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401.
BACKGROUND: The need for mechanical cleansing of the bowel before elective colorectal surgery is generally accepted. There are various methods for preparation in use today, but it is still controversial which of them is superior to the others. AIM: To determine whether there is a significant difference in postoperative infectious wound complications rate between the traditional bowel preparation and oral lavage with the osmotic agent Mannitol. METHODS: A retrospective study from January 1997 to June 2000 was performed. Patients who underwent elective surgery for colorectal carcinomas were divided into two groups according to the method of colonic cleansing that was used. The traditional bowel preparation was performed with 30.0 cc Castor oil given per os in the day before the operation and three soap enemas (Group I). Patients from the other group (Group II) were given 500 cc 10% Mannitol in the day before the operation. RESULTS: There were 154 patients in Group I and 36 patients in Group II. Infectious wound complications developed in 26 patients from Group I versus 13 patients from Group II. The difference was statistically significant (16.9% vs. 36.1%, p < 0.01). The differences in the incidence of anastomotic leaks and mortality rate between the two groups were without statistical significance. CONCLUSION: The use of Mannitol is associated with increase in the postoperative infectious wound complications and therefore should be avoided as colonic cleansing method in elective colorectal surgery.  相似文献   
402.
Chronic dislocation of the temporomandibular jaw (TMJ) can result from lax joint ligaments and parafunctioning joints; it can also be a consequence of a systemic connective tissue disorder. The authors report a case of hypermobile joint syndrome in combination with mitral valve prolapse. The case was managed by osteosynthesis using modified titanium plate.  相似文献   
403.
1背景 新生儿听力普遍筛查(universal neonatal hearing screening,UNHS)是早期发现听力损失的有效手段.一些发达国家,如美国,澳大利亚和英国等,已经或正在建立新生儿听力普遍筛查项目.有许多研究报道了开展该项目可能获得的效益[1~3],但是关于该项目在发展中国家可行性的报道却很少[4,5].  相似文献   
404.
We describe two adolescent girls with acute lymphoblastic leukemia (ALL) whose leukemia cells were near-haploid. Their lymphoblasts stained in a block pattern with periodic acid Schiff and had "common ALL" surface markers confirmed by indirect immunofluorescence. Each patient had two populations of blasts, one near-haploid and one hyperdiploid, which was an exact doubling of the near-haploid karyotype. The first patient had a predominant population of cells with 26 chromosomes and a few with 52, while the second had a predominance of cells with 56 and a minority with 28. Flow cytometric analysis of DNA content initially detected the minor near-haploid population in the second patient, which was confirmed later by cytogenetic review of the marrow sample. In addition to our two patients, only four patients have been reported with near-haploid ALL. Of these six, five were girls, five were adolescents, and five had short survivals (median, 10 mo). All six had disomy of chromosome 21 with or without disomy for chromosomes 10, 14, 18, or X (four patients each). Thus, near-haploid ALL may represent a unique subgroup of ALL with a poor prognosis. To detect these and other possible subgroups, we have included cytogenetic analysis and flow cytometric analysis of DNA content in our initial evaluation of patients with ALL.  相似文献   
405.

Objectives:

The purpose of this study was to determine the potential of high-resolution ultrasonography for the detection of temporomandibular joint (TMJ) changes in children with juvenile idiopathic arthritis (JIA).

Methods:

We investigated prospectively 20 children (17 female and 3 male; mean age 11.06 years, standard deviation 3.43 years) with TMJ disorders caused by JIA, over a period of 16 months. Using a 12 MHz array transducer, four images in each TMJ (160 images) were acquired. Each image was analysed with regard to five different aspects (condylar erosion, thickness of the condylar disc, synovial thickness, joint effusion and enlargement of the intra-articular space).

