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81.
82.
A diagnosis of Hirschsprung's disease should be considered in children with constipation. An accurate neonatal history of bowel function and testing of anorectal pressure responses will aid the diagnosis. In the period 1971-75 inclusive, 140 children, aged 6 months to 14 years, were investigated by anorectal manometry. 26 showed a failed inhibition response to rectal dilatation, suggesting Hirschsprung's disease and were treated by anorectal myectomy. In 24 the disease was confirmed histologically. Two specimens were diagnostically unsuitable. 4 required repeat myectomies, and 3 anterior resection. At follow-up all had normal bowel movements without soiling.  相似文献   
83.
Initiation of translation of the animal picornavirus RNAs occurs via a mechanism of direct ribosome entry, which requires a segment of the 5' UTR of the RNA, known as the internal ribosome entry site (IRES). In addition, translation of the enterovirus and rhinovirus (HRV) subgroups requires cellular trans-acting factors that are absent from, or limiting in rabbit reticulocytes, but are more abundant in HeLa cell extracts. It has been shown previously that HeLa cells contain two separable activities, each of which independently stimulates HRV IRES-dependent translation when used to supplement reticulocyte lysate; one of these activities was identified as polypyrimidine tract-binding protein (PTB). Here, the purification of the second activity is achieved by use of an RNA-affinity column based on the HRV 5' UTR. It comprises two components: a 38-kD protein (p38), which is a novel member of the GH-WD repeat protein family and has no intrinsic RNA-binding activity; and a 96- to 97-kD protein doublet, which was identified as unr, an RNA-binding protein with five cold-shock domains. Coimmunoprecipitation with antibodies against either protein shows that the two proteins interact with each other, and thus p38 is named unrip (unr-interacting protein). Recombinant unr acts synergistically with recombinant PTB to stimulate translation dependent on the rhinovirus IRES. In contrast, unr did not significantly augment the PTB-dependent stimulation of poliovirus IRES activity.  相似文献   
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Ehlers-Danlos syndrome (EDS) is a heterogeneous connective tissue disorder that severely impairs the structure and function of the skin, joints, eyes and blood vessels. We have identified mutations of the COL5A2 gene, which encodes the alpha2(V) chain of type V collagen, in two unrelated patients with the severe type I form of EDS. The first proband was heterozygous for a 7 bp deletion that resulted in skipping of exon 27 while the second proband was heterozygous for a single nucleotide substitution that resulted in skipping of exon 28. Cultured dermal fibroblasts from both probands produced about equal amounts of the normal and mutant alpha2(V) mRNAs and protein chains. The dermis from the first proband contained a sparse collagen fibrillar network with great variability in collagen fibril sizes and shapes. The dermal collagens were also abnormally soluble. Bone cells from the first proband also produced about equal amounts of the normal and mutant alpha2(V) mRNAs. However, the collagen fibrillar architecture and collagen solubility of the bone matrix were normal. Our findings show that heterozygous mutations of the COL5A2 gene can produce the EDS type I phenotype. They also suggest that type V collagen plays a more important role in collagen fibrillogenesis of dermis than that of bone.   相似文献   
86.
Synovial chondromatosis in a facet joint of a cervical vertebra   总被引:2,自引:0,他引:2  
Kyriakos M  Totty WG  Riew KD 《Spine》2000,25(5):635-640
STUDY DESIGN: A case report of a cervical facet joint synovial chondromatosis. OBJECTIVES: To correlate the radiologic and histologic features of vertebral synovial chondromatosis with review of the literature. SUMMARY OF BACKGROUND DATA: Only two previous cases of vertebral facet joint synovial chondromatosis were found in a review of the English language medical literature. METHODS: A 39-year-old woman had severe cervical pain associated with neurologic signs and symptoms in the left upper extremity. Computed tomographic and magnetic resonance imaging studies were performed. RESULTS: Imaging studies showed lytic defects in the laminae of C3 and C4, with intermediate T1 and high T2 signal intensities. The diagnostic impression was that of a lymphangioma or synovial cyst. A laminectomy showed synovial tissue in both the C3-C4 facet joint and the lamina bone. Histologic examination disclosed synovial chondromatosis. CONCLUSIONS: Synovial chondromatosis of the vertebral spine is quite rare, this being only the third reported example. Direct invasion of the cancellous bone, as in this case, also is a very uncommon feature of chondromatosis. It is emphasized that when radiologic studies demonstrate a lesion with cartilaginous characteristics within or juxtaposed to a joint, synovial chondromatosis, despite its rarity, should be included in the differential diagnosis, regardless of the anatomic site.  相似文献   
87.
In a review of 364 radiocarpal and 123 distal radioulnar joint arthrograms we identified 44 (12%) patients with contrast defects at either the proximal or distal surface of the carpal triangular fibrocartilage complex (TFCC). Differences in their arthrographic characteristics distinguished two separate groups of patients; one with similar and another with dissimilar appearing TFCC surface contrast collections. Thirty-one of our 44 patients had similar appearing, isolated radial-sided collections at either the proximal or distal TFCC surfaces. Our arthrographic, demographic, and historical study of these patients suggests that the collections are not caused by traumatic partial TFCC tears but represent a normal anatomic variant, probably a synovial recess at the radial TFCC attachment. Arthrography and dissection of a limited number of cadaveric specimens confirmed this conclusion. The second group included the remaining 13 patients. This group had contrast collections at either the proximal or distal TFCC surface, which varied in location and appearance. This smaller group is more likely to represent those uncommon patients with partial TFCC defects caused by tears.  相似文献   
88.
The CD3 antigen was purified from human tonsils by immunoaffinity chromatography and preparative SDS-PAGE; the overall yield was 10%. Amino acid sequence analysis of the separated gamma, delta and epsilon polypeptides revealed that the gamma and epsilon polypeptides were blocked at the N-terminus, whereas the partial N-terminal amino acid sequence for the delta chain was identical to that described by Borst et al. [Nature 312, 455-485 (1984)]. The gamma and epsilon chains were cleaved with formic acid and cyanogen bromide respectively in order to obtain amino acid sequence data. The sequences obtained corresponded exactly to the amino acid sequences deduced from the nucleotide sequences of putative gamma and epsilon cDNA clones.  相似文献   
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90.
One hundred sixty-two patients had analyses for correlation of triangular fibrocartilage abnormalities (TFCC), with duration and location of pain and other possible associated radiographic, scintigraphic, and arthrographic abnormalities. Results indicated that TFCC perforations did not correlate with any pain complex or other associated radiographic, arthrographic, or scintigraphic abnormality. No association with carpal instability or with ulnar variance could be identified. No definition between perforations that were posttraumatic and those that were the results of a degenerative process could be made. Several small defects on both the proximal and distal surfaces of the TFCC were identified. They do not appear to have been reported previously in the literature. Their significance is discussed.  相似文献   
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