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71.
A life-threatening infection: Fournier's gangrene   总被引:1,自引:0,他引:1  
Fournier's gangrene is a life-threateningdisorder in which infection of the perineum andscrotum spreads along fascial planes, causingsoft tissue necrosis. If urgent surgery isdelayed, the disease will soon result in septicshock, multiorgan failure, and death. In thisstudy, we present 21 patients with Fournier'sgangrene who were treated in period between1994 and 2001. Patients' charts were reviewedretrospectively and are discussed in the lightof literature.All patients received aggressive surgicaldebridment. Penicillin or Ceftriaxone,aminoglicoside and metronidazole wereadministered intravenously. Of the 21 patients,5 had scrotal carbuncle, 1 had urethralstricture, 1 had chronic indwelling urethralcatheterization, 2 had perirectal abscess, and1 had hemorrhoidectomy. In eleven patients wecouldn't identify any cause. Twelve patientshad diabetes mellitus, and two had chronicalcoholism. Escherichia coli was isolatedin 12 purulent tissue cultures, and Bacteroides fragilis in eight. Seventeenpatients survived, whereas four died.Fournier's gangrene is considered a surgicalemergency. Early surgical intervention isessential, as the gangrene can spread rapidlyat rates reaching 2 mm per hour. So thatFournier's gangrene is an abrupt, rapidlyprogressive, gangrenous infection of theexternal genitalia and perineum and is a realurologic emergency.  相似文献   
72.
Background: 1% of breast cancers occur in men.The etiology is obscure. An elevated BMI has been postulated to be a cause. Methods: All male breast cancer patients operated from January 1990 to May 2001 were retrospectively reviewed. Relation between BMI and male breast cancer was examined. Results: 43 males underwent breast surgery for breast cancer during this period. 3 patients were excluded from the study because of other risk factors for breast cancer.The average BMI of 40 patients was 26.54 kg/m2, which is mildly above the level for normal weight. Conclusions: Excessive adipose tissue may increase risk of male breast cancer.  相似文献   
73.
L-carnitine in experimental retinal ischemia-reperfusion injury   总被引:1,自引:0,他引:1  
The effect of L-carnitine on retinal ischemia-reperfusion injury was evaluated in guinea pigs. 90 min of pressure-induced retinal ischemia followed by 24 h of reperfusion was established in both eyes of 2 groups of animals receiving either L-carnitine (100 mg/kg repeated in 5 doses) or saline intraperitoneally. After enucleation of all the eyes, including those of a control group, malonyldialdehyde (MDA) levels and the thickness of the retinal tissue were measured in 3 groups. The mean MDA value and the tissue thickness of the L-carnitine-treated group were statistically insignificant versus the control group (p > 0.05 and p > 0.05, respectively). However, these values were significantly different in the group receiving saline versus the control group and that receiving L-carnitine (p < 0.001, p < 0.001 and p < 0.001, p < 0.001 respectively). L-Carnitine might be an alternative drug for ischemia-reperfusion injury of the retina.  相似文献   
74.
This experimental study was performed to investigate the role of ischemia–reperfusion injury on retinal nitric oxide activity and to determine whether octreotide, the synthetic analogue of natural somatostatin, modifies the nitric oxide activity during retinal ischemia–reperfusion in a quinea pig model. Three groups of seven pigmented male quinea pigs were formed; Control, Ischemia and the Ischemia/Octreotide groups. 90 minutes of pressure-induced retinal ischemia and 24 h of reperfusion were established in the ischemia and ischemia/octreotide groups. Saline for the ischemia group and 50 g/kg of octreotide for the ischemia/octreotide group were administered intraperitoneally five times with 6-h intervals. At the end of the reperfusion period both eyes of the animals of the three groups were enucleated. One eye of each animal was randomly selected for biochemical assay and the other for histopathological analysis. Retinal nitrate levels were measured and histopathological changes were evaluated in the groups. The mean retinal nitrate levels of the control, ischemia and ischemia/octreotide groups were 157.6±25.2, 106.4±20.1 and 96.4±17.7 mol/l, respectively. Nitrate levels decreased significantly both in the ischemia (p<0.01) and ischemia/octreotide (p<0.01) groups versus control. In the ischemia group, retinal histopathological changes, which were different from the control group, were prominent edema, polymorphonucleated leukocytes infiltration and vacuolated spaces in the inner retina. No significant change was observed in the histopathological specimens of the ischemia/octreotide group. Significant increase in the thickness of the inner plexiform layer of the retina of the ischemia group was observed versus the control and ischemia/octreotide groups (p<0.01 and p<0.01, respectively).The thickness of the inner plexiform layer of the retina of the ischemia/octreotide group did not change versus the control group. It was concluded that nitric oxide activity decreased during retinal ischemia–reperfusion and, although octreotide prevented the histopathological damage, it could not ameliorate the nitric oxide activity of the retina.This study was presented in part at the 23rd Congress of the European Society of Ophthalmology.  相似文献   
75.
Electrooxidation of beta-estradiol was investigated using a glassy carbon electrode (GCE) by cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The statistical analysis of the linear relationships between concentration and peak current permits the quantitation of beta-estradiol by both CV and DPV in the concentration range of 4 x 10(-5)-10(-3) M with enough precision and accuracy. A mechanism was proposed about the electrooxidation of this substance. The methods were applied to a tablet form and a transdermal therapeutic system (TTS) of this drug. The results were statistically compared with those of official high performance liquid chromatography (HPLC) method and the differences were found as insignificant.  相似文献   
76.
