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51.
The aim of this study was to evaluate the influence of laser photobiomodulation in cutaneous healing of rats under a hyperlipidic diet. Forty-eight Wistar Albinus rats, weaned, received standard diet (SD) or hyperlipidic diet (HD) for 20 weeks. The groups were divided into SD rats and HD rats, SD-irradiated rats (LSD), and HD-irradiated rats (LHD). Standard cutaneous wound (1 cm2) was created on the dorsum of each rat. The irradiation started immediately after surgery and every 48 h for 7 or 14 days (λ660 nm, 40 mW, 6 J/cm2, ? 0,04 cm2, CW), when they were killed under deep anesthesia. The specimens were removed, routinely processed, stained with hematoxylin/eosin (H/E), and evaluated by light microscopy. Rats fed with hyperlipidic diet had greater intensity in the inflammatory process and prolonged hyperemia. At day 7, the intensity of inflammation was reduced in LSD and LHD groups when compared to their control groups, SD (p?=?0.002) and HD (p?=?0.02). There was an increase in fibroblast proliferation and collagen deposition, especially in the LHD group. At day 14, the HD group presented more intensive hyperemia than the SD group. It can be concluded that the hyperlipidic diet modified the inflammation pattern in wound healing and that laser light has a positive biomodulative effect on the healing process only in early stages.  相似文献   
52.
BACKGROUND: Xenograft rejection is associated with vascular inflammation, thrombocytopenia and the accelerated consumption of coagulation factors. Primary biological incompatibilities of the xenograft in the regulation of clotting appear to amplify pathological processes associated with rejection. The functional incompatibility of porcine von Willebrand factor (vWF) expressed within the xenograft vasculature may heighten interactions with the primate platelet receptor GPIb, hence augmenting formation of platelet microthrombi and vascular injury. Here, we address the functional impact of O-linked glycosylation of the vWF A1 domain on primate platelet activation. METHODS: Recombinant human or porcine vWF A1-domains were transiently over-expressed in COS-7 cells as FLAG-tagged fusion protein, linked to plasma membranes via GPI anchors. O-linked glycosylation was blocked by the addition of phenyl-alpha-GalNAc2 to cultures. Expressed vWF-A1 domains were characterized utilizing cytofluometric- and Western blot analyses. RESULTS: Cytofluometric analysis confirmed equivalent levels of human and porcine vWF A1-domain expression irrespective of the levels of O-linked glycosylation. Differential glycosylation patterns of vWF-A1 under these conditions were confirmed by Western blot analyses. Native porcine vWF A1-domains had enhanced human platelet activation potential when compared with human recombinant vWF A1. However, the loss of O-linked glycosylation abolished differences in aggregatory responses between human and porcine vWF A1 domains. CONCLUSIONS: Various degrees of O-linked glycosylation of vWF-A1-domains modulate levels of functional interaction with platelet receptor GPIb and consequent platelet aggregation responses in vitro. These data may have implications for outcomes of xenotransplantation. We speculate that alterations in glycosylation of vWF and other adhesion proteins associated with the targeting of the alpha1,3-Gal-epitope in mutant swine may have salutatory effects on the primate platelet activation observed in these xenografts.  相似文献   
53.
OBJECTIVE: To evaluate the surgical outcome, complications and benefits of laparoscopic double promonto-fixation for patients with pelvic prolapse. METHODS: Women with genito-urinary prolapse underwent a transperitoneal placement of a 100% polyester mesh on the anterior vaginal wall and a posterior mesh on the levator ani muscle. Both of these were anchored to the sacral promontory. A TVT was placed simultaneously in patients who had concurrent stress urinary incontinence. RESULTS: A total of 363 patients were operated upon between 1996 and 2002. Their mean age was 63 (range 35-78), average follow-up was 14.6 months, the mean operating time was 97 minutes. There were 8 conversions due to anesthetic or surgical difficulties. Follow up was done by a postal questionnaire and physical examination at 6 months and then yearly. 96% were satisfied with the results of their operation and no patients complained of sexual dysfunction. There was a 4% recurrence rate of prolapse, 3 vaginal erosions, 2 urinary retentions that required TVT section, 1 bowel incarcerations, 1 spondylitis and 2 mesh infection. CONCLUSIONS: Laparoscopic promonto-fixation is feasible and highly effective technique that offers good long-term results with complication rates similar to open surgery, with the added benefits of minimally invasive surgery.  相似文献   
54.
