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941.
The purpose was to compare two-dimensional (2D) magnetic resonance pancreatography (MRP) with 3D MRP to evaluate intraductal papillary mucinous neoplasm (IPMN). Thirty-four patients (22 men, 12 women; age range, 45–80 years) with IPMN (n = 40) were examined with MRP on 2D and 3D sequences. Two readers independently reviewed the images to assess the overall image quality, artifacts, lesion location, communication with main pancreatic duct, and potential for malignancy. The readers assigned their confidence level (1–5) for predicting ductal communication of the lesion. The results of MRP were compared with endoscopic retrograde pancreatography and surgical and histopathologic findings. Studies obtained with 3D MRP were of significantly higher technical quality than those obtained with 2D MRP. Although 3D MRP showed higher area under the ROC curve (Az) values for predicting ductal communication of the lesion, there was no statistical significance between Az values of 2D and 3D MRP (Az for 2D = 0.821, 0.864 for readers 1 and 2, respectively, and Az for 3D= 0.964, 0.921). Accuracies for discriminating benign from malignant lesions were 70 and 67.5% (reader 1 and 2, respectively, for 2D) and 62.5 and 80.1% (3D). 3D MRP showed superior image quality to that of 2D MRP but did not increase the diagnostic accuracy for predicting ductal communication of the lesion.  相似文献   
942.
报道30例高原病患者红细胞免疫功能的研究结果,并与310例高原居住一年以上健康人比较,结果表明:高原病患者红细胞免疫粘附功能明显降低,红细胞免疫复合物花积率(RICA)显著升高17.68±7.36%,健康人10.83±3.07%(P<0.01),血清红细胞免疫调节因子促进率(RFER)明显降低13.26±10.48%,健康人45.01±19.08%(P<0.01);红细胞免疫调节因子抑制率(RFIR)显著升高60.68±21.36%,健康人19.09±10.07(P<0.01);RICA 增高与 RFIR 活性具有显著相关关系(P<0.005)。提示红细胞免疫功能参与了高原病病理发生发展过程。  相似文献   
943.

Purpose

Metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from 18F-FDG PET/CT are emerging prognostic biomarkers in human solid cancers; yet few studies have investigated their clinical and prognostic significance in oral cavity squamous cell carcinoma (OSCC). The present retrospective study evaluated the utility of pretreatment MTV and TLG measured by 18F-FDG PET/CT to predict survival and occult metastasis (OM) in OSCC.

Methods

Of 162 patients with OSCC evaluated preoperatively by 18F-FDG PET/CT, 105 who underwent definitive surgery with or without adjuvant therapy were eligible. Maximum standardized uptake value (SUVmax), MTV and TLG were measured. For calculation of MTV, 3-D regions of interest were drawn and a SUV threshold of 2.5 was used for defining regions. Univariate and multivariate analyses identified clinicopathological and imaging variables associated with OM, disease-free survival (DFS) and overall survival (OS).

Results

The median (range) SUVmax, MTV and TLG were 7.3 (0.7–41.9), 4.5 ml (0.7–115.1 ml) and 18.3 g (2.4–224.1 g), respectively. Of 53 patients with clinically negative lymph nodes, OM was detected in 19 (36 %). By univariate and multivariate analyses, MTV (P?=?0.018) and TLG (P?=?0.011) were both independent predictive factors for OM, although they were not independent of each other. The 4-year DFS and OS rates were 53.0 % and 62.0 %, respectively. Univariate and multivariate analyses revealed that MTV (P?=?0.001) and TLG (P?=?0.006), with different cut-off levels, were both independent predictive factors for DFS, although they were not independent of each other, and MTV (P?=?0.001), TLG (P?=?0.002) and the involved resection margin (P?=?0.007) were independent predictive factors for OS.

Conclusion

Pretreatment MTV and TLG may be useful in stratifying the likelihood of survival and predicting OM in OSCC.  相似文献   
944.

Purpose

To retrospectively evaluate the MR imaging features of early bile duct cancer and to correlate them with the clinicopathologic findings.

