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31.
Eleven of 15 ferrets experimentally infected withBrugia malayi became amicrofilaremic after a brief patency; only four ferrets remained patent after 6 months of infection and two of these ferrets developed a high, persistent microfilaremia. Blastogenic responses of peripheral blood lymphocytes to antigens of microfilariae (mf), assayed in vitro, demonstrated an antigen sensitivity at prepatent, patent and postpatent periods of infection. Lymphocytes from ferrets with high microfilaremia had elevated background responses in culture which were directly correlated with the number of circulating mf. This background response was attributed to antigenic stimulation by mf present in the lymphocyte cultures; addition of mf to cultures of lymphocytes from postpatent ferrets induced responses equivalent to those observed in microfilaremic ferrets. Lymphocyte responses to the mitogen, concanavalin A, did not differ significantly among microfilaremic, amicrofilaremic and uninfected ferrets. Antibody in IgG to antigens of mf measured by ELISA and by immunoblots from SDS-PAGE showed similar patterns of response in ferrets which became amicrofilaremic and in the few ferrets which remained microfilaremic. Prausnitz-Kustner tests demonstrated no consistent differences in titers to microfilarial antigens between patent and amicrofilaremic ferrets. The results suggest a high level of immune responsiveness to antigens of mf in infected ferrets with no evidence of immunosuppression associated with prolonged microfilaremia or of major changes in immune responses with development of amicrofilaremic infections.  相似文献   
32.

Background:

Partial thickness rotator cuff tears occupy an important position in the spectrum of rotator cuff disease. The development of a more comprehensive classification has been sought to address both the tear location and extent, which may influence clinical results. The purpose of this study is to classify partial thickness rotator cuff tears according to the arthroscopic findings and to evaluate the clinical outcomes after arthroscopic repair of partial thickness tears.

Materials and Methods:

One hundred and two patients had arthroscopic treatment of partial thickness rotator cuff tears. The inclusion criterion for the study was a partially torn supraspinatus tendon involving articular or bursal side, verified by direct arthroscopic visualization. Outcome analysis was exclusively applied to patients who underwent transtendon repair, using the shoulder index of American Shoulder and Elbow Society and the University of California Los Angeles (UCLA) rating system.

Results:

Partial thickness rotator cuff tears were divided into five groups according to arthroscopic findings. There was significant improvement after surgery in all parameters of clinical evaluation in the tears that warranted repair. Arthroscopic repair in situ (transtendon technique) may be the preferred option in unstable partial thickness tear.

Conclusion:

The proposed classification system may assist decision making in the treatment of partial thickness rotator cuff tears.  相似文献   
33.

Background

Liver resection has long been considered the standard of care for resectable colorectal hepatic metastases (HM). Patients with colorectal peritoneal surface disease (PSD) are now also being treated with aggressive therapy in the form of cytoreductive surgery (CS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

Methods

A retrospective comparison of optimally-treated colorectal cancer patients with HM or PSD obtained from prospectively maintained databases (1991–2010).

Results

Liver resection was performed on 179 patients with HM, while 93 PSD patients received a complete cytoreduction followed by HIPEC. Patients differed in terms of age, performance status, site of primary cancer, T stage, and the use of perioperative chemotherapy. Five-year overall survival for HM patients was 36 %, with a median survival of 46 months, compared with 26 % and 34 months in patients with PSD (p = 0.024). When stratified by resection status, R0 HM (n = 170) and R0 PSD (n = 48) patients had similar median survival (49 vs. 41 months; p = 0.39). Median survival following R1 resection was also similar among HM (n = 9) and PSD (n = 45) patients (28 vs. 23 months; p = 0.68). Multivariate analysis identified distinctly different independent prognostic factors between HM and PSD patients. Major morbidity was 21 and 23 % (p = 0.88), while mortality was 3.9 versus 5.4 % (p = 0.55) in the HM and PSD patients, respectively.