The effects of L-arginine, the precursor in the synthesis of nitric oxide (NO), were investigated in the penile bulb isolated from saline (control) or lipopolysaccharide (20 mg/kg, i.p.)-treated rats. Four consecutive concentration-response curves for L-arginine were made at hourly intervals with the penile bulb. L-arginine (10(7)-10(-3) M) elicited a concentration- and time-dependent relaxation response in the control group. The NO synthase (NOS) inhibitors, N(G)-methyl-L-arginine (L-NMMA) and aminoguanidine, guanylate cyclase inhibitor, 1-H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ) and protein synthesis inhibitor, cycloheximide, inhibited L-arginine-induced relaxation. In the lipopolysaccharide-group, L-arginine produced a pronounced non-time-dependent relaxation at the first concentration-response curve, which was not different from the fourth response of the control group. This response was also inhibited by aminoguanidine. These results show that L-arginine induced NO-mediated relaxation and suggest the presence of a biochemical pathway converting L-arginine to NO, which is probably an inducible type in the penile bulb.  相似文献   
77.
The development of resistance to current antifungal therapeutics drives the search for effective new agents. The fact that some acetophenone-derived Mannich bases had shown antifungal activities in our previous studies led us to design and synthesize acetophenone-derived bis Mannich bases, B1-B5, bis(beta-aroylethyl)methylamine hydrochlorides, to evaluate their antifungal activity. These bis Mannich bases were then converted to the corresponding piperidinols, C1-C5, which are structural isomers of bis derivatives, 3-aroyl-4-aryl-1-methyl-4-piperidinol hydrochlorides, to see alterations in biological activity. A stability study of B1 and Cl was also carried out to estimate whether they alkylate the thiols. All compounds studied have shown antifungal activity, especially against dermatophytes (Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans, and Microsporum canis), in the concentration range studied (2-128 microng/ml). The activity was especially apparent against T. tonsurans. All compounds had at least equal antifungal activity compared with the reference compound amphotericin-B against T. tonsurans. Bis Mannich bases were generally found to be more potent compounds than their structural isomer piperidinols. The results of our stability studies suggest that thiol alkylation may contribute to the antifungal activity of the Mannich bases synthesized. Even though all compounds showed antifungal activity against dermatophytes, bis Mannich bases B1, B2, B4, and B5 appear to have potential for developing novel antifungal agents against dermatophytes.  相似文献   
78.
We have developed a host-mediated assay system for detection of the transforming activity of chemical carcinogens on peritoneal macrophages. Directly, as well as indirectly acting carcinogenic substances, administered intraperitoneally to NMRI mice, could be examined in this way. Resident macrophages were recovered by peritoneal lavage from treated and untreated mice and cultured in soft agar. After 5-6 days the normal and transformed cells could be distinguished. Statistical analysis comparing cells from musk xylene- or musk tibetene-treated animals with those from control mice proved that the test is positive. Musk xylene and musk tibetene revealed a cell-transforming potential that showed a dose-dependent response in our host-mediated assay system. We have succeeded in establishing permanent cell lines from mice treated with musk xylene, or musk tibetene. The oncogenicity of these cell lines was tested in athymic nu/nu mice. Animals injected subcutaneously with these cells (1 x 10(6) cells at each side of the neck) developed tumors at the injection sites within 3 weeks of treatment. The experimental data reported here lead to the conclusion that musk xylene, as well as musk tibetene, have carcinogenic activity. In contrast to the negative results for mutagenicity and genotoxicity, a non-genotoxic mechanism for the carcinogenicity of musk xylene and musk tibetene must be considered.  相似文献   
79.
All-trans retinoic acid (ATRA) is used in the treatment of acute promyelocytic leukemia. Because ATRA has effects (increase in apoptosis, suppression of bcl-2), it has also been used for the treatment of other French-American-British (FAB) subtypes of acute myelogenous leukemia (AML). To find out the in vivo and in vitro effects of ATRA in AML, we analyzed 37 patients with de novo AML. Twenty-seven patients received ATRA before remission-induction (RI) treatment (ATRA group). Results were compared to a control group (10 patients) that received induction without ATRA during the same time period. Bone marrow or peripheral blood samples were collected from all patients on d 0 and 4. The immunphenotype, myeloperoxidase (MPO), reaction and the efflux uptake of rhodamine 123 (Rh123) were analyzed on myeloblasts in these samples. In the myeloblasts from patients treated with ATRA, the uptake of Rh123 was increased significantly (p=0.026) from d 0 to d 4, and all other parameters remained unaltered. ATRA administration increased the complete remission (CR) rate (88%, 22/25 vs 55%, 5/9) significantly (p=0.042). Logistic regression analysis revealed that ATRA administration was the important factor in CR, among other potential factors including age, white blood count, bcl-2 expression, and the uptake and efflux of Rh123 (p=0.05). Estimated disease-free survival and overall survival were similar between these two groups (43% vs 37.5% and 51.2% vs 37.5%, respectively). In conclusion, ATRA treatment prior to RI treatment may improve the CR rate in patients with de novo AML, which seems to be related to its beneficial effect on multidrug resistance.  相似文献   
80.
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