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1.
Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease.  相似文献   
2.
The synthesis of full and semi interpenetrating networks (IPNs) based on poly(dimethy1-siloxane) (PDMS)/polystyrene, PDMS/polybutadiene and PDMS/poly(glycerylpropoxytriacry-late) 1
  • 1 Glycerylpropoxytriacrylate (GFTA):
  • is described. PDMS was used as host polymer in most cases. PDMS networks were prepared with two prepolymers having different number-average molecular weights between junctions, M?c = 15 · l03 and M?c = 75 · l03. Physical properties of IPN samples such as stress-strain behaviour, swelling and glass transition temperature (Tg) were examined. IPNs of both PDMS/polystyrene and PDMS/poly(glycerylpropoxytriacrylate) exhibit superior mechanical and elastomeric properties with respect to pure PDMS network. Most of the IPN systems studied in this work display two Tgs and indicate phase separation.  相似文献   
    3.
    In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats.  相似文献   
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    6.
    OBJECTIVE: The present study was carried out to evaluate the safety and immunogenicity of the Haemophilus influenzae type b-CRM197 (Hib-CRM197) conjugate vaccine in relation to the change of adjuvant from aluminum hydroxide to aluminum phosphate (AlPO4). METHODS: The present study was a clinical phase II, observer-blind, randomized, multicenter, controlled study. Subjects were healthy infants aged 6-12 weeks, eligible for expanded program of immunization (EPI) routine vaccination and admitted to Hacettepe University Department of Social Pediatrics and Gülveren Health Center, Ankara. A total of 520 healthy infants were randomized in a 2:2:1 ratio to receive at either Chiron Hib/AlPO4 vaccine or VaxemHib (aluminum hydroxide adjuvant) vaccine or HibTiter (no adjuvant). Vaccines were administered simultaneously with routine diphtheria, tetanus and pertussis (DTaP) and oral polio vaccine (OPV) vaccines at 2, 4 and 6 months of age. Blood samples for anti-plain polysaccharide (PRP) antibody measurement were collected before the first vaccination and 1 month after the last vaccination. After each vaccination parents filled out a diary for 7 days. RESULTS: Out of 520 subjects enrolled, 514 received three doses and were included for safety analysis. Local and systemic reactions occurred with low and similar frequencies in all groups. Only erythema was more common in Chiron Hib/AlPO4 vaccine (19, 10, 11% in Chiron Hib/AlPO4, VaxemHib and HibTiter, respectively, P < 0.05). Nine serious adverse events were reported in seven cases of which none were related to vaccines. A total of 504 subjects were included in the immunogenicity analysis. The three vaccines were highly immunogenic and equivalent in terms of percentage of acquisition of long-term protective levels. The anti-PRP geometric mean titers were 9.9, 8.3 and 5.14 micro g/mL, respectively (P < 0.05). CONCLUSIONS: The use of aluminum compounds adjuvants in Hib-CRM197 conjugate vaccines does not impact the safety profile, while it does increase the magnitude of anti-PRP antibody titers.  相似文献   
    7.
    The association between Tuberous Sclerosis (TS) and Angiomyolipoma (AML) is well known. A patient with TS and giant AML mimicking Renal Cell Carcinoma (RCC), measuring 29 × 18 × 11 cm, weighing 4700 gr is presented. Imaging studies revealed coexistent pulmonary lymphangioleiomyomatosis and concurrent renal and pulmonary involvement is extremely rare in patients in TS. We believe that the growth potential of this hamartomatous lesion may reach to a life threatening size. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
    8.
    In the present study, attempts have been made to determine the effects of honey on intestinal morphology, postoperative adhesions, and the healing of colonic anastomoses in the rats after colonic resection and anastomosis. Thirty-six rats were randomly divided into three groups each including 12 animals. Colonic resection and anastomosis were performed on all animals. Rats were fed with standard rat chow in group I, standard rat chow plus 10 g/kg/day honey in group II and artificial honey including the same caloric amount with honey in group III. Adhesion scores, bursting pressures and histopathological examinations were evaluated. Colonic bursting pressures of honey group were significantly better than control and artificial honey groups. Histological analysis of anastomotic site showed that submucosa and muscularis propria were nearly filled with granulation tissue and regular fibrin matrix in honey group. There was statistically significant difference between the adhesion scores of honey vs artificial honey and control groups. The scores of histological changes of ileum in honey group were significantly different from other groups. These results indicate a protective role of honey against intraabdominal adhesions and anastomotic dehiscence.  相似文献   
    9.