Conclusion

Colorectal HM and PSD are distinct biologic diseases with different presentations and unique prognostic factors. However, long-term survival following CS/HIPEC is comparable to liver resection when stratified by completeness of resection. Furthermore, perioperative morbidity and mortality are similar.  相似文献   
34.
Intracellular recordings were obtained from the somata of type A and C primary afferents in the isolated bullfrog dorsal root ganglion (DRG) preparation. Bath application of serotonin (5-HT) in concentrations of 0.25-1.0 mM led to slow and fast depolarizing responses. Slow, maintained 5-HT depolarizations were observed in 47% of type A and 70% of type C neurons. These slow depolarizations were associated with an underlying increase in input resistance (Rin). In some type A neurons, the Rin increase was masked by a decrease in Rin due to depolarization-induced rectification. The slow 5-HT depolarization of type A, but not type C neurons showed pronounced tachyphylaxis to repeated 5-HT applications. In type C afferents, serotonin's slow action was often accompanied by spontaneous firing. Manganese decreased slow 5-HT depolarizations of both cell types. A slow depolarization and excitation of type C afferents by methysergide and cinanserin was also observed. Fast transient 5-HT depolarizations accompanied by a rapid decrease in Rin were observed in 7% of type A and 24% of type C neurons. In some DRG cells the fast and slow depolarizations combined to form a biphasic response. The actions of 5-HT reported here resemble in some ways 5-HT responses recorded extracellularly from the spinal terminations of primary afferents.  相似文献   
35.
Periodic Hematopoiesis in Human Cyclic Neutropenia   总被引:5,自引:1,他引:4       下载免费PDF全文
Human cyclic neutropenia is characterized by severe depression of blood neutrophil levels approximately every 21 days. To investigate the mechanism of cyclic neutropenia four patients were studied with daily complete blood counts, serial bone marrow examinations, marrow reserve testing, serum muramidase determinations, DF22P granulocytokinetic studies, and, in one patient, in vivo [3H]TdR labeling. Periodogram analysis of the serial blood counts in the latter patient and visual inspection of multiple cycles in the others revealed periodic fluctuations in the levels of blood neutrophils, monocytes, lymphocytes, reticulocytes, and platelets. Rhythmic changes in the morphologic and radioisotopic studies as well as the marrow reserve tests and muramidase measurements were consonant with a mechanism of periodic failure of marrow production rather than peripheral destruction. Human cyclic neutropenia is analogous to cyclic neutropenia in the grey collie dog and may be viewed as the consequence of cyclic hematopoiesis.  相似文献   
36.
Bone matrix demineralized in 0.6 N HCl at 2° for 24 h and implanted in muscle in allogeneic rats possesses consistently reproducible bone morphogenetic activity. Experiments on implants of matrix, obtained from donors injected with3H-tyrosine or3H-tryptophan, or Na35SO4, suggest that bone morphogenetic property is a protein or apart of a protein that is (1) insoluble in buffer solutions, pH 3.6 and 5.0; (2) degraded in buffer solutions at pH 7.4 by an endogenous sulfhydryl-group neutral proteinase; (3) digested by trypsin at 15° within 8 h without solubilization of the helical regions, possibly even without degradation of the nonhelical ends of the bone collagen molecule, and without any loss of the periodic ultrastructure of the collagen fibrils; (4) degraded or removed by 0.1 N NaOH at 2° within 24 h without solubilization of collagen; (5) biologically active even after nitration of tyrosyl groups with tetranitromethane. The release of only one-third of the radioactivity with loss of nearly all yield of new bone by limited tryptic digestion of3H-borohydride-reduced matrix indicates that the bone morphogenetic response is the function of a non-collagenous component. Autoradiographs of implants of matrix with non-collagenous proteins labelled with3H-tryptophan,3H-tyrosine, or both3H-tyrosine and3H-phenyl-alanine demonstrate random dissemination of the radioactive constituents and no evidence of local transfer of labelled proteins or soluble protein derivatives. Hypothetically, the bone morphogenetic response is controlled by an insoluble acidic bone morphogenetic protein or polypeptide (BMP) and a soluble neutral proteinase (BMP-ase) resembling trypsin in activity except functionally more specific for BMP. Firmly bound but separable from bone collagen, BMP is one of many short-lived morphogenetic substances appearing and disappearing throughout embryonic development and persisting in postfetal life. Where the BMP receptor resides and how it activates cell mechanisms of differential repression and derepression of such genes as code for osteogenesis is unknown.  相似文献   
37.
The peculiarities of the cystic pancreatic tumor morphogenesis were studied up. Possibility and probability of the anastomosis existence between mucinous cystic tumor and pancreatic duct with its secondary mucinous dilatation were confirmed, causing the complications occurrence, an acute pancreatitis in particular. Selecting the surgical tactic in mucinous cystic tumor it is necessary to take into account the probability of the intraductal malignization foci formation, what precludes application of extended pancreatic resection using adjuvant chemotherapy and the postoperative serological control conduction.  相似文献   
38.
In the USA, partner non-monogamy is reported to be more common among African American women than White women and may contribute to African American women’s increased risk for HIV and other sexually transmitted infections (STIs). Few studies have explicitly and comprehensively described the protective behaviours that African American women employ with non-monogamous partners to reduce their HIV risk. We conducted interviews to examine protective behaviours among 11 African American women aged 18–24 years who perceived that a partner in the preceding 12 months had another sex partner. Participants described three types of partnerships with 29 non-monogamous men; these partnerships clustered into three categories. Narrative analysis revealed an overall paucity of protective behaviours with non-monogamous partners. Protective behaviours (i.e. communication and condom use) were informed by partnership type, rather than perceptions of non-monogamy. There were few instances in which partner non-monogamy motivated women to terminate sex partnerships. Rather, these decisions were often motivated by changes in other relationship dynamics. To address HIV/STI risk related to partner non-monogamy, HIV prevention strategies for young African American women should emphasise the importance of condom use in all non-marital partnership types. Interventions where testing is available may be effective for women who frequently test for HIV/STIs but do not use condoms.  相似文献   
39.

