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1.
2.
Correlation of fetal posture and congenital dislocation of the hip   总被引:1,自引:0,他引:1  
A statistical study was carried out on the incidence of CDH associated with mechanical factors in the uterus, including congenital genu recurvatum. There were 72 cases of CDH among 6559 infants (1.1 per cent). The incidence of CDH was 0.7 per cent in cephalic presentation, 2 per cent in footling presentation and 20 per cent in single-breech presentation. In another series, CDH was found in six of seven infants with congenital genu recurvatum. These findings suggest that a fetal posture with the hip flexed and the knee extended predisposes to the development of CDH.  相似文献   
3.
Immunohistochemical study of bone GLA protein in primary bone tumors.   总被引:3,自引:0,他引:3  
METHODS. The immunoreactivity of bone GLA protein (BGP) in primary bone tumors, including osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma of bone (MFH), and giant cell tumor of bone (GCT), was investigated with anti-BGP rabbit serum and peroxidase-antiperoxidase complex. RESULTS. As to intracellular localization, BGP antigenicity was detected in 33 of 35 cases of osteosarcoma and 12 of 25 cases of chondrosarcoma. However, there were no positive findings in all 15 cases of MFH or 20 cases of GCT. In chondrosarcoma, the frequency of positively stained cases increased according to pathologic grading (i.e., 3 of 14 cases of Grade 1, 7 of 9 cases of Grade 2, and 2 of 2 cases of Grade 3). Although the multinucleated cells in MFH or GCT were not immunostained, BGP antigenicity was observed in the multinucleated cells of osteosarcoma (12 of 15 cases). In the matrix of osteosarcoma, BGP immunoreactivity of the tumorous osteoid was observed in 28 of 32 cases. However, in the matrices of chondrosarcoma, MFH, and GCT, BGP immunoreactivity was not observed. CONCLUSION. These results suggest that the immunohistochemical study of BGP is useful for the differential diagnosis of bone tumors.  相似文献   
4.
Kyphoscoliosis in congenital contractural arachnodactyly. A case report   总被引:1,自引:0,他引:1  
J Shikata  T Yamamuro  Y Mikawa  H Iida  N Nishimura 《Spine》1987,12(10):1055-1058
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5.
Bone scintigraphy was performed in 17 patients with previously known lung metastases of osteosarcoma. 99Tcm-MDP uptake was observed in all primary bone lesions but lung metastatic lesions were positive in only six patients (35%). 99Tcm-MDP uptake by lung metastases was significantly correlated with bone and osteoid formation in the metastatic lesions and preoperative serum ALPase values. These clinical observations were confirmed by using nude mice transplanted with human lung metastatic osteosarcoma. 99Tcm-MDP scintigraphy appears to be useful for detecting lung metastases of osteosarcoma only in a selected group of patients.  相似文献   
6.
Three sibs born to normal but consanguinous parents had flexion deformities of the thumb and fingers on one hand and sensory deficit in the other hand. Extensor muscles were absent or vestigial in all of them. Polyneuropathic electrophysiological findings were detected in 4 limbs. This is an apparently autosomal recessive trait previously unreported.  相似文献   
7.
Bone bonding behavior of three kinds of apatite containing glass ceramics   总被引:1,自引:0,他引:1  
We have produced three kinds of apatite-containing glass ceramics of the same chemical composition: MgO (4.6), CaO (44.9), SiO2 (34.2), P2O5 (16.3), CaF2 (0.5) (in weight ratio). They contain different crystal combinations and have different mechanical properties. The first glass ceramic (A-GC) was prepared by heating a glass plate to 870 degrees C. It contains only oxy- and fluoroapatite (35 wt%). The second glass ceramic (A-W-GC), and the third (A-W-CP-GC), were prepared by heating glass powder compacts to 1050 degrees C and 1200 degrees C, respectively. A-W-GC contains oxyapatite and fluoroapatite (Ca10(PO4)6(O,F2] (35 wt%) and beta-wollastonite (40 wt%). A-W-CP-GC contains oxyapatite and fluoroapatite (20 wt%), beta-wollastonite (CaO X SiO2) (55 wt%), and beta-whitlockite (3CaO X P2O5) (15 wt%). The bending strengths of A-GC, A-W-GC, and A-W-CP-GC were 88MPa, 178MPa, and 213MPa, respectively, in air. Rectangular ceramic plates (15mm X 10mm X 2mm) were implanted into a rabbit tibia. Ten and 25 weeks after implantation, the segment of tibia with implant was excised for examination. The segment was held by a special jig and the traction breaking load (failure load) was measured by an autograph. A-GC showed a lower load than A-W-GC and A-W-CP-GC. The loads for A-W-GC and A-W-CP-GC were almost equal. The failure loads did not change significantly between 10 and 25 weeks for any of the materials. The interface was examined by Giemsa surface staining, contact micro-radiography, and SEM-EPMA. Giemsa surface staining and CMR revealed direct bonding between the materials and the bone for all the three materials. SEM-EPMA showed that Si and Mg content decreased, Ca content did not change, and P content increased at the reaction zone between all three glass ceramics and bone. This was observed at 10 weeks, as well as at 25 weeks, after implantation. The reaction zone was narrowest with A-GC, wider with A-W-GC, and widest with A-W-CP-GC.  相似文献   
8.
