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71.
The aim of the study was to establish the level of the nonspecific nasal responsiveness in a group of workers (N = 84) occupationally exposed to respiratory irritants, and to compare it with its level in healthy subjects (N = 60). Another goal was to study the effect of occupational exposure to irritants, smoking, and atopy on nonspecific nasal responsiveness. The modified method of nonspecific nasal provocation with histamine developed by van Wijk and Dieges (Clin Allerg 17:563–570, 1987) was used. The method was performed by spraying doubling concentrations of histamine (0.03–32 mg/mL), starting with saline, in a cumulative manner into each nostril. The reaction was measured by total nasal resistance (“opening” interruption technique). The result of the test was expressed as provocation concentration of histamine that caused ?75% rise of total nasal resistance compared to its value measured after saline. We found a significantly higher percentage of nasal hyperreactors and a significantly greater nonspecific nasal responsiveness among 65 exposed workers (χ2 = 78.6; p < 0.001, t = ?5.48; p < 0.001, respectively) than in the group of healthy subjects. A significantly (t = 4.25; p < 0.001) increased nonspecific nasal responsiveness was observed during exposure when compared to nonspecific nasal responsiveness assessed after 2 weeks out of exposure, when tested in 19 patients. Higher smoking rate as measured by smoking category (number of cigarettes multiplied with years of smoking) was associated with the lower levels of nonspecific nasal responsiveness. Also, we failed to confirm a relation between atopy and nonspecific nasal responsiveness in a group of workers exposed to irritants. © 1993 Wiley-Liss, Inc.  相似文献   
72.
We present a girl with dermatomyositis, liver cysts and choroid plexus papilloma who was treated and followed for 7 years. Muscle histology revealed an inflammatory muscle disease and similar changes were detected in a brain tumor that was surgically removed at onset. Western blot analysis of the muscle revealed severely reduced calpain-3 protein. She was treated with pulse methylprednisolone treatment (800 mg i.v. for 4 days) followed by oral prednisone treatment (16 mg on alternate day) for 14 months, which improved muscle strength. Moreover, the cystic liver formations disappeared during steroid treatment. This is an unusual association of muscular disorder, steroid-responsive liver cysts, intracranial tumor and secondary calpain-3 deficiency. We speculate that this association is not coincidental, but mediated by an autoimmune attack against an antigen that is shared among the target tissues.  相似文献   
73.
BACKGROUND: Short-term studies established that calcium influences bone accretion during growth. Whether long-term supplementation influences bone accretion in young adults is not known. OBJECTIVE: This study evaluated the long-term effects of calcium supplementation on bone accretion among females from childhood to young adulthood. DESIGN: A 4-y randomized clinical trial recruited 354 females in pubertal stage 2 and optionally was extended for an additional 3 y. The mean dietary calcium intake of the participants over 7 y was approximately 830 mg/d; calcium-supplemented persons received an additional approximately 670 mg/d. Primary outcome variables were distal and proximal radius bone mineral density (BMD), total-body BMD (TBBMD), and metacarpal cortical indexes. RESULTS: Multivariate analyses of the primary outcomes indicated that calcium-supplementation effects vary over time. Follow-up univariate analyses indicated that all primary outcomes were significantly larger in the supplemented group than in the placebo group at the year 4 endpoint. However, at the year 7 endpoint, this effect vanished for TBBMD and distal radius BMD. Longitudinal models for TBBMD and proximal radius BMD, according to the time since menarche, showed a highly significant effect of supplementation during the pubertal growth spurt and a diminishing effect thereafter. Post hoc stratifications by compliance-adjusted total calcium intake and by final stature or metacarpal total cross-sectional area showed that calcium effects depend on compliance and body frame. CONCLUSIONS: Calcium supplementation significantly influenced bone accretion in young females during the pubertal growth spurt. By young adulthood, significant effects remained at metacarpals and at the forearm of tall persons, which indicated that the calcium requirement for growth is associated with skeletal size. These results may be important for both primary prevention of osteoporosis and prevention of bone fragility fractures during growth.  相似文献   
74.
