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91.
In spontaneous cycles both LH and FSH are secreted in a surge at midcycle. In in vitro fertilization (IVF) cycles, hCG administration results in elevation of LH-like activity only. The objective of this study was to compare the effectiveness of a single midcycle dose of GnRH agonist with hCG on follicular maturation. Eighteen IVF cycles in 14 women were randomized to receive either 0.5 mg leuprolide acetate or 5000 IU hCG at midcycle. Both groups underwent identical ovarian stimulation and cycle monitoring. On the day of GnRH agonist or hCG administration, estradiol concentrations and the number of follicles 1.5 cm or larger were the same in both groups. Mean serum LH and FSH levels were elevated for 34 h after GnRH agonist administration. In contrast, mean serum hCG levels were elevated for approximately 6 days after the administration of hCG, and serum FSH levels did not change. Mean luteal phase serum estradiol concentrations were lower in the GnRH agonist group than in the hCG group (P less than 0.02). No differences were observed in mean serum progesterone or PRL during the luteal phase or in the length of the luteal phase in the two groups. The mean number of oocytes retrieved and embryo number and quality did not differ between the two groups. Three of nine GnRH agonist cycles and none of nine hCG cycles resulted in clinical pregnancy (P = 0.1). The results of this study indicate that GnRH agonist is able to simulate a midcycle surge of gonadotropins, leading to follicular maturation and pregnancy. Further work is needed to determine whether there is any clinical advantage of GnRH agonist over hCG administration with regard to pregnancy rates.  相似文献   
92.
Herpes simplex virus (HSV) causes life-threatening infections in immunocompromised patients such as transplant recipients and patients with hematologic malignancies. We herein describe the case of a patient with chronic myeloid leukemia blastic transformation who developed severe herpetic tonsillitis complicated by tonsillar abscess formation. Abscess formation was determined by computed tomography, whereas tonsillitis due to HSV was confirmed by pathologic and immunohistochemical examinations of the tonsillar biopsy. For molecular confirmation, HSV DNA was amplified by LightCycler PCR and type (HSV-1) determined by melting point analysis. The patient responded promptly to antiviral treatment and there were no signs of recurrent infection at the follow-up. To our knowledge, this case is unique for being the first case of tonsillar abscess formation due to HSV-1, also emphasizing the importance of herpetic infections in the differential diagnosis of oropharyngeal small-sized lesions in the immunocompromised patient population.  相似文献   
93.

Background

Epidemiologic studies have reported a positive correlation between body mass index (BMI) and pancreatic cancer risk, but clinical relevance of obesity and/or body fat distribution on tumor characteristics and cancer-related outcome remain controversial. We sought to assess the influence of obesity and body fat distribution on pathologic characteristics and survival after pancreaticoduodenectomy for pancreatic adenocarcinoma.

Methods

Demographic and biometric data were collected on 328 patients undergoing pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. In a subset of patients, pancreatic fatty infiltration and fibrosis were assessed pathologically, and visceral fat area (VFA) was evaluated. Influence of BMI and body fat distribution on tumor characteristics and survival were evaluated.

Results

A significant positive correlation between BMI and VFA was observed, with a wide range of VFA value within each BMI class. According to BMI or VFA distribution, there were no significant differences in patient characteristics, intraoperative or perioperative outcome, or pathologic characteristics, with the exception of significantly higher blood loss in patients with an increased body weight or VFA. Unadjusted overall and disease-free survival between BMI class and VFA quartile were not significantly different.

Conclusions

In this study, obesity and body fat distribution were not correlated with specific tumor characteristics or cancer-related outcome.  相似文献   
94.

Background

Patients with locally unresectable pancreatic cancer (AJCC stage III) have a median survival of 10?C14?months. The objective of this study was to evaluate outcome of initially unresectable patients who respond to multimodality therapy and undergo resection.

Methods

Using a prospectively collected database, patients were identified who were initially unresectable because of vascular invasion and had sufficient response to nonoperative treatment to undergo resection. Overall survival (OS) was compared with a matched group of patients who were initially resectable. Case matching was performed using a previously validated pancreatic cancer nomogram.

Results

A total of 36 patients with initial stage III disease were identified who underwent resection after treatment with either systemic therapy or chemoradiation. Initial unresectability was determined by operative exploration (n?=?15, 42%) or by cross-sectional imaging (n?=?21, 58%). Resection consisted of pancreaticoduodenectomy (n?=?31, 86%), distal pancreatectomy (n?=?4, 11%), and total pancreatectomy (n?=?1, 3%). Pathology revealed T3 lesions in 26 patients (73%), node positivity in 6 patients (16%), and a negative margin in 30 patients (83%). The median OS in this series was 25?months from resection and 30?months since treatment initiation. There was no difference in OS from time of resection between the initial stage III patients and those who presented with resectable disease (P?=?.35).

Conclusions

In this study, patients who were able to undergo resection following treatment of initial stage III pancreatic cancer experienced survival similar to those who were initially resectable. Resection is indicated in this highly select group of patients.  相似文献   
95.

