全文获取类型
收费全文 | 55512篇 |
免费 | 4959篇 |
国内免费 | 3268篇 |
专业分类
耳鼻咽喉 | 856篇 |
儿科学 | 692篇 |
妇产科学 | 618篇 |
基础医学 | 7464篇 |
口腔科学 | 1068篇 |
临床医学 | 6696篇 |
内科学 | 9256篇 |
皮肤病学 | 814篇 |
神经病学 | 3307篇 |
特种医学 | 2731篇 |
外国民族医学 | 21篇 |
外科学 | 6044篇 |
综合类 | 6280篇 |
现状与发展 | 13篇 |
一般理论 | 5篇 |
预防医学 | 3213篇 |
眼科学 | 1304篇 |
药学 | 5726篇 |
38篇 | |
中国医学 | 2443篇 |
肿瘤学 | 5150篇 |
出版年
2024年 | 173篇 |
2023年 | 872篇 |
2022年 | 2152篇 |
2021年 | 3031篇 |
2020年 | 2190篇 |
2019年 | 2020篇 |
2018年 | 2053篇 |
2017年 | 1838篇 |
2016年 | 1839篇 |
2015年 | 2663篇 |
2014年 | 3084篇 |
2013年 | 2992篇 |
2012年 | 4288篇 |
2011年 | 4541篇 |
2010年 | 2809篇 |
2009年 | 2239篇 |
2008年 | 2970篇 |
2007年 | 2988篇 |
2006年 | 2711篇 |
2005年 | 2565篇 |
2004年 | 1880篇 |
2003年 | 1719篇 |
2002年 | 1435篇 |
2001年 | 1147篇 |
2000年 | 1139篇 |
1999年 | 1151篇 |
1998年 | 638篇 |
1997年 | 622篇 |
1996年 | 487篇 |
1995年 | 437篇 |
1994年 | 390篇 |
1993年 | 228篇 |
1992年 | 377篇 |
1991年 | 298篇 |
1990年 | 297篇 |
1989年 | 262篇 |
1988年 | 237篇 |
1987年 | 193篇 |
1986年 | 161篇 |
1985年 | 122篇 |
1984年 | 81篇 |
1983年 | 68篇 |
1982年 | 27篇 |
1981年 | 35篇 |
1980年 | 22篇 |
1979年 | 37篇 |
1978年 | 21篇 |
1977年 | 22篇 |
1976年 | 32篇 |
1974年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Bing-Quan Yang Yang Lu Jia-Jia He Tong-Zhi Wu Zuo-Ling Xie Cheng-Hao Lei Yi Zhou Jing Han Mei-Qi Bian Hong You De-Xian Mei Zi-Lin Sun 《中华医学杂志(英文版)》2015,128(24):3270-3275
Background:
The conventional approaches to diabetes screening are potentially limited by poor compliance and laboratory demand. This study aimed to evaluate the performance of fasting plasma glucose (FPG) and postprandial urine glucose (PUG) in screening for diabetes in Chinese high-risk population.Methods:
Nine hundred and nine subjects with high-risk factors of diabetes underwent oral glucose tolerance test after an overnight fast. FPG, hemoglobin A1c, 2-h plasma glucose (2 h-PG), and 2 h-PUG were evaluated. Diabetes and prediabetes were defined by the American Diabetes Association criteria. The area under the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic accuracy of 2 h-PUG, and the optimal cut-off determined to provide the largest Youden index. Spearman correlation was used for relationship analysis.Results:
Among 909 subjects, 33.4% (304/909) of subjects had prediabetes, and 17.2% (156/909) had diabetes. The 2 h-PUG was positively related to FPG and 2 h-PG (r = 0.428 and 0.551, respectively, both P < 0.001). For estimation of 2 h-PG ≥ 7.8 mmol/L and 2 h-PG ≥ 11.1 mmol/L using 2 h-PUG, the area under the ROC curve were 0.772 (95% confidence interval [CI ]: 0.738–0.806) and 0.885 (95% CI: 0.850–0.921), respectively. The corresponding optimal cut-offs for 2 h-PUG were 5.6 mmol/L and 7.5 mmol/L, respectively. Compared with FPG alone, FPG combined with 2 h-PUG had a higher sensitivity for detecting glucose abnormalities (84.1% vs. 73.7%, P < 0.001) and diabetes (82.7% vs. 48.1%, P < 0.001).Conclusion:
FPG combined with 2 h-PUG substantially improves the sensitivity in detecting prediabetes and diabetes relative to FPG alone, and may represent an efficient layperson-oriented diabetes screening method. 相似文献993.
