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41.
AIM:To evaluate the efficacy and mechanism of action of NCB-02,a standardized Curcumin preparation,against 2,4-dinitrochlorobenzene(DNCB)-induced ulcerative colitis in rats.METHODS:Ulcerative colitis was induced in male rats by sensitizing with topical application of DNCB in acetone for 14 d and intra-colonol challenge with DNCB on day 15.A separate group of animals with vehicle treatment in similar fashion served as control group.Colitis rats were divided into different groups and treated with NCB-02 at doses of 25,50 and 100 mg/kg b.wt p.o.for 10 d.Sulfasalazine at a dose of 100 mg/kg b.wt for 10 d served as a reference group.On day 10 after respective assigned treatment,all the animals were euthanized and the length of the colon,weight of entire colon and distal 8 cm of the colon were recorded.The distal part of the colon was immediately observed under a stereomicroscope and the degree of damage was scored.Further distal 8 cm of the colon was subject to the determination of colonic myeloperoxidase(MPO),lipid peroxidation(LPO)and alkaline phosphatase (ALP)activities.A small piece of the sample from distal colon of each animal was fixed in 10% neutral buffered formalin and embedded in paraffin wax and sectioned for immunohistochemical examination of NFκ-B and iNOS expression.RESULTS:NCB-02 showed a dose dependent protection against DNCB-induced alteration in colon length and weight.NCB-02 treatment also showed a dose dependent protection against the elevated levels of MPO,LPO and ALP,induced by DNCB.NCB-02 demonstrated a significant effect at a dose of 100 mg/kg b.wt.,which was almost equipotent to 100 mg/kg b.wt.of sulfasalazine.Treatment with sulfasalazine and curcumin at a dose of 100 mg/kg b.wt.inhibited the DNCB-induced overexpression of NFκ-B and iNOS in the colon.CONCLUSION:Curcumin treatment ameliorates colonic damage in DNCB-induced colitic rats,an effect associated with an improvement in intestinal oxidative stress and downregulation of colonic NFκ-B and iNOS expression.  相似文献   
42.

Background

Hospitals have a critically important role in the management of mass causality incidents (MCI), yet there is little information to assist emergency planners. A significantly limiting factor of a hospital''s capability to treat those affected is its surgical capacity. We therefore intended to provide data about the duration and predictors of life saving operations.

Methods

The data of 20,815 predominantly blunt trauma patients recorded in the Trauma Registry of the German-Trauma-Society was retrospectively analyzed to calculate the duration of life-saving operations as well as their predictors. Inclusion criteria were an ISS ≥ 16 and the performance of relevant ICPM-coded procedures within 6 h of admission.

Results

From 1,228 patients fulfilling the inclusion criteria 1,793 operations could be identified as life-saving operations. Acute injuries to the abdomen accounted for 54.1% followed by head injuries (26.3%), pelvic injuries (11.5%), thoracic injuries (5.0%) and major amputations (3.1%). The mean cut to suture time was 130 min (IQR 65-165 min). Logistic regression revealed 8 variables associated with an emergency operation: AIS of abdomen ≥ 3 (OR 4,00), ISS ≥ 35 (OR 2,94), hemoglobin level ≤ 8 mg/dL (OR 1,40), pulse rate on hospital admission < 40 or > 120/min (OR 1,39), blood pressure on hospital admission < 90 mmHg (OR 1,35), prehospital infusion volume ≥ 2000 ml (OR 1,34), GCS ≤ 8 (OR 1,32) and anisocoria (OR 1,28) on-scene.

Conclusions

The mean operation time of 130 min calculated for emergency life-saving surgical operations provides a realistic guideline for the prospective treatment capacity which can be estimated and projected into an actual incident admission capacity. Knowledge of predictive factors for life-saving emergency operations helps to identify those patients that need most urgent operative treatment in case of blunt MCI.  相似文献   
43.

Background and purpose:

Vascular tolerance to nitroglycerin (GTN) may be caused by impaired GTN bioactivation due to inactivation of mitochondrial aldehyde dehydrogenase (ALDH2). As relaxation to GTN is reduced but still sensitive to ALDH2 inhibitors in ascorbate deficiency, we compared the contribution of ALDH2 inactivation to GTN hyposensitivity in ascorbate deficiency and classical in vivo nitrate tolerance.

Experimental approach:

Guinea pigs were fed standard or ascorbate-free diet for 2 weeks. Reversibility was tested by feeding ascorbate-deficient animals standard diet for 1 week. Nitrate tolerance was induced by subcutaneous injection of 50 mg·kg−1 GTN 4 times daily for 3 days. Ascorbate levels were determined in plasma, blood vessels, heart and liver. GTN-induced relaxation was measured as isometric tension of aortic rings; vascular GTN biotransformation was assayed as formation of 1,2-and 1,3-glyceryl dinitrate (GDN).