Wang X  Rasmussen T  Pahar B  Poonia B  Alvarez X  Lackner AA  Veazey RS 《Blood》2007,109(3):1174-1181
Rapid, profound, and selective depletion of memory CD4+ T cells has now been confirmed to occur in simian immunodeficiency virus (SIV)-infected adult macaques and human immunodeficiency virus (HIV)-infected humans. Within days of infection, marked depletion of memory CD4+ T cells occurs primarily in mucosal tissues, the major reservoir for memory CD4+ T cells in adults. However, HIV infection in neonates often results in higher viral loads and rapid disease progression, despite the paucity of memory CD4+ T cells in the peripheral blood. Here, we examined the immunophenotype of CD4+ T cells in normal and SIV-infected neonatal macaques to determine the distribution of naive and memory T-cell subsets in tissues. We demonstrate that, similar to adults, neonates have abundant memory CD4+ T cells in the intestinal tract and spleen and that these are selectively infected and depleted in primary SIV infection. Within 12 days of SIV infection, activated (CD69+), central memory (CD95+CD28+) CD4+ T cells are marked and persistently depleted in the intestine and other tissues of neonates compared with controls. The results in dicate that "activated" central memory CD4+ T cells are the major target for early SIV infection and CD4+ T cell depletion in neonatal macaques.  相似文献   
55.
In an effort to bypass the adverse secondary effects attributed to the traditional therapeutic approaches used to treat skin disorders (such as atopic dermatitis), alternative antimicrobials have recently been suggested. One such antimicrobial is chitosan, owing to the already proved biological properties associated with its use. However, the influence of abiotic factors on such activities warrants evaluation. This research effort assessed the antimicrobial activity of chitosan upon skin microorganisms (Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli) in vitro when subject to a combination of different abiotic factors such as pH, ionic strength, organic acids and free fatty acids. Free fatty acids, ionic strength and pH significantly affected chitosan's capability of reducing the viable numbers of S. aureus. This antimicrobial action was potentiated in the presence of palmitic acid and a lower ionic strength (0.2% NaCl), while a higher ionic strength (0.4% NaCl) favored chitosan's action upon the reduction of viable numbers of S. epidermidis and E. coli. Although further studies are needed, these preliminary results advocate that chitosan can in the future be potentially considered as an antimicrobial of choice when handling symptoms associated with atopic dermatitis.  相似文献   
56.
Background Granuloma annulare (GA) is limited in most cases to isolated lesions, but more widespread generalized forms can be observed. In both cases, the treatment remains highly challenging. Isolated case reports suggested the interest of treating GA with a pulsed dye laser (PDL). Objective To evaluate the PDL in treating GA. Materials and methods Retrospective multicentre study. Each patient should have at least two lesions of GA including at least one that remained untreated to serve as a control. The evaluation was performed on an Investigator Global Assessment for each lesion as compared with baseline. Results Thirteen patients (five with localized GA and eight with generalized GA) with a total of 59 lesions have been treated with a maximum of three PDL sessions. Sixteen lesions (27.1%) achieved >50% of clearing (14% of lesions for generalized GA and 56.2% for localized GA). Transient hyperpigmentation and crusting were observed in 59% and 86% of lesions respectively. The median follow‐up was 6 months (2–12) and 10 lesions (all in generalized GA) recurred after initial clearing. Conclusion Generalized GA showed weak improvement after treatment with a high recurrence rate. Only localized forms showed notable improvement in a more than half of treated lesions. Thus, PDL could be proposed as an alternative approach, but only for localized forms of GA.  相似文献   
57.
Background:  There is a lack of prospective studies investigating contact sensitization in patients with chronic leg ulcers.
Objectives:  To determine the frequency of contact sensitization in patients with chronic leg ulcers using a special series of patch tests and to determine whether the number of sensitizations was correlated with the duration of the chronic leg ulcers.
Patients/methods:  Multicentre study carried out in patients with chronic leg ulcers; patch tests with the European baseline series and with an additional 34 individual allergens or mixes and 3 commercial products.
Results:  Of the 423 patients (301 women, 122 men, mean age 68.5 years) with chronic leg ulcers, 308 (73%) had at least one positive patch test with 3.65 positive patch tests per patient. The main allergens were Myroxylon pereirae (41%), fragrance mix I (26.5%), antiseptics (20%), and corticosteroids (8%). The number of positive tests per patient was not correlated with the cause of ulcer but was increased with the duration of the ulcer with a statistical difference between the group of the <1 year compared with the group >10 years duration.
