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991.
992.
Human depression is partly a congenital disorder. Aspects of the behavior accompanying depression can be magnified by genetic manipulation of bred animal species. Learned Helplessness (LH) is a trait-mark behavior that successfully breeds in rodents. Here, 'congenital' LH (cLH) rats were trained to recognize and respond to 12s long interval cues (irt>12s schedule). Rats compliant to an irt>t schedule will space responses evenly and respond rhythmically. Irt>t schedule derived data are plotted in histograms showing irt (interresponse time) frequencies. A pause response peak emerges, for outbred rats, at irt values approximating the minimum interval for reinforcement. cLH rats [n=9] complied poorly to schedule contingencies when diluent (vehicle) was injected before testing. Moderate and high dose injections of a CB 1 receptor selective agonist drug (AM 411), however, increased operant schedule compliance and normalized the cLH rats' irt>t histogram distributions. Performance indicators for cLH rats are presented alongside coordinate measures from a comparison group [n=5] of normally bred Sprague-Dawley (SD) rats. In both cLH and SD rats, treatment session histograms revealed shifts of the pause response peak not accompanied by a change in motor responsiveness. The irt>12s histogram shifts were absent when AM 411 dosages were arranged to follow pre-medication injections of a CB 1 receptor selective antagonist drug (AM 251). In short, AM 411 increased timing acuity in rats prone to behavioral despair but had opposite timing effects in normally bred SD rats. 相似文献
993.
Mathur SP Mathur RS Gray EA Lane D Underwood PG Kohler M Creasman WT 《Gynecologic oncology》2005,98(3):467-483
OBJECTIVES: An early non-invasive diagnosis of cervical cancer and its metastasis can save lives. We have shown that serum IGF-II levels can be effectively used for a specific early diagnosis of cervical cancer. Here, we shall determine if serum levels of vascular endothelial growth factors B and C (VEGF-A [corrected] VEGF-C) associated with vasculogenic and lymphogenic metastasis may be used for an early diagnosis of advanced metastatic cervical cancer and compare these levels with those of the serum IGF-II and IGF-binding protein 3 (IGF-BP3). MATERIAL AND METHODS: (a) Serum levels of IGF-II, IGF-BP3, VEGF-A [corrected] (VEGF(165)) and VEGF-C (ELISA kits) were determined in: 82 controls with normal Pap smears; 29 women with atypical squamous cells of undetermined significance (ASCUS) and normal cervical biopsy; 46 ASCUS and cervical intraepithelial neoplasia (CIN) on biopsy; 8 pre-therapy CIN-I; 23 successfully treated CIN-I; 75 persistent CIN-I; 14 CIN-II/III pre-therapy; 14 successfully treated CIN-II/III; 70 persistent CIN-II/III; 86 pre-therapy cervical cancer; 26 in early grades of cervical cancer; 21 in late grades of cervical cancer; 22 cervical cancer patients in remission; 50 persistent cervical cancer; 18 with ovarian cancer; and 57 with endometrial cancer. (b) Serial serum samples collected over 5 years in 5 women with progressing cervical cancer were also tested. (c) Serum and tissue VEGF-C were enumerated in 20 matched serum (ELISA) and tissue (semi-quantitative immunofluorescent antibody assay) samples from controls, early cervical cancer, late cervical cancer, ovarian cancer and endometrial cancer patients. Student's t test, chi-square analysis and linear regression analysis were used. RESULTS: (a) As anticipated, serum IGF-II levels were elevated as early as ASCUS with CIN on biopsy and continued to be elevated in CIN (all grades; pre-therapy and persistent) and cervical cancer (pre-therapy, early, late and persistent). Serum IGF-II levels were normal in ASCUS with normal biopsy, successfully treated CIN-I, II/III, cervical cancer as well as pre-therapy ovarian and endometrial cancers (therapy efficacy: P < 0.0001 by chi-square analysis). Serum IGF-BP3 showed a significant decrease with advancing disease. Serum VEGF-A [corrected] levels were the highest in pre-therapy, early, advanced and persistent cervical cancer, as well as in ovarian and endometrial cancers. Serum VEGF-C levels, on the other hand, were the highest in late and persistent cervical cancers, but not in ovarian or endometrial cancers. (b) In the 5 women with serial samples, the serum levels of the growth factors showed similar trends. (c) VEGF-C levels in serum and tissue were elevated in cervical cancers especially in advanced grades, while they were normal in serum and tissue from the controls and women with ovarian and endometrial cancers. There was a highly significant positive correlation between VEGF-C and IGF-II and a negative correlation between IGF-BP3 and VEGF-C (P < 0.0001). CONCLUSION: Serum IGF-II up-regulation is specific to cervical cancer and helps in the early diagnosis of malignant proliferation, while serum VEGF-C up-regulation appears to be a unique marker for an early diagnosis of cervical cancer metastasis. VEGF-C and IGF-II systems appear to be interrelated in cervical cancer, contributing to the early malignant cell proliferation and lympho-vascular metastasis. Serum IGF-BP3 and VEGF-A [corrected] appear to be common markers for all gynecological cancers. 相似文献
994.