Xuan Qiu De-Hu Tian Chang-Ling Han Wei Chen Zhan-Jian Wang Zhen-Yun Mu Kuan-Zhi Liu 《中华医学杂志(英文版)》2015,128(24):3283-3291
Background:
Plantar pressure serves as a key factor for predicting ulceration in the feet of diabetes patients. We designed this study to analyze plantar pressure changes and correlating risk factors in Chinese patients with type 2 diabetes.Methods:
We recruited 65 patients with type 2 diabetes. They were invited to participate in the second wave 2 years later. The patients completed identical examinations at the baseline point and 2 years later. We obtained maximum force, maximum pressure, impulse, pressure-time integral, and loading rate values from 10 foot regions. We collected data on six history-based variables, six anthropometric variables, and four metabolic variables of the patients.Results:
Over the course of the study, significant plantar pressure increases in some forefoot portions were identified (P < 0.05), especially in the second to forth metatarsal heads. Decreases in heel impulse and pressure-time integral levels were also found (P < 0.05). Plantar pressure parameters increased with body mass index (BMI) levels. Hemoglobin A1c (HbA1c) changes were positively correlated with maximum force (β = 0.364, P = 0.001) and maximum pressure (β = 0.366, P = 0.002) changes in the first metatarsal head. Cholesterol changes were positively correlated with impulse changes in the lateral portion of the heel (β = 0.179, P = 0.072) and pressure-time integral changes in the second metatarsal head (β = 0.236, P = 0.020). Ankle-brachial index (ABI) changes were positively correlated with maximum force changes in the first metatarsal head (β = 0.137, P = 0.048). Neuropathy symptom score (NSS) and common peroneal nerve sensory nerve conduction velocity (SCV) changes were positively correlated with some plantar pressure changes. In addition, plantar pressure changes had a correlation with the appearance of infections, blisters (β = 0.244, P = 0.014), and calluses over the course of the study.Conclusions:
We should pay attention to the BMI, HbA1c, cholesterol, ABI, SCV, and NSS changes in the process of preventing high plantar pressure and ulceration. Some associated precautions may be taken with the appearance of infections, blisters, and calluses. 相似文献994.
Background:
Preeclampsia is a multifactorial disease during pregnancy. Dysregulated lipid metabolism may be related to some preeclampsia. We investigated the relationship between triglycerides (TGs) and liver injury in different preeclampsia-like mouse models and their potential common pathways.Methods:
Preeclampsia-like models (Nw-nitro-L-arginine-methyl ester [L-NAME], lipopolysaccharide [LPS], apolipoprotein C-III [Apo] transgnic mice + L-NAME, β2 glycoprotein I [βGPI]) were used in four experimental groups: L-NAME (LN), LPS, Apo-LN and βGPI, respectively, and controls received saline (LN-C, LPS-C, Apo-C, βGPI-C). The first three models were established in preimplantation (PI), early-, mid- and late-gestation (EG, MG and LG). βGPI and controls were injected before implantation. Mean arterial pressure (MAP), 24-hour urine protein, placental and fetal weight, serum TGs, total cholesterol (TC) and pathologic liver and trophocyte changes were assessed.Results:
MAP and proteinuria were significantly increased in the experimental groups. Placenta and fetal weight in PI, EP and MP subgroups were significantly lower than LP. Serum TGs significantly increased in most groups but controls. TC was not different between experimental and control groups. Spotty hepatic cell necrosis was observed in PI, EG, MG in LN, Apo-LN and βGPI, but no morphologic changes were observed in the LPS group. Similar trophoblastic mitochondrial damage was observed in every experimental group.Conclusions:
Earlier preeclampsia onset causes a higher MAP and urine protein level, and more severe placental and fetal damage. Preeclampsia-like models generated by varied means lead to different changes in lipid metabolism and associated with liver injury. Trophoblastic mitochondrial damage may be the common terminal pathway in different preeclampsia-like models. 相似文献995.
