全文获取类型
收费全文 | 3124篇 |
免费 | 182篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 33篇 |
妇产科学 | 102篇 |
基础医学 | 370篇 |
口腔科学 | 25篇 |
临床医学 | 338篇 |
内科学 | 664篇 |
皮肤病学 | 47篇 |
神经病学 | 216篇 |
特种医学 | 168篇 |
外科学 | 259篇 |
综合类 | 31篇 |
一般理论 | 1篇 |
预防医学 | 419篇 |
眼科学 | 69篇 |
药学 | 262篇 |
中国医学 | 1篇 |
肿瘤学 | 299篇 |
出版年
2022年 | 30篇 |
2021年 | 46篇 |
2020年 | 25篇 |
2019年 | 43篇 |
2018年 | 46篇 |
2017年 | 39篇 |
2016年 | 37篇 |
2015年 | 53篇 |
2014年 | 75篇 |
2013年 | 130篇 |
2012年 | 152篇 |
2011年 | 136篇 |
2010年 | 107篇 |
2009年 | 80篇 |
2008年 | 125篇 |
2007年 | 175篇 |
2006年 | 163篇 |
2005年 | 171篇 |
2004年 | 153篇 |
2003年 | 161篇 |
2002年 | 146篇 |
2001年 | 103篇 |
2000年 | 94篇 |
1999年 | 73篇 |
1998年 | 38篇 |
1997年 | 38篇 |
1996年 | 36篇 |
1995年 | 30篇 |
1994年 | 22篇 |
1993年 | 20篇 |
1992年 | 37篇 |
1991年 | 56篇 |
1990年 | 45篇 |
1989年 | 45篇 |
1988年 | 35篇 |
1987年 | 33篇 |
1986年 | 32篇 |
1985年 | 31篇 |
1984年 | 27篇 |
1983年 | 21篇 |
1981年 | 21篇 |
1980年 | 16篇 |
1979年 | 24篇 |
1978年 | 22篇 |
1975年 | 16篇 |
1974年 | 16篇 |
1973年 | 15篇 |
1972年 | 18篇 |
1932年 | 15篇 |
1931年 | 21篇 |
排序方式: 共有3310条查询结果,搜索用时 46 毫秒
1.
2.
3.
Kaposi's sarcoma. CT-radiographic correlation 总被引:1,自引:0,他引:1
The role of CT in the diagnosis of intrathoracic Kaposi's sarcoma (KS) was evaluated retrospectively in 24 patients, in the absence of coexistent opportunistic infections. In all cases the diagnosis of KS was initially established by histologic evaluation of extrathoracic disease: 15 patients had verified parenchymal KS and nine patients endobronchial KS. (Chest roentgenograms were analyzed separately for each group: in 14 patients serial films were available for review. The predominant radiographic findings was the presence of nonspecific, bilateral, perihilar infiltrates in 22 of 24 cases (92 percent). Corresponding CT scans documented the presence of abnormal hilar densities characteristically extending into the adjacent pulmonary parenchyma along distinctly perivascular and peribronchial pathways. Discrete, poorly marginated nodules were identified radiographically in ten cases (42 percent); these proved to be randomly distributed throughout the parenchyma on CT. Radiographic evidence of mediastinal adenopathy was distinctly unusual, seen in only two cases (8 percent). While CT typically demonstrated shotty adenopathy, significantly enlarged nodes (greater than 1 cm) were rarely identified. We concluded that CT is more specific than routine roentgenograms for identifying pulmonary KS. While not pathognomonic, peribronchial and perivascular disease is sufficiently characteristic to obviate more invasive diagnostic procedures, especially in patients with established KS. 相似文献
4.
Paul N Bennett Leo Breugelmans Anthony Meade Dee Parkhurst 《Journal of renal nutrition》2006,16(1):59-62
OBJECTIVE: To assess the reliability of a nurse-performed nutrition screening tool (NST) for hemodialysis (HD) patients to identify nutritionally at-risk patients. DESIGN: Tool reliability assessment. SETTING AND PARTICIPANTS: The setting was nine non-hospital private (n = 3) and public (n = 6) HD units in Australia (two rural and seven metropolitan). Participants were 112 HD patients. RESULTS: A total of 112 HD patients (male = 65, female = 47) from 9 non-hospital HD units in Australia (seven metropolitan and two rural) were screened with the NST and the outcome of dietitian referral compared with Standard Dietitians Assessment. The mean age of patients was 57.6 years. Overall, the NST showed a sensitivity of 0.84 (range, 0.71 to 0.94; P < .05) and a specificity of 0.9 (range, 0.82 to 0.98; P < .05). The NST was more sensitive (sensitivity, 0.93 [range, 0.87 to 0.99; P < .05]) and was more specific for men (specificity, 0.92 [range, 0.85 to 0.99; P < .05]). Specificity was very strong in metropolitan patients (specificity, 0.94 [range, 0.87 to 1.01; P < .05]). CONCLUSIONS: The tool was more sensitive and specific than the NST previously reported by the same investigators. The tool is particularly specific in that it screens those patients not requiring dietitian intervention. The use of this tool may benefit HD units that do not have on-site or regular dietetic support to prioritize patients needing dietitian intervention. 相似文献
5.