Key results:

Two weeks of ascorbate deprivation had no effect on relaxation to nitric oxide but reduced the potency of GTN ∼10-fold in a fully reversible manner. GTN-induced relaxation was similarly reduced in nitrate tolerance but not further attenuated by ALDH inhibitors. Nitrate tolerance reduced ascorbate plasma levels without affecting ascorbate in blood vessels, liver and heart. GTN denitration was significantly diminished in nitrate-tolerant and ascorbate-deficient rings. However, while the ∼10-fold preferential 1,2-GDN formation, indicative for active ALDH2, had been retained in ascorbate deficiency, selectivity was largely lost in nitrate tolerance.

Conclusions and implications:

These results indicate that nitrate tolerance is associated with ALDH2 inactivation, whereas ascorbate deficiency possibly results in down-regulation of ALDH2 expression.  相似文献   
44.
Acute spinal cord injury: MR imaging at 1.5 T   总被引:19,自引:0,他引:19  
Thirty-seven magnetic resonance (MR) imaging studies were performed with a 1.5-T magnet and surface coils in 27 patients with suspected spinal cord injuries. Imaging was performed 1 day to 6 weeks after injury. Cord abnormalities were seen with MR in 19 patients, while skeletal and/or ligamentous injuries were seen in 21 (78%). Three types of MR signal patterns were seen in association with cord injuries. Acute intraspinal hemorrhage was seen in five patients with cord injuries and demonstrated decreased signal intensity on T2-weighted images obtained within 24 hours of injury. Cord edema and contusion had high signal intensity on T2-weighted images and were observed in 12 cases with cord injury. Neurologic recovery, determined in 16 patients, was insignificant in patients with intraspinal hemorrhage; however, patients with cord edema or contusion recovered significant neurologic function. MR at 1.5 T is extremely useful in the diagnosis of acute cord injury and also demonstrates potential in predicting neurologic recovery.  相似文献   
45.
Background Melanoma is a tumour with a very variable progression. Whilst some melanomas grow slowly over many years, others can reach several millimetres in thickness in just a few weeks. Since melanoma is a visible superficial tumour, the information obtained from the clinical interview may be of use to calculate the speed of growth of the melanoma. Objective This study aims to assess the growth rate (GR) of melanomas and the association of this GR with various clinical and pathological factors and their usefulness as prognostic markers for localized invasive cutaneous melanomas. Methods The GR of melanomas was calculated as the ratio of tumour thickness to time of development, as obtained from the clinical history (in millimetres per month). Results Applying the GR calculation to patients with a localized melanoma showed a significant association between melanomas with a GR greater than 0.4 mm per month and an age of 65 years or over, male sex, nodular melanoma, tumour thickness, level of invasion, the presence of ulceration and a high mitotic index. As an independent prognostic factor for overall survival, the GR proved to be significant (P = 0.024). Conclusion The GR of localized cutaneous melanomas may be a possible prognostic factor for survival. Additionally, rapid GR is associated with male patients more advanced in age at diagnosis, which suggests the need to assess new strategies for the early detection of these melanomas.  相似文献   
46.
Background Dermatitis artefacta (DA) is defined as all dermatological, self‐inflicted skin lesions, where the patient denies having produced the lesions. Objectives The purpose of this study is to make a single‐centre retrospective clinical review of patients diagnosed as DA of the breast. Materials and methods During a 30‐year period (1976–2006), patients diagnosed as DA of the breast, seen in the Department of Dermatology of the Virgen Macarena Hospital in Seville, were recorded. Clinical and epidemiological features are described. Results A total of 27 women with a mean age of 34.33 years were selected representing 13.43% of the total of DA patients recorded (n = 201) in this period. The most frequent clinical forms were: excoriations (nine patients, 33.33%) and ulcers (nine patients, 33.33%), followed by burns (six patients, 22.22%), blisters (one patient, 3.70%), contact dermatitis (one patient, 3.70%) and haematomas (one patient, 3.70%). Ten of the cases were located exclusively on the breasts, whereas 17 had also other locations such as face in seven cases, arms in five cases, abdomen in five cases and the entire body in two cases. Cutaneous lesions were treated with occlusive bandages using zinc paste or plaster splint when necessary. Conclusion To our knowledge, this is the major series of DA of the breast studied. This complicated psychodermatological condition requires a correct diagnosis, appropriate management and psychiatric assessment.  相似文献   
47.