Jian Zhang Yi Li Gui-Zhou Tao Yun-Dai Chen Tao-Hong Hu Xue-Bin Cao Quan-Min Jing Xiao-Zeng Wang Ying-Yan Ma Geng Wang Hai-Wei Liu Bin Wang Kai Xu Jing Li Jie Deng Ya-Ling Han 《中华医学杂志(英文版)》2015,128(6):784-789
Background:
Current randomized trials have demonstrated the effects of short-term rosuvastatin therapy in preventing contrast-induced acute kidney injury (CIAKI). However, the consistency of these effects on patients administered different volumes of contrast media is unknown.Methods:
In the TRACK-D trial, 2998 patients with type 2 diabetes and concomitant chronic kidney disease (CKD) who underwent coronary/peripheral arterial angiography with or without percutaneous intervention were randomized to short-term (2 days before and 3 days after procedure) rosuvastatin therapy or standard-of-care. This prespecified analysis compared the effects of rosuvastatin versus standard therapy in patients exposed to (moderate contrast volume [MCV], 200–300 ml, n = 712) or (high contrast volume [HCV], ≥300 ml, n = 220). The primary outcome was the incidence of CIAKI. The secondary outcome was a composite of death, dialysis/hemofiltration or worsened heart failure at 30 days.Results:
Rosuvastatin treatment was associated with a significant reduction in CIAKI compared with the controls (2.1% vs. 4.4%, P = 0.050) in the overall cohort and in patients with MCV (1.7% vs. 4.5%, P = 0.029), whereas no benefit was observed in patients with HCV (3.4% vs. 3.9%, P = 0.834). The incidence of secondary outcomes was significantly lower in the rosuvastatin group compared with control group (2.7% vs. 5.3%, P = 0.049) in the overall cohort, but it was similar between the patients with MCV (2.0% vs. 4.2%, P = 0.081) or HCV (5.1% vs. 8.8%, P = 0.273).Conclusions:
Periprocedural short-term rosuvastatin treatment is effective in reducing CIAKI and adverse clinical events for patients with diabetes and CKD after their exposure to a moderate volume of contrast medium. 相似文献996.
Atypical depression has been linked to low hypothalamic-pituitary-adrenocortical axis activity and exhibits physical and affective symptoms resembling those of glucocorticoid deficiency. Because atypical depression has also been defined by preferential responsiveness to monoamine oxidase inhibitors (MAO-I), we hypothesized that MAO-I reverse these abnormalities by interfering with glucocorticoid feedback and increasing hypothalamic-pituitary-adrenocortical activity. To test this hypothesis, we measured plasma hormones and ACTH secretagogue gene expression in male C57BL/6 mice treated chronically with saline vehicle or phenelzine, a representative MAO-I. Changes in glucocorticoid feedback were evaluated using adrenalectomized (ADX) mice with and without corticosterone replacement. Antidepressant efficacy was confirmed by decreased immobility during forced swim testing. Phenelzine significantly increased circadian nadir and postrestraint plasma corticosterone levels in sham-operated mice, an effect that correlated with increased adrenocortical sensitivity to ACTH. Phenelzine increased circadian nadir, but not poststress ACTH in ADX mice, suggesting that phenelzine augmented corticosterone secretion in sham-operated mice by increasing stimulation and decreasing feedback inhibition of hypothalamic-pituitary activity. Consistent with the latter possibility, phenelzine significantly increased plasma ACTH and paraventricular hypothalamus CRH mRNA in ADX, corticosterone-replaced mice. Phenelzine did not increase paraventricular hypothalamus CRH or vasopressin mRNA in ADX mice lacking corticosterone replacement. We conclude that chronic phenelzine treatment induces sustained increases in glucocorticoids by impairing glucocorticoid feedback, increasing adrenocortical responsiveness to ACTH, and increasing glucocorticoid-independent stimulation of hypothalamic-pituitary activity. The resulting drive for adrenocortical activity could account for the ability of MAO-I to reverse endocrine and psychiatric symptoms of glucocorticoid deficiency in atypical depression. 相似文献
997.
