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1.
2.
This study investigates how the option for new‐concept part‐time (NPT) employment influences the ability of mothers of preschool children working in professional occupations to successfully integrate work and family responsibilities. Female NPT professionals (n = 279) and female full‐time (FT) professionals (n = 250) were compared. The NPT group reported 20 fewer weekly work hours and about $18,000 less estimated annual household income than the FT group. They allocated this additional time primarily to caring for and nurturing their dependent children. They also reported less job‐related travel, unnecessary work, and work‐to‐family conflict, as well as greater work‐family success, childcare satisfaction, and family success. However, NPT mothers reported a more traditional division of labor in household responsibilities and less career opportunity and work success. Implications are presented and discussed.  相似文献   
3.
Advances in our knowledge of the biology of skeletal stem cells, together with an increased understanding of the regeneration of normal tissue offer exciting new therapeutic approaches in musculoskeletal repair. Skeletal stem cells from various adult tissues such as bone marrow can be identified and isolated based on their expression of a panel of markers associated with smooth muscle cells, pericytes and endothelial cells. Thus, skeletal stem cell-like populations within bone marrow may share a common perivascular stem cell niche within the microvascular network. To date, the environmental niche that nurtures and maintains the stromal stem cell at different anatomical sites remains poorly understood. However, an understanding of the osteogenic and perivascular niches will inform identification of the key growth factors, matrix constituents and physiological conditions that will enhance the ex vivo amplification and differentiation of osteogenic stem cells to mimic native tissue critical for tissue repair. This review will examine skeletal stem cell biology, the advances in our understanding of the skeletal and perivascular niche and interactions therein and the opportunities to harness that knowledge for musculoskeletal regeneration.  相似文献   
4.
Intrauterine growth restriction is associated with increased risk of adult cardiorenal diseases. Small birth weight females are more likely to experience complications during their own pregnancy, including pregnancy-induced hypertension, preeclampsia, and gestational diabetes. We determined whether the physiological demand of pregnancy predisposes growth-restricted females to cardiovascular and renal dysfunction later in life. Late gestation bilateral uterine vessel ligation was performed in Wistar-Kyoto rats. At 4 months, restricted and control female offspring were mated with normal males and delivered naturally (ex-pregnant). Regardless of maternal birth weight, at 13 months, ex-pregnant females developed elevated mean arterial pressure (indwelling tail-artery catheter; +6 mm Hg), reduced effective renal blood flow ((14)C-PAH clearance; -23%), and increased renal vascular resistance (+27%) compared with age-matched virgins. Glomerular filtration rate ((3)H-inulin clearance) was not different across groups. This adverse cardiorenal phenotype in ex-pregnant females was associated with elevated systemic (+57%) and altered intrarenal components of the renin-angiotensin system. After pregnancy at 13 months, coronary flow (Langendorff preparation) was halved in restricted females compared with controls, and together with reduced NO excretion, this may increase susceptibility to additional lifestyle challenges. Our results have implications for aging females who have been pregnant, suggesting long-term cardiovascular and renal alterations, with additional consequences for females who were small at birth.  相似文献   
5.

Background

It is believed that many postoperative patient readmissions can be curbed via optimization of a patient's discharge from hospital, but little is known about how surgeons make the decision to discharge a patient. This study explored the criteria that surgeons preferentially value in their discharge decision-making process.

Materials and methods

All surgical faculty and residents at a U.S. academic medical center were surveyed about the relative importance of specific criteria regularly used to make a discharge decision. Demographic and professional information was collected about each surgeon as well. A Kruskal–Wallis and Fisher's exact test were used to describe one-way analysis of variance between groupings of surgeons. Ordered logit regressions were used to analyze variations across multiple subgroups. Factor analysis was used to further characterize statistically relevant groupings of criteria.

Results

In total, 88 (49%) of the invited surgeons responded to the survey. Respondents reported statistically less reliance on common Laboratory tests and Patient demographics when making discharge decisions preferring Vital signs, Perioperative factors, and Functional criteria. Surgeon-specific factors that influenced discharge criteria preferences included years of clinical education and gender. Factor analysis further identified subtle variations in preferences for specific criteria groupings based on clinical education, gender, and race.