Measurements of oxygen consumption (VO2) were made during sleep in 10 patients with atopic dermatitis. Two groups of healthy children acted as controls. All subjects were studied in bed in an environmental temperature of 24-26 degrees C, and sleep was confirmed during continuous electroencephalographic monitoring. Mean (SD) values of VO2 in sleeping patients who were not scratching ranged from 4.0 (0.4) to 7.4 (0.7), which was not statistically significantly different from control values which ranged from 3.24 (0.3) to 5.56 (0.4). During scratching (while asleep), which occurred in nine out of 10 patients with atopic dermatitis, the mean values of VO2 ranged from 4.5 (0.04) to 10.4 (2.7), and this was significantly higher than the non-scratching patients and the control values. Scratching during sleep in children with atopic dermatitis is associated with increased VO2.  相似文献   
48.
Organization, expression and polymorphism of the human persyn gene   总被引:13,自引:0,他引:13  
Persyn is a recently identified member of the synuclein family with a distinct pattern of expression during pre- and postnatal development of the mouse peripheral and central nervous systems. As with other synucleins, persyn is believed to be involved in the pathogenesis of human neurodegenerative diseases. However, in contrast to other synucleins, high levels of persyn mRNA expression were also found in advanced breast carcinomas, suggesting an involvement of the encoded protein in breast tumour progression. Here we have used an antibody specific to human persyn to demonstrate that the level of this protein is increased in ageing cerebral cortex and in breast tumours. We cloned, characterized and sequenced the human persyn genomic locus and localized it to the long arm of chromosome 10 in the q23.2-q23.3 region. Sequence information was used to search for specific mutations in the protein coding regions of persyn mRNA and the persyn gene in breast tumours and tumour cell lines. No tumour-specific mutations were found, but two linked polymorphisms in the coding region were detected, both in mRNA and exons III and IV of the gene. These results suggest that development of breast tumours correlates with overexpression of the wild-type persyn protein. Detailed characterization of the human persyn locus is important for further studies of the involvement of persyn in neurodegeneration and malignancy.   相似文献   
49.
Background: Recent studies have shown a substantial decline in caries experience in Australian Army recruits between 1996 and 2002–2003, and in Australian adults between 1987–1988 and 2004–2006. However, studies in children have reported an increasing trend in caries experience between 1998 and 2002. The aim of this study was to investigate caries experience in Australian Army recruits in 2008. Methods: A cross‐sectional study involving 1084 Australian Army recruits was conducted from January to May 2008. Data were obtained from a clinical dental examination with bitewing radiographs, and a questionnaire elicited socio‐demographic data and history on lifetime exposure to fluoridated drinking water. Results: Mean DMFT scores were 3.16, 4.08, 5.16 and 7.11 for recruits aged 17–20, 21–25, 26–30 and 31–35 years, respectively. Recruits with a lifetime exposure to fluoridated drinking water had a mean DMFT of 3.02, while recruits with no exposure had a mean DMFT of 3.87. Conclusions: Caries experience in Australian Army recruits aged 17–25 years increased between 2002–2003 and 2008. Recruits with lifetime exposure to fluoridated drinking water had 25 per cent less caries experience compared with recruits who had no exposure to fluoridated drinking water after adjusting for the effects of age, gender, education and socio‐economic status.  相似文献   
50.
It has been reported that chloroform administered to BDF1 mice by inhalation for 2 years at concentrations of 5, 30 or 90 p.p.m. for 6 h/day, 5 days/week induced an increase in renal cell tumors in male but not female mice exposed to the doses of 30 and 90 p.p.m. A small increase in liver tumors was statistically significant in the female mice at 90 p.p.m. if the incidences of carcinomas and adenomas were combined. Because chloroform is not a DNA reactive mutagen, a 13-week time-course and dose-response study was conducted under conditions of the original bioassay to examine whether regenerative cell proliferation was an underlying mechanism of carcinogenesis. Mice were given bromodeoxyuridine via infusion during the last 3.5 days prior to necropsy to label cells in S-phase. Chloroform induced pathology and regenerative cell proliferation, measured as the labeling index (LI, percentage of cells in S-phase), were assessed microscopically and immunohistochemically. Male mice exposed to 30 and 90 p.p.m. exhibited a dose-dependent increase in regenerating tubules within the renal cortex and up to a 31-fold increase in LI. No renal lesions or increased LI were observed in females. Increased centrilobular to midzonal hepatocyte degeneration and vacuolation and a 7-fold increase over controls in the hepatocyte LI were observed in the female mice at 90 p.p.m. at 13 weeks. Males exhibited similar pathology, but the increase in LI was not sustained. The observed correlations between cytolethality and regenerative cell proliferation with tumor formation supports extensive evidence that chloroform induces cancer via a non- genotoxic-cytotoxic mode of action. A concentration of 5 p.p.m. is the no-observed-adverse-effect level for nephrotoxicity, cell proliferation and cancer. An appropriate safety factor applied to this value is a straightforward approach to cancer risk assessment that is consistent with the mode of action of chloroform.   相似文献   
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