Atopic dermatitis (AD) has cellular immunohistochemical features similar to those of allergic contact dermatitis (ACD) and there is plenty of evidence for T-cell activation in this disease. The involvement of CD30+ T cells in acute stages of atopic dermatitis might establish CD30 as a helpful marker in differentiating those two diseases. Tissue sections from the skin of 12 patients with active atopic dermatitis and 13 with allergic contact (nickel-induced) dermatitis were immunohistochemically analyzed for cell-surface antigens, including CD30, CD3, CD4, and CD45RO. The severity of the disease was graded by the SCORAD clinical scoring system. The analysis of CD30+, CD45RO+, CD3+, and CD4+ cells in the dermis and epidermis showed a much wider range of values and statistically higher median (p<0.01) in the inflammatory infiltrate of acute atopic dermatitis compared with that of allergic contact dermatitis. Our results showed an association of CD30 expression with atopic dermatitis, but not allergic contact dermatitis. CD30 expression in AD might be helpful in histologic differentiation of these disorders and further characterization of atopy patch testing. The results suggested a specific regulatory function of CD30+ T cells in acute AD. Abundant CD45R0+ cells were detected in both AD and ACD lesions.  相似文献   
75.
Korcok J  Dixon SJ  Lo TC  Wilson JX 《Brain research》2003,993(1-2):201-207
Skeletal muscle and brain are major sites of glucose transport and ascorbate (vitamin C) storage. Ascorbate is oxidized to dehydroascorbic acid (DHAA) when used as an enzyme cofactor or free radical scavenger. We evaluated the hypothesis that glucose regulates DHAA uptake and reduction to ascorbate (i.e., recycling) by skeletal muscle cells and cerebral astrocytes. DHAA uptake was inhibited partially by glucose added simultaneously with DHAA. Comparison of wild type L6 skeletal muscle cells with an L6-derived cell line (D23) deficient in facilitative hexose transporter isoform 3 (GLUT3), indicated that both GLUT3 and facilitative hexose transporter isoform 1 (GLUT1) mediate DHAA uptake. Preincubation of muscle cells with glucose inhibited the rates of glucose and DHAA uptake, and decreased the intracellular concentration of ascorbate derived from recycling of DHAA. In contrast, glucose preincubation did not depress GLUT1 protein and activity levels or DHAA recycling in astrocytes. These results establish that glucose downregulates subsequent recycling of DHAA by skeletal muscle cells but not astrocytes.  相似文献   
76.
AIMS AND BACKGROUND: The main characteristic of urothelial bladder cancer is a clear predisposition to recurrence and disease progression. The aim of this study was to assess the possible relationship between cyclooxygenase-2 (COX-2) immunoreactivity in superficial urothelial bladder carcinoma and tumor grade, stage, number of recurrences and clinical disease progression. METHODS: In this prospective study 70 consecutive patients who underwent transurethral resection for superficial urothelial bladder cancer were included. Tumor slides were immunohistochemically stained for COX-2, and COX-2 immunoreactivity in tumor and inflammatory stromal cells was categorized as negative or mildly, moderately or strongly positive. Patients were followed up for 2 years, and during this period the possible association of COX-2 immunoreactivity with tumor stage and grade, number of recurrences and progression of disease was evaluated. RESULTS: COX-2 immunoreactivity in tumor cells was found in 57 (81.4%) patients and did not correlate with tumor grade, stage of disease, number of recurrences, and progression of disease. COX-2 immunoreactivity in inflammatory cells was found in 16 of the 57 patients with COX-2 positive tumors, and was significantly related to the number of recurrences, time to appearance of the first recurrence, and disease progression. CONCLUSIONS: COX-2 immunoreactivity in inflammatory stromal cells adjacent to the COX-2-positive tumor might be useful in clinical practice for selection of patients with a high risk of tumor recurrence and disease progression.  相似文献   
77.
The author describes the method of the suprapubic drainage of the urinary bladder by using the Snaider Urevac of the firm "Zimmer". In 20 patients all urinocultures sampled one and five days after the surgery were negative. The method involves no danger, it is simple and comfortable for the patient in comparison with the transurethral drainage. According to the initial experience of the author, the method of suprapubic drainage could be recommended for a more frequent use in the continuous drainage of the urine in the postoperative period of gynecological patients.  相似文献   
78.
