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741.
Pancreatic abscess: predictive value of early abdominal CT 总被引:1,自引:0,他引:1
Vernacchia FS; Jeffrey RB Jr; Federle MP; Grendell JH; Laing FC; Wing VW; Wall SD 《Radiology》1987,162(2):435-438
The value of a recently reported grading system of early abdominal computed tomography (CT) for predicting development of pancreatic abscess in patients with acute pancreatitis was reassessed. When the previously described CT grading system was used in another patient population, it did not demonstrate the same degree of prognostic value of baseline CT. In this series pancreatic abscess occurred in only eight of 29 patients (28%) with grade E CT scans (with grade E representing the most severe involvement), compared with 60% in the previous series. Of 44 patients with either grade D or E baseline CT scans, abscesses developed in only 30%, with a minimum clinical follow-up of 3 months. A second grading system, which used a semiquantitative analysis of the degree of peripancreatic inflammation (a "CT severity score"), also did not strongly correlate with the future risk of abscess, The authors conclude that early abdominal CT should be performed selectively in patients with acute pancreatitis and reserved for patients who are either diagnostic dilemmas or who fail to respond to supportive treatment and have clinically suspected surgical complications such as pancreatic abscess. 相似文献
742.
J W Keller W H Knospe M Raney C M Huguley L Johnson A A Bartolucci G A Omura 《Cancer》1986,58(6):1185-1192
Patients with untreated chronic lymphocytic leukemia (CLL) received protocol treatment with 6 months of chlorambucil (CB) (30 mg/M2) and prednisone (P) (80 mg/d X 5) every 2 weeks. Complete and partial responders (CR, PR) were then randomized to consolidation with six more courses of CB and P or to four courses of cytosine arabinoside (25 mg/M2 every 12 hours X 8, subcutaneously) and cyclophosphamide (25 mg/M2 every 12 hours X 8, orally) every three weeks. Of the 178 eligible patients entered, 138 (78%) were evaluable for induction therapy which produced a 22% hematologic CR and an overall response rate (CR + PR) of 74%. Eighty-two patients received adequate consolidation, at the end of which 43 were in CR. No difference was seen in response or survival between the two consolidation treatments. Responders had longer survival than nonresponders (P = 0.0001) even when a 6-month "guarantee time" was excluded, but there was no survival difference between CR and PR. Thus, intermittent CB and P is a well-tolerated, useful therapy for CLL but the addition of cyclophosphamide and cytosine arabinoside does not improve results. 相似文献
743.
Urinary mutagenicity as a biomarker in workers exposed to benzidine: correlation with urinary metabolites and urothelial DNA adducts 总被引:1,自引:1,他引:1
DeMarini DM; Brooks LR; Bhatnagar VK; Hayes RB; Eischen BT; Shelton ML; Zenser TV; Talaska G; Kashyap SK; Dosemeci M; Kashyap R; Parikh DJ; Lakshmi V; Hsu F; Davis BB; Jaeger M; Rothman N 《Carcinogenesis》1997,18(5):981-988
Urinary mutagenicity has been used in occupational and epidemiological
studies for over two decades as a cost-effective, general biomarker of
exposure to genotoxic agents. However, few studies have compared urinary
mutagenicity to additional biomarkers determined among low- and
high-exposed groups. To address this issue, we evaluated the relationship
between urinary mutagenicity and other types of biomarkers in a
cross-sectional study involving 15 workers exposed to the urinary bladder
carcinogen benzidine (BZ, high exposure), 15 workers exposed to BZ-dyes
(low exposure), and 13 unexposed controls in Ahmedabad, India. Urinary
organics were extracted by C18/methanol and evaluated for mutagenicity in
the presence of S9 in the Salmonella strain YG1024, which is a frameshift
strain that overproduces acetyltransferase. The results were compared to
biomarker data reported recently from the same urine samples (Rothman et
al., Proc. Natl Acad. Sci. USA, 93, 5084- 5089, 1996) that included a
metabolite biomarker (the sum of the urinary levels of BZ +
N-acetylbenzidine + N,N'-diacetylbenzidine) and a DNA adduct biomarker [a
presumptive N-(3'-phosphodeoxyguanosin-8-yl)- N'-acetylbenzidine (C8dG-ABZ)
DNA adduct in exfoliated urothelial cells]. The mean +/- SE urinary
mutagenicity (revertants/micromol of creatinine) of the low-exposure
(BZ-dye) workers was 8.2 +/- 2.4, which was significantly different from
the mean of the controls (2.8 +/- 0.7, P = 0.04) as was that of the mean of
the high-exposure (BZ) workers (123.2 +/- 26.1, P < 0.0001). Urinary
mutagenicity showed strong, positive correlations with urinary metabolites
(r = 0.88, P < 0.0001) and the level of the presumptive C8dG-ABZ
urothelial DNA adduct (r = 0.59, P = 0.0006). A strong association was
found between tobacco use (bidi smoking) and urinary mutagenicity among the
controls (r = 0.68, P = 0.01) but not among the exposed workers (r = 0.18,
P = 0.11). This study confirms the ability of a biomarker such as urinary
mutagenicity to detect low-dose exposures, identify additional genotoxic
exposures among the controls, and correlate strongly with urinary
metabolites and DNA adducts in the target tissue (urinary bladder
epithelia) in humans.