Results:

Diagnosis of JIA was ensured for every child and involvement of the TMJ was proven by MRI. Overall 287 changes (35.9%) were detected by using high-resolution ultrasonography. On 124 images (77.5%) condylar erosions were diagnosed; on 55 images (34.4%) synovial thickness was abnormal; on 48 images (30%) we could see higher thickness of the condylar disc; on 40 images (25%) irregularities of the bony surface were detected; and on 20 images (12.5%) we found joint effusion.

Conclusion:

High-resolution ultrasonography could be a sufficient diagnostic method, especially for the detection of condylar involvement in children with JIA, even if not all parts of the TMJ are visible for ultrasonography. High-resolution ultrasonography is a valuable tool in particular situations: (i) when MRI examination is not available; (ii) when children fear MRI examination; (iii) in more advanced stages of JIA; and (iv) for monitoring the progression of TMJ involvement and response of therapy.  相似文献   
406.

Background

There is paucity of data on Lyme disease in India. A seroprevalence study of B burgdorferi infection was carried out in North-Eastern states of India to assess the same.

Methods

Sera from 500 individuals of North-Eastern states of India were tested for IgG antibody by enzyme linked immunosorbent assay using commercial kits containing recombinant antigen.

Result

Out of 500 persons, 65 (13%) were positive for B burgdorferi specific lgG Females showed higher positivity rate as compared to males (15.86% vs 10.95%). Higher prevalence rate was observed in the age group of 15-30 years in both sexes (11.48% in male and 18.69% in female). Arunachal Pradesh showed higher seroprevalence rate (17.8%) as compared to other North-Eastern states (8.46-9.6%).