Leitender Arzt Dr. H. Kohler 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1932,237(7-9):756-760
Zusammenfassung Durch einen Hufschlag auf den Bauch wurde das Duodenum im retroperitonealen Teil zirkul?r abgequetscht, obwohl die Gewalteinwirkung
so gering war, da? innerhalb der Bauchh?hle keine Organsch?digungen eingetreten waren. -Es empfiehlt sich daher, auch bei
Fehlen nennenswerter Quetschungen der Bauchorgane den Retroperitonealraum genau zu besichtigen und auf einen etwaigen Ergu?
hinter dem Peritoneum zu achten. -Durch Naht des Duodenums wurde der Fall ohne Dr?nage geheilt. Wegen Narbenstenose mu?te
sp?ter eine G.E. angelegt werden. 相似文献
995.
996.
van den Hurk JA; Hendriks W; van de Pol DJ; Oerlemans F; Jaissle G; Ruther K; Kohler K; Hartmann J; Zrenner E; van Bokhoven H; Wieringa B; Ropers HH; Cremers FP 《Human molecular genetics》1997,6(6):851-858
Choroideremia (CHM) is an X-linked progressive eye disorder which results
from defects in the human Rab escort protein-1 (REP-1) gene. A gene
targeting approach was used to disrupt the mouse chm/rep-1 gene. Chimeric
males transmitted the mutated gene to their carrier daughters but,
surprisingly, these heterozygous females had neither affected male nor
carrier female offspring. The targeted rep-1 allele was detectable,
however, in male as well as female blastocyst stage embryos isolated from a
heterozygous mother. Thus, disruption of the rep-1 gene gives rise to
lethality in male embryos; in female embryos it is only lethal if the
mutation is of maternal origin. This observation can be explained by
preferential inactivation of the paternal X chromosome in murine
extraembryonic membranes suggesting that expression of the rep-1 gene is
essential in these tissues. In both heterozygous females and chimeras the
rep-1 mutation causes photoreceptor cell degeneration. Consequently,
conditional rescue of the embryonic lethal phenotype of the rep-1 mutation
may provide a faithful mouse model for choroideremia.
相似文献
997.
Physicochemical characterization of porcine pararotavirus and detection of virus and viral antibodies using cell culture immunofluorescence. 总被引:6,自引:10,他引:6 下载免费PDF全文
A cell culture immunofluorescence (CCIF) assay was optimized for detection of porcine pararotavirus (group C rotavirus) in intestinal contents. The greatest viral infectivity was observed when MA104 cells (5 days after subculturing) were rinsed and refed in serum-free medium before inoculation, pancreatin was added to the inocula, and the inocula were centrifuged onto the cells. Gentamicin treatment of pararotavirus samples to reduce bacterial contamination also reduced the viral infectivity of these samples for MA104 cells. An indirect CCIF assay was used to determine the prevalence of pararotavirus and rotavirus antibodies in pig sera. In pigs from four herds, pararotavirus antibodies were detected in 100% (68 of 68) of adults and 59% (24 of 41) of weanling pigs, while 86% (24 of 28) of nursing pigs from 12 herds had pararotavirus antibodies. The physicochemical properties of pararotavirus were examined and compared with those of group A rotaviruses by using the CCIF assay to quantitate in vitro changes in viral infectivity. Pararotavirus was inactivated (greater than or equal to 99% reduction in titer) by heating to 56 degrees C for 30 min, was slightly labile at pH 3 (16 to 34% reduction in titer), and was stable at pH 5 (0 to 17% reduction in titer) and in either (3 to 19% reduction in titer). One group A rotavirus (Gottfried strain) was stable at 56 degrees C (0% reduction in titer), whereas the OSU strain of group A rotavirus was inactivated at this temperature (99% reduction in titer). 相似文献
998.
999.
1000.
Diagnosis of disseminated histoplasmosis by detection of Histoplasma capsulatum antigen in serum and urine specimens 总被引:24,自引:0,他引:24
The diagnosis of Histoplasma capsulatum infection by serologic testing for the presence of antibodies is limited by a high rate of false positive and false negative results and by the requirement that the patient have a normal immune response. We have developed a radioimmunoassay for the detection of H. capsulatum antigen in urine and serum specimens. Antigenuria was noted in 20 of 22 episodes of disseminated histoplasmosis that occurred in 16 patients, in 6 of 32 patients with self-limited infection, in 2 of 32 patients with cavitary histoplasmosis, and in 4 of 8 patients with a sarcoid-like illness caused by H. capsulatum. The detection of antigen in urine was reproducible in 38 of 41 (93 percent) retests of specimens. H. capsulatum antigen was also detected in the serum during 11 of the 22 episodes of disseminated histoplasmosis, in none of the 12 episodes of other types of histoplasmosis in patients with antigenuria, in 1 of the 33 patients with histoplasmosis who lacked the urinary antigen, and in none of the 50 controls. Antigenemia and antigenuria decreased after initiation of antifungal therapy and recurred in patients who had a relapse. We conclude that this radioimmunoassay for H. capsulatum antigen represents a useful new method for the rapid diagnosis of disseminated histoplasmosis. 相似文献