Conclusions

Surgeons use a wide range of clinical data when making discharge decisions. Typical measures of patient condition also appear to be used heterogeneously with a preference for binary rather than continuous measures. Further understanding the nature of these preferences may suggest novel ways of presenting discharge-relevant information to clinical decision makers to optimize discharge outcomes.  相似文献   
6.
In several species and in many vascular beds, ultrastructural studies describe close contact sites between the endothelium and smooth muscle of <~20nm. Such sites are thought to facilitate the local action of signaling molecules and/or the passage of current, as metabolic and electrical coupling conduits between the arterial endothelium and smooth muscle. These sites have the potential for bidirectional communication between the endothelium and smooth muscle, as a key pathway for coordinating vascular function. The aim of this brief review is to summarize the literature on the ultrastructural anatomy and distribution of key components of MECC sites in arteries. In addition to their traditional role of facilitating electrical coupling between the two cell layers, data on the role of MECC sites in arteries, as signaling microdomains involving a spatial localization of channels, receptors and calcium stores are highlighted. Diversity in the density and specific characteristics of MECC sites as signaling microdomains suggests considerable potential for functional diversity within and between arteries in health and disease.  相似文献   
7.
Surgical training has changed significantly in the United Kingdom in last decade. A simulator for practising various tendon repairing techniques is presented. It has been designed for the use of junior trainees in Hand surgery dealing with the routine hand trauma cases and can be assembled quickly and cheaply.  相似文献   
8.
The contribution of endothelium-derived hyperpolarizing factor (EDHF), nitric oxide (NO) and a prostanoid (PG) to endothelium-dependent hyperpolarization and relaxation were assessed in coronary and mammary arteries of guinea-pigs by integration of the responses evoked during discrete applications of acetylcholine (ACh). The results of this integration approach were compared with those using traditional peak analysis methods. N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM) and indomethacin (1 microM), alone or in combination, were without effect on peak hyperpolarizations or relaxations while they markedly reduced the integrated responses in both arteries. Integrated responses attributed to NO and PG were larger than those attributed to EDHF in the coronary artery (at 2 microM ACh, hyperpolarization (mV s): NO, 4200+/-91; PG, 5046+/-157; EDHF, 1532+/-94; relaxation (mN s mm(-1)): NO, 2488+/-122; PG, 2234+/-96; EDHF, 802+/-54). Integrated responses attributed to NO, PG and EDHF were similar in the mammary artery (at 2 microM ACh, hyperpolarization: NO, 347+/-69; PG, 217+/-49; EDHF, 310+/-63; relaxation: NO, 462+/-94; PG, 456+/-144; EDHF, 458+/-40). Gilbenclamide (1 microM) all but abolished the hyperpolarization attributable to NO and PG but not EDHF in both arteries allowing assessment of the role of the hyperpolarization in relaxation. Gilbenclamide was without effect on the integrated relaxation due to NO but significantly reduced the relaxation associated with PG in the two arteries. In conclusion, integration of the responses enabled a more complete assessment of the contribution of EDHF, NO and PG to endothelium-dependent responses, which were strikingly different in the two arteries. There is commonality in the role of hyperpolarization in relaxation in both arteries: EDHF-dependent relaxation is strongly dependent on hyperpolarization; hyperpolarization plays an important role in PG relaxation, whereas it has a small facilitatory role in NO-dependent relaxation.  相似文献   
9.
The spleen is an important organ for the host response to systemic bacterial infections. Many cell types and cell surface receptors have been shown to play role in the capture and control of bacteria, yet these are often studied individually and a coherent picture has yet to emerge of how various phagocytes collaborate to control bacterial infection. We analyzed the cellular distribution of Listeria monocytogenes (LM) in situ during the early phase of infection. Using an immunohistochemistry approach, five distinct phagocyte populations contained LM after i.v. challenge and accounted for roughly all bacterial signal in tissue sections. Our analysis showed that LM was initially captured by a wide range of phagocytes in the marginal zone, where the growth of LM appeared to be controlled. The cellular distribution of LM within phagocyte populations changed rapidly during the first few hours, decreasing in marginal zone macrophages and transiently increasing in CD11c+ DC. After 4–6 h LM was transported to the periarteriolar lymphoid sheath where the infective foci developed and LM grew exponentially.  相似文献   
10.

Ethnopharmacological relevance

Bacopa monnieri (Brahmi) provides traditional cognitive treatments possibly reflecting improved cerebral hemodynamics. Little is known about the cardiovascular actions of Brahmi. We sought to assess its effects on blood pressure and on isolated arteries, thus providing insights to clinical applications.

Materials and methods

Intravenous Brahmi (20-60 mg/kg) was tested on arterial blood pressure and heart rate of anaesthetized rats. In vitro vasorelaxation was assessed in arteries, with and without blockers of nitric oxide synthase (L-NAME), cyclooxygenase (indomethacin), and mechanical de-endothelialisation. The effects of Brahmi on Ca2+ influx and release from stores were investigated.

Results

Intravenous Brahmi extract (20-60 mg/kg) decreased systolic and diastolic pressures without affecting heart rate. Brahmi evoked relaxation in isolated arteries in order of potency: basilar (IC50 = 102 ± 16 μg/ml) > mesenteric (171 ± 31) > aortae (213 ± 68) > renal (IC50 = 375 ± 51) > tail artery (494 ± 93) > femoral arteries (>1000 μg/ml). Two saponins, bacoside A3 and bacopaside II, had similar vasodilator actions (IC50 = 8.3 ± 1.7 and 19.5 ± 6.3 μM). In aortae, without endothelium or in L-NAME (10-4 M), Brahmi was less potent (IC50 = 213 ± 68 to 2170 ± 664 and 1192 ± 167 μg/ml, respectively); indomethacin (10-5 M) was ineffective. In tail artery, Brahmi inhibited K+-depolarization induced Ca2+ influx and Ca2+ release from the sarcoplasmic reticulum by phenylephrine (10-5 M) or caffeine (20 mM).

Conclusions

Brahmi reduces blood pressure partly via releasing nitric oxide from the endothelium, with additional actions on vascular smooth muscle Ca2+ homeostasis. Some Brahmi ingredients could be efficacious antihypertensives and the vasodilation could account for some medicinal actions.  相似文献   
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