Conclusions:  From this large prospective multicentre study, polysensitization is frequent in patients with chronic leg ulcers, increasing with the duration of the ulcer. We propose avoidance of topical antiseptics and ointments containing perfumes in patients with chronic leg ulcers and an updated patch test series for investigating these patients.  相似文献   
58.
Mitochondrial dysfunction might play a role in the pathogenesis of liver damage in erythropoietic protoporphyria (EPP). Changes in mitochondrial respiratory chain activities were evaluated in the Fech(m1pas)/Fech(m1pas) mouse model for EPP. Mice from different strains congenic for the same ferrochelatase germline mutation manifest variable degrees of hepatobiliary injury. Protoporphyric animals bred into the C57BL/6J background showed a higher degree of hepatomegaly and liver damage as well as higher protoporphyrin (PP) accumulation than those bred into the SJL/J and BALB/cJ backgrounds. Whereas mitochondrial respiratory chain activities remained unchanged in the liver of protoporphyric mice C57BL/6J, they were increased in protoporphyric mice from both SJL/J and BALB/cJ backgrounds, when compared to wild-type animals. Mitochondrial respiratory chain activities were increased in Hep G2 cell line after accumulation of PP following addition of aminolevulinic acid. As a direct effect of these elevated mitochondrial activities, in both hepatic cells from mutant mouse strains and Hep G2 cells, adenosine 5'-triphosphate (ATP) levels significantly increased as the intracellular PP concentration was reduced. These results indicate that PP modifies intracellular ATP requirements as well as hepatic mitochondrial respiratory chain enzymatic activities and further suggest that an increase of these activities may provide a certain degree of protection against liver damage in protoporphyric mice.  相似文献   
59.
Background Longevity, combined with a higher prevalence of obesity, particularly visceral obesity, has been associated with an increased risk of cardiovascular diseases. Insulin resistance (IR) is an important link between visceral obesity and cardiovascular diseases. An important association has been found between sagittal abdominal diameter, visceral obesity and IR. The objective of this study is to evaluate sagittal abdominal diameter as a marker of visceral obesity and correlate it with IR in older primary health care patients. Methods A cross-sectional study was performed with 389 patients over 60 years of age (70.6 ± 6.9), of whom 74% were female. Their clinical, anthropometric and metabolic profiles were assessed and their fasting serum insulin level was used to calculate the homeostasis model assessment insulin resistance (HOMA-IR). Sagittal abdominal diameter was measured in the supine position at the midpoint between the iliac crest and the last rib with abdominal calipers. Results Sagittal abdominal diameter was significantly correlated with anthropometric measures of general and visceral obesity and with HOMA-IR in both genders. There was no change in the association between sagittal abdominal diameter and HOMA-IR after adjusting for age, sex, diabetes and hypertension. Conclusion It is feasible to use sagittal abdominal diameter in older primary care patients as a tool to evaluate visceral obesity, which is an indicator of cardiovascular risk.  相似文献   
60.
Objectives To evaluate the relevance of obesity and abdominal obesity in the prevalence of cardiovascular disease (CVD), diabetes mellitus, hyperlipidaemia and hypertension in primary care patients and to ascertain whether waist circumference (WC) measurement should be included in routine clinical practice in addition to body mass index (BMI). Methods As part of the IDEA study, primary care physicians from Spain recruited patients aged 18–80 years. WC and BMI and the presence of CVD, diabetes mellitus, hyperlipidaemia and hypertension were recorded. Finally, 17 980 were analysed. An age‐related increase in adiposity was observed. Overall 33% were obese by BMI, and 51% of subjects presented abdominal obesity by the National Cholesterol Education Program Adult Treatment Panel III (NCEP‐ATPIII) (WC > 102 cm for men and > 88 cm for women). Although there was a correlation between BMI and WC, they presented different distribution patterns. Women, but not men, with a high level of education, professional activity and smoking were associated with a lower WC. Abdominal obesity was significantly associated with CVD. Some subjects with abdominal obesity but lean by BMI, showed an increased prevalence of CVD and diabetes. Furthermore, abdominal obesity was strongly associated with dyslipidaemia and hypertension. Conclusions Half of the primary care patients studied showed abdominal obesity as measured by WC, whereas one‐third was obese by BMI. Abdominal obesity was strongly associated with CVD and diabetes, even in patients lean by BMI. WC should be included in the routine clinical practice in addition to BMI.  相似文献   
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