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941.
Thomas J. Lescher M.D. Major MC David K. Teegarden M.D. Major MC Basil A. Pruitt Jr. M.D. Colonel MC 《Diseases of the colon and rectum》1978,21(8):618-622
Summary and Conclusions Five (1 per cent) of 529 thermally injured patients experienced pseudo-obstruction of the colon over a two-year period. All
patients had classic non-painful abdominal distention. Infection was the most common associated problem and possible triggering
mechanism in these patients. After confirmation of the colonic dilation on a plain abdominal roentgenogram, distal obstruction
was ruled out by contrast enema. Occasionally, Gastrografin enema seemed to ameliorate the distention.
Conservative medical management should be attempted initially. Colonoscopy should be employed at the earliest possible time.
Exploratory laparotomy and tube cecostomy are usually adequate when surgical decompression is necessary.
Patients who have accompanying small-intestinal distention seemed to tolerate this condition better, possibly due to a decompressing
effect of an incompetent ileocecal valve. “Hinge-type” kinks, which occur in time at both hepatic and splenic flexures, become
obstructing in themselves, and can be a barrier to conservative treatment.
Read at the meeting of the American Society of Colon and Rectal Surgeons, San Diego, California, June 11 to 15, 1978.
The opinions or assertions contained herein are the private view of the authors and are not to be construed as official or
as reflecting the view of the Department of the Army or the Department of Defense. 相似文献
942.
943.
Localization of erythropoietin synthesizing cells in murine kidneys by in situ hybridization 总被引:14,自引:1,他引:14
In situ hybridization was used to localize the cells that produce erythropoietin (EP) in anemic murine kidneys. Kidneys from anemic and nonanemic mice were fixed and processed for paraffin embedding. Sections were hybridized with a 35S-labeled RNA probe complementary to mRNA coding for EP. An uncommon, but specific type of cell was intensely labeled in the cortices of anemic kidneys. The labeled cells were clearly nonglomerular and nontubular. Their location outside of the tubular basement membrane was consistent with that of a subset of interstitial cells or capillary endothelial cells. 相似文献
944.
While a solution of Adolph's Meat Tenderizer® (AMT) is commonly used to treat esophageal meat impaction, few studies describe its clinical effects. We examined AMT with regard to (1) its papain activity; (2) its ability to digest meat cubesin vitro; and (3) its effect on rabbit esophageal mucosa. A standard papain assay was developed against which the activity of AMT was compared. Proteolytic activity was detected in AMT only when the papain activators, 0.02 M cysteine and 0.008 M EDTA, were added to the system. Meat cubes incubated in AMT solution exhibited no evidence of digestion as determined by protein release or change in sample weight. A solution of AMT had no adverse effect on normal esophageal mucosa in rabbits, but significantly increased esophagitis when infused onto previously inflamed mucosa. We conclude that AMT solution has no inherent capacity to digest or to reduce the size of an impacted meat bolus, and may, in fact, worsen existing esophagitis.The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army or the Department of Defense.Presented at the Twelfth Annual William Beaumont Gastrointestinal Symposium, March 23–25, 1983, El Paso, Texas.Address for reprint requests: Technical Publications Editor, Letterman Army Medical Center, Presidio of San Francisco, California 94129. 相似文献
945.
Morimoto K; Robin E; Le Bousse-Kerdiles MC; Li Y; Clay D; Jasmin C; Smadja- Joffe F 《Blood》1994,83(3):657-662
Hyaluronan-binding function of the CD44 molecule has not been so far detected in myeloid cells. To study pure populations of primitive myeloid cells, we investigated the hyaluronan-binding function of the CD44 molecule from three myeloid cell lines: KG1a, KG1, and HL60. Both KG1a and KG1 cells express the CD34 antigen characteristic of the hematopoietic stem cells and HL60 cells do not; accordingly, KG1a and KG1 cells are generally considered as the most primitive and HL60 cells as the most mature of these cell lines. Measurement of cell adhesion to hyaluronan-coated surfaces (using 51Cr-labeled cells) and of aggregate formation in hyaluronan-containing solutions, showed that 45% of KG1 cells and 22% to 24% of KG1a spontaneously bind to hyaluronan, whereas HL60 cells do not either spontaneously or after treatment with a phorbol ester. Hyaluronan binding by KG1a and KG1 cells is mediated by CD44, because it is specifically abolished by monoclonal antibodies (MoAbs) to this molecule. The binding might require phosphorylation by protein kinase C and perhaps also by protein kinase A, because it is prevented by staurosporine, which inhibits these enzymes. 12-O- tetradecanoylphorbol-13-acetate (TPA) which activates protein kinase C, rises to 80% the proportion of KG1 and KG1a cells that bind hyaluronan; this activation is dependent on protein synthesis, for it is abrogated by cyclophosphamide, a protein synthesis inhibitor. Binding of TPA- treated cells to hyaluronan is only partly inhibited by MoAb to CD44: this suggests that TPA may induce synthesis of a hyaluronan-binding protein distinct from CD44. Considering the abundance of hyaluronan in human bone marrow, these results suggest that CD44 may be involved in mediating precursor-stroma interaction. 相似文献
946.
