystic lesion by FDG PET   总被引:2,自引:0,他引:2  
PURPOSE: Three cases are described, in which positron emission tomography (PET) led to the diagnosis of carcinoma in solitary thyroid nodules (STN), which were considered benign by clinical assessment, ultrasonography, and fine needle aspiration cytology (FNAC). MATERIALS AND METHODS: These 3 cases were from a group of 51 patients with solitary thyroid nodules that were nonfunctioning or "cold" on pertechnetate scans that were later studied with FDG PET scanning. RESULTS: Of the entire group, 28 patients showed the nodule to be nonfunctioning on FDG scans. Of these, 3 showed one or more small foci of intense FDG uptake in the periphery. On histopathology, these sites were found to harbor carcinoma, papillary carcinoma in 2 patients and a follicular variant of papillary carcinoma in one. CONCLUSIONS: These cases demonstrate the usefulness of FDG PET in detection of cancer that may lurk in the wall of a cystic thyroid nodule, often misinterpreted as benign by conventional methods.  相似文献   
994.
995.
OBJECTIVES: (1) To determine a normal range for urinary citrate for term babies. (2) To compare urinary citrate measured in ex preterm babies at term with this normal range. (3) To evaluate whether urinary citrate was related to presence of nephrocalcinosis (NC) and chronic Lung Disease (CLD) in these ex preterm babies. STUDY DESIGN: Urinary citrate was measured in 38 healthy term babies (mean birth weight 3.52 kg, mean gestation 41 weeks) at a mean postnatal age of 3 days (1-5 days) and in 53 ex preterm babies (<32 weeks gestation at birth) at term. These preterm babies were part of a larger study on NC in which two renal ultrasound scans were performed at 1 month and term. RESULTS: The normal range for urinary citrate in term babies was 0.025-2.97 (mean 1.03) mmol/l and citrate/creatinine ratio 0.0011-0.852 (mean 0.27). In the ex-preterm urinary citrate was not significantly different (mean 1.1 vs. 1.03, p=0.7232) but urine citrate /creatinine ratio was significantly higher (mean 1.27 vs. 0.27, p=0.0005). There was no significant difference in urinary citrate or ratios of citrate/creatinine and calcium/citrate in the 11 (20.7%) with NC or in the 17 (32%) babies with CLD. There was no significant relationship found between duration of TPN and urinary citrate measured at term. CONCLUSION: We have determined a normal range for urinary citrate in healthy term babies in the first week of life. The range was very wide. Ex preterm babies had similar values at term and there was no association between urinary citrate and NC or CLD.  相似文献   
996.
A human papillomavirus (HPV) multiplexed competitive Luminex immunoassay first described by Opalka et al. (D. Opalka, C. E. Lachman, S. A. MacMullen, K. U. Jansen, J. F. Smith, N. Chirmule, and M. T. Esser, Clin. Diagn. Lab. Immunol. 10:108--15, 2003) was optimized and validated for use in epidemiology studies and vaccine clinical trials. Optimization increased both the analytical sensitivity and the clinical specificity of the assay to more effectively discriminate the low-titer antibody response of HPV-infected persons from noninfected individuals. The characteristics of the assay that were optimized included monoclonal antibody (MAb) specificity, scaling up the conjugation of virus-like particles (VLPs) to microspheres, VLP concentration, MAb concentration, sample matrix, sample dilution, incubation time, heat inactivation of sample sera, and detergent effects on assay buffer. The assay was automated by use of a TECAN Genesis Workstation, thus improving assay throughput, reproducibility, and operator safety. Following optimization, the assay was validated using several distinct serum panels from individuals determined to be at low and high risk for HPV infection. The validated assay was then used to determine the clinical serostatus cutoff. This high-throughput assay has proven useful for performing epidemiology studies and evaluating the efficacy of prophylactic HPV vaccines.  相似文献   
997.
A rare and unique variant of breast cancer--metaplastic matrix producing carcinoma, is presented. Surgery has been the mainstay of treatment. The role of adjuvant postoperative radiotherapy, as has been used in this patient, has been reviewed.  相似文献   
998.
