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排序方式: 共有201条查询结果,搜索用时 15 毫秒
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F. KOVÁ M. POSPÍIL I. TREBICHAVSKÝ J. HOFMAN J. KOSTKA 《Scandinavian journal of immunology》1978,8(S8):279-288
In studies of the cellular localization of AFP with the use of immunofluorescent, immunochemical and immunoautoradiographic techniques we concentrated in the course of prenatal ontogeny of pigs on the mesenchymal haemopoictic population of lymphatic and haemopoietic organs of these animal species. A marked AFP positivity was demonstrated already in haemopoietic cells of yolk sac, but also in other organs of embryonic and fetal haemopoiesis. In the course of intrauterine development the percentage of AFP-positive haemopoietic cells decreases and postnatally the AFP positivity of haemopoietic cells does not occur. The decrease in AFP-positivity of haemopoietic fetal cells is in correlation with the subsequent decrease in the intensity of extramedullary haemopoiesis. In the system in vitro the inhibitory effect of pig AFP on T and B cell mitogen-induced blast transformation of lymphocytes was demonstrated, similarly as on the mixed lymphocyte reaction. That effect of AFP is dependent on its presence in the first 24 hrs of stimulation and is not species specific. In fetal cell suspensions of lymphatic and haemopoietic organs of pigs their capacity for blastogenic transformation with anti-AFP serum was demonstrated. 相似文献
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自异型南五味子(Kadsure heteroclita)首次分得7个已知的联苯环辛烯类木脂素,tigloylgomisin P(1),angeloylgomisin P(2),gomisin A(3),五味子素(4),angeloylgomisin H(5),gomisin B(6),R(+)-gomisin M(7)。tigloylgomisin P(1)的构型以二维核磁共振光谱技术确定。应用[~3H]血小板活化因子(PAF)结合人血小板膜的分析方法测定,证明化合物(1),(2)和(7)有 PAF 受体拮抗活性。 相似文献
157.
Saini S; Stark DD; Rzedzian RR; Pykett IL; Rummeny E; Hahn PF; Wittenberg J; Ferrucci JT 《Radiology》1989,173(1):111-116
The ability of an ultrafast magnetic resonance (MR) imaging technique to provide abdominal MR images free of motion artifacts was studied. Individual T2-weighted transverse MR images were acquired in as little as 40 msec on a whole-body system operating at 2.0 T. Clinical evaluation was undertaken with fat-suppressed images in which only protons of water molecules contributed to image signal intensity. The ultrafast MR images were compared with conventional MR images obtained at 0.6 T. In 22 patients and two healthy volunteers, ultrafast MR images were of diagnostic quality and free of motion artifacts. Images obtained at an echo time (TE) of 30 msec (imaging time, 40 msec) had liver signal-to-noise ratios of 56.3 +/- 22.6 (n = 19). Because of a smaller data matrix, ultrafast MR images had soft-tissue interfaces that were less sharp than those of the highest-quality conventional MR images in which no motion artifacts were present. However, ultrafast MR images demonstrated high T2-dependent soft-tissue contrast, and pathologic and normal anatomies were readily detected with both imaging techniques. This ultrafast imaging technique has significant promise in whole-body MR imaging, in which motion artifacts often degrade image quality. 相似文献
158.
Mitchison HM; Hofmann SL; Becerra CH; Munroe PB; Lake BD; Crow YJ; Stephenson JB; Williams RE; Hofman IL; Taschner PEM; Martin JJ; Philippart M; Andermann E; Andermann F; Mole SE; Gardiner RM; O'Rawe AM 《Human molecular genetics》1998,7(2):291-297
A subtype of neuronal ceroid lipofuscinosis (NCL) is well recognized which
has a clinical course consistent with juvenile NCL (JNCL) but the
ultrastructural characteristics of infantile NCL (INCL): granular
osmiophilic deposits (GROD). Evidence supporting linkage of this phenotype,
designated vJNCL/GROD, to the INCL region of chromosome 1p32 was
demonstrated (pairwise lod score with D1S211 , Z max = 2.63, straight theta
= 0.00). The INCL gene, palmitoyl-protein thioesterase (PPT ; CLN1), was
therefore screened for mutations in 11 vJNCL/GROD families. Five mutations
in the PPT gene were identified: three missense mutations, Thr75Pro,
Asp79Gly, Leu219Gln, and two nonsense mutations, Leu10STOP and Arg151STOP.
The missense mutation Thr75Pro accounted for nine of the 22 disease
chromosomes analysed and the nonsense mutation Arg151STOP for seven. Nine
out of 11 patients were shown to combine a missense mutation on one disease
chromosome with a nonsense mutation on the other. Mutations previously
identified in INCL were not observed in vJNCL/GROD families. Thioesterase
activity in peripheral blood lymphoblast cells was found to be markedly
reduced in vJNCL/GROD patients compared with controls. These results
demonstrate that this subtype of JNCL is allelic to INCL and further
emphasize the correlation which exists between genetic basis and
ultrastructural changes in the NCLs.
相似文献
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Studies of percutaneous epididymal sperm aspiration (PESA) and intracytoplasmic sperm injection 总被引:3,自引:0,他引:3
Meniru GI; Gorgy A; Batha S; Clarke RJ; Podsiadly BT; Craft IL 《Human reproduction update》1998,4(1):57-71
Four distinct studies were carried out using two data sets ofpercutaneous epididymal sperm aspiration (PESA) and intracytoplasmicsperm injection (ICSI) procedures performed from March 1993to January 1997. In study A, an analysis of 181 ICSI treatmentcycles following PESA revealed a successful epididymal spermretrieval rate of 83%. It confirmed that PESA is an effectivesperm retrieval method and the associated ICSI pregnancy rate(35% per embryo transfer) compared favourably with that of othersperm retrieval methods. In study B, the relevance of a priordiagnostic PESA procedure was ascertained by comparing the spermretrieval rates in two groups of patients having their firstICSI treatment cycle with spermatozoa retrieved through PESA.Group B1 (n=50) had diagnostic PESA prior to the ICSI treatmentcycle PESA procedure, unlike patients in group B2 (n=64) whodid not. The sperm retrieval rate in the treatment cycle procedurewas not different at 90 and 82.8% for groups B1 and B2 respectively.However, the discontinuation of diagnostic PESA is fraught withproblems including liability to medico-legal sanctions. In studyC, analysis of 177 treatment cycles involving PESA and ICSIrevealed a successful sperm retrieval rate by PESA of 82% inthe first cycle, 93% in the second, 96% in the third and 100%in the fourth cycle. The same trend was evident when sperm retrievalwas examined in relation to each of the epididymides. Retrievedspermatozoa were found to be motile in 67-100% of cases andthe frequency of samples containing motile spermatozoa did notdecrease with increase in the number of PESA attempts. Theseresults show that PESA does not jeopardize future epididymalsperm retrieval. In study D, the outcome of treatment with ICSIusing ejaculated spermatozoa (305 cycles) (group D1) was comparedwith that of ICSI using spermatozoa obtained through PESA (54cycles) (group D2). The median age of women in the two groupsof couples was similar (34 years). In group D1, 70% of metaphaseII oocytes were fertilized compared with 61% in group D2 (P<0.01).The cleavage rate and the median numbers of transferred andcryopreserved embryos were similar in both groups. There wasno significant difference between the clinical pregnancy rates(33 and 42% in groups D1 and D2 respectively). Our results showthat the outcome of PESA-ICSI treatment compared favourablywith that of ICSI using ejaculated spermatozoa. 相似文献