Natural silicate materials, including zeolite clinoptilolite, have been shown to exhibit diverse biological activities and have been used successfully as a vaccine adjuvant and for the treatment of diarrhea. We report a novel use of finely ground clinoptilolite as a potential adjuvant in anticancer therapy. Clinoptilolite treatment of mice and dogs suffering from a variety of tumor types led to improvement in the overall health status, prolongation of life-span, and decrease in tumors size. Local application of clinoptilolite to skin cancers of dogs effectively reduced tumor formation and growth. In addition, toxicology studies on mice and rats demonstrated that the treatment does not have negative effects. In vitro tissue culture studies showed that finely ground clinoptilolite inhibits protein kinase B (c-Akt), induces expression of p21WAF1/CIP1 and p27KIP1 tumor suppressor proteins, and blocks cell growth in several cancer cell lines. These data indicate that clinoptilolite treatment might affect cancer growth by attenuating survival signals and inducing tumor suppressor genes in treated cells.  相似文献   
79.
OBJECTIVE: Tonsillectomy in children may be performed on a day-case basis. To achieve quality anesthesia and successful, fast recovery with minimal morbidity without the use of volatile anesthetic, the choice of drug combination has to be centered on one rapid- and short-acting hypnotic, opioid and non-depolarizing muscle relaxant. The aim of our study was to determine the optimal pediatric induction dose of propofol that by means of alfentanil and reduced-dose rocuronium allows the highest percentage of excellent intubating conditions. METHODS: One hundred and eleven children were randomized in three equal groups and included in prospective, double blind study. Anesthesia was induced with 2.0 (Group A), 2.5 (Group B) or 3.0 mg kg(-1) (Group C) of propofol proceeded by alfentanil (0.02 mg kg(-1)). Muscle relaxation was achieved with reduced-dose rocuronium (1.5x ED(95)) (0.45 mg kg(-1)). The intubating conditions were assessed using the four-point scoring system based on the difficulty of laryngoscopy, presence of vocal cord movement and the intensity of coughing. Neuromuscular transmission was monitored by means of acceleromyography with supramaximal train-of-four stimulation of the ulnar nerve by the frequency of 1Hz. RESULTS: Adequate intubating conditions were achieved in high percentages in all study groups (A = 94%, B = 95%, C = 98%) (P = 0.352). Significant higher differences of excellent and good intubating conditions, attributed to quality of laryngoscopy, movement of the vocal cords and intensity of coughing were observed in Group C (excellent = 94%, good = 4%) (B = excellent 80%, good = 18% and A = excellent 47%, good = 47%) (P = 0.0001). MAP decrease of 12% from the baseline occurred immediately only after 3.0 mg kg(-1) induction dose of propofol (80+/-7 mm Hg; A = 92 +/- 6, B = 88 +/- 9) (P = 0.005). CONCLUSIONS: Induction dose of 2.5 mg kg(-1) of propofol preceded by 0.02 mg kg(-1) of alfentanil in addition to reduced-dose rocuronium (0.45 mg kg(-1)) is the optimal pediatric induction dose of propofol for improving the most excellent intubating conditions without significant hemodynamic changes.  相似文献   
80.
Aim

This study was performed within an international organization (IO), headquartered in Washington, D.C. The employees are facing great risks during their missions abroad, where developing countries are the most common travel destination. The IO conducted a staff road safety survey in 2008 and based a road safety policy on the results of this survey. In 2017, a follow-up survey investigated the impact of the policy implementation. The aim of this study was to investigate the effect of that policy.

Subjects and methods

This study is based on two cross-sectional road safety surveys conducted by the IO’s Staff Road Safety Task Force. The study population consisted of both regular employees and consultants based at country offices (CO) worldwide. The number of reported road traffic crashes and near-crashes (nearly had a crash), as well as road safety behavior, was compared between these two surveys. The analysis was performed from a gender perspective. High-risk countries were identified based on the number of reported road traffic crashes and near-crashes.

Results

Over a period of nine years, the incidence rates had dropped from 1.6 to 0.7 road traffic crashes per 1000 travel days and from 14 to 8.9 near-crashes per 1000 travel days. Seat belt usage had increased from 70% to 80%. There were no major differences between male and female respondents. Developing countries had the highest travel adjusted event rates.

Conclusion

The findings of this study suggest that the policy had a positive impact on road safety among CO staff within the IO.

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