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101.

Purpose

This study aimed to evaluate the predictive and prognostic value of FDG PET/CT-based volumetric parameters in patients with oral tongue squamous cell carcinoma (OTSCC) treated by superselective intra-arterial chemoradiotherapy (IA-CRT).

Methods

We conducted a retrospective study including 33 patients with biopsy-proven OTSCC between May 2007 and February 2016. All of the patients were treated by IA-CRT. Pretreatment SUVmax and metabolic tumor volume (MTV) of the primary tumor were measured. The SUV thresholds of 2.5 and 5.0 were used. Progression-free survival (PFS) and overall survival (OS) were chosen as endpoints to evaluate prognosis. Univariate and multivariate analyses were performed to assess the potential independent effect of FDG PET/CT parameters.

Results

The median follow-up for surviving patients was 40.7 months (range 6.0–107.5 months). In univariate and multivariate analyses, SUVmax and MTV (5.0) were independent prognostic factors for PFS. In univariate analysis, SUVmax failed to predict OS. MTV (5.0) was a significant prognostic factor for OS, but multivariate analysis failed to show statistical independence because it could not exclude the possibility of an artifact due to N stage.

Conclusions

FDG PET/CT-based volumetric parameters may be significant prognostic markers for survival of patients with OTSCC who are treated by IA-CRT.
  相似文献   
102.
Cholangiocarcinoma (CCA) is a highly aggressive and metastatic type of malignant carcinoma that is associated with high mortality rates and is difficult to detect at early stages. Core 3 structure is a mucin-type O-glycans synthesized by β1,3-N-acetylglucosaminyltransferase 6 (core 3 synthase), which plays an important role in the digestive system, in particular gastrointestinal goblet cells. It has been reported that core 3 synthase-expressing cells show lower migratory and invasive rates, and lower metastatic activity. A immunohistochemical study also showed that this enzyme was expressed in normal epithelial cells of the colon, but completely disappeared in colorectal cancer cells. The present study aimed to identify biomarkers that could be used to predict the prognosis of patients with CCA. Pathological specimens of 185 CCA tissues were immunohistochemically stained with two antibodies, G8-144 and MECA-79, which recognize core 3 synthase and 6-sulfated N-acetyllactosamine on the extended core-1 O-glycans, respectively. The association between G8-144 or MECA-79 positivity and patient prognosis was statistically analyzed. Positive expression of G8-144 was associated with improved prognosis in patients with distal CCA (dCCA). Patients with dCCA positive for G8-144 showed lower mortality rates than those with negative expression. However, the positive expression of MECA-79 was associated with CCA progression and metastasis, indicating that it is a poor prognostic marker for CCA. In conclusion, as both antibodies resulted in mirror-image staining, the involvement of G8-144 and MECA-79 in O-glycan synthesis could be considered as potential favorable and unfavorable biomarkers, respectively, for CCA prognosis.  相似文献   
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Ectopic cervical thymoma is an extremely rare tumor thought to arise from ectopic thymic tissue caused by the aberrant migration of the embryonic thymus. We present the case of a 44-year-old woman with an ectopic cervical thymoma located in the carotid triangle. A computed tomography (CT) scan detected a mass in her right carotid triangle. On an unenhanced scan, the tumor showed homogeneous isodensity compared with muscles, and neither fat nor calcification was detected. A contrast-enhanced CT image obtained during the arterial phase showed intratumoral septa, while an image obtained during the parenchymal phase showed cystic changes within the mass. The patient underwent a surgical resection. A histological study enabled a diagnosis of type AB thymoma in which foci with the features of type A thymoma are admixed with foci rich in lymphocytes. This subtype is a benign tumor with a good prognosis. Ectopic cervical thymoma should be included in the differential diagnosis of solid masses located in the carotid triangle when the CT findings are typical of a thymoma.  相似文献   