OBJECTIVE: To evaluate the predictive value of serial changes in micronuclei induction during external radiotherapy (EXRT) in cervical cancer with respect to local response at the end of EXRT and local disease free survival (LDFS). METHODS: Twenty-five patients of squamous cell cancer of the cervix were treated by 50 Gy of EXRT delivered over 5 weeks followed by intracavitary brachytherapy. Serial cytological smears were taken from cervical growth at weekly intervals during the course of EXRT and stained by Giemsa and May-Grunwald's stain. Micronuclei induction were scored as (a) number of cells expressing micronuclei (MN), and (b) total number of micronuclei (TMN) in 1000 tumor cells from each of the serial smears. RESULTS: A significant rise in micronuclei count was seen for both MN and TMN from pretreatment (week 0) to successive weeks of EXRT. For those having a near total tumor regression by end of EXRT, a significant rise in micronuclei was evident even at the end of first week of EXRT (MN: P = 0.05, TMN: P = 0.04). A superior LDFS was observed in patients showing greater than 50% increment in MN value in the first week (median survival for <50% vs. > or =50% rise: 5 months vs. not reached, P = 0.21), while it reached significance for a similar rise of TMN (median survival <50% vs. > or =50% rise: 5 months vs. not reached, P = 0.04). CONCLUSIONS: The significant rise of micronuclei at the end of first week of EXRT in cervical cancers as observed from serial cytological smears could predict for a better local response and LDFS.  相似文献   
999.
A new technique known as tissue dye densitometry (TDD) has been developed to simultaneously measure cerebral blood volume (CBV) and total circulating blood volume (TCV) using near infrared (NIR) spatially resolved spectroscopy (SRS) and the injection of indocyanine green (ICG). Using a medical NIR spectrometer with SRS capability (NIRO-300, Hamamatsu KK), a new parameter is calculated known as the ICG Hb index (IHI), which represents the ratio of ICG concentration to Hb concentration in tissue. Acting as a tracer, ICG is cleared by the liver over 15 min, providing a change of tracer concentration (DeltaCICG,tis), which allows the calculation of the total Hb concentration in tissue (tcHb) using the equation: tcHbtis (micro molar) = DeltaCICG,tis/DeltaIHI. The CBV can subsequently be calculated from tcHbtis given the absolute Hb concentration in blood (g/dL), from which the ICG concentration in blood (DeltaCICG,bl) is obtained. By back-extrapolating the DeltaCICG,bl curve to the peak time, the initial ICG concentration in tissue blood (C0ICG,bl) can be found and TCV can then be calculated. The TCV of 17 neonates were measured using the TDD technique and for comparison using the previously reported fetal Hb dilution technique (FHD). The mean TCV measured by the FHD and TDD techniques were 70.19 +/- 13.73 mL/kg and 70.80 +/- 32.54 mL/kg. The Bland Altman plot showed that the bias was 0.61 +/- 34.34 mL/kg and limits of agreement (2 SD) were -68.07 mL/kg and 69.30 mL/kg. The agreement is limited and the TDD technique needs further validation and development for use in a clinical environment.  相似文献   
1000.
Urinary levels of insecticide metabolites and DNA damage in human sperm   总被引:8,自引:0,他引:8  
BACKGROUND: Members of the general population are exposed to non-persistent insecticides at low levels. The present study explored whether environmental exposures to carbaryl and chlorpyrifos are associated with DNA damage in human sperm. METHODS: Subjects (n=260) were recruited through a Massachusetts infertility clinic. Individual exposures were measured as spot urinary metabolite concentrations of chlorpyrifos [3,5,6-trichloro-2-pyridinol (TCPY)] and carbaryl [1-naphthol (1N)], adjusted using specific gravity. Sperm DNA integrity was assessed by neutral comet assay and reported as comet extent, percentage DNA in comet tail (Tail%) and tail distributed moment (TDM). RESULTS: A statistically significant increase in Tail% was found for an interquartile range (IQR) increase in both 1N [coefficient=4.1; 95% confidence interval (CI) 1.9-6.3] and TCPY (2.8; 0.9-4.6), while a decrease in TDM was associated with IQR changes in 1N (-2.2; -4.9 to 0.5) and TCPY (-2.5; -4.7 to -0.2). A negative correlation between Tail% and TDM was present only when stratified by comet extent, suggesting that Tail% and TDM may measure different types of DNA damage within comet extent strata. CONCLUSIONS: Environmental exposure to carbaryl and chlorpyrifos may be associated with increased DNA damage in human sperm, as indicated by a change in comet assay parameters.  相似文献   
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