Materials and Methods

This retrospective study was approved by our institutional review board, and informed consent was waived. Seventeen patients with surgically proven early bile duct cancer who had undergone preoperative MR cholangiopancreatography with gadolinium‐enhanced MR imaging, were included in this study. Two, experienced radiologists evaluated the MR images in consensus regarding the following findings: tumor number and morphology; signal intensity of the tumor; sharpness of the outer border of the bile duct wall; enhancement pattern of the tumor; and the presence of enlarged peribiliary lymph nodes. Another radiologist measured the SNR of the tumor and bile duct wall on gadolinium‐enhanced MRI during the dynamic phases to evaluate the tumor enhancement degree.

Results

In all patients, MR imaging demonstrated single or multiple intraluminal bile duct masses showing a sharply defined outer margin. The most common enhancement pattern of the biliary lesions showed heterogeneous amorphous enhancement or heterogeneous enhancement with central, dot‐like structures or vascular structures (76.5%, 13/17 patients). The difference of SNR between bile duct and tumor was greatest in the equilibrium phase (P < 0.05).

Conclusion

MRCP combined with dynamic contrast‐enhanced MRI can be useful for detecting early bile duct cancers. Common MR findings of early bile duct cancer include one or more inhomogeneously enhancing intraductal masses with clear outer margins and preservation of the bile duct wall. J. Magn. Reson. Imaging 2008;28:1466–1475. © 2008 Wiley‐Liss, Inc.  相似文献   
945.
BackgroundPenile cancer is a relatively rare genital malignancy whose incidence and mortality are rising in many countries.ObjectiveThis study aims to assess the recent incidence and mortality patterns and incidence trends of penile cancer.MethodsThe age-standardized incidence and mortality rates (ASIR and ASMR, respectively) of penile cancer in 2020 were estimated from the Global Cancer Registries (GLOBOCAN) database. Incidence trends of penile cancer from 1973 to 2012 were assessed in 44 populations from 43 countries using the Cancer Incidence in Five Continents plus (CI5plus) and the Nordic Cancer Registries (NORDCAN) databases. Average annual percentage change was calculated to quantify trends in ASIR using joinpoint regression.ResultsGlobally, the estimated ASIR and ASMR of penile cancer were 0.80 (per 100,000) and 0.29 (per 100,000) in 2020, equating to 36,068 new cases and 13,211 deaths in 2020, respectively. There was no significant correlation between the ASIR (P=.05) or ASMR (P=.90) and Human Development Index. In addition, 15 countries saw increasing ASIR for penile cancer, 13 of which were from Europe (United Kingdom, Lithuania, Norway, Estonia, Finland, Sweden, Cyprus, Netherlands, Italy, Croatia, Slovakia, Russia, and the Czech), and 2 from Asia (China and Israel).ConclusionsAlthough the developing countries still bear the higher incidence and mortality of penile cancer, the incidence is on the rise in most European countries. To mitigate the disease burden resulting from penile cancer, measures to lower the risk for penile cancers, including improving penile hygiene and male human papillomavirus vaccination, may be warranted.  相似文献   
946.
“铁打的营盘流水的兵”,到哪儿都是这个理。可当“铁打的营盘”遭遇“流水的人才”结果会怎样?曾几何时,一度人才防线牢不可破的公立医院,在面临外资和民营医疗机构强大的“挖角”攻势下,不得不仓促应战。虽然目前公立医院在这场人才拔河较量中仍具优势,只是不知这种优势还能维持多久?  相似文献   
947.
目的观察高原环境对青藏铁路参建者健康的影响,为高原地区卫生保障工作提供科学依据。方法应用现况调查和前瞻性调查方法,对109429名建设人员职业危害情况和采取的预防措施进行分析。结果2001-2004年青藏铁路建设人员109429人中,共发生559例肺水肿;294例脑水肿。2002年参建人员工后血常规改变、心电图改变、血压改变、尿常规改变和肝功改变检出率均高于工中,差异有统计学意义(P<0.01);2003年参建人员工后检查指标除尿常规未见显著性变化外,血常规、心电图、血压、和肝功能改变检出率均高于工中,差异有统计学意义(P<0.01)。按月份的发病情况进行统计结果显示肺水肿和脑水肿的发病率均以4月份发病率最高,9月份末最低,4月份的发病率明显高于其他月份,差异有统计学意义(P<0.01)。结论青藏高原环境恶劣,存在多种职业有害因素,对建设人员的危害严重。研究制定切实可行的防治措施可以明显减轻职业危害,保障建设者的安全健康。  相似文献   