The purpose of this study is to examine the formation of hydroxyapatite on the surface of glass-ceramics (chemical composition: SiO2, 34.2; P2O5, 16.3; CaO, 44.9; MgO, 4.6; CaF2, 0.5 in weight ratio). Two experiments were performed. In the first experiment, plates (2 x 25 x 25 mm) of glass-ceramics containing apatite-wollastonite (designated A.W-GC) were used. In the second experiment, plates (15 x 10 x 2 mm) of A.W-GC and its parent glass (designated G) were used. In each experiment, two paired specimens of identical material, one tied with silk thread, the other not tied, were implanted subcutaneously into rats. In both experiments, bonding to each other of both tied and untied specimens was observed one month after implantation. A pattern resembling hydroxyapatite was identified on the detached surface of the bonded A.W-GC by micro-beam x-ray diffraction. The weak crystalline pattern was also observed on the detached surface of bonded G samples. Analysis of the interface by SEM-EPMA showed that a calcium-phosphorus rich layer formed between the two bonded surfaces in both experiments. It is suggested that the bonding between the two materials was formed by the calcium-phosphorus rich layer, and that the calcium-phosphorus rich layer is virtually identical to hydroxyapatite.  相似文献   
9.
The formation of a bony spur or prominence at the anterior acromion is an important pathologic factor in impingement syndrome, and the detection and estimation of the size of such a spur are also important for diagnosis and treatment. We investigated the usefulness of a 30° caudal tilt view of the shoulder for detection of the bony spur. A 30° caudal tilt view was used to detect a spur in 52 of 73 joints diagnosed as having the impingement syndrome, whereas the spur was detected in only 27 joints when routine anteroposterior films were used. Only sufficiently larger spurs that projected toward the coracoid process could be recognized on anteroposterior films. Because the 30° caudal tilt view demonstrated the exact architecture of the spur encountered at operation, it was useful not only for preoperative planning but also for evaluation of the adequacy of surgery.  相似文献   
10.
Metals are essential for human life and physiological functions but may sometimes cause disorders. Therefore, we conducted acute toxicity testing of 50 metals in Daphnia magna: EC50s of seven elements (Be, Cu, Ag, Cd, Os, Au and Hg) were < 100 µg l?1; EC50s of 13 elements (Al, Sc, Cr, Co, Ni, Zn, Se, Rb, Y, Rh, Pt, Tl and Pb) were between 100 and 1000 µg l?1; EC50s of 14 elements (Li, V, Mn, Fe, Ge, As, In, Sn, Sb, Te, Cs, Ba, W and Ir) were between 1,001 and 100,000 µg l?1; EC50s of six elements (Na, Mg, K, Ca, Sr and Mo) were > 100,000 µg l?1; and. 7 elements (Ti, Zr, Bi, Nb, Hf, Re and Ta) did not show EC50 at the upper limit of respective aqueous solubility, and EC50s were not obtained. Ga, Ru and Pd adhered to the body of D. magna and physically retarded the movement of D. magna. These metals formed hydroxides after adjusting the pH. Therefore, here, we distinguished this physical effect from the physiological toxic effect. The acute toxicity results of 40 elements obtained in this study were not correlated with electronegativity. Similarly, the acute toxicity results of metals including the rare metals were also not correlated with first ionization energy, atomic weight, atomic number, covalent radius, atomic radius or ionic radius. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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