    The usefulness of preoperative radionuclide scanning of the parathyroid glands in patients with primary or secondary hyperparathyroidism was long controversial because available techniques were of limited diagnostic efficacy. Technetium-99m-labeled sestamibi (99Tc-sestamibi) is a new radiopharmaceutical agent easily detected by gamma cameras. The first parathyroid imaging studies done with 99Tc-sestamibi about 10 years ago used a double-phase technique to separate thyroid and parathyroid tissue. Although promising, this method was less than ideal, particularly in multiple gland primary hyperparathyroidism and in secondary hyperparathyroidism. For several years, we have been using subtraction between two images acquired simultaneously, one with 99Tc-sestamibi, which binds to thyroid and parathyroid tissue, and the other with 123-iodine, which binds only to thyroid tissue. The remarkable efficacy of this technique in both primary and secondary hyperparathyroidism invites a reappraisal of the place of radionuclide imaging as a preoperative localization procedure done to reduce the need for repeat surgery. The usefulness of this technique in selecting candidates for unilateral surgery among patients with primary hyperparathyroidism is discussed.  相似文献   
    10.
    PURPOSEWe aimed to evaluate the prostate volumes calculated as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines, intraobserver and interobserver variability, and the agreement between the two measurement methods.METHODSProstate mpMRI examinations of 114 patients were evaluated retrospectively. T2-weighted sequences in the axial and sagittal planes were used for the measurement of the prostate volume. The measurements were performed by two independent observers as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines. Both observers conducted the measurements twice and the average values were obtained. In order to prevent bias, the observers carried out measurements at one-week intervals. In order to assess intraobserver variability, observers repeated the measurements again at one-week intervals. The prostate volume was calculated using the ellipsoid formula (W×H×L×0.52).RESULTSIntraclass correlation coefficient (ICC) revealed almost perfect agreement between the first and second observers for the measurements according to both PI-RADS v2 (0.93) and PI-RADS v2.1 (0.96) guidelines. The measurements were repeated by both observers. According to the ICC values, there was excellent agreement between the first and second measurements with respect to both PI-RADS v2 and PI-RADS v2.1 for first (0.94 and 0.96, respectively) and second observer (0.94 and 0.97, respectively). For both observers, the differences had a random, homogeneous distribution, and there was no clear relationship between the differences and mean values.CONCLUSIONThe ellipsoid formula is a reliable method for rapid assessment of prostate volume, with excellent intra- and interobserver agreement and no need for expert training. For the height measurement, the recommendations of the PIRADS v2.1 guideline seem to provide more consistently reproducible results.

    The prostate gland is one of the organs for which the disease incidence and prevalence in men increases with age. Prostate volume (PV) has an important role in the evaluation and management of both malignant and benign prostate diseases (13). In benign prostatic hyperplasia (BPH), prostate volume is used to decide upon treatment and evaluate response to medical therapy (35). In the diagnosis of prostate cancer, one of the important markers is prostate-specific antigen (PSA), but it has low specificity, and therefore PSA derivatives are used to increase its specificity. One example is PSA density, which is obtained by dividing the PSA value by PV. In the treatment of prostate cancer, PV is important, and the effectiveness of brachytherapy decreases in prostates with a volume greater than 50 mL (6). Furthermore, PV is used to identify appropriate patients for brachytherapy and select the number of radioactive seeds, and also determine fractionation for external beam radiation, radical prostatectomy operating planning and continence rate counseling, and focal therapy candidacy preparation (7, 8). For these reasons, it is vital to accurately calculate PV.There are many methods that can be used to calculate PV, with the ellipsoid formula being one of the most preferred since it is easy to apply and highly time-efficient (14, 9). Many studies have shown that this method has high accuracy due to the elliptic shape of the prostate (1, 2, 1013). The ellipsoid formula is obtained by multiplying the height (anterior-posterior), width (medio-lateral) and length (cranio-caudal) values of the prostate by 0.52. These measurements can be performed by transrectal ultrasonography (TRUS) or magnetic resonance imaging (MRI). TRUS has certain disadvantages, such as being operator-dependent and susceptible to sonographic artifacts (14). MRI, which has become increasingly popular in recent years, allows for an accurate definition of the prostate boundaries and multiplanar measurements through its high contrast resolution of soft tissues (1, 5). It also provides more accurate measurements than TRUS (4, 15, 16).In order to ensure global standardization in the reporting of prostate MRI findings, PI-RADS v2 published in 2015, which is the revised version of PI-RADS 1.0, and the last updated version PI-RADS v2.1 made available in 2019, propose different calculation methods for the measurement of height in obtaining PV (17, 18). The midaxial plane is recommended for this measurement in PI-RADS v2, while the midsagittal plane is recommended in PI-RADS v2.1. This study aimed to evaluate the interobserver and intraobserver variability of PV calculated by both measurement methods and the agreement between the two measurement methods.  相似文献   
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