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991.
992.
The critical attitude towards the additional chemotherapy of the mamma carcinoma is justified by the results of 453 patients submitted to post-operative irradiations. With the indication corresponding to their stade, 43 patients were treated by chemotherapy according to Ward. The remission rate was 70%. 相似文献
993.
994.
SIM and SIM · R mice were bred for congenicity at the Fv-1 locus. In addition to a difference in their permissiveness for infection by murine C-type viruses, presumably due to Fv-1, these mice differ in antigens determining histocompatibility. 相似文献
995.
Frick C Dietz AC Merritt K Umbreit TH Tomazic-Jezic VJ 《Journal of long-term effects of medical implants》2006,16(6):423-433
The main causes for the long-term prosthetic implants' failure are the body's reaction to the implanted material or mechanical stress on the device resulting in the formation of wear particles. Particulate wear debris attracts macrophages, and depending on the chemical composition of the material and particle size, various levels of inflammatory response may occur. While transient inflammation is common, development of chronic inflammation may have serious consequences, leading to implant failure. Such a process may also cause systemic changes to immune functions and long-term effects on the host immune responses. In this study, we evaluated the effects of polystyrene (PS), polyethylene (PE), and polymethylmethacrylate (PMMA) particles on macrophage function and the generation of T-cell responses. Particles of various diameters were injected intraperitoneally into Balb/c mice, and immune functions were examined at 3, 10, and 21 days after the injection. The intensity of phagocytosis by peritoneal exudate cells (PECs) and the proliferative response of spleen cells from treated mice were evaluated. Enumeration of PECs revealed an increase in the total number of cells. Mice injected with PS or PE particles had a higher percentage of cells containing particles than PMMA-injected mice. Macrophages with PS or PE particles tended to adhere to and/or infiltrate peritoneal fibro-fatty tissues surrounding the spleen and pancreas, while the PMMA-carrying macrophages infiltrated the spleen, resulting in an increase of spleen size and "weight. The spleen cell proliferation assay revealed only mild and transient effects on the mitogen response in both PE and PS particle-injected mice. However, in the PMMA-injected mice we observed a lasting increase of the Con A response and a decrease of the LPS response. In vitro exposure of PECs from untreated mice showed a dose-response pattern in nitric oxide (NO) and TNFalpha production. While exposure to either PMMA or PE induced comparable levels of NO, exposure to PMMA induced a markedly higher production of TNFalpha than exposure to PE.The results indicate that particulate biomaterials may, in addition to the initial activation of phagocytes, significantly affect immune functions and compromise the host response to other antigenic stimuli. 相似文献
996.
Sama W Dietz K Smith T 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2006,100(9):811-816
Survival time data of Plasmodium falciparum infections from deliberate infection of human subjects with P. falciparum between 1940 and 1963 as a treatment for neurosyphilis in the USA (Georgia) have been used to test the fits of five commonly used parametric distributions for survival times using quantile-quantile plots. Our results suggest that the best fit is obtained from the Gompertz or Weibull distributions. This result has important implications for mathematical modelling of malaria, which has for the past century exclusively assumed that the duration of malaria infections has an exponential distribution. It is desirable to know the correct distribution because its shape profoundly influences the length of monitoring needed in an intervention programme for eliminating or reducing malaria. 相似文献
997.
A computerized vector manometry and MRI study in children following posterior sagittal anorectoplasty 总被引:2,自引:0,他引:2
The study was designed to evaluate computerized eight-channel vector manometry (8CVM) and pelvic floor magnetic resonance
imaging (MRI) as methods to assess the anal sphincter following posterior sagittal anorectoplasty (PSARP) for anorectal malformations,
in particular the functional capacity of the sphincter structures in correlation with postoperative MRI findings. Seventeen
children had been operated upon for a rectovesical, -urethral, or -vaginal fistula including one female cloacal malformation;
4 had a secondary PSARP. Mean follow-up was 5.57 years. Continence was evaluated with a modified Kelly score. A CVM technique
with an eight-channel perfusion catheter was used. In addition to software-supported data, the manometric parameters included
a score-system assessing three different pressure zones of the anal canal qualitatively on the three-dimensional image of
the anal sphincter profile. The same procedure was performed on sagittal, oblique axial, and oblique coronal MRI. Furthermore,
the thickness of the sphincter muscle was assessed at the level of the maximal mean segmental pressure. All children had decreased
absolute vector-volumetry values at rest and on squeezing. Correlation with the clinical score was poor. Correlation of the
manometric score with the clinical course was similar to the correlation of MRI score with clinical course (R = 0.425; P = 0.1). Thirteen children demonstrated normal or increased sphincter length; 5 of these had a decreased high-pressure zone
(HPZ). The position of the anorectum in the sphincter muscles could be evaluated by the vector-volumetry image as anatomic
in 11 cases, nearly correctly positioned in 4, and ectopic in 1 child. MRI detected 2 cases of malposition, 10 anatomic, and
4 nearly-anatomic findings. Correlation of the manometric score with the MRI score and the thickness of the sphincter muscle
at the HPZ was significantly high (R = 0.801; P < 0.0001). 8CVM is thus highly sufficient in illustrating the function of the sphincter musculature seen on pelvic floor
MRI. Both methods only moderately reflect clinical follow-up, since continence depends on more than sphincter ability.
Accepted: 9 March 2000 相似文献
998.
Fouad K Bastiaanse CM Dietz V 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,137(2):133-140
Load dependent reflex adaptations were studied in healthy subjects walking on a split-belt treadmill. Compensatory reflex responses were elicited in the right leg extensor muscles during mid-stance by a short acceleration of the right treadmill belt. Electromyographic activity (EMG) was recorded from the right medial gastrocnemius (GMR), soleus (SO) and tibialis anterior (TA) muscles of the right leg as well as from the gastrocnemius of the left unperturbed leg (GML). To study the adaptational reflex behavior, multiple measurements were taken during walking with normal (control) and increased body load and after removing the load. In most experiments the compensatory EMG response in the GMR consisted of a short inhibitory and a subsequent excitatory component. Both reflex components were larger when the body was loaded. During the course of continuous loading, divergent reflex adaptations of different degrees and directions were observed in the subjects. In one group of subjects the reflex response increased to a higher level of EMG activity. In a second group EMG activity first increased and afterwards decreased to baseline level. A subsequent removal of body loading resulted in a slow adaptation to the control reflex values in both groups. Neither the EMG activity in the GM nor the reflex responses in the GMR after increasing the load changed differently in the two groups. Our results suggest that load information is not simply used in a fixed input/output relationship of the actual biomechanical conditions of a subject. Load information is rather used to slowly modify the reflex response, to achieve the desired posture during walking. 相似文献
999.
1000.