Conclusion

Seropositivity to B burgdorferi suggests infection by the organism and presence of Lyme disease in these areas. Further population and vector biology studies are required to find out the exact species involved in transmission of the organism.Key Words: Lyme Disease, Seroprevalence, Borrelia burgdorferi  相似文献   
407.
Background: There is paucity of data on Lyme disease in India. A seroprevalence study of B burgdorferi infection was carried out in North-Eastern states of India to assess the same.  相似文献   
408.
Excessive environmental vibrations can have deleterious effects on animal health and experimental results, but they remain poorly understood in the animal laboratory setting. The aims of this study were to characterize train-associated vibration in a rodent vivarium and to assess the effects of this vibration on the reproductive success and fecal corticosterone metabolite levels of mice. An instrumented cage, featuring a high-sensitivity microphone and accelerometer, was used to characterize the vibrations and sound in a vivarium that is near an active railroad. The vibrations caused by the passing trains are 3 times larger in amplitude than are the ambient facility vibrations, whereas most of the associated sound was below the audible range for mice. Mice housed in the room closest to the railroad tracks had pregnancy rates that were 50% to 60% lower than those of mice of the same strains but bred in other parts of the facility. To verify the effect of the train vibrations, we used a custom-built electromagnetic shaker to simulate the train-induced vibrations in a controlled environment. Fecal pellets were collected from male and female mice that were exposed to the simulated vibrations and from unexposed control animals. Analysis of the fecal samples revealed that vibrations similar to those produced by a passing train can increase the levels of fecal corticosterone metabolites in female mice. These increases warrant attention to the effects of vibration on mice and, consequently, on reproduction and experimental outcomes.Abbreviations: FCM, fecal corticosterone metabolites; LPSC, Linus Pauling Science CenterTo reduce confounding variables, many laboratory conditions are standardized (light cycle duration, air quality, temperature, and relative humidity) to a narrowly defined acceptable range.10 Environmental sound and vibration in animal vivaria are two potentially overlooked factors that could have detrimental impacts on the ability of researchers to produce consistent experimental results. The Guide for the Care and Use of Laboratory Animals suggests that activities that produce sound and vibration in animal rooms should be minimized, citing the potential for animal distress and altered research results.10 The effect of sound on the physiology and behavior of mice is widely recognized and can range from mild distress to reduced reproductive efficiency and audiogenic seizures in some strains of mice.25,36 The hearing range of mice is speculated to range from 1 to 100 kHz in contrast to human hearing, which is between 20 Hz and 20 kHz.7,13 It is important to note, however, that the hearing range of mice is a subject of debate because of an inability to accurately determine the true lower and upper bounds of mouse hearing.13 Some researchers indicate that the lower frequency limit for the hearing of mice is at 2.3 kHz, whereas others state that the greatest hearing sensitivity in mice occurs between 12 to 24 kHz.7,37 The disparity between the hearing range of mice and that of humans has led to the speculation that humans may overestimate how loud or bothersome certain sounds are to laboratory mice.26Whereas the hearing ranges of laboratory mice have been quantified,7,13,37 there are no published data on a specific perception threshold for vibration in mice. However, information pertaining to the pathologic or physiologic effects seen with whole-body vibration at several amplitudes and frequencies has been reported.35,16,27,34,35 In rats, whole-body vibration increased plasma corticosterone and brain serotonin levels at 0.4 × g and 20 Hz.1 Increased adrenal weight and decreased gastric emptying time were observed at 2.0 to 2.4 × g and 5 to 15 Hz.28,30 In mice, whole-body vibration decreased adipogenesis,27 and increased bone formation at 0.1 to 0.3 m/s2 and up to 90 Hz,27,34,35 suggesting that vibration at those levels is biologically significant. In terms of reproduction as well as deformities, vibration has been reported to increase rates of fetal resorption and cleft palate and has been linked to cannablism.14,16Vibration in the form of ‘shaker stress’ has been reported as a stress model, in which customized cages are mounted on a shaking platform with a 2- to 3-cm stroke at 60 to 150 cycles per minute.3,4,18 Shaker stress is a pain-free stimulus that has been shown to cause reproducible changes in blood pressure, heart rate, sympathetic activity, and stress hormone secretion.6,18Despite the well-documented evidence of stress induction due to whole-body vibration in rodents, little information exists regarding the effects of environmental vibration on laboratory mice in standard housing conditions. One study20 investigated the vibrations produced by various heavy machinery during building construction and compared them with the resonant frequencies of three anatomic locations in several species, including mice, rats, and humans. The authors concluded that particular vibration frequency ranges are more likely to affect rats and mice as compared with humans.20 More research is needed to encompass the various vibration scenarios that occur in the laboratory setting—only then can standards be formulated to control and mitigate this biologic stressor.Laboratory animal vivaria are constructed to suit the needs of the institution in regard to proximity to other research facilities, campus land-use planning, and land restrictions. As a result, laboratory animal housing can be located near subways, trains, or highways, all of which might transmit vibrations at magnitudes and frequencies that cause stress in rodents. As a case in point, the Laboratory Animal Resources Center at Oregon State University is located approximately 30 m from an active railroad track. On average, 4 trains of various lengths pass the building each afternoon.The closest animal room