947.
948.
N. D. Yeomans MB MRACP Dr. D. J. B. St. John MB FRACP MRCP W. G. R. M. de Boer MD FRCPA MC 《Digestive diseases and sciences》1973,18(9):773-780
Regeneration of gastric mucosa damaged by aspirin was studied in 6-week-old rats, using histologic and autoradiographic technics. Aspirin (120 mg/kg) was given by esophageal intubation either in a single dose or each day for 14 days. After a single dose, two types of lesion were observed in the mucosa of the body of the stomach: (a) superficial erosions which were already present after 30 minutes and which completely healed within 24 hours; (b) deeper erosions, reaching maximal numbers at 4 hours, which healed slowly with a median disappearance time of 5 days and which were associated with a focal increase in3H-thymidine-labeled cells. The peak increase in labeling occurred between 16 and 48 hours. The pattern and rate of healing was not altered by repeated daily aspirin. The investigation has demonstrated slow healing of deep mucosal erosions caused by aspirin; the slow healing can be explained by destruction of the progenitor zone by the initial injury.Supported by the National Health and Medical Research Council and the Alfred Hospital.Presented in part to the Australian Society for Medical Research, December 1971. 相似文献
949.
Tebib JG; Reynaud C; Cedoz JP; Letroublon MC; Niveleau A 《Rheumatology (Oxford, England)》1997,36(9):990-995
The levels of the five methylated nucleosides pseudouridine (psi-Urd),
1-methyladenosine (1-MeAdo), 4 acetylcytidine (4-AcCyd), 1 methylinosine
(1-Melno) and 7 methylguanosine (7-MeGuo) resulting from RNA degradation
were examined in the urine of rheumatoid arthritis (RA) patients. Of these
five, 1-MeAdo and psi-Urd were correlated with the active phase of the
disease, while two others (4-AcCyd and 1-Melno), which require further
evaluation, appeared to be linked to the prognosis of the disease. As RNA
turnover is closely associated with cell proliferation, including that of
lymphocytes in RA, there may be a hitherto unsuspected benefit in measuring
1-MeAdo and psi-Urd as biochemical markers of RA disease activity.
相似文献
950.
Red blood cell (RBC) adhesion to the vascular endothelium is increased in several pathologic conditions, including sickle cell disease and malaria. However, RBC interactions with components of the subendothelial matrix are not well-characterized. Under in vitro flow conditions of 1 dyne/cm2, washed RBCs bound to the purified adhesive molecules thrombospondin (TSP) and laminin. Sickle RBCs had the greatest adhesion of all tested RBCs. The adhesion of sickle RBCs to immobilized TSP was inhibited by the anionic polysaccharides high molecular weight (MW) dextran sulfate and chondroitin sulfate A, but not other anionic polysaccharides of similar structure and/or charge density. These data were consistent with the RBC adhesive molecule being a sulfated glycolipid. Therefore, TSP-binding lipids from normal and sickle RBCs were isolated and characterized. The TSP-binding lipid was purified by alkaline methanolysis, anion exchange chromatography and preparative thin layer chromatography (TLC). A homogeneous band on TLC was identified using a specific overlay TSP-binding assay. TSP binding to the purified lipid was stable to bass and neuraminidase treatment, labile to acid treatment, and was inhibited by high MW dextran sulfate, similar to that seen with intact RBCs binding to immobilized TSP under conditions of flow. In addition, soluble laminin bound to the purified RBC lipid. This acidic TSP- and laminin-binding lipid(s) isolated from both sickle and normal RBC membranes may contribute to erythrocyte interactions with the subendothelial matrix, hereby participating in the pathogenesis of vaso-occlusive diseases. 相似文献