Benzene disposition and metabolism were examined as a function of age in male C57BL/6N mice aged 3 and 18 months. Mice received a single oral dose of either 10 or 200 mg/kg 14C-benzene (approximately 25 microCi/kg). Excretion of 14C-derived benzene radioactivity (RA) was monitored in urine, feces, and as exhaled 14CO2 from 0 to 72 hr, and as exhaled unmetabolized benzene from 0 to 6 hr. At 10 mg/kg 14C-benzene, urinary elimination was the major route of excretion in both 3- and 18-month mice. Urinary excretion of 14C-derived benzene RA was significantly decreased in 18- vs. 3-month mice at 4, 6, 24, and 48 hr, while fecal excretion was significantly increased at 72 hr. Elimination of 14C-benzene as 14CO2 and unmetabolized 14C-benzene was also increased in 18- vs. 3-month mice at this dose. Hydroquinone glucuronide (HQG), phenylsulfate (PS), and muconic acid (MUC) were the major urinary metabolites at 10 mg/kg 14C-benzene in both 3- and 18-month mice, representing approximately 40, 28, and 15% of an administered dose of 14C-benzene. Smaller amounts of phenyl glucuronide (4.0%), pre-phenyl mercapturic acid (1.2%), and catechol glucuronide (0.5%) were also detected. No significant differences were found with age in the percentage of an administered dose of benzene excreted as the various metabolites at 10 mg/kg. At 200 mg/kg 14C-benzene, the total percentage of 14C-derived benzene RA eliminated in urine within 72 hr was not significantly different with age, but elimination at early time points (4, 6, and 8 hr) was significantly decreased in 18- vs. 3-month mice.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
7.
Acute appendicitis: CT and US correlation in 100 patients 总被引:19,自引:1,他引:18
8.
Early experience with laparoscopic abdominoperineal resection 总被引:4,自引:0,他引:4
Background: Laparoscopic abdominoperineal resection (LAPR) has not been fully evaluated as a technique in the treatment of rectal and
anal cancer or inflammatory bowel disease. The purpose of our study was to evaluate the early experience with laparoscopic
abdominoperineal resection at Washington University Medical Center.
Methods: A prospective analysis was performed on the first 21 patients undergoing the procedure at Washington University Medical Center.
Indications for surgery included rectal cancer (14 patients), anal squamous cell cancer (four patients), inflammatory bowel
disease (two patients), and anal melanoma (one patient).
Results: The procedure was converted to open procedure in four patients (19%). The mean (±SEM) operative time and blood loss for completed
and converted LAPR were 239 ± 11 min and 424 ± 43 ml, respectively. Postoperative hematocrit dropped a mean of 8.3% ± 1.2%
SEM; five patients required blood transfusion (24%). Wound complication occurred in four patients (19%; three perineal, one
trocar site). Bowel function returned after a mean of 3 days, and mean postoperative hospital stay for the completed LAPR
group was 5 days. Mild pain was experienced by 81% of patients (17/21) while 19% (4/21) noted moderate pain, usually of the
perineal wound. The mean duration of patient-controlled analgesia use was 2 days. During the 1–44-month follow-up, six patients
(29%) died from cancer (stage III or IV at operation) and only one patient developed local recurrence in the pelvis (5%).
There were no trocar-site implants of cancer. Furthermore, there was no relationship between prior abdominal operations, the
amount of blood loss, postoperative drop of hematocrit, or blood transfusion requirement and the length of hospitalization
or complication rates.
Conclusion: Laparoscopic abdominoperineal resection is a feasible alternative to the conventional open technique in both cancer and colitis
patients.
Received: 23 April 1996/Accepted: 8 July 1996 相似文献
9.
10.
The undecapeptide, substance P, is known to be synthesized in cell bodies of dorsal root ganglia. This neuropeptide is also known to modulate sensory, nociceptive transmission postsynaptically on dorsal horn interneurons. In the animal model used in the current study, experimental mechanical stimulation of dorsal root ganglia and nerve roots increased the amounts of substance P, as well as substance P immunoreactivity in cell bodies of the dorsal root ganglia and in the substantia gelatinosa of the spinal dorsal horn that the cell bodies innervated. These results were determined by using both immunohistochemistry and radioimmunoassay. This study suggests that substance P may modulate nociception when lumbar nerve roots are stimulated mechanically. 相似文献