107.
We report a case of body stalk anomaly detected prenatally by fetal magnetic resonance imaging (MRI) at 14 weeks’ gestation. A 29-year-old woman was followed during her first pregnancy. At 11–12 weeks’ gestation, our sonographic images showed multiple fetal deformities. An abdominal wall defect was suspected. The exteriorized abdominal contents and the lower limb appeared within the extraembryonic celom with an intact amniotic membrane. Fetal MRI at 14 weeks’ gestation confirmed a large anterior wall defect with herniation of the liver and bowel. In addition, abnormally rotated lower limb and scoliosis could be demonstrated. The fetus was prenatally diagnosed with body stalk anomaly, expected to be lethal in nature. The parents decided to terminate the pregnancy at 15 weeks’ gestation. Prenatal diagnosis of body stalk anomaly is usually based on sonographic findings. As far as we are aware, this is the first case report of body stalk anomaly satisfactorily diagnosed by fetal MRI in the early second trimester. Fetal MRI scans should provide ground for a precise antenatal diagnosis of body stalk anomaly from early gestation.  相似文献   
108.
BACKGROUND: Porphyromonas gingivalis is found in subgingival biofilm and is associated with periodontal disease. Bacteria in biofilms are able to resist higher antimicrobial concentrations than in suspension. Little is known about the susceptibility of P. gingivalis in biofilms to antimicrobial agents. The effects of chlorhexidine gluconate, minocycline hydrochloride, and metronidazole on P. gingivalis biofilms were examined in vitro. METHODS: P. gingivalis strain 381 biofilms were prepared on 32 hydroxyapatite disks. At 0, 24, 72, and 144 hours after perfusion of the three antimicrobial agents, two disks from each device were used to assess the antimicrobial effects by adenosine triphosphate (ATP) bioluminescence, and for morphological investigation by scanning electron microscopy (SEM). RESULTS: Close relationships were found between the results of the ATP analyses and the SEM observations in all groups examined. A significant decrease (P < 0.001) in ATP content was found between the chlorhexidine-treated and control groups. The extracellular matrix structure and P. gingivalis cells were altered in the presence of chlorhexidine. Minocycline hydrochloride also caused a decrease (P < 0.05) in the ATP content and morphological change on P. gingivalis biofilms. Metronidazole showed no significant efficacy against P. gingivalis biofilms. CONCLUSION: Chlorhexidine gluconate was effective at reducing the viability of P. gingivalis 381 cells in biofilms, while minocycline hydrochloride and metronidazole exhibited weaker effects.  相似文献   
109.
Epidermal basal cell damage in lichenoid tissue reactions (LTR) is considered to be the result of immunologic injury. In this study, we propose that LTR may be caused by local activation of Ia-reactive T cells. We have established allo-Iak-reactive helper T-cell clones and examined their behavior after adoptive transfer. We show that local transfer of 3 allo-Iak-reactive helper T-cell clones with different cross-reactivities and functions in vitro can cause delayed type hypersensitivity (DTH) reactions in vivo with antigen specificities identical to those demonstrated in vitro. Clone SK.1, when injected into appropriate recipients, caused massive dermal infiltrates of neutrophils and mononuclear cells. The latter were attracted to the epidermis and induced LTR-like basal cell degeneration which peaked at 72 h. Appropriate recipients were those strains of mice whose spleen cells were able to stimulate SK.1 cells to proliferate in vitro. Two other clones, SK.2.18 and SK.2.16, evoked significant DTH responses in their appropriate recipients, but the massive cellular infiltrates induced by either clone never invaded the epidermis or produced an LTR. The degeneration of epidermal cells caused by SK.1 cells did not correlate with the tested functions of this clone in vitro. The finding that only 1 of the 3 allo-Ia-reactive helper T-cell clones induced epidermotropic cellular infiltrates indicates that the infiltrative pattern of leukocytes in skin may depend on the particular T-cell clone that is activated.  相似文献   
110.
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