Park YH Lee HC Song HG Jung S Ryu SH Shin JW Chung YH Lee YS Suh DJ 《Journal of gastroenterology and hepatology》2003,18(8):927-933
BACKGROUND AND AIM: Recently, antibiotic-resistant microorganisms have been increasingly noted in Korean patients with spontaneous bacterial peritonitis (SBP). The present study investigated the changing pattern of antibiotic resistance and its effects on the clinical outcome in treating SBP. METHODS: The present study retrospectively analyzed 87 episodes of SBP in 1995, 222 in 1998, and 271 in 1999. The isolated microorganisms and their antibiotic susceptibility were compared, and prognostic factors for survival were analyzed. RESULTS: Microorganisms were isolated in 41% of total episodes. The three most frequently isolated organisms were Escherichia coli (48%), Klebsiella pneumoniae (15%), and Aeromonas (8%). Strains that were resistant to cefotaxime in Gram-negative bacilli significantly increased from 7% in 1995 to 28% in 1999, and those to ciprofloxacin increased from 10% to 32%. Treatment failure also increased from 6% to 23%. Combined hepatocellular carcinoma and SBP caused by extended-spectrum beta-lactamase-producing strains were two independent prognostic factors for survival. CONCLUSION: Considering the increase in antibiotic-resistant microorganisms related to SBP, measures to prevent the in-hospital spread of resistant strains and the indiscriminate use of antibiotics should be instituted more stringently. 相似文献
998.
999.
Han W Ng YK Axelrod D Levitan ES 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(25):14577-14582
Neuropeptides are slowly released from a limited pool of secretory vesicles. Despite decades of research, the composition of this pool has remained unknown. Endocrine cell studies support the hypothesis that a population of docked vesicles supports the first minutes of hormone release. However, it has been proposed that mobile cytoplasmic vesicles dominate the releasable neuropeptide pool. Here, to determine the cellular basis of the releasable pool, single green fluorescent protein-labeled secretory vesicles were visualized in neuronal growth cones with the use of an inducible construct or total internal reflection fluorescence microscopy. We report that vesicle movement follows the diffusion equation. Furthermore, rapidly moving secretory vesicles are used more efficiently than stationary vesicles near the plasma membrane to support stimulated release. Thus, randomly moving cytoplasmic vesicles participate in the first minutes of neuropeptide release. Importantly, the preferential recruitment of diffusing cytoplasmic secretory vesicles contributes to the characteristic slow kinetics and limited extent of sustained neuropeptide release. 相似文献
1000.
Yanyang Chen Fen Wang Anjia Han 《International journal of clinical and experimental pathology》2015,8(7):8632-8635
Fat-forming solitary fibrous tumor (SFT) is a rare soft tissue tumor. Herein, we reported a 30-year-old woman was found to have a solid mass measuring 60×45 mm in the right kidney on an abdominal computed tomography scan. The tumor was well-circumscribed and composed of cellular nodules with the classic SFT admixed with clusters and lobules of mature adipocytes. Immunohistochemistry staining showed that the tumor cells were diffusely and strongly positive for CD34 and Bcl-2, focally and weakly positive for CD99 and EMA. Mature adipocytes were positive for S-100 protein. Ki-67 expression was found in approximately 2% of tumor cells. However, tumor cells were negative for cytokeratin, S-100 protein, HMB-45, Melan-A, SMA, and CD117. We made the pathological diagnosis of fat-forming SFT of the right kidney. The differential diagnosis includes angiomyolipoma, liposarcoma, spindle cell lipoma, sarcomatoid renal cell carcinoma, synovial sarcoma, and gastrointestinal stromal tumor. The patient was alive and well without evidence of recurrence or metastasis at 19 months after tumor resection. 相似文献