948.
A total of 2169 samples from 21 tribal populations from different regions of India were scanned for the Y-chromosome Alu polymorphism. This study reports, for the first time, high frequencies (8-65%) of Y Alu polymorphic (YAP) insertion in northeast Indian tribes. All seven Jarawa samples from the Andaman and Nicobar islands had the YAP insertion, in conformity with an earlier study of Andaman Islanders. One isolated case with haplotype E* was found in Dungri Bhill, a western Indian population, while YAP insertion in northeast India and Andaman tribes was found in association with haplotype D* (M168, M174). YAP insertion frequencies reported in the mainland Indian populations are negligible, according to previous studies. Genetic drift may be the causative factor for the variable frequency of the YAP insertion in the mainland populations, while the founder effect may have resulted in the highest incidence of haplotype D among the Andaman Islanders. The results of YAP insertion and the evidence of previous mtDNA studies indicate an early out of Africa migration to the Andaman and Nicobar Islands. The findings of YAP insertion in northeast Indian tribes are very significant for understanding the evolutionary history of the region.  相似文献   
949.
Decay-accelerating factor (DAF) has been reported to be a cellular receptor for several enteroviruses. Buffalo green monkey kidney (BGMK) cells expressing human DAF (BGMK-hDAF cells) showed increased susceptibility and sensitivity to several types of enteroviruses compared to wild-type BGMK cells. When 17 frozen positive clinical samples were tested, BGMK cells detected 8 and BGMK-hDAF cells detected 16. Since the CaCo-2 cell line has been documented to support the replication of most enteroviruses, CaCo-2 cells were mixed with BGMK-hDAF cells in order to increase the number of viruses detected. Thirty-four frozen clinical samples that previously had tested positive for enteroviruses were tested, and the following numbers were detected: 33 of 34 by CaCo-2/BGMK-hDAF cells, 29 of 34 by CaCo-2/BGMK cells, 28 of 34 by H292/RD (E-mix A) and A-549/BGMK (E-mix B) cells, and 26 of 34 by MRC-5 and pRhMK cells.  相似文献   
950.
Mice lacking Na(+)/H(+) exchanger 1 (NHE1) suffer from recurrent seizures and die early postnatally. Although the mechanisms for seizures are not well established, our previous electrophysiological work has shown that neuronal excitability and Na(+) current density are increased in hippocampal CA1 neurons of these mutant mice. However, it is unknown whether this increased density is related to altered expression or functional regulation of Na(+) channels. In this work, we asked three questions: is the increased excitability limited to CA1 neurons, is the increased Na(+) current density related to an increased Na(+) channel expression, and, if so, which Na(+) channel subtype(s) is upregulated? Using neurophysiological, autoradiographic, and immunoblotting techniques, we showed that both CA1 and cortical neurons have an increase in membrane excitability and Na(+) current density; Na(+) channel density is selectively upregulated in the hippocampus and cortex (P < 0.05); and Na(+) channel subtype I is significantly increased in the hippocampus and Na(+) channel subtype II is increased in the cortex. Our results demonstrate that mice lacking NHE1 upregulate their Na(+) channel expression in the hippocampal and cortical regions selectively; this leads to an increase in Na(+) current density and membrane excitability. We speculate that neuronal overexcitability due to Na(+) channel upregulation in the hippocampus and cortex forms the basis of epileptic seizures in NHE1 mutant mice.  相似文献   
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