相似文献
744.
A pilot study of the human chorionic gonadotrophin test for ovarian hyperandrogenism 总被引:1,自引:4,他引:1
A controlled clinical study was designed to investigate the value of human
chorionic gonadotrophin (HCG) challenge as a test for functional ovarian
hyperandrogenism. Dexamethasone administration was followed by 5000 IU HCG
and blood samples for steroid hormone assay were obtained 0, 8, 16, and 24
h thereafter. Study subjects were normal women (n = 13); women with
functional ovarian hyperandrogenism, defined by androgen excess,
amenorrhoea and an increased 17-hydroxyprogesterone response to nafarelin
(n = 6); and normal men (n = 4). The responses of 17-hydroxyprogesterone,
androstenedione and testosterone to HCG in women with functional ovarian
hyperandrogenism were significantly greater than in normal women. However,
the 17-hydroxyprogesterone response to HCG in functional ovarian
hyperandrogenism was significantly lower after HCG than after nafarelin.
The oestradiol response was also significantly lower after HCG than
nafarelin, although oestradiol concentration more than doubled in normal
women as well as in women with functional ovarian hyperandrogenism. The
responses to HCG confirm that functional ovarian hyperandrogenism
abnormalities are luteinizing hormone (LH)-dependent. Therefore, the 17-
hydroxyprogesterone response to HCG could represent a useful test for the
diagnosis of ovarian hyperandrogenism. The lower 17- hydroxyprogesterone
response to HCG than to nafarelin in functional ovarian hyperandrogenism
suggests that a follicle-stimulating hormone (FSH)-responsive factor
modulates thecal 17-hydroxyprogesterone secretion. The oestradiol response
to HCG is consistent with HCG directly stimulating the oestradiol secretion
by thecal cells.
相似文献
745.
The 185delAG BRCA1 mutation originated before the dispersion of Jews in the diaspora and is not limited to Ashkenazim 总被引:4,自引:0,他引:4
Bar-Sade RB; Kruglikova A; Modan B; Gak E; Hirsh-Yechezkel G; Theodor L; Novikov I; Gershoni-Baruch R; Risel S; Papa MZ; Ben-Baruch G; Friedman E 《Human molecular genetics》1998,7(5):801-805
The 185delAG mutation in BRCA1 is detected in Ashkenazi Jews both in
familial breast and ovarian cancer and in the general population. All
tested Ashkenazi mutation carriers share the same allelic pattern at the
BRCA1 locus. Our previous study showed that this 'Ashkenazi' mutation also
occurs in Iraqi Jews with a similar allelic pattern. We extended our
analysis to other non-Ashkenazi subsets: 354 of Moroccan origin, 200
Yemenites and 150 Iranian Jews. Heteroduplex analysis complemented by
direct DNA sequencing of abnormally migrating bands were employed. Four of
Moroccan origin (1. 1%) and none of the Yemenites or Iranians was a carrier
of the 185delAG mutation. BRCA1 allelic patterns were determined for four
of these individuals and for 12 additional non-Ashkenazi 185delAG mutation
carriers who had breast/ovarian cancer. Six non-Ashkenazi individuals
shared the common 'Ashkenazi haplotype', four had a closely related
pattern, and the rest ( n = 6) displayed a distinct BRCA1 allelic pattern.
We conclude that the 185delAG BRCA1 mutation occurs in some non-Ashkenazi
populations at rates comparable with that of Ashkenazim. The majority of
Jewish 185delAG mutation carriers have a common allelic pattern, supporting
the founder effect notion, but dating the mutation's origin to an earlier
date than currently estimated. However, the different allelic pattern at
the BRCA1 locus even in some Jewish mutation carriers, might suggest that
the mutation arose independently.
相似文献
746.
747.
Aim: The purpose of this experiment was to investigate the role of extracellular signal‐regulated kinase 1/2 (ERK1/2) signalling in the contraction‐induced increase in muscle FA uptake. Methods: Male Wistar rats (n = 41) were randomly assigned to either a resting or stimulated group. Within each group, animals were randomly assigned to receive PD‐98059, an inhibitor of MAP/ERK kinase 1/2 (MEK1/2), a kinase upstream of ERK1/2 and perfused with 550 μm palmitate, [14C]palmitate, 7 mm glucose, and no insulin. In the stimulated group, electrical stimulation (ES) of supramaximal trains of 100 ms was delivered every 2 s for 20 min. Results: ERK1/2 phosphorylation was increased by 50% (P < 0.05) during ES but the contraction‐induced increase was prevented by the addition of PD‐98059. Glucose uptake increased by 3.6‐fold (P < 0.05) from rest to ES in muscle perfused without PD‐98059 and was not affected by the addition of PD‐98059 either at rest (P > 0.05) or during ES (P > 0.05). For a matched palmitate delivery, ES increased palmitate uptake by 35% (P < 0.05). PD‐98059 had no effect on palmitate uptake at rest but completely abolished the increase in palmitate uptake during ES. Plasma membrane FAT/CD36 protein content was increased by 38% during ES (P < 0.05) but the contraction‐induced increase was prevented by the addition of PD‐98059. AMPK activity was increased by ES (P < 0.05) but was unaffected by PD‐98059. Conclusion: These results show for the first time that the increase in FA uptake and in plasma membrane FAT/CD36 protein content is mediated, at least in part, by the ERK1/2 signalling pathway during muscle contraction. 相似文献
748.
