全文获取类型
收费全文 | 548篇 |
免费 | 30篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 29篇 |
妇产科学 | 4篇 |
基础医学 | 52篇 |
口腔科学 | 40篇 |
临床医学 | 50篇 |
内科学 | 154篇 |
皮肤病学 | 6篇 |
神经病学 | 5篇 |
特种医学 | 108篇 |
外科学 | 27篇 |
综合类 | 9篇 |
预防医学 | 35篇 |
眼科学 | 2篇 |
药学 | 27篇 |
中国医学 | 3篇 |
肿瘤学 | 45篇 |
出版年
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 12篇 |
2018年 | 8篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 14篇 |
2014年 | 12篇 |
2013年 | 25篇 |
2012年 | 10篇 |
2011年 | 11篇 |
2010年 | 27篇 |
2009年 | 30篇 |
2008年 | 12篇 |
2007年 | 18篇 |
2006年 | 10篇 |
2005年 | 17篇 |
2004年 | 21篇 |
2003年 | 5篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 29篇 |
1997年 | 33篇 |
1996年 | 26篇 |
1995年 | 24篇 |
1994年 | 24篇 |
1993年 | 21篇 |
1992年 | 14篇 |
1991年 | 11篇 |
1990年 | 7篇 |
1989年 | 14篇 |
1988年 | 16篇 |
1987年 | 9篇 |
1986年 | 15篇 |
1985年 | 13篇 |
1984年 | 11篇 |
1983年 | 9篇 |
1982年 | 12篇 |
1981年 | 7篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 6篇 |
1941年 | 1篇 |
排序方式: 共有597条查询结果,搜索用时 15 毫秒
81.
82.
Carpino A; Siciliano L; Petroni MF; De Stefano C; Aquila S; Ando S; Petrone MF$corrected to Petroni MF 《Human reproduction (Oxford, England)》1998,13(1):111-114
Total seminal zinc concentration, seminal zinc fraction bound to high
molecular weight proteins (HMW-Zn%) and zinc content in spermatozoa were
assayed in the ejaculates of 90 asthenozoospermic patients subdivided into
two study groups: normoasthenozoospermics (group I: n = 50) and
oligoasthenozoospermics (group II: n = 40). The zinc concentrations of
patients were compared with those of a control group of donors showing
normal semen parameters. All samples were also investigated for their sperm
membrane functional integrity by the hypo- osmotic swelling test (HOS). The
results showed normal total zinc concentrations but very low HMW-Zn% values
(P < 0.001) in seminal plasma of the two groups of asthenozoospermic
patients compared to the controls. Furthermore higher zinc amounts (P <
0.001) were measured in spermatozoa of oligoasthenozoospermic patients
compared to group I and to the control group. Oligoasthenozoospermics also
displayed a lower HOS score (P < 0.001) compared to the other two
groups. These data suggest that the increased unbound seminal zinc could
contribute to the decrease of sperm motility in normoasthenozoospermic and
oligoasthenozoospermic patients. A further impairment in sperm motility
could occur in the oligoasthenozoospermic patients where the increase of
seminal free zinc was followed by a major zinc uptake by spermatozoa. The
higher intrasperm zinc content in these patients could be a reflection of
their low sperm membrane functionality.
相似文献
83.
Magnuson JE; Brown ML; Hauser MF; Berquist TH; Fitzgerald RH Jr; Klee GG 《Radiology》1988,168(1):235-239
When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively. 相似文献
84.
The pulmonary manifestations of sarcoidosis are varied. This report describes a patient with rapidly progressive pulmonary sarcoidosis which had several unusual features and presented with acute pneumonia with air bronchograms on chest radiographs. Gallium-67 scanning and serum angiotensin-converting enzyme estimations aided in the diagnosis and in determining the response to steroid therapy. 相似文献
85.
Pflugfelder PW; Wendland MF; Holt WW; Quay SC; Worah D; Derugin N; Higgins CB 《Radiology》1988,167(1):129-133
Cardiac-gated magnetic resonance (MR) imaging was performed in rats to determine the effects of manganese ethylenediaminetetraphosphonate (TP). Ten normal rats received Mn-TP in a dose of 50 mumol/kg through a tail-vein injection. Spin-echo MR images were obtained before and every 10 minutes after Mn-TP injection for 1 hour. Cardiac signal intensity (SI) increased more than 70% after Mn-TP injection and remained nearly unchanged 1 hour after injection. Myocardial T1 was 517 +/- 49 msec in eight control rats and 282 +/- 61 msec (P less than .001) in six rats 81 +/- 0 minutes after injection. Nine rats underwent occlusion of the left anterior descending coronary artery prior to MR imaging. Images were obtained before and 15, 30, and 60 minutes after Mn-TP injection. In normal myocardium, SI increased up to 82% and remained elevated for 1 hour. In ischemic myocardium, SI rose 11%, leading to a marked contrast between the two tissue zones. T1 was also different in the two regions: In normal tissue, it was 206 msec +/- 54; in ischemic tissue, 338 +/- 82 (P less than .001). With T1-weighted MR imaging, Mn-TP showed a potential for delineating the jeopardized area after acute myocardial ischemia. 相似文献
86.
87.
88.
89.
90.
McCarthy J McLeod CJ Minners J Essop MF Ping P Sack MN 《Journal of molecular and cellular cardiology》2005,38(4):697-700
Modest cardiac-overexpression of constitutively active PKCepsilon (aPKCepsilon) in transgenic mice evokes cardioprotection against ischemia. As aPKCepsilon interacts with mitochondrial respiratory-chain proteins we hypothesized that aPKCepsilon modulates respiration to induce cardioprotection. Using isolated cardiac mitochondria wild-type and aPKCepsilon mice display similar basal mitochondrial respiration, rate of ATP synthesis and adenosine nucleotide translocase (ANT) functional content. Conversely, the aPKCepsilon mitochondria exhibit modest hyperpolarization of their inner mitochondrial membrane potential (DeltaPsi(m)) compared to wild-type mitochondrial by flow cytometry. To assess whether this hyperpolarization engenders resilience to simulated ischemia, anoxia-reoxygenation experiments were performed. Mitochondria were exposed to 45 min anoxia followed by reoxygenation. At reoxygenation, aPKCepsilon mitochondria recovered ADP-dependent respiration to 44 +/- 3% of baseline compared to 28 +/- 2% in WT controls (P = 0.03) in parallel with enhanced ATP synthesis. This preservation in oxidative phosphorylation is coupled to greater ANT functional content [42% > concentration of atractyloside for inhibition in the aPKCepsilon mitochondria vs. WT control (P < 0.0001)], retention of mitochondrial cytochrome c and conservation of DeltaPsi(m). These data demonstrate that mitochondria from PKCepsilon activated mice are intrinsically resilient to anoxia-reoxygenation compared to WT controls. This resilience is in part due to enhanced recovery of oxidative phosphorylation coupled to maintained ANT activity. As maintenance of ATP is a prerequisite for cellular viability we conclude that PKCepsilon activation augmented mitochondrial respiratory capacity in response to anoxia-reoxygenation may contribute to the PKCepsilon cardioprotective program. 相似文献