to the train tracks developed problems with abnormally high rates of cannibalism or neglect of pups. After investigating other potential causes such as temperature variations, light–dark cycles, and diet, we hypothesized that the vibrations from the train were a significant factor. The reproductive success of the same set of mice improved after they were moved from a flat wire rack to a single motor-ventilated rack. The ventilated racks hold cages in place with a cage clip and therefore might decrease cage-to-rack vibration. In addition, ventilated racks are much heavier than are wire racks and have an air intake and exhaust system that generates its own constant minor background vibrations; these factors may contribute to a dampening or partial masking of the potentially more startling short-duration, intense train-induced vibrations. Similar high rates of preweaning mortality have not occurred at the other main rodent housing facility on campus, the Linus Pauling Science Center (LPSC), which is a state-of-the-art science facility that was constructed in 2011 and lies approximately 490 m away from the railroad tracks. The differences in mouse reproductive success between the facilities and rack types prompted us to investigate the effects of environmental vibration.Vibrations and sound are disturbances that travel through a medium. Vibrations often move through a solid medium, whereas sound passes through a gaseous or liquid one, such as air or water. The disturbances caused by vibrations and sound can often be represented by a wave model. Waves oscillate with a specific frequency and have particular amplitudes, which change as the waves propagate from the source. For this study, it is important to know the frequency and amplitude of the waves that are measured to categorize their effects. Certain wave frequencies and amplitudes may be more detrimental to the health of the mice. The majority of the energy produced by trains moving on the ground surface is conveyed by Rayleigh waves.23,29 Such vibration waves usually have a frequency between 2 to 80 Hz, frequencies that can disturb people.23,29 Regarding sound, the energy generated at the source travels through the air as a longitudinal or pressure wave.24 The ears of humans and mice are designed to process a broad frequency range, and a decibel scale is used to indicate sound pressure in a concise manner.The specific goal of the current study was to characterize the effects of train-associated vibration and sound on laboratory mice housed on flat racks. During the preliminary observational part of the study, the vibrations from trains were characterized in terms of magnitude and frequency. In addition, the reproductive success of mice housed in a vibration-prone room in the vivarium was monitored. To further explore the effects of train-induced vibration more objectively, the second part of the study exposed a set of mice to environmental vibration in a controlled setting. To create controlled vibrations, an electromagnetic shaker was designed and constructed to induce vibrations similar to those produced by the trains passing the vivarium. The mice were monitored by measuring fecal corticosterone metabolites (FCM). We hypothesized that mice exposed to train vibrations have elevated FCM.  相似文献   
409.
We treated 24 children and adolescents with stage III or IV lymphoblastic non-Hodgkin's lymphoma, using a protocol designed for patients with poor-prognosis acute lymphoblastic leukemia (ALL). Early therapy consisted of teniposide plus cytarabine administered before and immediately after prednisone, vincristine, and asparaginase. The two- drug combination was also given intermittently with continuous 6- mercaptopurine and methotrexate during the first year of continuation chemotherapy. Periodic intrathecal methotrexate and delayed cranial irradiation were used to prevent central nervous system involvement. Anthracycline compounds, alkylating agents, high-dose methotrexate, and involved-field irradiation were not used in any phase of treatment. Twenty-two (96%) of the 23 evaluable patients achieved complete remission. With a median follow-up of 2 1/2 years, only four patients have relapsed; the remainder have been disease-free for eight months to more than five years. The projected four-year continuous complete remission rate is 73% for all patients and 79% for the 19 with mediastinal involvement at diagnosis. These results demonstrate that use of teniposide plus cytarabine with an otherwise conventional plan of ALL therapy is an effective approach to the treatment of childhood lymphoblastic lymphoma.  相似文献   
410.
Apparent mineralocorticoid excess (AME) is a severe form of hypertension that is caused by impaired activity of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), which converts biologically active cortisol into inactive cortisone. Mutations in HSD11B2 result in cortisol-induced activation of mineralocorticoid receptors and cause hypertension with hypokalemia, metabolic alkalosis, and suppressed circulating renin and aldosterone concentrations. This study uncovered the first patient with AME who was described in the literature, identified the genetic defect in HSD11B2, and provided evidence for a novel mechanism of reduced 11beta-HSD2 activity. This study identified a cluster of amino acids (335 to 339) in the C-terminus of 11beta-HSD2 that are essential for protein stability. The cluster includes Tyr(338), which is mutated in the index patient, and Arg(335) and Arg(337), previously reported to be mutated in hypertensive patients. It was found that wild-type 11beta-HSD2 is a relatively stable enzyme with a half-life of 21 h, whereas that of Tyr(338)His and Arg(337)His was 3 and 4 h, respectively. Enzymatic activity of Tyr(338)His was partially retained at 26 degrees C or in the presence of the chemical chaperones glycerol and dexamethasone, indicating thermodynamic instability and misfolding. The results provide evidence that the degradation of both misfolded mutant Tyr(338)His and wild-type 11beta-HSD2 occurs through the proteasome pathway. Therefore, impaired 11beta-HSD2 protein stability rather than reduced gene expression or loss of catalytic activity seems to be responsible for the development of hypertension in some individuals with AME.  相似文献   
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