Background  

Positive peritoneal cytology confers the same prognosis as clinical stage IV disease in gastric cancer. Conventional cytology examination, however, has low sensitivity. We hypothesize that real-time polymerase chain reaction (RT-PCR) may have increased sensitivity and provide more accurate staging information.  相似文献   
96.
Journal of Assisted Reproduction and Genetics - To evaluates the effect of different modes of final follicular maturation triggering on the degree of apoptosis of granulosa cells (GCs) and the...  相似文献   
97.
Overexpression of antiapoptotic members of the Bcl-2 family are observed in approximately 80% of B-cell lymphomas, contributing to intrinsic and acquired drug resistance. Nullifying antiapoptotic function can potentially overcome this in-trinsic and acquired drug resistance. AT-101 is a BH3 mimetic known to be a potent inhibitor of antiapoptotic Bcl-2 family members including Bcl-2, Bcl-XL, and Mcl-1. In vitro, AT-101 exhibits concentration- and time-dependent cytotoxicity against lymphoma and multiple myeloma cell lines, enhancing the activity of cytotoxic agents. The IC50 for AT-101 is between 1 and 10 µM for a diverse panel of B-cell lymphomas. AT-101 was synergistic with carfilzomib (C), etoposide (E), doxorubicin (D), and 4-hydroxycyclophosphamide (4-HC) in mantle cell lymphoma (MCL) lines. In a transformed large B-cell lymphoma line (RL), AT-101 was synergistic when sequentially combined with 4-HC, but not when both drugs were added simultaneously. AT-101 also induced potent mitochondrial membrane depolarization (m) and apoptosis when combined with carfilzomib, but not with bortezomib in MCL. In severe combined immunodeficient (SCID) beige mouse models of drug-resistant B-cell lymphoma, 35 mg/kg per day of AT-101 was safe and efficacious. The addition of AT-101 to cyclophosphamide (Cy) and rituximab (R) in a schedule-dependent manner enhanced the efficacy of the conventional therapy.   相似文献   
98.
Metastatic prostate cancer may respond initially to hormone suppression, with involution of tumor sites, but ultimate tumor progression is inevitable. Our aim was to detect the proportion of bone and soft-tissue lesions that represent metabolically active tumor sites in patients with progressive metastatic prostate cancer. METHODS: In a prospective study, we compared 18F-FDG and L-methyl-11C-methionine (11C-methionine) PET with conventional imaging modalities (CIM), which included the combination of 99mTc-methylene diphosphonate scintigraphy, CT, or MRI. Twelve patients with prostate cancer, increasing levels of prostate-specific antigen (PSA), and at least 1 site (index lesion) with new or increasing disease on CIM were studied. The total numbers of soft-tissue and bone-tissue lesions, in a site-by-site comparison, were calculated for all imaging modalities. RESULTS: The sensitivities of 18F-FDG PET and 11C-methionine PET were 48% (167/348 lesions) and 72.1% (251/348 lesions), respectively, with CIM being used as the 100% reference (348/348). 11C-Methionine PET identified significantly more lesions than 18F-FDG PET (P < 0.01). All 12 patients with progressive metastatic prostate cancer had at least 1 lesion site of active metabolism for 18F-FDG or 11C-methionine, which could be used as an index lesion to monitor the metabolic response to therapy. A significant proportion of lesions (26%) had no detectable metabolism of 18F-FDG or 11C-methionine. Although technical factors cannot be totally excluded, we believe that metabolically inactive sites may be necrotic or dormant. More than 95% (251/258) of metabolically active sites (72% of the total number of lesions detected by CIM) metabolize 11C-methionine. 18F-FDG uptake is more variable, with 65% of metabolically active sites (48% of the total number of lesions detected by CIM). CONCLUSION: These findings reflect the different biologic characteristics of the lesions in a heterogeneous tumor such as prostate cancer and suggest that a time-dependent metabolic cascade may occur in advanced prostate cancer, with initial uptake of 11C-methionine in dormant sites followed by increased uptake of 18F-FDG during progression of disease.  相似文献   
99.
Reproducibility of 3D proton spectroscopy in the human brain.   总被引:2,自引:0,他引:2  
The inter- and intrasubject reproducibility of the metabolite levels of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho), obtained with three-dimensional (3D) multivoxel proton spectroscopy (1H-MRS), was analyzed in eight healthy volunteers. Serial, back-to-back measurements on a phantom showed the methodology and instrumentation to be highly reproducible, with a median coefficient of variation (CV) of 3.8%. In the human brain, the metabolite levels' variability was larger, with intrasubject median CVs for a total of 1876 signal voxels of 13.8%, 18.5%, and 20.1% for NAA, Cr, and Cho, respectively. These variations possibly arise from small, unavoidable, +/-1-2 mm volume-of-interest (VOI) repositioning uncertainties, which vary each 0.75-cm(3) voxel's partial fluid/gray/white-matter fractions. Comparing the CVs between eight subjects in a total of 324 selected voxels gave total interindividual CVs of 15.6%, 23.3%, and 24.4%, compared with intraindividual CVs in the same voxels of 14.4%, 14.8%, and 15.3%, for NAA, Cr, and Cho, respectively. Replacing the signal(s) from each voxel by the average of itself with its six canonical neighbors reduces the intrasubject median CVs to 8.3%, 9.5%, and 9.7%. The measurement uncertainties can be reduced at a cost of either spatial resolution (by using larger voxels) or time (by performing serial follow-ups).  相似文献   
100.
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