Introduction

Minority women, particularly immigrants, have lower cancer screening rates than Caucasian women, but little else is known about cancer screening among immigrant women. Our objective was to assess breast, cervical, and colorectal cancer screening rates among immigrant women from Cambodia, Somalia, and Vietnam and explore screening barriers.

Methods

We measured screening rates by systematic chart review (N = 100) and qualitatively explored screening barriers via face-to-face questionnaire (N = 15) of women aged 50–75 from Cambodia, Somalia, and Vietnam attending a general medicine clinic (Portland, Maine, USA).

Results

Chart Review – Somali women were at higher risk of being unscreened for breast, cervical, and colorectal cancer compared with Cambodian and Vietnamese women. A longer period of US residency was associated with being screened for colorectal cancer. We observed a 7% (OR 1.07, 95% CI 1.01–1.13, p = 0.01) increase in the odds that a woman would undergo a fecal occult blood test for each additional year in the US, and a 39% increase in the odds of a woman being screened by colonoscopy or flexible sigmoidoscopy for every five years of additional US residence (OR 1.39, 95% CI 1.21–1.61, p = 0.02). We did not observe statistically significant relationships between odds of being screened by mammography, clinical breast exam or papanicolaou test according to years in the US. Questionnaire – We identified several barriers to breast, cervical, and colorectal cancer screening, including discomfort with exams conducted by male physicians.

Discussion

Somali women were less likely to be screened for breast, cervical, and colorectal cancer than Cambodian and Vietnamese women in this population, and uptake of colorectal cancer screening is associated with years of residency in this country. Future efforts to improve equity in cancer screening among immigrants may require both provider and community education.  相似文献   
40.
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