Permissive recognition of immunodominant determinants of the retinal S- antigen in different rat strains, primates and humans 总被引:1,自引:0,他引:1
Fukushima A; Lai JC; Chanaud NP rd; Shiloach J; Whitcup SM; Nussenblatt RB; Gery I 《International immunology》1997,9(1):169-177
The majority of antigenic peptides exhibit restriction in their interaction
with the MHC molecules on antigen-presenting cells of different haplotypes.
Certain peptides, however, are "permissive': they bind strongly to
different MHC molecules and are selected as the immunodominant epitopes by
animals using these MHC gene products. Here we show for the first time that
several peptides from four regions of the sequence of human S-antigen
(H-SAg), a retinal-specific protein, demonstrate high levels of
permissiveness. Each of these peptides was found to be immunodominant in at
least some of four inbred rat strains and five cynomolgus monkeys,
immunized with whole H-SAg. Moreover, some of these peptides were
recognized by lymphocytes from four normal controls and four patients with
uveitis who responded against the H-SAg molecule. On the other hand, the
permissive peptides stimulated marginal or no response in cultures of Lewis
rats injected with adjuvant alone, or rat and human cell lines specific to
other antigens, thus demonstrating that these peptides do not carry any
non-specific mitogenic activity. One peptide, 29, which was found
immunodominant in the monkeys, the uveitis patients and Lewis rats, is
highly immunopathogenic in this rat strain. No good correlation between
immunodominance and immunopathogenicity was found with other H-SAg
peptides. The finding of cross-species permissiveness among peptides of
H-SAg and similar observations with myelin proteins suggest that
permissiveness could be quite prevalent among peptides of immunopathogenic
antigens.
相似文献
749.
Evaluation of the NCCLS extended-spectrum beta-lactamase confirmation methods for Escherichia coli with isolates collected during Project ICARE 总被引:1,自引:0,他引:1 下载免费PDF全文
Tenover FC Raney PM Williams PP Rasheed JK Biddle JW Oliver A Fridkin SK Jevitt L McGowan JE;Project ICARE 《Journal of clinical microbiology》2003,41(7):3142-3146
To determine whether confirmatory tests for extended-spectrum beta-lactamase (ESBL) production in Escherichia coli are necessary, we selected 131 E. coli isolates that met the National Committee for Clinical Laboratory Standards (NCCLS) screening criteria for potential ESBL production from the Project ICARE (Intensive Care Antimicrobial Resistance Epidemiology) strain collection. For all 131 isolates, the broth microdilution (BMD) MIC of at least one extended-spectrum cephalosporin was >/=2 micro g/ml. For 21 of 131 (16%) isolates, the ESBL confirmatory test was positive; i.e., the BMD MICs of ceftazidime or cefotaxime decreased by >/=3 doubling dilutions in the presence of clavulanic acid (CA) or the disk diffusion zone diameters increased by >/=5 mm around ceftazidime or cefotaxime disks in the presence of CA. All 21 isolates were shown by PCR to contain at least one of the genes bla(TEM), bla(SHV), and bla(OXA), and in isoelectric focusing (IEF) tests, all isolates demonstrated at least one beta-lactamase band consistent with a TEM, SHV, or OXA enzyme. Of the 21 isolates, 3 showed a CA effect for cefotaxime by BMD but not by disk diffusion testing. A total of 59 (45%) of the 131 isolates demonstrated decreased susceptibility to cefpodoxime alone (MIC = 2 to 4 micro g/ml), and none had a positive ESBL confirmatory test result. These were classified as false positives according to ESBL screen test results. For the remaining 51 (39%) isolates, the cefpodoxime MICs ranged from 16 to >128 micro g/ml and the MICs for the other extended-spectrum cephalosporins were highly variable. All 51 isolates gave negative ESBL confirmatory test results. Most showed IEF profiles consistent with production of both a TEM and an AmpC beta-lactamase, and representative isolates of several phenotypic groups showed changes in porin profiles; these 51 isolates were considered true negatives. In all, only 16% of 131 E. coli isolates identified as potential ESBL producers by the current NCCLS screening criteria were confirmed as ESBL producers. Thus, changing the interpretation of extended-spectrum cephalosporins and aztreonam results from the susceptible to the resistant category without confirming the presence of an ESBL phenotype would lead to a large percentage of false resistance results and is not recommended. However, by increasing the cefpodoxime MIC screening breakpoint to >/=8 micro g/ml, 45% of the false-positive results could be eliminated. NCCLS has incorporated this change in the cefpodoxime screening breakpoint in its recent documents. 相似文献
750.